Revert https://codereview.chromium.org/1291903002 (protobuf roll).

third_party/protobuf/ruby/ext/google/protobuf_c/upb.c

-// Amalgamated source file
-#include "upb.h"
-
-
-#include <stdlib.h>
-#include <string.h>
-
-typedef struct {
-  size_t len;
-  char str[1];  /* Null-terminated string data follows. */
-} str_t;
-
-static str_t *newstr(const char *data, size_t len) {
-  str_t *ret = malloc(sizeof(*ret) + len);
-  if (!ret) return NULL;
-  ret->len = len;
-  memcpy(ret->str, data, len);
-  ret->str[len] = '\0';
-  return ret;
-}
-
-static void freestr(str_t *s) { free(s); }
-
-/* isalpha() etc. from <ctype.h> are locale-dependent, which we don't want. */
-static bool upb_isbetween(char c, char low, char high) {
-  return c >= low && c <= high;
-}
-
-static bool upb_isletter(char c) {
-  return upb_isbetween(c, 'A', 'Z') || upb_isbetween(c, 'a', 'z') || c == '_';
-}
-
-static bool upb_isalphanum(char c) {
-  return upb_isletter(c) || upb_isbetween(c, '0', '9');
-}
-
-static bool upb_isident(const char *str, size_t len, bool full, upb_status *s) {
-  bool start = true;
-  size_t i;
-  for (i = 0; i < len; i++) {
-    char c = str[i];
-    if (c == '.') {
-      if (start || !full) {
-        upb_status_seterrf(s, "invalid name: unexpected '.' (%s)", str);
-        return false;
-      }
-      start = true;
-    } else if (start) {
-      if (!upb_isletter(c)) {
-        upb_status_seterrf(
-            s, "invalid name: path components must start with a letter (%s)",
-            str);
-        return false;
-      }
-      start = false;
-    } else {
-      if (!upb_isalphanum(c)) {
-        upb_status_seterrf(s, "invalid name: non-alphanumeric character (%s)",
-                           str);
-        return false;
-      }
-    }
-  }
-  return !start;
-}
-
-
-/* upb_def ********************************************************************/
-
-upb_deftype_t upb_def_type(const upb_def *d) { return d->type; }
-
-const char *upb_def_fullname(const upb_def *d) { return d->fullname; }
-
-bool upb_def_setfullname(upb_def *def, const char *fullname, upb_status *s) {
-  assert(!upb_def_isfrozen(def));
-  if (!upb_isident(fullname, strlen(fullname), true, s)) return false;
-  free((void*)def->fullname);
-  def->fullname = upb_strdup(fullname);
-  return true;
-}
-
-upb_def *upb_def_dup(const upb_def *def, const void *o) {
-  switch (def->type) {
-    case UPB_DEF_MSG:
-      return upb_msgdef_upcast_mutable(
-          upb_msgdef_dup(upb_downcast_msgdef(def), o));
-    case UPB_DEF_FIELD:
-      return upb_fielddef_upcast_mutable(
-          upb_fielddef_dup(upb_downcast_fielddef(def), o));
-    case UPB_DEF_ENUM:
-      return upb_enumdef_upcast_mutable(
-          upb_enumdef_dup(upb_downcast_enumdef(def), o));
-    default: assert(false); return NULL;
-  }
-}
-
-static bool upb_def_init(upb_def *def, upb_deftype_t type,
-                         const struct upb_refcounted_vtbl *vtbl,
-                         const void *owner) {
-  if (!upb_refcounted_init(upb_def_upcast_mutable(def), vtbl, owner)) return false;
-  def->type = type;
-  def->fullname = NULL;
-  def->came_from_user = false;
-  return true;
-}
-
-static void upb_def_uninit(upb_def *def) {
-  free((void*)def->fullname);
-}
-
-static const char *msgdef_name(const upb_msgdef *m) {
-  const char *name = upb_def_fullname(upb_msgdef_upcast(m));
-  return name ? name : "(anonymous)";
-}
-
-static bool upb_validate_field(upb_fielddef *f, upb_status *s) {
-  if (upb_fielddef_name(f) == NULL || upb_fielddef_number(f) == 0) {
-    upb_status_seterrmsg(s, "fielddef must have name and number set");
-    return false;
-  }
-
-  if (!f->type_is_set_) {
-    upb_status_seterrmsg(s, "fielddef type was not initialized");
-    return false;
-  }
-
-  if (upb_fielddef_lazy(f) &&
-      upb_fielddef_descriptortype(f) != UPB_DESCRIPTOR_TYPE_MESSAGE) {
-    upb_status_seterrmsg(s,
-                         "only length-delimited submessage fields may be lazy");
-    return false;
-  }
-
-  if (upb_fielddef_hassubdef(f)) {
-    const upb_def *subdef;
-
-    if (f->subdef_is_symbolic) {
-      upb_status_seterrf(s, "field '%s.%s' has not been resolved",
-                         msgdef_name(f->msg.def), upb_fielddef_name(f));
-      return false;
-    }
-
-    subdef = upb_fielddef_subdef(f);
-    if (subdef == NULL) {
-      upb_status_seterrf(s, "field %s.%s is missing required subdef",
-                         msgdef_name(f->msg.def), upb_fielddef_name(f));
-      return false;
-    }
-
-    if (!upb_def_isfrozen(subdef) && !subdef->came_from_user) {
-      upb_status_seterrf(s,
-                         "subdef of field %s.%s is not frozen or being frozen",
-                         msgdef_name(f->msg.def), upb_fielddef_name(f));
-      return false;
-    }
-  }
-
-  if (upb_fielddef_type(f) == UPB_TYPE_ENUM) {
-    bool has_default_name = upb_fielddef_enumhasdefaultstr(f);
-    bool has_default_number = upb_fielddef_enumhasdefaultint32(f);
-
-    /* Previously verified by upb_validate_enumdef(). */
-    assert(upb_enumdef_numvals(upb_fielddef_enumsubdef(f)) > 0);
-
-    /* We've already validated that we have an associated enumdef and that it
-     * has at least one member, so at least one of these should be true.
-     * Because if the user didn't set anything, we'll pick up the enum's
-     * default, but if the user *did* set something we should at least pick up
-     * the one they set (int32 or string). */
-    assert(has_default_name || has_default_number);
-
-    if (!has_default_name) {
-      upb_status_seterrf(s,
-                         "enum default for field %s.%s (%d) is not in the enum",
-                         msgdef_name(f->msg.def), upb_fielddef_name(f),
-                         upb_fielddef_defaultint32(f));
-      return false;
-    }
-
-    if (!has_default_number) {
-      upb_status_seterrf(s,
-                         "enum default for field %s.%s (%s) is not in the enum",
-                         msgdef_name(f->msg.def), upb_fielddef_name(f),
-                         upb_fielddef_defaultstr(f, NULL));
-      return false;
-    }
-
-    /* Lift the effective numeric default into the field's default slot, in case
-     * we were only getting it "by reference" from the enumdef. */
-    upb_fielddef_setdefaultint32(f, upb_fielddef_defaultint32(f));
-  }
-
-  /* Ensure that MapEntry submessages only appear as repeated fields, not
-   * optional/required (singular) fields. */
-  if (upb_fielddef_type(f) == UPB_TYPE_MESSAGE &&
-      upb_fielddef_msgsubdef(f) != NULL) {
-    const upb_msgdef *subdef = upb_fielddef_msgsubdef(f);
-    if (upb_msgdef_mapentry(subdef) && !upb_fielddef_isseq(f)) {
-      upb_status_seterrf(s,
-                         "Field %s refers to mapentry message but is not "
-                         "a repeated field",
-                         upb_fielddef_name(f) ? upb_fielddef_name(f) :
-                         "(unnamed)");
-      return false;
-    }
-  }
-
-  return true;
-}
-
-static bool upb_validate_enumdef(const upb_enumdef *e, upb_status *s) {
-  if (upb_enumdef_numvals(e) == 0) {
-    upb_status_seterrf(s, "enum %s has no members (must have at least one)",
-                       upb_enumdef_fullname(e));
-    return false;
-  }
-
-  return true;
-}
-
-/* All submessage fields are lower than all other fields.
- * Secondly, fields are increasing in order. */
-uint32_t field_rank(const upb_fielddef *f) {
-  uint32_t ret = upb_fielddef_number(f);
-  const uint32_t high_bit = 1 << 30;
-  assert(ret < high_bit);
-  if (!upb_fielddef_issubmsg(f))
-    ret |= high_bit;
-  return ret;
-}
-
-int cmp_fields(const void *p1, const void *p2) {
-  const upb_fielddef *f1 = *(upb_fielddef*const*)p1;
-  const upb_fielddef *f2 = *(upb_fielddef*const*)p2;
-  return field_rank(f1) - field_rank(f2);
-}
-
-static bool assign_msg_indices(upb_msgdef *m, upb_status *s) {
-  /* Sort fields.  upb internally relies on UPB_TYPE_MESSAGE fields having the
-   * lowest indexes, but we do not publicly guarantee this. */
-  upb_msg_field_iter j;
-  int i;
-  uint32_t selector;
-  int n = upb_msgdef_numfields(m);
-  upb_fielddef **fields = malloc(n * sizeof(*fields));
-  if (!fields) return false;
-
-  m->submsg_field_count = 0;
-  for(i = 0, upb_msg_field_begin(&j, m);
-      !upb_msg_field_done(&j);
-      upb_msg_field_next(&j), i++) {
-    upb_fielddef *f = upb_msg_iter_field(&j);
-    assert(f->msg.def == m);
-    if (!upb_validate_field(f, s)) {
-      free(fields);
-      return false;
-    }
-    if (upb_fielddef_issubmsg(f)) {
-      m->submsg_field_count++;
-    }
-    fields[i] = f;
-  }
-
-  qsort(fields, n, sizeof(*fields), cmp_fields);
-
-  selector = UPB_STATIC_SELECTOR_COUNT + m->submsg_field_count;
-  for (i = 0; i < n; i++) {
-    upb_fielddef *f = fields[i];
-    f->index_ = i;
-    f->selector_base = selector + upb_handlers_selectorbaseoffset(f);
-    selector += upb_handlers_selectorcount(f);
-  }
-  m->selector_count = selector;
-
-#ifndef NDEBUG
-  {
-    /* Verify that all selectors for the message are distinct. */
-#define TRY(type) \
-    if (upb_handlers_getselector(f, type, &sel)) upb_inttable_insert(&t, sel, v);
-
-    upb_inttable t;
-    upb_value v;
-    upb_selector_t sel;
-
-    upb_inttable_init(&t, UPB_CTYPE_BOOL);
-    v = upb_value_bool(true);
-    upb_inttable_insert(&t, UPB_STARTMSG_SELECTOR, v);
-    upb_inttable_insert(&t, UPB_ENDMSG_SELECTOR, v);
-    for(upb_msg_field_begin(&j, m);
-        !upb_msg_field_done(&j);
-        upb_msg_field_next(&j)) {
-      upb_fielddef *f = upb_msg_iter_field(&j);
-      /* These calls will assert-fail in upb_table if the value already
-       * exists. */
-      TRY(UPB_HANDLER_INT32);
-      TRY(UPB_HANDLER_INT64)
-      TRY(UPB_HANDLER_UINT32)
-      TRY(UPB_HANDLER_UINT64)
-      TRY(UPB_HANDLER_FLOAT)
-      TRY(UPB_HANDLER_DOUBLE)
-      TRY(UPB_HANDLER_BOOL)
-      TRY(UPB_HANDLER_STARTSTR)
-      TRY(UPB_HANDLER_STRING)
-      TRY(UPB_HANDLER_ENDSTR)
-      TRY(UPB_HANDLER_STARTSUBMSG)
-      TRY(UPB_HANDLER_ENDSUBMSG)
-      TRY(UPB_HANDLER_STARTSEQ)
-      TRY(UPB_HANDLER_ENDSEQ)
-    }
-    upb_inttable_uninit(&t);
-  }
-#undef TRY
-#endif
-
-  free(fields);
-  return true;
-}
-
-bool upb_def_freeze(upb_def *const* defs, int n, upb_status *s) {
-  int i;
-  int maxdepth;
-  bool ret;
-  upb_status_clear(s);
-
-  /* First perform validation, in two passes so we can check that we have a
-   * transitive closure without needing to search. */
-  for (i = 0; i < n; i++) {
-    upb_def *def = defs[i];
-    if (upb_def_isfrozen(def)) {
-      /* Could relax this requirement if it's annoying. */
-      upb_status_seterrmsg(s, "def is already frozen");
-      goto err;
-    } else if (def->type == UPB_DEF_FIELD) {
-      upb_status_seterrmsg(s, "standalone fielddefs can not be frozen");
-      goto err;
-    } else if (def->type == UPB_DEF_ENUM) {
-      if (!upb_validate_enumdef(upb_dyncast_enumdef(def), s)) {
-        goto err;
-      }
-    } else {
-      /* Set now to detect transitive closure in the second pass. */
-      def->came_from_user = true;
-    }
-  }
-
-  /* Second pass of validation.  Also assign selector bases and indexes, and
-   * compact tables. */
-  for (i = 0; i < n; i++) {
-    upb_msgdef *m = upb_dyncast_msgdef_mutable(defs[i]);
-    upb_enumdef *e = upb_dyncast_enumdef_mutable(defs[i]);
-    if (m) {
-      upb_inttable_compact(&m->itof);
-      if (!assign_msg_indices(m, s)) {
-        goto err;
-      }
-    } else if (e) {
-      upb_inttable_compact(&e->iton);
-    }
-  }
-
-  /* Def graph contains FieldDefs between each MessageDef, so double the
-   * limit. */
-  maxdepth = UPB_MAX_MESSAGE_DEPTH * 2;
-
-  /* Validation all passed; freeze the defs. */
-  ret = upb_refcounted_freeze((upb_refcounted * const *)defs, n, s, maxdepth);
-  assert(!(s && ret != upb_ok(s)));
-  return ret;
-
-err:
-  for (i = 0; i < n; i++) {
-    defs[i]->came_from_user = false;
-  }
-  assert(!(s && upb_ok(s)));
-  return false;
-}
-
-
-/* upb_enumdef ****************************************************************/
-
-static void upb_enumdef_free(upb_refcounted *r) {
-  upb_enumdef *e = (upb_enumdef*)r;
-  upb_inttable_iter i;
-  upb_inttable_begin(&i, &e->iton);
-  for( ; !upb_inttable_done(&i); upb_inttable_next(&i)) {
-    /* To clean up the upb_strdup() from upb_enumdef_addval(). */
-    free(upb_value_getcstr(upb_inttable_iter_value(&i)));
-  }
-  upb_strtable_uninit(&e->ntoi);
-  upb_inttable_uninit(&e->iton);
-  upb_def_uninit(upb_enumdef_upcast_mutable(e));
-  free(e);
-}
-
-upb_enumdef *upb_enumdef_new(const void *owner) {
-  static const struct upb_refcounted_vtbl vtbl = {NULL, &upb_enumdef_free};
-  upb_enumdef *e = malloc(sizeof(*e));
-  if (!e) return NULL;
-  if (!upb_def_init(upb_enumdef_upcast_mutable(e), UPB_DEF_ENUM, &vtbl, owner))
-    goto err2;
-  if (!upb_strtable_init(&e->ntoi, UPB_CTYPE_INT32)) goto err2;
-  if (!upb_inttable_init(&e->iton, UPB_CTYPE_CSTR)) goto err1;
-  return e;
-
-err1:
-  upb_strtable_uninit(&e->ntoi);
-err2:
-  free(e);
-  return NULL;
-}
-
-upb_enumdef *upb_enumdef_dup(const upb_enumdef *e, const void *owner) {
-  upb_enum_iter i;
-  upb_enumdef *new_e = upb_enumdef_new(owner);
-  if (!new_e) return NULL;
-  for(upb_enum_begin(&i, e); !upb_enum_done(&i); upb_enum_next(&i)) {
-    bool success = upb_enumdef_addval(
-        new_e, upb_enum_iter_name(&i),upb_enum_iter_number(&i), NULL);
-    if (!success) {
-      upb_enumdef_unref(new_e, owner);
-      return NULL;
-    }
-  }
-  return new_e;
-}
-
-bool upb_enumdef_freeze(upb_enumdef *e, upb_status *status) {
-  upb_def *d = upb_enumdef_upcast_mutable(e);
-  return upb_def_freeze(&d, 1, status);
-}
-
-const char *upb_enumdef_fullname(const upb_enumdef *e) {
-  return upb_def_fullname(upb_enumdef_upcast(e));
-}
-
-bool upb_enumdef_setfullname(upb_enumdef *e, const char *fullname,
-                             upb_status *s) {
-  return upb_def_setfullname(upb_enumdef_upcast_mutable(e), fullname, s);
-}
-
-bool upb_enumdef_addval(upb_enumdef *e, const char *name, int32_t num,
-                        upb_status *status) {
-  if (!upb_isident(name, strlen(name), false, status)) {
-    return false;
-  }
-  if (upb_enumdef_ntoiz(e, name, NULL)) {
-    upb_status_seterrf(status, "name '%s' is already defined", name);
-    return false;
-  }
-  if (!upb_strtable_insert(&e->ntoi, name, upb_value_int32(num))) {
-    upb_status_seterrmsg(status, "out of memory");
-    return false;
-  }
-  if (!upb_inttable_lookup(&e->iton, num, NULL) &&
-      !upb_inttable_insert(&e->iton, num, upb_value_cstr(upb_strdup(name)))) {
-    upb_status_seterrmsg(status, "out of memory");
-    upb_strtable_remove(&e->ntoi, name, NULL);
-    return false;
-  }
-  if (upb_enumdef_numvals(e) == 1) {
-    bool ok = upb_enumdef_setdefault(e, num, NULL);
-    UPB_ASSERT_VAR(ok, ok);
-  }
-  return true;
-}
-
-int32_t upb_enumdef_default(const upb_enumdef *e) {
-  assert(upb_enumdef_iton(e, e->defaultval));
-  return e->defaultval;
-}
-
-bool upb_enumdef_setdefault(upb_enumdef *e, int32_t val, upb_status *s) {
-  assert(!upb_enumdef_isfrozen(e));
-  if (!upb_enumdef_iton(e, val)) {
-    upb_status_seterrf(s, "number '%d' is not in the enum.", val);
-    return false;
-  }
-  e->defaultval = val;
-  return true;
-}
-
-int upb_enumdef_numvals(const upb_enumdef *e) {
-  return upb_strtable_count(&e->ntoi);
-}
-
-void upb_enum_begin(upb_enum_iter *i, const upb_enumdef *e) {
-  /* We iterate over the ntoi table, to account for duplicate numbers. */
-  upb_strtable_begin(i, &e->ntoi);
-}
-
-void upb_enum_next(upb_enum_iter *iter) { upb_strtable_next(iter); }
-bool upb_enum_done(upb_enum_iter *iter) { return upb_strtable_done(iter); }
-
-bool upb_enumdef_ntoi(const upb_enumdef *def, const char *name,
-                      size_t len, int32_t *num) {
-  upb_value v;
-  if (!upb_strtable_lookup2(&def->ntoi, name, len, &v)) {
-    return false;
-  }
-  if (num) *num = upb_value_getint32(v);
-  return true;
-}
-
-const char *upb_enumdef_iton(const upb_enumdef *def, int32_t num) {
-  upb_value v;
-  return upb_inttable_lookup32(&def->iton, num, &v) ?
-      upb_value_getcstr(v) : NULL;
-}
-
-const char *upb_enum_iter_name(upb_enum_iter *iter) {
-  return upb_strtable_iter_key(iter);
-}
-
-int32_t upb_enum_iter_number(upb_enum_iter *iter) {
-  return upb_value_getint32(upb_strtable_iter_value(iter));
-}
-
-
-/* upb_fielddef ***************************************************************/
-
-static void upb_fielddef_init_default(upb_fielddef *f);
-
-static void upb_fielddef_uninit_default(upb_fielddef *f) {
-  if (f->type_is_set_ && f->default_is_string && f->defaultval.bytes)
-    freestr(f->defaultval.bytes);
-}
-
-static void visitfield(const upb_refcounted *r, upb_refcounted_visit *visit,
-                       void *closure) {
-  const upb_fielddef *f = (const upb_fielddef*)r;
-  if (upb_fielddef_containingtype(f)) {
-    visit(r, upb_msgdef_upcast2(upb_fielddef_containingtype(f)), closure);
-  }
-  if (upb_fielddef_containingoneof(f)) {
-    visit(r, upb_oneofdef_upcast2(upb_fielddef_containingoneof(f)), closure);
-  }
-  if (upb_fielddef_subdef(f)) {
-    visit(r, upb_def_upcast(upb_fielddef_subdef(f)), closure);
-  }
-}
-
-static void freefield(upb_refcounted *r) {
-  upb_fielddef *f = (upb_fielddef*)r;
-  upb_fielddef_uninit_default(f);
-  if (f->subdef_is_symbolic)
-    free(f->sub.name);
-  upb_def_uninit(upb_fielddef_upcast_mutable(f));
-  free(f);
-}
-
-static const char *enumdefaultstr(const upb_fielddef *f) {
-  const upb_enumdef *e;
-  assert(f->type_is_set_ && f->type_ == UPB_TYPE_ENUM);
-  e = upb_fielddef_enumsubdef(f);
-  if (f->default_is_string && f->defaultval.bytes) {
-    /* Default was explicitly set as a string. */
-    str_t *s = f->defaultval.bytes;
-    return s->str;
-  } else if (e) {
-    if (!f->default_is_string) {
-      /* Default was explicitly set as an integer; look it up in enumdef. */
-      const char *name = upb_enumdef_iton(e, f->defaultval.sint);
-      if (name) {
-        return name;
-      }
-    } else {
-      /* Default is completely unset; pull enumdef default. */
-      if (upb_enumdef_numvals(e) > 0) {
-        const char *name = upb_enumdef_iton(e, upb_enumdef_default(e));
-        assert(name);
-        return name;
-      }
-    }
-  }
-  return NULL;
-}
-
-static bool enumdefaultint32(const upb_fielddef *f, int32_t *val) {
-  const upb_enumdef *e;
-  assert(f->type_is_set_ && f->type_ == UPB_TYPE_ENUM);
-  e = upb_fielddef_enumsubdef(f);
-  if (!f->default_is_string) {
-    /* Default was explicitly set as an integer. */
-    *val = f->defaultval.sint;
-    return true;
-  } else if (e) {
-    if (f->defaultval.bytes) {
-      /* Default was explicitly set as a str; try to lookup corresponding int. */
-      str_t *s = f->defaultval.bytes;
-      if (upb_enumdef_ntoiz(e, s->str, val)) {
-        return true;
-      }
-    } else {
-      /* Default is unset; try to pull in enumdef default. */
-      if (upb_enumdef_numvals(e) > 0) {
-        *val = upb_enumdef_default(e);
-        return true;
-      }
-    }
-  }
-  return false;
-}
-
-upb_fielddef *upb_fielddef_new(const void *o) {
-  static const struct upb_refcounted_vtbl vtbl = {visitfield, freefield};
-  upb_fielddef *f = malloc(sizeof(*f));
-  if (!f) return NULL;
-  if (!upb_def_init(upb_fielddef_upcast_mutable(f), UPB_DEF_FIELD, &vtbl, o)) {
-    free(f);
-    return NULL;
-  }
-  f->msg.def = NULL;
-  f->sub.def = NULL;
-  f->oneof = NULL;
-  f->subdef_is_symbolic = false;
-  f->msg_is_symbolic = false;
-  f->label_ = UPB_LABEL_OPTIONAL;
-  f->type_ = UPB_TYPE_INT32;
-  f->number_ = 0;
-  f->type_is_set_ = false;
-  f->tagdelim = false;
-  f->is_extension_ = false;
-  f->lazy_ = false;
-  f->packed_ = true;
-
-  /* For the moment we default this to UPB_INTFMT_VARIABLE, since it will work
-   * with all integer types and is in some since more "default" since the most
-   * normal-looking proto2 types int32/int64/uint32/uint64 use variable.
-   *
-   * Other options to consider:
-   * - there is no default; users must set this manually (like type).
-   * - default signed integers to UPB_INTFMT_ZIGZAG, since it's more likely to
-   *   be an optimal default for signed integers. */
-  f->intfmt = UPB_INTFMT_VARIABLE;
-  return f;
-}
-
-upb_fielddef *upb_fielddef_dup(const upb_fielddef *f, const void *owner) {
-  const char *srcname;
-  upb_fielddef *newf = upb_fielddef_new(owner);
-  if (!newf) return NULL;
-  upb_fielddef_settype(newf, upb_fielddef_type(f));
-  upb_fielddef_setlabel(newf, upb_fielddef_label(f));
-  upb_fielddef_setnumber(newf, upb_fielddef_number(f), NULL);
-  upb_fielddef_setname(newf, upb_fielddef_name(f), NULL);
-  if (f->default_is_string && f->defaultval.bytes) {
-    str_t *s = f->defaultval.bytes;
-    upb_fielddef_setdefaultstr(newf, s->str, s->len, NULL);
-  } else {
-    newf->default_is_string = f->default_is_string;
-    newf->defaultval = f->defaultval;
-  }
-
-  if (f->subdef_is_symbolic) {
-    srcname = f->sub.name;  /* Might be NULL. */
-  } else {
-    srcname = f->sub.def ? upb_def_fullname(f->sub.def) : NULL;
-  }
-  if (srcname) {
-    char *newname = malloc(strlen(f->sub.def->fullname) + 2);
-    if (!newname) {
-      upb_fielddef_unref(newf, owner);
-      return NULL;
-    }
-    strcpy(newname, ".");
-    strcat(newname, f->sub.def->fullname);
-    upb_fielddef_setsubdefname(newf, newname, NULL);
-    free(newname);
-  }
-
-  return newf;
-}
-
-bool upb_fielddef_typeisset(const upb_fielddef *f) {
-  return f->type_is_set_;
-}
-
-upb_fieldtype_t upb_fielddef_type(const upb_fielddef *f) {
-  assert(f->type_is_set_);
-  return f->type_;
-}
-
-uint32_t upb_fielddef_index(const upb_fielddef *f) {
-  return f->index_;
-}
-
-upb_label_t upb_fielddef_label(const upb_fielddef *f) {
-  return f->label_;
-}
-
-upb_intfmt_t upb_fielddef_intfmt(const upb_fielddef *f) {
-  return f->intfmt;
-}
-
-bool upb_fielddef_istagdelim(const upb_fielddef *f) {
-  return f->tagdelim;
-}
-
-uint32_t upb_fielddef_number(const upb_fielddef *f) {
-  return f->number_;
-}
-
-bool upb_fielddef_isextension(const upb_fielddef *f) {
-  return f->is_extension_;
-}
-
-bool upb_fielddef_lazy(const upb_fielddef *f) {
-  return f->lazy_;
-}
-
-bool upb_fielddef_packed(const upb_fielddef *f) {
-  return f->packed_;
-}
-
-const char *upb_fielddef_name(const upb_fielddef *f) {
-  return upb_def_fullname(upb_fielddef_upcast(f));
-}
-
-const upb_msgdef *upb_fielddef_containingtype(const upb_fielddef *f) {
-  return f->msg_is_symbolic ? NULL : f->msg.def;
-}
-
-const upb_oneofdef *upb_fielddef_containingoneof(const upb_fielddef *f) {
-  return f->oneof;
-}
-
-upb_msgdef *upb_fielddef_containingtype_mutable(upb_fielddef *f) {
-  return (upb_msgdef*)upb_fielddef_containingtype(f);
-}
-
-const char *upb_fielddef_containingtypename(upb_fielddef *f) {
-  return f->msg_is_symbolic ? f->msg.name : NULL;
-}
-
-static void release_containingtype(upb_fielddef *f) {
-  if (f->msg_is_symbolic) free(f->msg.name);
-}
-
-bool upb_fielddef_setcontainingtypename(upb_fielddef *f, const char *name,
-                                        upb_status *s) {
-  assert(!upb_fielddef_isfrozen(f));
-  if (upb_fielddef_containingtype(f)) {
-    upb_status_seterrmsg(s, "field has already been added to a message.");
-    return false;
-  }
-  /* TODO: validate name (upb_isident() doesn't quite work atm because this name
-   * may have a leading "."). */
-  release_containingtype(f);
-  f->msg.name = upb_strdup(name);
-  f->msg_is_symbolic = true;
-  return true;
-}
-
-bool upb_fielddef_setname(upb_fielddef *f, const char *name, upb_status *s) {
-  if (upb_fielddef_containingtype(f) || upb_fielddef_containingoneof(f)) {
-    upb_status_seterrmsg(s, "Already added to message or oneof");
-    return false;
-  }
-  return upb_def_setfullname(upb_fielddef_upcast_mutable(f), name, s);
-}
-
-static void chkdefaulttype(const upb_fielddef *f, upb_fieldtype_t type) {
-  UPB_UNUSED(f);
-  UPB_UNUSED(type);
-  assert(f->type_is_set_ && upb_fielddef_type(f) == type);
-}
-
-int64_t upb_fielddef_defaultint64(const upb_fielddef *f) {
-  chkdefaulttype(f, UPB_TYPE_INT64);
-  return f->defaultval.sint;
-}
-
-int32_t upb_fielddef_defaultint32(const upb_fielddef *f) {
-  if (f->type_is_set_ && upb_fielddef_type(f) == UPB_TYPE_ENUM) {
-    int32_t val;
-    bool ok = enumdefaultint32(f, &val);
-    UPB_ASSERT_VAR(ok, ok);
-    return val;
-  } else {
-    chkdefaulttype(f, UPB_TYPE_INT32);
-    return f->defaultval.sint;
-  }
-}
-
-uint64_t upb_fielddef_defaultuint64(const upb_fielddef *f) {
-  chkdefaulttype(f, UPB_TYPE_UINT64);
-  return f->defaultval.uint;
-}
-
-uint32_t upb_fielddef_defaultuint32(const upb_fielddef *f) {
-  chkdefaulttype(f, UPB_TYPE_UINT32);
-  return f->defaultval.uint;
-}
-
-bool upb_fielddef_defaultbool(const upb_fielddef *f) {
-  chkdefaulttype(f, UPB_TYPE_BOOL);
-  return f->defaultval.uint;
-}
-
-float upb_fielddef_defaultfloat(const upb_fielddef *f) {
-  chkdefaulttype(f, UPB_TYPE_FLOAT);
-  return f->defaultval.flt;
-}
-
-double upb_fielddef_defaultdouble(const upb_fielddef *f) {
-  chkdefaulttype(f, UPB_TYPE_DOUBLE);
-  return f->defaultval.dbl;
-}
-
-const char *upb_fielddef_defaultstr(const upb_fielddef *f, size_t *len) {
-  assert(f->type_is_set_);
-  assert(upb_fielddef_type(f) == UPB_TYPE_STRING ||
-         upb_fielddef_type(f) == UPB_TYPE_BYTES ||
-         upb_fielddef_type(f) == UPB_TYPE_ENUM);
-
-  if (upb_fielddef_type(f) == UPB_TYPE_ENUM) {
-    const char *ret = enumdefaultstr(f);
-    assert(ret);
-    /* Enum defaults can't have embedded NULLs. */
-    if (len) *len = strlen(ret);
-    return ret;
-  }
-
-  if (f->default_is_string) {
-    str_t *str = f->defaultval.bytes;
-    if (len) *len = str->len;
-    return str->str;
-  }
-
-  return NULL;
-}
-
-static void upb_fielddef_init_default(upb_fielddef *f) {
-  f->default_is_string = false;
-  switch (upb_fielddef_type(f)) {
-    case UPB_TYPE_DOUBLE: f->defaultval.dbl = 0; break;
-    case UPB_TYPE_FLOAT: f->defaultval.flt = 0; break;
-    case UPB_TYPE_INT32:
-    case UPB_TYPE_INT64: f->defaultval.sint = 0; break;
-    case UPB_TYPE_UINT64:
-    case UPB_TYPE_UINT32:
-    case UPB_TYPE_BOOL: f->defaultval.uint = 0; break;
-    case UPB_TYPE_STRING:
-    case UPB_TYPE_BYTES:
-      f->defaultval.bytes = newstr("", 0);
-      f->default_is_string = true;
-      break;
-    case UPB_TYPE_MESSAGE: break;
-    case UPB_TYPE_ENUM:
-      /* This is our special sentinel that indicates "not set" for an enum. */
-      f->default_is_string = true;
-      f->defaultval.bytes = NULL;
-      break;
-  }
-}
-
-const upb_def *upb_fielddef_subdef(const upb_fielddef *f) {
-  return f->subdef_is_symbolic ? NULL : f->sub.def;
-}
-
-const upb_msgdef *upb_fielddef_msgsubdef(const upb_fielddef *f) {
-  const upb_def *def = upb_fielddef_subdef(f);
-  return def ? upb_dyncast_msgdef(def) : NULL;
-}
-
-const upb_enumdef *upb_fielddef_enumsubdef(const upb_fielddef *f) {
-  const upb_def *def = upb_fielddef_subdef(f);
-  return def ? upb_dyncast_enumdef(def) : NULL;
-}
-
-upb_def *upb_fielddef_subdef_mutable(upb_fielddef *f) {
-  return (upb_def*)upb_fielddef_subdef(f);
-}
-
-const char *upb_fielddef_subdefname(const upb_fielddef *f) {
-  if (f->subdef_is_symbolic) {
-    return f->sub.name;
-  } else if (f->sub.def) {
-    return upb_def_fullname(f->sub.def);
-  } else {
-    return NULL;
-  }
-}
-
-bool upb_fielddef_setnumber(upb_fielddef *f, uint32_t number, upb_status *s) {
-  if (upb_fielddef_containingtype(f)) {
-    upb_status_seterrmsg(
-        s, "cannot change field number after adding to a message");
-    return false;
-  }
-  if (number == 0 || number > UPB_MAX_FIELDNUMBER) {
-    upb_status_seterrf(s, "invalid field number (%u)", number);
-    return false;
-  }
-  f->number_ = number;
-  return true;
-}
-
-void upb_fielddef_settype(upb_fielddef *f, upb_fieldtype_t type) {
-  assert(!upb_fielddef_isfrozen(f));
-  assert(upb_fielddef_checktype(type));
-  upb_fielddef_uninit_default(f);
-  f->type_ = type;
-  f->type_is_set_ = true;
-  upb_fielddef_init_default(f);
-}
-
-void upb_fielddef_setdescriptortype(upb_fielddef *f, int type) {
-  assert(!upb_fielddef_isfrozen(f));
-  switch (type) {
-    case UPB_DESCRIPTOR_TYPE_DOUBLE:
-      upb_fielddef_settype(f, UPB_TYPE_DOUBLE);
-      break;
-    case UPB_DESCRIPTOR_TYPE_FLOAT:
-      upb_fielddef_settype(f, UPB_TYPE_FLOAT);
-      break;
-    case UPB_DESCRIPTOR_TYPE_INT64:
-    case UPB_DESCRIPTOR_TYPE_SFIXED64:
-    case UPB_DESCRIPTOR_TYPE_SINT64:
-      upb_fielddef_settype(f, UPB_TYPE_INT64);
-      break;
-    case UPB_DESCRIPTOR_TYPE_UINT64:
-    case UPB_DESCRIPTOR_TYPE_FIXED64:
-      upb_fielddef_settype(f, UPB_TYPE_UINT64);
-      break;
-    case UPB_DESCRIPTOR_TYPE_INT32:
-    case UPB_DESCRIPTOR_TYPE_SFIXED32:
-    case UPB_DESCRIPTOR_TYPE_SINT32:
-      upb_fielddef_settype(f, UPB_TYPE_INT32);
-      break;
-    case UPB_DESCRIPTOR_TYPE_UINT32:
-    case UPB_DESCRIPTOR_TYPE_FIXED32:
-      upb_fielddef_settype(f, UPB_TYPE_UINT32);
-      break;
-    case UPB_DESCRIPTOR_TYPE_BOOL:
-      upb_fielddef_settype(f, UPB_TYPE_BOOL);
-      break;
-    case UPB_DESCRIPTOR_TYPE_STRING:
-      upb_fielddef_settype(f, UPB_TYPE_STRING);
-      break;
-    case UPB_DESCRIPTOR_TYPE_BYTES:
-      upb_fielddef_settype(f, UPB_TYPE_BYTES);
-      break;
-    case UPB_DESCRIPTOR_TYPE_GROUP:
-    case UPB_DESCRIPTOR_TYPE_MESSAGE:
-      upb_fielddef_settype(f, UPB_TYPE_MESSAGE);
-      break;
-    case UPB_DESCRIPTOR_TYPE_ENUM:
-      upb_fielddef_settype(f, UPB_TYPE_ENUM);
-      break;
-    default: assert(false);
-  }
-
-  if (type == UPB_DESCRIPTOR_TYPE_FIXED64 ||
-      type == UPB_DESCRIPTOR_TYPE_FIXED32 ||
-      type == UPB_DESCRIPTOR_TYPE_SFIXED64 ||
-      type == UPB_DESCRIPTOR_TYPE_SFIXED32) {
-    upb_fielddef_setintfmt(f, UPB_INTFMT_FIXED);
-  } else if (type == UPB_DESCRIPTOR_TYPE_SINT64 ||
-             type == UPB_DESCRIPTOR_TYPE_SINT32) {
-    upb_fielddef_setintfmt(f, UPB_INTFMT_ZIGZAG);
-  } else {
-    upb_fielddef_setintfmt(f, UPB_INTFMT_VARIABLE);
-  }
-
-  upb_fielddef_settagdelim(f, type == UPB_DESCRIPTOR_TYPE_GROUP);
-}
-
-upb_descriptortype_t upb_fielddef_descriptortype(const upb_fielddef *f) {
-  switch (upb_fielddef_type(f)) {
-    case UPB_TYPE_FLOAT:  return UPB_DESCRIPTOR_TYPE_FLOAT;
-    case UPB_TYPE_DOUBLE: return UPB_DESCRIPTOR_TYPE_DOUBLE;
-    case UPB_TYPE_BOOL:   return UPB_DESCRIPTOR_TYPE_BOOL;
-    case UPB_TYPE_STRING: return UPB_DESCRIPTOR_TYPE_STRING;
-    case UPB_TYPE_BYTES:  return UPB_DESCRIPTOR_TYPE_BYTES;
-    case UPB_TYPE_ENUM:   return UPB_DESCRIPTOR_TYPE_ENUM;
-    case UPB_TYPE_INT32:
-      switch (upb_fielddef_intfmt(f)) {
-        case UPB_INTFMT_VARIABLE: return UPB_DESCRIPTOR_TYPE_INT32;
-        case UPB_INTFMT_FIXED:    return UPB_DESCRIPTOR_TYPE_SFIXED32;
-        case UPB_INTFMT_ZIGZAG:   return UPB_DESCRIPTOR_TYPE_SINT32;
-      }
-    case UPB_TYPE_INT64:
-      switch (upb_fielddef_intfmt(f)) {
-        case UPB_INTFMT_VARIABLE: return UPB_DESCRIPTOR_TYPE_INT64;
-        case UPB_INTFMT_FIXED:    return UPB_DESCRIPTOR_TYPE_SFIXED64;
-        case UPB_INTFMT_ZIGZAG:   return UPB_DESCRIPTOR_TYPE_SINT64;
-      }
-    case UPB_TYPE_UINT32:
-      switch (upb_fielddef_intfmt(f)) {
-        case UPB_INTFMT_VARIABLE: return UPB_DESCRIPTOR_TYPE_UINT32;
-        case UPB_INTFMT_FIXED:    return UPB_DESCRIPTOR_TYPE_FIXED32;
-        case UPB_INTFMT_ZIGZAG:   return -1;
-      }
-    case UPB_TYPE_UINT64:
-      switch (upb_fielddef_intfmt(f)) {
-        case UPB_INTFMT_VARIABLE: return UPB_DESCRIPTOR_TYPE_UINT64;
-        case UPB_INTFMT_FIXED:    return UPB_DESCRIPTOR_TYPE_FIXED64;
-        case UPB_INTFMT_ZIGZAG:   return -1;
-      }
-    case UPB_TYPE_MESSAGE:
-      return upb_fielddef_istagdelim(f) ?
-          UPB_DESCRIPTOR_TYPE_GROUP : UPB_DESCRIPTOR_TYPE_MESSAGE;
-  }
-  return 0;
-}
-
-void upb_fielddef_setisextension(upb_fielddef *f, bool is_extension) {
-  assert(!upb_fielddef_isfrozen(f));
-  f->is_extension_ = is_extension;
-}
-
-void upb_fielddef_setlazy(upb_fielddef *f, bool lazy) {
-  assert(!upb_fielddef_isfrozen(f));
-  f->lazy_ = lazy;
-}
-
-void upb_fielddef_setpacked(upb_fielddef *f, bool packed) {
-  assert(!upb_fielddef_isfrozen(f));
-  f->packed_ = packed;
-}
-
-void upb_fielddef_setlabel(upb_fielddef *f, upb_label_t label) {
-  assert(!upb_fielddef_isfrozen(f));
-  assert(upb_fielddef_checklabel(label));
-  f->label_ = label;
-}
-
-void upb_fielddef_setintfmt(upb_fielddef *f, upb_intfmt_t fmt) {
-  assert(!upb_fielddef_isfrozen(f));
-  assert(upb_fielddef_checkintfmt(fmt));
-  f->intfmt = fmt;
-}
-
-void upb_fielddef_settagdelim(upb_fielddef *f, bool tag_delim) {
-  assert(!upb_fielddef_isfrozen(f));
-  f->tagdelim = tag_delim;
-  f->tagdelim = tag_delim;
-}
-
-static bool checksetdefault(upb_fielddef *f, upb_fieldtype_t type) {
-  if (!f->type_is_set_ || upb_fielddef_isfrozen(f) ||
-      upb_fielddef_type(f) != type) {
-    assert(false);
-    return false;
-  }
-  if (f->default_is_string) {
-    str_t *s = f->defaultval.bytes;
-    assert(s || type == UPB_TYPE_ENUM);
-    if (s) freestr(s);
-  }
-  f->default_is_string = false;
-  return true;
-}
-
-void upb_fielddef_setdefaultint64(upb_fielddef *f, int64_t value) {
-  if (checksetdefault(f, UPB_TYPE_INT64))
-    f->defaultval.sint = value;
-}
-
-void upb_fielddef_setdefaultint32(upb_fielddef *f, int32_t value) {
-  if ((upb_fielddef_type(f) == UPB_TYPE_ENUM &&
-       checksetdefault(f, UPB_TYPE_ENUM)) ||
-      checksetdefault(f, UPB_TYPE_INT32)) {
-    f->defaultval.sint = value;
-  }
-}
-
-void upb_fielddef_setdefaultuint64(upb_fielddef *f, uint64_t value) {
-  if (checksetdefault(f, UPB_TYPE_UINT64))
-    f->defaultval.uint = value;
-}
-
-void upb_fielddef_setdefaultuint32(upb_fielddef *f, uint32_t value) {
-  if (checksetdefault(f, UPB_TYPE_UINT32))
-    f->defaultval.uint = value;
-}
-
-void upb_fielddef_setdefaultbool(upb_fielddef *f, bool value) {
-  if (checksetdefault(f, UPB_TYPE_BOOL))
-    f->defaultval.uint = value;
-}
-
-void upb_fielddef_setdefaultfloat(upb_fielddef *f, float value) {
-  if (checksetdefault(f, UPB_TYPE_FLOAT))
-    f->defaultval.flt = value;
-}
-
-void upb_fielddef_setdefaultdouble(upb_fielddef *f, double value) {
-  if (checksetdefault(f, UPB_TYPE_DOUBLE))
-    f->defaultval.dbl = value;
-}
-
-bool upb_fielddef_setdefaultstr(upb_fielddef *f, const void *str, size_t len,
-                                upb_status *s) {
-  str_t *str2;
-  assert(upb_fielddef_isstring(f) || f->type_ == UPB_TYPE_ENUM);
-  if (f->type_ == UPB_TYPE_ENUM && !upb_isident(str, len, false, s))
-    return false;
-
-  if (f->default_is_string) {
-    str_t *s = f->defaultval.bytes;
-    assert(s || f->type_ == UPB_TYPE_ENUM);
-    if (s) freestr(s);
-  } else {
-    assert(f->type_ == UPB_TYPE_ENUM);
-  }
-
-  str2 = newstr(str, len);
-  f->defaultval.bytes = str2;
-  f->default_is_string = true;
-  return true;
-}
-
-void upb_fielddef_setdefaultcstr(upb_fielddef *f, const char *str,
-                                 upb_status *s) {
-  assert(f->type_is_set_);
-  upb_fielddef_setdefaultstr(f, str, str ? strlen(str) : 0, s);
-}
-
-bool upb_fielddef_enumhasdefaultint32(const upb_fielddef *f) {
-  int32_t val;
-  assert(f->type_is_set_ && f->type_ == UPB_TYPE_ENUM);
-  return enumdefaultint32(f, &val);
-}
-
-bool upb_fielddef_enumhasdefaultstr(const upb_fielddef *f) {
-  assert(f->type_is_set_ && f->type_ == UPB_TYPE_ENUM);
-  return enumdefaultstr(f) != NULL;
-}
-
-static bool upb_subdef_typecheck(upb_fielddef *f, const upb_def *subdef,
-                                 upb_status *s) {
-  if (f->type_ == UPB_TYPE_MESSAGE) {
-    if (upb_dyncast_msgdef(subdef)) return true;
-    upb_status_seterrmsg(s, "invalid subdef type for this submessage field");
-    return false;
-  } else if (f->type_ == UPB_TYPE_ENUM) {
-    if (upb_dyncast_enumdef(subdef)) return true;
-    upb_status_seterrmsg(s, "invalid subdef type for this enum field");
-    return false;
-  } else {
-    upb_status_seterrmsg(s, "only message and enum fields can have a subdef");
-    return false;
-  }
-}
-
-static void release_subdef(upb_fielddef *f) {
-  if (f->subdef_is_symbolic) {
-    free(f->sub.name);
-  } else if (f->sub.def) {
-    upb_unref2(f->sub.def, f);
-  }
-}
-
-bool upb_fielddef_setsubdef(upb_fielddef *f, const upb_def *subdef,
-                            upb_status *s) {
-  assert(!upb_fielddef_isfrozen(f));
-  assert(upb_fielddef_hassubdef(f));
-  if (subdef && !upb_subdef_typecheck(f, subdef, s)) return false;
-  release_subdef(f);
-  f->sub.def = subdef;
-  f->subdef_is_symbolic = false;
-  if (f->sub.def) upb_ref2(f->sub.def, f);
-  return true;
-}
-
-bool upb_fielddef_setmsgsubdef(upb_fielddef *f, const upb_msgdef *subdef,
-                               upb_status *s) {
-  return upb_fielddef_setsubdef(f, upb_msgdef_upcast(subdef), s);
-}
-
-bool upb_fielddef_setenumsubdef(upb_fielddef *f, const upb_enumdef *subdef,
-                                upb_status *s) {
-  return upb_fielddef_setsubdef(f, upb_enumdef_upcast(subdef), s);
-}
-
-bool upb_fielddef_setsubdefname(upb_fielddef *f, const char *name,
-                                upb_status *s) {
-  assert(!upb_fielddef_isfrozen(f));
-  if (!upb_fielddef_hassubdef(f)) {
-    upb_status_seterrmsg(s, "field type does not accept a subdef");
-    return false;
-  }
-  /* TODO: validate name (upb_isident() doesn't quite work atm because this name
-   * may have a leading "."). */
-  release_subdef(f);
-  f->sub.name = upb_strdup(name);
-  f->subdef_is_symbolic = true;
-  return true;
-}
-
-bool upb_fielddef_issubmsg(const upb_fielddef *f) {
-  return upb_fielddef_type(f) == UPB_TYPE_MESSAGE;
-}
-
-bool upb_fielddef_isstring(const upb_fielddef *f) {
-  return upb_fielddef_type(f) == UPB_TYPE_STRING ||
-         upb_fielddef_type(f) == UPB_TYPE_BYTES;
-}
-
-bool upb_fielddef_isseq(const upb_fielddef *f) {
-  return upb_fielddef_label(f) == UPB_LABEL_REPEATED;
-}
-
-bool upb_fielddef_isprimitive(const upb_fielddef *f) {
-  return !upb_fielddef_isstring(f) && !upb_fielddef_issubmsg(f);
-}
-
-bool upb_fielddef_ismap(const upb_fielddef *f) {
-  return upb_fielddef_isseq(f) && upb_fielddef_issubmsg(f) &&
-         upb_msgdef_mapentry(upb_fielddef_msgsubdef(f));
-}
-
-bool upb_fielddef_hassubdef(const upb_fielddef *f) {
-  return upb_fielddef_issubmsg(f) || upb_fielddef_type(f) == UPB_TYPE_ENUM;
-}
-
-static bool between(int32_t x, int32_t low, int32_t high) {
-  return x >= low && x <= high;
-}
-
-bool upb_fielddef_checklabel(int32_t label) { return between(label, 1, 3); }
-bool upb_fielddef_checktype(int32_t type) { return between(type, 1, 11); }
-bool upb_fielddef_checkintfmt(int32_t fmt) { return between(fmt, 1, 3); }
-
-bool upb_fielddef_checkdescriptortype(int32_t type) {
-  return between(type, 1, 18);
-}
-
-/* upb_msgdef *****************************************************************/
-
-static void visitmsg(const upb_refcounted *r, upb_refcounted_visit *visit,
-                     void *closure) {
-  upb_msg_oneof_iter o;
-  const upb_msgdef *m = (const upb_msgdef*)r;
-  upb_msg_field_iter i;
-  for(upb_msg_field_begin(&i, m);
-      !upb_msg_field_done(&i);
-      upb_msg_field_next(&i)) {
-    upb_fielddef *f = upb_msg_iter_field(&i);
-    visit(r, upb_fielddef_upcast2(f), closure);
-  }
-  for(upb_msg_oneof_begin(&o, m);
-      !upb_msg_oneof_done(&o);
-      upb_msg_oneof_next(&o)) {
-    upb_oneofdef *f = upb_msg_iter_oneof(&o);
-    visit(r, upb_oneofdef_upcast2(f), closure);
-  }
-}
-
-static void freemsg(upb_refcounted *r) {
-  upb_msgdef *m = (upb_msgdef*)r;
-  upb_strtable_uninit(&m->ntoo);
-  upb_strtable_uninit(&m->ntof);
-  upb_inttable_uninit(&m->itof);
-  upb_def_uninit(upb_msgdef_upcast_mutable(m));
-  free(m);
-}
-
-upb_msgdef *upb_msgdef_new(const void *owner) {
-  static const struct upb_refcounted_vtbl vtbl = {visitmsg, freemsg};
-  upb_msgdef *m = malloc(sizeof(*m));
-  if (!m) return NULL;
-  if (!upb_def_init(upb_msgdef_upcast_mutable(m), UPB_DEF_MSG, &vtbl, owner))
-    goto err2;
-  if (!upb_inttable_init(&m->itof, UPB_CTYPE_PTR)) goto err3;
-  if (!upb_strtable_init(&m->ntof, UPB_CTYPE_PTR)) goto err2;
-  if (!upb_strtable_init(&m->ntoo, UPB_CTYPE_PTR)) goto err1;
-  m->map_entry = false;
-  return m;
-
-err1:
-  upb_strtable_uninit(&m->ntof);
-err2:
-  upb_inttable_uninit(&m->itof);
-err3:
-  free(m);
-  return NULL;
-}
-
-upb_msgdef *upb_msgdef_dup(const upb_msgdef *m, const void *owner) {
-  bool ok;
-  upb_msg_field_iter i;
-  upb_msg_oneof_iter o;
-
-  upb_msgdef *newm = upb_msgdef_new(owner);
-  if (!newm) return NULL;
-  ok = upb_def_setfullname(upb_msgdef_upcast_mutable(newm),
-                           upb_def_fullname(upb_msgdef_upcast(m)),
-                           NULL);
-  newm->map_entry = m->map_entry;
-  UPB_ASSERT_VAR(ok, ok);
-  for(upb_msg_field_begin(&i, m);
-      !upb_msg_field_done(&i);
-      upb_msg_field_next(&i)) {
-    upb_fielddef *f = upb_fielddef_dup(upb_msg_iter_field(&i), &f);
-    /* Fields in oneofs are dup'd below. */
-    if (upb_fielddef_containingoneof(f)) continue;
-    if (!f || !upb_msgdef_addfield(newm, f, &f, NULL)) {
-      upb_msgdef_unref(newm, owner);
-      return NULL;
-    }
-  }
-  for(upb_msg_oneof_begin(&o, m);
-      !upb_msg_oneof_done(&o);
-      upb_msg_oneof_next(&o)) {
-    upb_oneofdef *f = upb_oneofdef_dup(upb_msg_iter_oneof(&o), &f);
-    if (!f || !upb_msgdef_addoneof(newm, f, &f, NULL)) {
-      upb_msgdef_unref(newm, owner);
-      return NULL;
-    }
-  }
-  return newm;
-}
-
-bool upb_msgdef_freeze(upb_msgdef *m, upb_status *status) {
-  upb_def *d = upb_msgdef_upcast_mutable(m);
-  return upb_def_freeze(&d, 1, status);
-}
-
-const char *upb_msgdef_fullname(const upb_msgdef *m) {
-  return upb_def_fullname(upb_msgdef_upcast(m));
-}
-
-bool upb_msgdef_setfullname(upb_msgdef *m, const char *fullname,
-                            upb_status *s) {
-  return upb_def_setfullname(upb_msgdef_upcast_mutable(m), fullname, s);
-}
-
-/* Helper: check that the field |f| is safe to add to msgdef |m|. Set an error
- * on status |s| and return false if not. */
-static bool check_field_add(const upb_msgdef *m, const upb_fielddef *f,
-                            upb_status *s) {
-  if (upb_fielddef_containingtype(f) != NULL) {
-    upb_status_seterrmsg(s, "fielddef already belongs to a message");
-    return false;
-  } else if (upb_fielddef_name(f) == NULL || upb_fielddef_number(f) == 0) {
-    upb_status_seterrmsg(s, "field name or number were not set");
-    return false;
-  } else if (upb_msgdef_ntofz(m, upb_fielddef_name(f)) ||
-             upb_msgdef_itof(m, upb_fielddef_number(f))) {
-    upb_status_seterrmsg(s, "duplicate field name or number for field");
-    return false;
-  }
-  return true;
-}
-
-static void add_field(upb_msgdef *m, upb_fielddef *f, const void *ref_donor) {
-  release_containingtype(f);
-  f->msg.def = m;
-  f->msg_is_symbolic = false;
-  upb_inttable_insert(&m->itof, upb_fielddef_number(f), upb_value_ptr(f));
-  upb_strtable_insert(&m->ntof, upb_fielddef_name(f), upb_value_ptr(f));
-  upb_ref2(f, m);
-  upb_ref2(m, f);
-  if (ref_donor) upb_fielddef_unref(f, ref_donor);
-}
-
-bool upb_msgdef_addfield(upb_msgdef *m, upb_fielddef *f, const void *ref_donor,
-                         upb_status *s) {
-  /* TODO: extensions need to have a separate namespace, because proto2 allows a
-   * top-level extension (ie. one not in any package) to have the same name as a
-   * field from the message.
-   *
-   * This also implies that there needs to be a separate lookup-by-name method
-   * for extensions.  It seems desirable for iteration to return both extensions
-   * and non-extensions though.
-   *
-   * We also need to validate that the field number is in an extension range iff
-   * it is an extension.
-   *
-   * This method is idempotent. Check if |f| is already part of this msgdef and
-   * return immediately if so. */
-  if (upb_fielddef_containingtype(f) == m) {
-    return true;
-  }
-
-  /* Check constraints for all fields before performing any action. */
-  if (!check_field_add(m, f, s)) {
-    return false;
-  } else if (upb_fielddef_containingoneof(f) != NULL) {
-    /* Fields in a oneof can only be added by adding the oneof to the msgdef. */
-    upb_status_seterrmsg(s, "fielddef is part of a oneof");
-    return false;
-  }
-
-  /* Constraint checks ok, perform the action. */
-  add_field(m, f, ref_donor);
-  return true;
-}
-
-bool upb_msgdef_addoneof(upb_msgdef *m, upb_oneofdef *o, const void *ref_donor,
-                         upb_status *s) {
-  upb_oneof_iter it;
-
-  /* Check various conditions that would prevent this oneof from being added. */
-  if (upb_oneofdef_containingtype(o)) {
-    upb_status_seterrmsg(s, "oneofdef already belongs to a message");
-    return false;
-  } else if (upb_oneofdef_name(o) == NULL) {
-    upb_status_seterrmsg(s, "oneofdef name was not set");
-    return false;
-  } else if (upb_msgdef_ntooz(m, upb_oneofdef_name(o))) {
-    upb_status_seterrmsg(s, "duplicate oneof name");
-    return false;
-  }
-
-  /* Check that all of the oneof's fields do not conflict with names or numbers
-   * of fields already in the message. */
-  for (upb_oneof_begin(&it, o); !upb_oneof_done(&it); upb_oneof_next(&it)) {
-    const upb_fielddef *f = upb_oneof_iter_field(&it);
-    if (!check_field_add(m, f, s)) {
-      return false;
-    }
-  }
-
-  /* Everything checks out -- commit now. */
-
-  /* Add oneof itself first. */
-  o->parent = m;
-  upb_strtable_insert(&m->ntoo, upb_oneofdef_name(o), upb_value_ptr(o));
-  upb_ref2(o, m);
-  upb_ref2(m, o);
-
-  /* Add each field of the oneof directly to the msgdef. */
-  for (upb_oneof_begin(&it, o); !upb_oneof_done(&it); upb_oneof_next(&it)) {
-    upb_fielddef *f = upb_oneof_iter_field(&it);
-    add_field(m, f, NULL);
-  }
-
-  if (ref_donor) upb_oneofdef_unref(o, ref_donor);
-
-  return true;
-}
-
-const upb_fielddef *upb_msgdef_itof(const upb_msgdef *m, uint32_t i) {
-  upb_value val;
-  return upb_inttable_lookup32(&m->itof, i, &val) ?
-      upb_value_getptr(val) : NULL;
-}
-
-const upb_fielddef *upb_msgdef_ntof(const upb_msgdef *m, const char *name,
-                                    size_t len) {
-  upb_value val;
-  return upb_strtable_lookup2(&m->ntof, name, len, &val) ?
-      upb_value_getptr(val) : NULL;
-}
-
-const upb_oneofdef *upb_msgdef_ntoo(const upb_msgdef *m, const char *name,
-                                    size_t len) {
-  upb_value val;
-  return upb_strtable_lookup2(&m->ntoo, name, len, &val) ?
-      upb_value_getptr(val) : NULL;
-}
-
-int upb_msgdef_numfields(const upb_msgdef *m) {
-  return upb_strtable_count(&m->ntof);
-}
-
-int upb_msgdef_numoneofs(const upb_msgdef *m) {
-  return upb_strtable_count(&m->ntoo);
-}
-
-void upb_msgdef_setmapentry(upb_msgdef *m, bool map_entry) {
-  assert(!upb_msgdef_isfrozen(m));
-  m->map_entry = map_entry;
-}
-
-bool upb_msgdef_mapentry(const upb_msgdef *m) {
-  return m->map_entry;
-}
-
-void upb_msg_field_begin(upb_msg_field_iter *iter, const upb_msgdef *m) {
-  upb_inttable_begin(iter, &m->itof);
-}
-
-void upb_msg_field_next(upb_msg_field_iter *iter) { upb_inttable_next(iter); }
-
-bool upb_msg_field_done(const upb_msg_field_iter *iter) {
-  return upb_inttable_done(iter);
-}
-
-upb_fielddef *upb_msg_iter_field(const upb_msg_field_iter *iter) {
-  return (upb_fielddef*)upb_value_getptr(upb_inttable_iter_value(iter));
-}
-
-void upb_msg_field_iter_setdone(upb_msg_field_iter *iter) {
-  upb_inttable_iter_setdone(iter);
-}
-
-void upb_msg_oneof_begin(upb_msg_oneof_iter *iter, const upb_msgdef *m) {
-  upb_strtable_begin(iter, &m->ntoo);
-}
-
-void upb_msg_oneof_next(upb_msg_oneof_iter *iter) { upb_strtable_next(iter); }
-
-bool upb_msg_oneof_done(const upb_msg_oneof_iter *iter) {
-  return upb_strtable_done(iter);
-}
-
-upb_oneofdef *upb_msg_iter_oneof(const upb_msg_oneof_iter *iter) {
-  return (upb_oneofdef*)upb_value_getptr(upb_strtable_iter_value(iter));
-}
-
-void upb_msg_oneof_iter_setdone(upb_msg_oneof_iter *iter) {
-  upb_strtable_iter_setdone(iter);
-}
-
-/* upb_oneofdef ***************************************************************/
-
-static void visitoneof(const upb_refcounted *r, upb_refcounted_visit *visit,
-                       void *closure) {
-  const upb_oneofdef *o = (const upb_oneofdef*)r;
-  upb_oneof_iter i;
-  for (upb_oneof_begin(&i, o); !upb_oneof_done(&i); upb_oneof_next(&i)) {
-    const upb_fielddef *f = upb_oneof_iter_field(&i);
-    visit(r, upb_fielddef_upcast2(f), closure);
-  }
-  if (o->parent) {
-    visit(r, upb_msgdef_upcast2(o->parent), closure);
-  }
-}
-
-static void freeoneof(upb_refcounted *r) {
-  upb_oneofdef *o = (upb_oneofdef*)r;
-  upb_strtable_uninit(&o->ntof);
-  upb_inttable_uninit(&o->itof);
-  upb_def_uninit(upb_oneofdef_upcast_mutable(o));
-  free(o);
-}
-
-upb_oneofdef *upb_oneofdef_new(const void *owner) {
-  static const struct upb_refcounted_vtbl vtbl = {visitoneof, freeoneof};
-  upb_oneofdef *o = malloc(sizeof(*o));
-  o->parent = NULL;
-  if (!o) return NULL;
-  if (!upb_def_init(upb_oneofdef_upcast_mutable(o), UPB_DEF_ONEOF, &vtbl,
-                    owner))
-    goto err2;
-  if (!upb_inttable_init(&o->itof, UPB_CTYPE_PTR)) goto err2;
-  if (!upb_strtable_init(&o->ntof, UPB_CTYPE_PTR)) goto err1;
-  return o;
-
-err1:
-  upb_inttable_uninit(&o->itof);
-err2:
-  free(o);
-  return NULL;
-}
-
-upb_oneofdef *upb_oneofdef_dup(const upb_oneofdef *o, const void *owner) {
-  bool ok;
-  upb_oneof_iter i;
-  upb_oneofdef *newo = upb_oneofdef_new(owner);
-  if (!newo) return NULL;
-  ok = upb_def_setfullname(upb_oneofdef_upcast_mutable(newo),
-                           upb_def_fullname(upb_oneofdef_upcast(o)), NULL);
-  UPB_ASSERT_VAR(ok, ok);
-  for (upb_oneof_begin(&i, o); !upb_oneof_done(&i); upb_oneof_next(&i)) {
-    upb_fielddef *f = upb_fielddef_dup(upb_oneof_iter_field(&i), &f);
-    if (!f || !upb_oneofdef_addfield(newo, f, &f, NULL)) {
-      upb_oneofdef_unref(newo, owner);
-      return NULL;
-    }
-  }
-  return newo;
-}
-
-const char *upb_oneofdef_name(const upb_oneofdef *o) {
-  return upb_def_fullname(upb_oneofdef_upcast(o));
-}
-
-bool upb_oneofdef_setname(upb_oneofdef *o, const char *fullname,
-                             upb_status *s) {
-  if (upb_oneofdef_containingtype(o)) {
-    upb_status_seterrmsg(s, "oneof already added to a message");
-    return false;
-  }
-  return upb_def_setfullname(upb_oneofdef_upcast_mutable(o), fullname, s);
-}
-
-const upb_msgdef *upb_oneofdef_containingtype(const upb_oneofdef *o) {
-  return o->parent;
-}
-
-int upb_oneofdef_numfields(const upb_oneofdef *o) {
-  return upb_strtable_count(&o->ntof);
-}
-
-bool upb_oneofdef_addfield(upb_oneofdef *o, upb_fielddef *f,
-                           const void *ref_donor,
-                           upb_status *s) {
-  assert(!upb_oneofdef_isfrozen(o));
-  assert(!o->parent || !upb_msgdef_isfrozen(o->parent));
-
-  /* This method is idempotent. Check if |f| is already part of this oneofdef
-   * and return immediately if so. */
-  if (upb_fielddef_containingoneof(f) == o) {
-    return true;
-  }
-
-  /* The field must have an OPTIONAL label. */
-  if (upb_fielddef_label(f) != UPB_LABEL_OPTIONAL) {
-    upb_status_seterrmsg(s, "fields in oneof must have OPTIONAL label");
-    return false;
-  }
-
-  /* Check that no field with this name or number exists already in the oneof.
-   * Also check that the field is not already part of a oneof. */
-  if (upb_fielddef_name(f) == NULL || upb_fielddef_number(f) == 0) {
-    upb_status_seterrmsg(s, "field name or number were not set");
-    return false;
-  } else if (upb_oneofdef_itof(o, upb_fielddef_number(f)) ||
-             upb_oneofdef_ntofz(o, upb_fielddef_name(f))) {
-    upb_status_seterrmsg(s, "duplicate field name or number");
-    return false;
-  } else if (upb_fielddef_containingoneof(f) != NULL) {
-    upb_status_seterrmsg(s, "fielddef already belongs to a oneof");
-    return false;
-  }
-
-  /* We allow adding a field to the oneof either if the field is not part of a
-   * msgdef, or if it is and we are also part of the same msgdef. */
-  if (o->parent == NULL) {
-    /* If we're not in a msgdef, the field cannot be either. Otherwise we would
-     * need to magically add this oneof to a msgdef to remain consistent, which
-     * is surprising behavior. */
-    if (upb_fielddef_containingtype(f) != NULL) {
-      upb_status_seterrmsg(s, "fielddef already belongs to a message, but "
-                              "oneof does not");
-      return false;
-    }
-  } else {
-    /* If we're in a msgdef, the user can add fields that either aren't in any
-     * msgdef (in which case they're added to our msgdef) or already a part of
-     * our msgdef. */
-    if (upb_fielddef_containingtype(f) != NULL &&
-        upb_fielddef_containingtype(f) != o->parent) {
-      upb_status_seterrmsg(s, "fielddef belongs to a different message "
-                              "than oneof");
-      return false;
-    }
-  }
-
-  /* Commit phase. First add the field to our parent msgdef, if any, because
-   * that may fail; then add the field to our own tables. */
-
-  if (o->parent != NULL && upb_fielddef_containingtype(f) == NULL) {
-    if (!upb_msgdef_addfield((upb_msgdef*)o->parent, f, NULL, s)) {
-      return false;
-    }
-  }
-
-  release_containingtype(f);
-  f->oneof = o;
-  upb_inttable_insert(&o->itof, upb_fielddef_number(f), upb_value_ptr(f));
-  upb_strtable_insert(&o->ntof, upb_fielddef_name(f), upb_value_ptr(f));
-  upb_ref2(f, o);
-  upb_ref2(o, f);
-  if (ref_donor) upb_fielddef_unref(f, ref_donor);
-
-  return true;
-}
-
-const upb_fielddef *upb_oneofdef_ntof(const upb_oneofdef *o,
-                                      const char *name, size_t length) {
-  upb_value val;
-  return upb_strtable_lookup2(&o->ntof, name, length, &val) ?
-      upb_value_getptr(val) : NULL;
-}
-
-const upb_fielddef *upb_oneofdef_itof(const upb_oneofdef *o, uint32_t num) {
-  upb_value val;
-  return upb_inttable_lookup32(&o->itof, num, &val) ?
-      upb_value_getptr(val) : NULL;
-}
-
-void upb_oneof_begin(upb_oneof_iter *iter, const upb_oneofdef *o) {
-  upb_inttable_begin(iter, &o->itof);
-}
-
-void upb_oneof_next(upb_oneof_iter *iter) {
-  upb_inttable_next(iter);
-}
-
-bool upb_oneof_done(upb_oneof_iter *iter) {
-  return upb_inttable_done(iter);
-}
-
-upb_fielddef *upb_oneof_iter_field(const upb_oneof_iter *iter) {
-  return (upb_fielddef*)upb_value_getptr(upb_inttable_iter_value(iter));
-}
-
-void upb_oneof_iter_setdone(upb_oneof_iter *iter) {
-  upb_inttable_iter_setdone(iter);
-}
-
-
-#include <stdlib.h>
-#include <stdio.h>
-#include <string.h>
-
-typedef struct cleanup_ent {
-  upb_cleanup_func *cleanup;
-  void *ud;
-  struct cleanup_ent *next;
-} cleanup_ent;
-
-static void *seeded_alloc(void *ud, void *ptr, size_t oldsize, size_t size);
-
-/* Default allocator **********************************************************/
-
-/* Just use realloc, keeping all allocated blocks in a linked list to destroy at
- * the end. */
-
-typedef struct mem_block {
-  /* List is doubly-linked, because in cases where realloc() moves an existing
-   * block, we need to be able to remove the old pointer from the list
-   * efficiently. */
-  struct mem_block *prev, *next;
-#ifndef NDEBUG
-  size_t size;  /* Doesn't include mem_block structure. */
-#endif
-} mem_block;
-
-typedef struct {
-  mem_block *head;
-} default_alloc_ud;
-
-static void *default_alloc(void *_ud, void *ptr, size_t oldsize, size_t size) {
-  default_alloc_ud *ud = _ud;
-  mem_block *from, *block;
-  void *ret;
-  UPB_UNUSED(oldsize);
-
-  from = ptr ? (void*)((char*)ptr - sizeof(mem_block)) : NULL;
-
-#ifndef NDEBUG
-  if (from) {
-    assert(oldsize <= from->size);
-  }
-#endif
-
-  /* TODO(haberman): we probably need to provide even better alignment here,
-   * like 16-byte alignment of the returned data pointer. */
-  block = realloc(from, size + sizeof(mem_block));
-  if (!block) return NULL;
-  ret = (char*)block + sizeof(*block);
-
-#ifndef NDEBUG
-  block->size = size;
-#endif
-
-  if (from) {
-    if (block != from) {
-      /* The block was moved, so pointers in next and prev blocks must be
-       * updated to its new location. */
-      if (block->next) block->next->prev = block;
-      if (block->prev) block->prev->next = block;
-      if (ud->head == from) ud->head = block;
-    }
-  } else {
-    /* Insert at head of linked list. */
-    block->prev = NULL;
-    block->next = ud->head;
-    if (block->next) block->next->prev = block;
-    ud->head = block;
-  }
-
-  return ret;
-}
-
-static void default_alloc_cleanup(void *_ud) {
-  default_alloc_ud *ud = _ud;
-  mem_block *block = ud->head;
-
-  while (block) {
-    void *to_free = block;
-    block = block->next;
-    free(to_free);
-  }
-}
-
-
-/* Standard error functions ***************************************************/
-
-static bool default_err(void *ud, const upb_status *status) {
-  UPB_UNUSED(ud);
-  UPB_UNUSED(status);
-  return false;
-}
-
-static bool write_err_to(void *ud, const upb_status *status) {
-  upb_status *copy_to = ud;
-  upb_status_copy(copy_to, status);
-  return false;
-}
-
-
-/* upb_env ********************************************************************/
-
-void upb_env_init(upb_env *e) {
-  default_alloc_ud *ud = (default_alloc_ud*)&e->default_alloc_ud;
-  e->ok_ = true;
-  e->bytes_allocated = 0;
-  e->cleanup_head = NULL;
-
-  ud->head = NULL;
-
-  /* Set default functions. */
-  upb_env_setallocfunc(e, default_alloc, ud);
-  upb_env_seterrorfunc(e, default_err, NULL);
-}
-
-void upb_env_uninit(upb_env *e) {
-  cleanup_ent *ent = e->cleanup_head;
-
-  while (ent) {
-    ent->cleanup(ent->ud);
-    ent = ent->next;
-  }
-
-  /* Must do this after running cleanup functions, because this will delete
-     the memory we store our cleanup entries in! */
-  if (e->alloc == default_alloc) {
-    default_alloc_cleanup(e->alloc_ud);
-  }
-}
-
-UPB_FORCEINLINE void upb_env_setallocfunc(upb_env *e, upb_alloc_func *alloc,
-                                          void *ud) {
-  e->alloc = alloc;
-  e->alloc_ud = ud;
-}
-
-UPB_FORCEINLINE void upb_env_seterrorfunc(upb_env *e, upb_error_func *func,
-                                          void *ud) {
-  e->err = func;
-  e->err_ud = ud;
-}
-
-void upb_env_reporterrorsto(upb_env *e, upb_status *status) {
-  e->err = write_err_to;
-  e->err_ud = status;
-}
-
-bool upb_env_ok(const upb_env *e) {
-  return e->ok_;
-}
-
-bool upb_env_reporterror(upb_env *e, const upb_status *status) {
-  e->ok_ = false;
-  return e->err(e->err_ud, status);
-}
-
-bool upb_env_addcleanup(upb_env *e, upb_cleanup_func *func, void *ud) {
-  cleanup_ent *ent = upb_env_malloc(e, sizeof(cleanup_ent));
-  if (!ent) return false;
-
-  ent->cleanup = func;
-  ent->ud = ud;
-  ent->next = e->cleanup_head;
-  e->cleanup_head = ent;
-
-  return true;
-}
-
-void *upb_env_malloc(upb_env *e, size_t size) {
-  e->bytes_allocated += size;
-  if (e->alloc == seeded_alloc) {
-    /* This is equivalent to the next branch, but allows inlining for a
-     * measurable perf benefit. */
-    return seeded_alloc(e->alloc_ud, NULL, 0, size);
-  } else {
-    return e->alloc(e->alloc_ud, NULL, 0, size);
-  }
-}
-
-void *upb_env_realloc(upb_env *e, void *ptr, size_t oldsize, size_t size) {
-  char *ret;
-  assert(oldsize <= size);
-  ret = e->alloc(e->alloc_ud, ptr, oldsize, size);
-
-#ifndef NDEBUG
-  /* Overwrite non-preserved memory to ensure callers are passing the oldsize
-   * that they truly require. */
-  memset(ret + oldsize, 0xff, size - oldsize);
-#endif
-
-  return ret;
-}
-
-size_t upb_env_bytesallocated(const upb_env *e) {
-  return e->bytes_allocated;
-}
-
-
-/* upb_seededalloc ************************************************************/
-
-/* Be conservative and choose 16 in case anyone is using SSE. */
-static const size_t maxalign = 16;
-
-static size_t align_up(size_t size) {
-  return ((size + maxalign - 1) / maxalign) * maxalign;
-}
-
-UPB_FORCEINLINE static void *seeded_alloc(void *ud, void *ptr, size_t oldsize,
-                                          size_t size) {
-  upb_seededalloc *a = ud;
-
-  size = align_up(size);
-
-  assert(a->mem_limit >= a->mem_ptr);
-
-  if (oldsize == 0 && size <= (size_t)(a->mem_limit - a->mem_ptr)) {
-    /* Fast path: we can satisfy from the initial allocation. */
-    void *ret = a->mem_ptr;
-    a->mem_ptr += size;
-    return ret;
-  } else {
-    char *chptr = ptr;
-    /* Slow path: fallback to other allocator. */
-    a->need_cleanup = true;
-    /* Is `ptr` part of the user-provided initial block? Don't pass it to the
-     * default allocator if so; otherwise, it may try to realloc() the block. */
-    if (chptr >= a->mem_base && chptr < a->mem_limit) {
-      void *ret;
-      assert(chptr + oldsize <= a->mem_limit);
-      ret = a->alloc(a->alloc_ud, NULL, 0, size);
-      if (ret) memcpy(ret, ptr, oldsize);
-      return ret;
-    } else {
-      return a->alloc(a->alloc_ud, ptr, oldsize, size);
-    }
-  }
-}
-
-void upb_seededalloc_init(upb_seededalloc *a, void *mem, size_t len) {
-  default_alloc_ud *ud = (default_alloc_ud*)&a->default_alloc_ud;
-  a->mem_base = mem;
-  a->mem_ptr = mem;
-  a->mem_limit = (char*)mem + len;
-  a->need_cleanup = false;
-  a->returned_allocfunc = false;
-
-  ud->head = NULL;
-
-  upb_seededalloc_setfallbackalloc(a, default_alloc, ud);
-}
-
-void upb_seededalloc_uninit(upb_seededalloc *a) {
-  if (a->alloc == default_alloc && a->need_cleanup) {
-    default_alloc_cleanup(a->alloc_ud);
-  }
-}
-
-UPB_FORCEINLINE void upb_seededalloc_setfallbackalloc(upb_seededalloc *a,
-                                                      upb_alloc_func *alloc,
-                                                      void *ud) {
-  assert(!a->returned_allocfunc);
-  a->alloc = alloc;
-  a->alloc_ud = ud;
-}
-
-upb_alloc_func *upb_seededalloc_getallocfunc(upb_seededalloc *a) {
-  a->returned_allocfunc = true;
-  return seeded_alloc;
-}
-/*
-** TODO(haberman): it's unclear whether a lot of the consistency checks should
-** assert() or return false.
-*/
-
-
-#include <stdlib.h>
-#include <string.h>
-
-
-
-/* Defined for the sole purpose of having a unique pointer value for
- * UPB_NO_CLOSURE. */
-char _upb_noclosure;
-
-static void freehandlers(upb_refcounted *r) {
-  upb_handlers *h = (upb_handlers*)r;
-
-  upb_inttable_iter i;
-  upb_inttable_begin(&i, &h->cleanup_);
-  for(; !upb_inttable_done(&i); upb_inttable_next(&i)) {
-    void *val = (void*)upb_inttable_iter_key(&i);
-    upb_value func_val = upb_inttable_iter_value(&i);
-    upb_handlerfree *func = upb_value_getfptr(func_val);
-    func(val);
-  }
-
-  upb_inttable_uninit(&h->cleanup_);
-  upb_msgdef_unref(h->msg, h);
-  free(h->sub);
-  free(h);
-}
-
-static void visithandlers(const upb_refcounted *r, upb_refcounted_visit *visit,
-                          void *closure) {
-  const upb_handlers *h = (const upb_handlers*)r;
-  upb_msg_field_iter i;
-  for(upb_msg_field_begin(&i, h->msg);
-      !upb_msg_field_done(&i);
-      upb_msg_field_next(&i)) {
-    upb_fielddef *f = upb_msg_iter_field(&i);
-    const upb_handlers *sub;
-    if (!upb_fielddef_issubmsg(f)) continue;
-    sub = upb_handlers_getsubhandlers(h, f);
-    if (sub) visit(r, upb_handlers_upcast(sub), closure);
-  }
-}
-
-static const struct upb_refcounted_vtbl vtbl = {visithandlers, freehandlers};
-
-typedef struct {
-  upb_inttable tab;  /* maps upb_msgdef* -> upb_handlers*. */
-  upb_handlers_callback *callback;
-  const void *closure;
-} dfs_state;
-
-/* TODO(haberman): discard upb_handlers* objects that do not actually have any
- * handlers set and cannot reach any upb_handlers* object that does.  This is
- * slightly tricky to do correctly. */
-static upb_handlers *newformsg(const upb_msgdef *m, const void *owner,
-                               dfs_state *s) {
-  upb_msg_field_iter i;
-  upb_handlers *h = upb_handlers_new(m, owner);
-  if (!h) return NULL;
-  if (!upb_inttable_insertptr(&s->tab, m, upb_value_ptr(h))) goto oom;
-
-  s->callback(s->closure, h);
-
-  /* For each submessage field, get or create a handlers object and set it as
-   * the subhandlers. */
-  for(upb_msg_field_begin(&i, m);
-      !upb_msg_field_done(&i);
-      upb_msg_field_next(&i)) {
-    upb_fielddef *f = upb_msg_iter_field(&i);
-    const upb_msgdef *subdef;
-    upb_value subm_ent;
-
-    if (!upb_fielddef_issubmsg(f)) continue;
-
-    subdef = upb_downcast_msgdef(upb_fielddef_subdef(f));
-    if (upb_inttable_lookupptr(&s->tab, subdef, &subm_ent)) {
-      upb_handlers_setsubhandlers(h, f, upb_value_getptr(subm_ent));
-    } else {
-      upb_handlers *sub_mh = newformsg(subdef, &sub_mh, s);
-      if (!sub_mh) goto oom;
-      upb_handlers_setsubhandlers(h, f, sub_mh);
-      upb_handlers_unref(sub_mh, &sub_mh);
-    }
-  }
-  return h;
-
-oom:
-  upb_handlers_unref(h, owner);
-  return NULL;
-}
-
-/* Given a selector for a STARTSUBMSG handler, resolves to a pointer to the
- * subhandlers for this submessage field. */
-#define SUBH(h, selector) (h->sub[selector])
-
-/* The selector for a submessage field is the field index. */
-#define SUBH_F(h, f) SUBH(h, f->index_)
-
-static int32_t trygetsel(upb_handlers *h, const upb_fielddef *f,
-                         upb_handlertype_t type) {
-  upb_selector_t sel;
-  assert(!upb_handlers_isfrozen(h));
-  if (upb_handlers_msgdef(h) != upb_fielddef_containingtype(f)) {
-    upb_status_seterrf(
-        &h->status_, "type mismatch: field %s does not belong to message %s",
-        upb_fielddef_name(f), upb_msgdef_fullname(upb_handlers_msgdef(h)));
-    return -1;
-  }
-  if (!upb_handlers_getselector(f, type, &sel)) {
-    upb_status_seterrf(
-        &h->status_,
-        "type mismatch: cannot register handler type %d for field %s",
-        type, upb_fielddef_name(f));
-    return -1;
-  }
-  return sel;
-}
-
-static upb_selector_t handlers_getsel(upb_handlers *h, const upb_fielddef *f,
-                             upb_handlertype_t type) {
-  int32_t sel = trygetsel(h, f, type);
-  assert(sel >= 0);
-  return sel;
-}
-
-static const void **returntype(upb_handlers *h, const upb_fielddef *f,
-                               upb_handlertype_t type) {
-  return &h->table[handlers_getsel(h, f, type)].attr.return_closure_type_;
-}
-
-static bool doset(upb_handlers *h, int32_t sel, const upb_fielddef *f,
-                  upb_handlertype_t type, upb_func *func,
-                  upb_handlerattr *attr) {
-  upb_handlerattr set_attr = UPB_HANDLERATTR_INITIALIZER;
-  const void *closure_type;
-  const void **context_closure_type;
-
-  assert(!upb_handlers_isfrozen(h));
-
-  if (sel < 0) {
-    upb_status_seterrmsg(&h->status_,
-                         "incorrect handler type for this field.");
-    return false;
-  }
-
-  if (h->table[sel].func) {
-    upb_status_seterrmsg(&h->status_,
-                         "cannot change handler once it has been set.");
-    return false;
-  }
-
-  if (attr) {
-    set_attr = *attr;
-  }
-
-  /* Check that the given closure type matches the closure type that has been
-   * established for this context (if any). */
-  closure_type = upb_handlerattr_closuretype(&set_attr);
-
-  if (type == UPB_HANDLER_STRING) {
-    context_closure_type = returntype(h, f, UPB_HANDLER_STARTSTR);
-  } else if (f && upb_fielddef_isseq(f) &&
-             type != UPB_HANDLER_STARTSEQ &&
-             type != UPB_HANDLER_ENDSEQ) {
-    context_closure_type = returntype(h, f, UPB_HANDLER_STARTSEQ);
-  } else {
-    context_closure_type = &h->top_closure_type;
-  }
-
-  if (closure_type && *context_closure_type &&
-      closure_type != *context_closure_type) {
-    /* TODO(haberman): better message for debugging. */
-    if (f) {
-      upb_status_seterrf(&h->status_,
-                         "closure type does not match for field %s",
-                         upb_fielddef_name(f));
-    } else {
-      upb_status_seterrmsg(
-          &h->status_, "closure type does not match for message-level handler");
-    }
-    return false;
-  }
-
-  if (closure_type)
-    *context_closure_type = closure_type;
-
-  /* If this is a STARTSEQ or STARTSTR handler, check that the returned pointer
-   * matches any pre-existing expectations about what type is expected. */
-  if (type == UPB_HANDLER_STARTSEQ || type == UPB_HANDLER_STARTSTR) {
-    const void *return_type = upb_handlerattr_returnclosuretype(&set_attr);
-    const void *table_return_type =
-        upb_handlerattr_returnclosuretype(&h->table[sel].attr);
-    if (return_type && table_return_type && return_type != table_return_type) {
-      upb_status_seterrmsg(&h->status_, "closure return type does not match");
-      return false;
-    }
-
-    if (table_return_type && !return_type)
-      upb_handlerattr_setreturnclosuretype(&set_attr, table_return_type);
-  }
-
-  h->table[sel].func = (upb_func*)func;
-  h->table[sel].attr = set_attr;
-  return true;
-}
-
-/* Returns the effective closure type for this handler (which will propagate
- * from outer frames if this frame has no START* handler).  Not implemented for
- * UPB_HANDLER_STRING at the moment since this is not needed.  Returns NULL is
- * the effective closure type is unspecified (either no handler was registered
- * to specify it or the handler that was registered did not specify the closure
- * type). */
-const void *effective_closure_type(upb_handlers *h, const upb_fielddef *f,
-                                   upb_handlertype_t type) {
-  const void *ret;
-  upb_selector_t sel;
-
-  assert(type != UPB_HANDLER_STRING);
-  ret = h->top_closure_type;
-
-  if (upb_fielddef_isseq(f) &&
-      type != UPB_HANDLER_STARTSEQ &&
-      type != UPB_HANDLER_ENDSEQ &&
-      h->table[sel = handlers_getsel(h, f, UPB_HANDLER_STARTSEQ)].func) {
-    ret = upb_handlerattr_returnclosuretype(&h->table[sel].attr);
-  }
-
-  if (type == UPB_HANDLER_STRING &&
-      h->table[sel = handlers_getsel(h, f, UPB_HANDLER_STARTSTR)].func) {
-    ret = upb_handlerattr_returnclosuretype(&h->table[sel].attr);
-  }
-
-  /* The effective type of the submessage; not used yet.
-   * if (type == SUBMESSAGE &&
-   *     h->table[sel = handlers_getsel(h, f, UPB_HANDLER_STARTSUBMSG)].func) {
-   *   ret = upb_handlerattr_returnclosuretype(&h->table[sel].attr);
-   * } */
-
-  return ret;
-}
-
-/* Checks whether the START* handler specified by f & type is missing even
- * though it is required to convert the established type of an outer frame
- * ("closure_type") into the established type of an inner frame (represented in
- * the return closure type of this handler's attr. */
-bool checkstart(upb_handlers *h, const upb_fielddef *f, upb_handlertype_t type,
-                upb_status *status) {
-  const void *closure_type;
-  const upb_handlerattr *attr;
-  const void *return_closure_type;
-
-  upb_selector_t sel = handlers_getsel(h, f, type);
-  if (h->table[sel].func) return true;
-  closure_type = effective_closure_type(h, f, type);
-  attr = &h->table[sel].attr;
-  return_closure_type = upb_handlerattr_returnclosuretype(attr);
-  if (closure_type && return_closure_type &&
-      closure_type != return_closure_type) {
-    upb_status_seterrf(status,
-                       "expected start handler to return sub type for field %f",
-                       upb_fielddef_name(f));
-    return false;
-  }
-  return true;
-}
-
-/* Public interface ***********************************************************/
-
-upb_handlers *upb_handlers_new(const upb_msgdef *md, const void *owner) {
-  int extra;
-  upb_handlers *h;
-
-  assert(upb_msgdef_isfrozen(md));
-
-  extra = sizeof(upb_handlers_tabent) * (md->selector_count - 1);
-  h = calloc(sizeof(*h) + extra, 1);
-  if (!h) return NULL;
-
-  h->msg = md;
-  upb_msgdef_ref(h->msg, h);
-  upb_status_clear(&h->status_);
-  h->sub = calloc(md->submsg_field_count, sizeof(*h->sub));
-  if (!h->sub) goto oom;
-  if (!upb_refcounted_init(upb_handlers_upcast_mutable(h), &vtbl, owner))
-    goto oom;
-  if (!upb_inttable_init(&h->cleanup_, UPB_CTYPE_FPTR)) goto oom;
-
-  /* calloc() above initialized all handlers to NULL. */
-  return h;
-
-oom:
-  freehandlers(upb_handlers_upcast_mutable(h));
-  return NULL;
-}
-
-const upb_handlers *upb_handlers_newfrozen(const upb_msgdef *m,
-                                           const void *owner,
-                                           upb_handlers_callback *callback,
-                                           const void *closure) {
-  dfs_state state;
-  upb_handlers *ret;
-  bool ok;
-  upb_refcounted *r;
-
-  state.callback = callback;
-  state.closure = closure;
-  if (!upb_inttable_init(&state.tab, UPB_CTYPE_PTR)) return NULL;
-
-  ret = newformsg(m, owner, &state);
-
-  upb_inttable_uninit(&state.tab);
-  if (!ret) return NULL;
-
-  r = upb_handlers_upcast_mutable(ret);
-  ok = upb_refcounted_freeze(&r, 1, NULL, UPB_MAX_HANDLER_DEPTH);
-  UPB_ASSERT_VAR(ok, ok);
-
-  return ret;
-}
-
-const upb_status *upb_handlers_status(upb_handlers *h) {
-  assert(!upb_handlers_isfrozen(h));
-  return &h->status_;
-}
-
-void upb_handlers_clearerr(upb_handlers *h) {
-  assert(!upb_handlers_isfrozen(h));
-  upb_status_clear(&h->status_);
-}
-
-#define SETTER(name, handlerctype, handlertype) \
-  bool upb_handlers_set ## name(upb_handlers *h, const upb_fielddef *f, \
-                                handlerctype func, upb_handlerattr *attr) { \
-    int32_t sel = trygetsel(h, f, handlertype); \
-    return doset(h, sel, f, handlertype, (upb_func*)func, attr); \
-  }
-
-SETTER(int32,       upb_int32_handlerfunc*,       UPB_HANDLER_INT32)
-SETTER(int64,       upb_int64_handlerfunc*,       UPB_HANDLER_INT64)
-SETTER(uint32,      upb_uint32_handlerfunc*,      UPB_HANDLER_UINT32)
-SETTER(uint64,      upb_uint64_handlerfunc*,      UPB_HANDLER_UINT64)
-SETTER(float,       upb_float_handlerfunc*,       UPB_HANDLER_FLOAT)
-SETTER(double,      upb_double_handlerfunc*,      UPB_HANDLER_DOUBLE)
-SETTER(bool,        upb_bool_handlerfunc*,        UPB_HANDLER_BOOL)
-SETTER(startstr,    upb_startstr_handlerfunc*,    UPB_HANDLER_STARTSTR)
-SETTER(string,      upb_string_handlerfunc*,      UPB_HANDLER_STRING)
-SETTER(endstr,      upb_endfield_handlerfunc*,    UPB_HANDLER_ENDSTR)
-SETTER(startseq,    upb_startfield_handlerfunc*,  UPB_HANDLER_STARTSEQ)
-SETTER(startsubmsg, upb_startfield_handlerfunc*,  UPB_HANDLER_STARTSUBMSG)
-SETTER(endsubmsg,   upb_endfield_handlerfunc*,    UPB_HANDLER_ENDSUBMSG)
-SETTER(endseq,      upb_endfield_handlerfunc*,    UPB_HANDLER_ENDSEQ)
-
-#undef SETTER
-
-bool upb_handlers_setstartmsg(upb_handlers *h, upb_startmsg_handlerfunc *func,
-                              upb_handlerattr *attr) {
-  return doset(h, UPB_STARTMSG_SELECTOR, NULL, UPB_HANDLER_INT32,
-               (upb_func *)func, attr);
-}
-
-bool upb_handlers_setendmsg(upb_handlers *h, upb_endmsg_handlerfunc *func,
-                            upb_handlerattr *attr) {
-  assert(!upb_handlers_isfrozen(h));
-  return doset(h, UPB_ENDMSG_SELECTOR, NULL, UPB_HANDLER_INT32,
-               (upb_func *)func, attr);
-}
-
-bool upb_handlers_setsubhandlers(upb_handlers *h, const upb_fielddef *f,
-                                 const upb_handlers *sub) {
-  assert(sub);
-  assert(!upb_handlers_isfrozen(h));
-  assert(upb_fielddef_issubmsg(f));
-  if (SUBH_F(h, f)) return false;  /* Can't reset. */
-  if (upb_msgdef_upcast(upb_handlers_msgdef(sub)) != upb_fielddef_subdef(f)) {
-    return false;
-  }
-  SUBH_F(h, f) = sub;
-  upb_ref2(sub, h);
-  return true;
-}
-
-const upb_handlers *upb_handlers_getsubhandlers(const upb_handlers *h,
-                                                const upb_fielddef *f) {
-  assert(upb_fielddef_issubmsg(f));
-  return SUBH_F(h, f);
-}
-
-bool upb_handlers_getattr(const upb_handlers *h, upb_selector_t sel,
-                          upb_handlerattr *attr) {
-  if (!upb_handlers_gethandler(h, sel))
-    return false;
-  *attr = h->table[sel].attr;
-  return true;
-}
-
-const upb_handlers *upb_handlers_getsubhandlers_sel(const upb_handlers *h,
-                                                    upb_selector_t sel) {
-  /* STARTSUBMSG selector in sel is the field's selector base. */
-  return SUBH(h, sel - UPB_STATIC_SELECTOR_COUNT);
-}
-
-const upb_msgdef *upb_handlers_msgdef(const upb_handlers *h) { return h->msg; }
-
-bool upb_handlers_addcleanup(upb_handlers *h, void *p, upb_handlerfree *func) {
-  bool ok;
-  if (upb_inttable_lookupptr(&h->cleanup_, p, NULL)) {
-    return false;
-  }
-  ok = upb_inttable_insertptr(&h->cleanup_, p, upb_value_fptr(func));
-  UPB_ASSERT_VAR(ok, ok);
-  return true;
-}
-
-
-/* "Static" methods ***********************************************************/
-
-bool upb_handlers_freeze(upb_handlers *const*handlers, int n, upb_status *s) {
-  /* TODO: verify we have a transitive closure. */
-  int i;
-  for (i = 0; i < n; i++) {
-    upb_msg_field_iter j;
-    upb_handlers *h = handlers[i];
-
-    if (!upb_ok(&h->status_)) {
-      upb_status_seterrf(s, "handlers for message %s had error status: %s",
-                         upb_msgdef_fullname(upb_handlers_msgdef(h)),
-                         upb_status_errmsg(&h->status_));
-      return false;
-    }
-
-    /* Check that there are no closure mismatches due to missing Start* handlers
-     * or subhandlers with different type-level types. */
-    for(upb_msg_field_begin(&j, h->msg);
-        !upb_msg_field_done(&j);
-        upb_msg_field_next(&j)) {
-
-      const upb_fielddef *f = upb_msg_iter_field(&j);
-      if (upb_fielddef_isseq(f)) {
-        if (!checkstart(h, f, UPB_HANDLER_STARTSEQ, s))
-          return false;
-      }
-
-      if (upb_fielddef_isstring(f)) {
-        if (!checkstart(h, f, UPB_HANDLER_STARTSTR, s))
-          return false;
-      }
-
-      if (upb_fielddef_issubmsg(f)) {
-        bool hashandler = false;
-        if (upb_handlers_gethandler(
-                h, handlers_getsel(h, f, UPB_HANDLER_STARTSUBMSG)) ||
-            upb_handlers_gethandler(
-                h, handlers_getsel(h, f, UPB_HANDLER_ENDSUBMSG))) {
-          hashandler = true;
-        }
-
-        if (upb_fielddef_isseq(f) &&
-            (upb_handlers_gethandler(
-                 h, handlers_getsel(h, f, UPB_HANDLER_STARTSEQ)) ||
-             upb_handlers_gethandler(
-                 h, handlers_getsel(h, f, UPB_HANDLER_ENDSEQ)))) {
-          hashandler = true;
-        }
-
-        if (hashandler && !upb_handlers_getsubhandlers(h, f)) {
-          /* For now we add an empty subhandlers in this case.  It makes the
-           * decoder code generator simpler, because it only has to handle two
-           * cases (submessage has handlers or not) as opposed to three
-           * (submessage has handlers in enclosing message but no subhandlers).
-           *
-           * This makes parsing less efficient in the case that we want to
-           * notice a submessage but skip its contents (like if we're testing
-           * for submessage presence or counting the number of repeated
-           * submessages).  In this case we will end up parsing the submessage
-           * field by field and throwing away the results for each, instead of
-           * skipping the whole delimited thing at once.  If this is an issue we
-           * can revisit it, but do remember that this only arises when you have
-           * handlers (startseq/startsubmsg/endsubmsg/endseq) set for the
-           * submessage but no subhandlers.  The uses cases for this are
-           * limited. */
-          upb_handlers *sub = upb_handlers_new(upb_fielddef_msgsubdef(f), &sub);
-          upb_handlers_setsubhandlers(h, f, sub);
-          upb_handlers_unref(sub, &sub);
-        }
-
-        /* TODO(haberman): check type of submessage.
-         * This is slightly tricky; also consider whether we should check that
-         * they match at setsubhandlers time. */
-      }
-    }
-  }
-
-  if (!upb_refcounted_freeze((upb_refcounted*const*)handlers, n, s,
-                             UPB_MAX_HANDLER_DEPTH)) {
-    return false;
-  }
-
-  return true;
-}
-
-upb_handlertype_t upb_handlers_getprimitivehandlertype(const upb_fielddef *f) {
-  switch (upb_fielddef_type(f)) {
-    case UPB_TYPE_INT32:
-    case UPB_TYPE_ENUM: return UPB_HANDLER_INT32;
-    case UPB_TYPE_INT64: return UPB_HANDLER_INT64;
-    case UPB_TYPE_UINT32: return UPB_HANDLER_UINT32;
-    case UPB_TYPE_UINT64: return UPB_HANDLER_UINT64;
-    case UPB_TYPE_FLOAT: return UPB_HANDLER_FLOAT;
-    case UPB_TYPE_DOUBLE: return UPB_HANDLER_DOUBLE;
-    case UPB_TYPE_BOOL: return UPB_HANDLER_BOOL;
-    default: assert(false); return -1;  /* Invalid input. */
-  }
-}
-
-bool upb_handlers_getselector(const upb_fielddef *f, upb_handlertype_t type,
-                              upb_selector_t *s) {
-  switch (type) {
-    case UPB_HANDLER_INT32:
-    case UPB_HANDLER_INT64:
-    case UPB_HANDLER_UINT32:
-    case UPB_HANDLER_UINT64:
-    case UPB_HANDLER_FLOAT:
-    case UPB_HANDLER_DOUBLE:
-    case UPB_HANDLER_BOOL:
-      if (!upb_fielddef_isprimitive(f) ||
-          upb_handlers_getprimitivehandlertype(f) != type)
-        return false;
-      *s = f->selector_base;
-      break;
-    case UPB_HANDLER_STRING:
-      if (upb_fielddef_isstring(f)) {
-        *s = f->selector_base;
-      } else if (upb_fielddef_lazy(f)) {
-        *s = f->selector_base + 3;
-      } else {
-        return false;
-      }
-      break;
-    case UPB_HANDLER_STARTSTR:
-      if (upb_fielddef_isstring(f) || upb_fielddef_lazy(f)) {
-        *s = f->selector_base + 1;
-      } else {
-        return false;
-      }
-      break;
-    case UPB_HANDLER_ENDSTR:
-      if (upb_fielddef_isstring(f) || upb_fielddef_lazy(f)) {
-        *s = f->selector_base + 2;
-      } else {
-        return false;
-      }
-      break;
-    case UPB_HANDLER_STARTSEQ:
-      if (!upb_fielddef_isseq(f)) return false;
-      *s = f->selector_base - 2;
-      break;
-    case UPB_HANDLER_ENDSEQ:
-      if (!upb_fielddef_isseq(f)) return false;
-      *s = f->selector_base - 1;
-      break;
-    case UPB_HANDLER_STARTSUBMSG:
-      if (!upb_fielddef_issubmsg(f)) return false;
-      /* Selectors for STARTSUBMSG are at the beginning of the table so that the
-       * selector can also be used as an index into the "sub" array of
-       * subhandlers.  The indexes for the two into these two tables are the
-       * same, except that in the handler table the static selectors come first. */
-      *s = f->index_ + UPB_STATIC_SELECTOR_COUNT;
-      break;
-    case UPB_HANDLER_ENDSUBMSG:
-      if (!upb_fielddef_issubmsg(f)) return false;
-      *s = f->selector_base;
-      break;
-  }
-  assert((size_t)*s < upb_fielddef_containingtype(f)->selector_count);
-  return true;
-}
-
-uint32_t upb_handlers_selectorbaseoffset(const upb_fielddef *f) {
-  return upb_fielddef_isseq(f) ? 2 : 0;
-}
-
-uint32_t upb_handlers_selectorcount(const upb_fielddef *f) {
-  uint32_t ret = 1;
-  if (upb_fielddef_isseq(f)) ret += 2;    /* STARTSEQ/ENDSEQ */
-  if (upb_fielddef_isstring(f)) ret += 2; /* [STRING]/STARTSTR/ENDSTR */
-  if (upb_fielddef_issubmsg(f)) {
-    /* ENDSUBMSG (STARTSUBMSG is at table beginning) */
-    ret += 0;
-    if (upb_fielddef_lazy(f)) {
-      /* STARTSTR/ENDSTR/STRING (for lazy) */
-      ret += 3;
-    }
-  }
-  return ret;
-}
-
-
-/* upb_handlerattr ************************************************************/
-
-void upb_handlerattr_init(upb_handlerattr *attr) {
-  upb_handlerattr from = UPB_HANDLERATTR_INITIALIZER;
-  memcpy(attr, &from, sizeof(*attr));
-}
-
-void upb_handlerattr_uninit(upb_handlerattr *attr) {
-  UPB_UNUSED(attr);
-}
-
-bool upb_handlerattr_sethandlerdata(upb_handlerattr *attr, const void *hd) {
-  attr->handler_data_ = hd;
-  return true;
-}
-
-bool upb_handlerattr_setclosuretype(upb_handlerattr *attr, const void *type) {
-  attr->closure_type_ = type;
-  return true;
-}
-
-const void *upb_handlerattr_closuretype(const upb_handlerattr *attr) {
-  return attr->closure_type_;
-}
-
-bool upb_handlerattr_setreturnclosuretype(upb_handlerattr *attr,
-                                          const void *type) {
-  attr->return_closure_type_ = type;
-  return true;
-}
-
-const void *upb_handlerattr_returnclosuretype(const upb_handlerattr *attr) {
-  return attr->return_closure_type_;
-}
-
-bool upb_handlerattr_setalwaysok(upb_handlerattr *attr, bool alwaysok) {
-  attr->alwaysok_ = alwaysok;
-  return true;
-}
-
-bool upb_handlerattr_alwaysok(const upb_handlerattr *attr) {
-  return attr->alwaysok_;
-}
-
-/* upb_bufhandle **************************************************************/
-
-size_t upb_bufhandle_objofs(const upb_bufhandle *h) {
-  return h->objofs_;
-}
-
-/* upb_byteshandler ***********************************************************/
-
-void upb_byteshandler_init(upb_byteshandler* h) {
-  memset(h, 0, sizeof(*h));
-}
-
-/* For when we support handlerfree callbacks. */
-void upb_byteshandler_uninit(upb_byteshandler* h) {
-  UPB_UNUSED(h);
-}
-
-bool upb_byteshandler_setstartstr(upb_byteshandler *h,
-                                  upb_startstr_handlerfunc *func, void *d) {
-  h->table[UPB_STARTSTR_SELECTOR].func = (upb_func*)func;
-  h->table[UPB_STARTSTR_SELECTOR].attr.handler_data_ = d;
-  return true;
-}
-
-bool upb_byteshandler_setstring(upb_byteshandler *h,
-                                upb_string_handlerfunc *func, void *d) {
-  h->table[UPB_STRING_SELECTOR].func = (upb_func*)func;
-  h->table[UPB_STRING_SELECTOR].attr.handler_data_ = d;
-  return true;
-}
-
-bool upb_byteshandler_setendstr(upb_byteshandler *h,
-                                upb_endfield_handlerfunc *func, void *d) {
-  h->table[UPB_ENDSTR_SELECTOR].func = (upb_func*)func;
-  h->table[UPB_ENDSTR_SELECTOR].attr.handler_data_ = d;
-  return true;
-}
-/*
-** upb::RefCounted Implementation
-**
-** Our key invariants are:
-** 1. reference cycles never span groups
-** 2. for ref2(to, from), we increment to's count iff group(from) != group(to)
-**
-** The previous two are how we avoid leaking cycles.  Other important
-** invariants are:
-** 3. for mutable objects "from" and "to", if there exists a ref2(to, from)
-**    this implies group(from) == group(to).  (In practice, what we implement
-**    is even stronger; "from" and "to" will share a group if there has *ever*
-**    been a ref2(to, from), but all that is necessary for correctness is the
-**    weaker one).
-** 4. mutable and immutable objects are never in the same group.
-*/
-
-
-#include <setjmp.h>
-#include <stdlib.h>
-
-static void freeobj(upb_refcounted *o);
-
-const char untracked_val;
-const void *UPB_UNTRACKED_REF = &untracked_val;
-
-/* arch-specific atomic primitives  *******************************************/
-
-#ifdef UPB_THREAD_UNSAFE /*---------------------------------------------------*/
-
-static void atomic_inc(uint32_t *a) { (*a)++; }
-static bool atomic_dec(uint32_t *a) { return --(*a) == 0; }
-
-#elif defined(__GNUC__) || defined(__clang__) /*------------------------------*/
-
-static void atomic_inc(uint32_t *a) { __sync_fetch_and_add(a, 1); }
-static bool atomic_dec(uint32_t *a) { return __sync_sub_and_fetch(a, 1) == 0; }
-
-#elif defined(WIN32) /*-------------------------------------------------------*/
-
-#include <Windows.h>
-
-static void atomic_inc(upb_atomic_t *a) { InterlockedIncrement(&a->val); }
-static bool atomic_dec(upb_atomic_t *a) {
-  return InterlockedDecrement(&a->val) == 0;
-}
-
-#else
-#error Atomic primitives not defined for your platform/CPU.  \
-       Implement them or compile with UPB_THREAD_UNSAFE.
-#endif
-
-/* All static objects point to this refcount.
- * It is special-cased in ref/unref below.  */
-uint32_t static_refcount = -1;
-
-/* We can avoid atomic ops for statically-declared objects.
- * This is a minor optimization but nice since we can avoid degrading under
- * contention in this case. */
-
-static void refgroup(uint32_t *group) {
-  if (group != &static_refcount)
-    atomic_inc(group);
-}
-
-static bool unrefgroup(uint32_t *group) {
-  if (group == &static_refcount) {
-    return false;
-  } else {
-    return atomic_dec(group);
-  }
-}
-
-
-/* Reference tracking (debug only) ********************************************/
-
-#ifdef UPB_DEBUG_REFS
-
-#ifdef UPB_THREAD_UNSAFE
-
-static void upb_lock() {}
-static void upb_unlock() {}
-
-#else
-
-/* User must define functions that lock/unlock a global mutex and link this
- * file against them. */
-void upb_lock();
-void upb_unlock();
-
-#endif
-
-/* UPB_DEBUG_REFS mode counts on being able to malloc() memory in some
- * code-paths that can normally never fail, like upb_refcounted_ref().  Since
- * we have no way to propagage out-of-memory errors back to the user, and since
- * these errors can only occur in UPB_DEBUG_REFS mode, we immediately fail. */
-#define CHECK_OOM(predicate) if (!(predicate)) { assert(predicate); exit(1); }
-
-typedef struct {
-  int count;  /* How many refs there are (duplicates only allowed for ref2). */
-  bool is_ref2;
-} trackedref;
-
-static trackedref *trackedref_new(bool is_ref2) {
-  trackedref *ret = malloc(sizeof(*ret));
-  CHECK_OOM(ret);
-  ret->count = 1;
-  ret->is_ref2 = is_ref2;
-  return ret;
-}
-
-static void track(const upb_refcounted *r, const void *owner, bool ref2) {
-  upb_value v;
-
-  assert(owner);
-  if (owner == UPB_UNTRACKED_REF) return;
-
-  upb_lock();
-  if (upb_inttable_lookupptr(r->refs, owner, &v)) {
-    trackedref *ref = upb_value_getptr(v);
-    /* Since we allow multiple ref2's for the same to/from pair without
-     * allocating separate memory for each one, we lose the fine-grained
-     * tracking behavior we get with regular refs.  Since ref2s only happen
-     * inside upb, we'll accept this limitation until/unless there is a really
-     * difficult upb-internal bug that can't be figured out without it. */
-    assert(ref2);
-    assert(ref->is_ref2);
-    ref->count++;
-  } else {
-    trackedref *ref = trackedref_new(ref2);
-    bool ok = upb_inttable_insertptr(r->refs, owner, upb_value_ptr(ref));
-    CHECK_OOM(ok);
-    if (ref2) {
-      /* We know this cast is safe when it is a ref2, because it's coming from
-       * another refcounted object. */
-      const upb_refcounted *from = owner;
-      assert(!upb_inttable_lookupptr(from->ref2s, r, NULL));
-      ok = upb_inttable_insertptr(from->ref2s, r, upb_value_ptr(NULL));
-      CHECK_OOM(ok);
-    }
-  }
-  upb_unlock();
-}
-
-static void untrack(const upb_refcounted *r, const void *owner, bool ref2) {
-  upb_value v;
-  bool found;
-  trackedref *ref;
-
-  assert(owner);
-  if (owner == UPB_UNTRACKED_REF) return;
-
-  upb_lock();
-  found = upb_inttable_lookupptr(r->refs, owner, &v);
-  /* This assert will fail if an owner attempts to release a ref it didn't have. */
-  UPB_ASSERT_VAR(found, found);
-  ref = upb_value_getptr(v);
-  assert(ref->is_ref2 == ref2);
-  if (--ref->count == 0) {
-    free(ref);
-    upb_inttable_removeptr(r->refs, owner, NULL);
-    if (ref2) {
-      /* We know this cast is safe when it is a ref2, because it's coming from
-       * another refcounted object. */
-      const upb_refcounted *from = owner;
-      bool removed = upb_inttable_removeptr(from->ref2s, r, NULL);
-      assert(removed);
-    }
-  }
-  upb_unlock();
-}
-
-static void checkref(const upb_refcounted *r, const void *owner, bool ref2) {
-  upb_value v;
-  bool found;
-  trackedref *ref;
-
-  upb_lock();
-  found = upb_inttable_lookupptr(r->refs, owner, &v);
-  UPB_ASSERT_VAR(found, found);
-  ref = upb_value_getptr(v);
-  assert(ref->is_ref2 == ref2);
-  upb_unlock();
-}
-
-/* Populates the given UPB_CTYPE_INT32 inttable with counts of ref2's that
- * originate from the given owner. */
-static void getref2s(const upb_refcounted *owner, upb_inttable *tab) {
-  upb_inttable_iter i;
-
-  upb_lock();
-  upb_inttable_begin(&i, owner->ref2s);
-  for(; !upb_inttable_done(&i); upb_inttable_next(&i)) {
-    upb_value v;
-    upb_value count;
-    trackedref *ref;
-    bool ok;
-    bool found;
-
-    upb_refcounted *to = (upb_refcounted*)upb_inttable_iter_key(&i);
-
-    /* To get the count we need to look in the target's table. */
-    found = upb_inttable_lookupptr(to->refs, owner, &v);
-    assert(found);
-    ref = upb_value_getptr(v);
-    count = upb_value_int32(ref->count);
-
-    ok = upb_inttable_insertptr(tab, to, count);
-    CHECK_OOM(ok);
-  }
-  upb_unlock();
-}
-
-typedef struct {
-  upb_inttable ref2;
-  const upb_refcounted *obj;
-} check_state;
-
-static void visit_check(const upb_refcounted *obj, const upb_refcounted *subobj,
-                        void *closure) {
-  check_state *s = closure;
-  upb_inttable *ref2 = &s->ref2;
-  upb_value v;
-  bool removed;
-  int32_t newcount;
-
-  assert(obj == s->obj);
-  assert(subobj);
-  removed = upb_inttable_removeptr(ref2, subobj, &v);
-  /* The following assertion will fail if the visit() function visits a subobj
-   * that it did not have a ref2 on, or visits the same subobj too many times. */
-  assert(removed);
-  newcount = upb_value_getint32(v) - 1;
-  if (newcount > 0) {
-    upb_inttable_insert(ref2, (uintptr_t)subobj, upb_value_int32(newcount));
-  }
-}
-
-static void visit(const upb_refcounted *r, upb_refcounted_visit *v,
-                  void *closure) {
-  bool ok;
-
-  /* In DEBUG_REFS mode we know what existing ref2 refs there are, so we know
-   * exactly the set of nodes that visit() should visit.  So we verify visit()'s
-   * correctness here. */
-  check_state state;
-  state.obj = r;
-  ok = upb_inttable_init(&state.ref2, UPB_CTYPE_INT32);
-  CHECK_OOM(ok);
-  getref2s(r, &state.ref2);
-
-  /* This should visit any children in the ref2 table. */
-  if (r->vtbl->visit) r->vtbl->visit(r, visit_check, &state);
-
-  /* This assertion will fail if the visit() function missed any children. */
-  assert(upb_inttable_count(&state.ref2) == 0);
-  upb_inttable_uninit(&state.ref2);
-  if (r->vtbl->visit) r->vtbl->visit(r, v, closure);
-}
-
-static bool trackinit(upb_refcounted *r) {
-  r->refs = malloc(sizeof(*r->refs));
-  r->ref2s = malloc(sizeof(*r->ref2s));
-  if (!r->refs || !r->ref2s) goto err1;
-
-  if (!upb_inttable_init(r->refs, UPB_CTYPE_PTR)) goto err1;
-  if (!upb_inttable_init(r->ref2s, UPB_CTYPE_PTR)) goto err2;
-  return true;
-
-err2:
-  upb_inttable_uninit(r->refs);
-err1:
-  free(r->refs);
-  free(r->ref2s);
-  return false;
-}
-
-static void trackfree(const upb_refcounted *r) {
-  upb_inttable_uninit(r->refs);
-  upb_inttable_uninit(r->ref2s);
-  free(r->refs);
-  free(r->ref2s);
-}
-
-#else
-
-static void track(const upb_refcounted *r, const void *owner, bool ref2) {
-  UPB_UNUSED(r);
-  UPB_UNUSED(owner);
-  UPB_UNUSED(ref2);
-}
-
-static void untrack(const upb_refcounted *r, const void *owner, bool ref2) {
-  UPB_UNUSED(r);
-  UPB_UNUSED(owner);
-  UPB_UNUSED(ref2);
-}
-
-static void checkref(const upb_refcounted *r, const void *owner, bool ref2) {
-  UPB_UNUSED(r);
-  UPB_UNUSED(owner);
-  UPB_UNUSED(ref2);
-}
-
-static bool trackinit(upb_refcounted *r) {
-  UPB_UNUSED(r);
-  return true;
-}
-
-static void trackfree(const upb_refcounted *r) {
-  UPB_UNUSED(r);
-}
-
-static void visit(const upb_refcounted *r, upb_refcounted_visit *v,
-                  void *closure) {
-  if (r->vtbl->visit) r->vtbl->visit(r, v, closure);
-}
-
-#endif  /* UPB_DEBUG_REFS */
-
-
-/* freeze() *******************************************************************/
-
-/* The freeze() operation is by far the most complicated part of this scheme.
- * We compute strongly-connected components and then mutate the graph such that
- * we preserve the invariants documented at the top of this file.  And we must
- * handle out-of-memory errors gracefully (without leaving the graph
- * inconsistent), which adds to the fun. */
-
-/* The state used by the freeze operation (shared across many functions). */
-typedef struct {
-  int depth;
-  int maxdepth;
-  uint64_t index;
-  /* Maps upb_refcounted* -> attributes (color, etc).  attr layout varies by
-   * color. */
-  upb_inttable objattr;
-  upb_inttable stack;   /* stack of upb_refcounted* for Tarjan's algorithm. */
-  upb_inttable groups;  /* array of uint32_t*, malloc'd refcounts for new groups */
-  upb_status *status;
-  jmp_buf err;
-} tarjan;
-
-static void release_ref2(const upb_refcounted *obj,
-                         const upb_refcounted *subobj,
-                         void *closure);
-
-/* Node attributes -----------------------------------------------------------*/
-
-/* After our analysis phase all nodes will be either GRAY or WHITE. */
-
-typedef enum {
-  BLACK = 0,  /* Object has not been seen. */
-  GRAY,   /* Object has been found via a refgroup but may not be reachable. */
-  GREEN,  /* Object is reachable and is currently on the Tarjan stack. */
-  WHITE   /* Object is reachable and has been assigned a group (SCC). */
-} color_t;
-
-UPB_NORETURN static void err(tarjan *t) { longjmp(t->err, 1); }
-UPB_NORETURN static void oom(tarjan *t) {
-  upb_status_seterrmsg(t->status, "out of memory");
-  err(t);
-}
-
-static uint64_t trygetattr(const tarjan *t, const upb_refcounted *r) {
-  upb_value v;
-  return upb_inttable_lookupptr(&t->objattr, r, &v) ?
-      upb_value_getuint64(v) : 0;
-}
-
-static uint64_t getattr(const tarjan *t, const upb_refcounted *r) {
-  upb_value v;
-  bool found = upb_inttable_lookupptr(&t->objattr, r, &v);
-  UPB_ASSERT_VAR(found, found);
-  return upb_value_getuint64(v);
-}
-
-static void setattr(tarjan *t, const upb_refcounted *r, uint64_t attr) {
-  upb_inttable_removeptr(&t->objattr, r, NULL);
-  upb_inttable_insertptr(&t->objattr, r, upb_value_uint64(attr));
-}
-
-static color_t color(tarjan *t, const upb_refcounted *r) {
-  return trygetattr(t, r) & 0x3;  /* Color is always stored in the low 2 bits. */
-}
-
-static void set_gray(tarjan *t, const upb_refcounted *r) {
-  assert(color(t, r) == BLACK);
-  setattr(t, r, GRAY);
-}
-
-/* Pushes an obj onto the Tarjan stack and sets it to GREEN. */
-static void push(tarjan *t, const upb_refcounted *r) {
-  assert(color(t, r) == BLACK || color(t, r) == GRAY);
-  /* This defines the attr layout for the GREEN state.  "index" and "lowlink"
-   * get 31 bits, which is plenty (limit of 2B objects frozen at a time). */
-  setattr(t, r, GREEN | (t->index << 2) | (t->index << 33));
-  if (++t->index == 0x80000000) {
-    upb_status_seterrmsg(t->status, "too many objects to freeze");
-    err(t);
-  }
-  upb_inttable_push(&t->stack, upb_value_ptr((void*)r));
-}
-
-/* Pops an obj from the Tarjan stack and sets it to WHITE, with a ptr to its
- * SCC group. */
-static upb_refcounted *pop(tarjan *t) {
-  upb_refcounted *r = upb_value_getptr(upb_inttable_pop(&t->stack));
-  assert(color(t, r) == GREEN);
-  /* This defines the attr layout for nodes in the WHITE state.
-   * Top of group stack is [group, NULL]; we point at group. */
-  setattr(t, r, WHITE | (upb_inttable_count(&t->groups) - 2) << 8);
-  return r;
-}
-
-static void tarjan_newgroup(tarjan *t) {
-  uint32_t *group = malloc(sizeof(*group));
-  if (!group) oom(t);
-  /* Push group and empty group leader (we'll fill in leader later). */
-  if (!upb_inttable_push(&t->groups, upb_value_ptr(group)) ||
-      !upb_inttable_push(&t->groups, upb_value_ptr(NULL))) {
-    free(group);
-    oom(t);
-  }
-  *group = 0;
-}
-
-static uint32_t idx(tarjan *t, const upb_refcounted *r) {
-  assert(color(t, r) == GREEN);
-  return (getattr(t, r) >> 2) & 0x7FFFFFFF;
-}
-
-static uint32_t lowlink(tarjan *t, const upb_refcounted *r) {
-  if (color(t, r) == GREEN) {
-    return getattr(t, r) >> 33;
-  } else {
-    return UINT32_MAX;
-  }
-}
-
-static void set_lowlink(tarjan *t, const upb_refcounted *r, uint32_t lowlink) {
-  assert(color(t, r) == GREEN);
-  setattr(t, r, ((uint64_t)lowlink << 33) | (getattr(t, r) & 0x1FFFFFFFF));
-}
-
-static uint32_t *group(tarjan *t, upb_refcounted *r) {
-  uint64_t groupnum;
-  upb_value v;
-  bool found;
-
-  assert(color(t, r) == WHITE);
-  groupnum = getattr(t, r) >> 8;
-  found = upb_inttable_lookup(&t->groups, groupnum, &v);
-  UPB_ASSERT_VAR(found, found);
-  return upb_value_getptr(v);
-}
-
-/* If the group leader for this object's group has not previously been set,
- * the given object is assigned to be its leader. */
-static upb_refcounted *groupleader(tarjan *t, upb_refcounted *r) {
-  uint64_t leader_slot;
-  upb_value v;
-  bool found;
-
-  assert(color(t, r) == WHITE);
-  leader_slot = (getattr(t, r) >> 8) + 1;
-  found = upb_inttable_lookup(&t->groups, leader_slot, &v);
-  UPB_ASSERT_VAR(found, found);
-  if (upb_value_getptr(v)) {
-    return upb_value_getptr(v);
-  } else {
-    upb_inttable_remove(&t->groups, leader_slot, NULL);
-    upb_inttable_insert(&t->groups, leader_slot, upb_value_ptr(r));
-    return r;
-  }
-}
-
-
-/* Tarjan's algorithm --------------------------------------------------------*/
-
-/* See:
- *   http://en.wikipedia.org/wiki/Tarjan%27s_strongly_connected_components_algorithm */
-static void do_tarjan(const upb_refcounted *obj, tarjan *t);
-
-static void tarjan_visit(const upb_refcounted *obj,
-                         const upb_refcounted *subobj,
-                         void *closure) {
-  tarjan *t = closure;
-  if (++t->depth > t->maxdepth) {
-    upb_status_seterrf(t->status, "graph too deep to freeze (%d)", t->maxdepth);
-    err(t);
-  } else if (subobj->is_frozen || color(t, subobj) == WHITE) {
-    /* Do nothing: we don't want to visit or color already-frozen nodes,
-     * and WHITE nodes have already been assigned a SCC. */
-  } else if (color(t, subobj) < GREEN) {
-    /* Subdef has not yet been visited; recurse on it. */
-    do_tarjan(subobj, t);
-    set_lowlink(t, obj, UPB_MIN(lowlink(t, obj), lowlink(t, subobj)));
-  } else if (color(t, subobj) == GREEN) {
-    /* Subdef is in the stack and hence in the current SCC. */
-    set_lowlink(t, obj, UPB_MIN(lowlink(t, obj), idx(t, subobj)));
-  }
-  --t->depth;
-}
-
-static void do_tarjan(const upb_refcounted *obj, tarjan *t) {
-  if (color(t, obj) == BLACK) {
-    /* We haven't seen this object's group; mark the whole group GRAY. */
-    const upb_refcounted *o = obj;
-    do { set_gray(t, o); } while ((o = o->next) != obj);
-  }
-
-  push(t, obj);
-  visit(obj, tarjan_visit, t);
-  if (lowlink(t, obj) == idx(t, obj)) {
-    tarjan_newgroup(t);
-    while (pop(t) != obj)
-      ;
-  }
-}
-
-
-/* freeze() ------------------------------------------------------------------*/
-
-static void crossref(const upb_refcounted *r, const upb_refcounted *subobj,
-                     void *_t) {
-  tarjan *t = _t;
-  assert(color(t, r) > BLACK);
-  if (color(t, subobj) > BLACK && r->group != subobj->group) {
-    /* Previously this ref was not reflected in subobj->group because they
-     * were in the same group; now that they are split a ref must be taken. */
-    refgroup(subobj->group);
-  }
-}
-
-static bool freeze(upb_refcounted *const*roots, int n, upb_status *s,
-                   int maxdepth) {
-  volatile bool ret = false;
-  int i;
-  upb_inttable_iter iter;
-
-  /* We run in two passes so that we can allocate all memory before performing
-   * any mutation of the input -- this allows us to leave the input unchanged
-   * in the case of memory allocation failure. */
-  tarjan t;
-  t.index = 0;
-  t.depth = 0;
-  t.maxdepth = maxdepth;
-  t.status = s;
-  if (!upb_inttable_init(&t.objattr, UPB_CTYPE_UINT64)) goto err1;
-  if (!upb_inttable_init(&t.stack, UPB_CTYPE_PTR)) goto err2;
-  if (!upb_inttable_init(&t.groups, UPB_CTYPE_PTR)) goto err3;
-  if (setjmp(t.err) != 0) goto err4;
-
-
-  for (i = 0; i < n; i++) {
-    if (color(&t, roots[i]) < GREEN) {
-      do_tarjan(roots[i], &t);
-    }
-  }
-
-  /* If we've made it this far, no further errors are possible so it's safe to
-   * mutate the objects without risk of leaving them in an inconsistent state. */
-  ret = true;
-
-  /* The transformation that follows requires care.  The preconditions are:
-   * - all objects in attr map are WHITE or GRAY, and are in mutable groups
-   *   (groups of all mutable objs)
-   * - no ref2(to, from) refs have incremented count(to) if both "to" and
-   *   "from" are in our attr map (this follows from invariants (2) and (3)) */
-
-  /* Pass 1: we remove WHITE objects from their mutable groups, and add them to
-   * new groups  according to the SCC's we computed.  These new groups will
-   * consist of only frozen objects.  None will be immediately collectible,
-   * because WHITE objects are by definition reachable from one of "roots",
-   * which the caller must own refs on. */
-  upb_inttable_begin(&iter, &t.objattr);
-  for(; !upb_inttable_done(&iter); upb_inttable_next(&iter)) {
-    upb_refcounted *obj = (upb_refcounted*)upb_inttable_iter_key(&iter);
-    /* Since removal from a singly-linked list requires access to the object's
-     * predecessor, we consider obj->next instead of obj for moving.  With the
-     * while() loop we guarantee that we will visit every node's predecessor.
-     * Proof:
-     *  1. every node's predecessor is in our attr map.
-     *  2. though the loop body may change a node's predecessor, it will only
-     *     change it to be the node we are currently operating on, so with a
-     *     while() loop we guarantee ourselves the chance to remove each node. */
-    while (color(&t, obj->next) == WHITE &&
-           group(&t, obj->next) != obj->next->group) {
-      upb_refcounted *leader;
-
-      /* Remove from old group. */
-      upb_refcounted *move = obj->next;
-      if (obj == move) {
-        /* Removing the last object from a group. */
-        assert(*obj->group == obj->individual_count);
-        free(obj->group);
-      } else {
-        obj->next = move->next;
-        /* This may decrease to zero; we'll collect GRAY objects (if any) that
-         * remain in the group in the third pass. */
-        assert(*move->group >= move->individual_count);
-        *move->group -= move->individual_count;
-      }
-
-      /* Add to new group. */
-      leader = groupleader(&t, move);
-      if (move == leader) {
-        /* First object added to new group is its leader. */
-        move->group = group(&t, move);
-        move->next = move;
-        *move->group = move->individual_count;
-      } else {
-        /* Group already has at least one object in it. */
-        assert(leader->group == group(&t, move));
-        move->group = group(&t, move);
-        move->next = leader->next;
-        leader->next = move;
-        *move->group += move->individual_count;
-      }
-
-      move->is_frozen = true;
-    }
-  }
-
-  /* Pass 2: GRAY and WHITE objects "obj" with ref2(to, obj) references must
-   * increment count(to) if group(obj) != group(to) (which could now be the
-   * case if "to" was just frozen). */
-  upb_inttable_begin(&iter, &t.objattr);
-  for(; !upb_inttable_done(&iter); upb_inttable_next(&iter)) {
-    upb_refcounted *obj = (upb_refcounted*)upb_inttable_iter_key(&iter);
-    visit(obj, crossref, &t);
-  }
-
-  /* Pass 3: GRAY objects are collected if their group's refcount dropped to
-   * zero when we removed its white nodes.  This can happen if they had only
-   * been kept alive by virtue of sharing a group with an object that was just
-   * frozen.
-   *
-   * It is important that we do this last, since the GRAY object's free()
-   * function could call unref2() on just-frozen objects, which will decrement
-   * refs that were added in pass 2. */
-  upb_inttable_begin(&iter, &t.objattr);
-  for(; !upb_inttable_done(&iter); upb_inttable_next(&iter)) {
-    upb_refcounted *obj = (upb_refcounted*)upb_inttable_iter_key(&iter);
-    if (obj->group == NULL || *obj->group == 0) {
-      if (obj->group) {
-        upb_refcounted *o;
-
-        /* We eagerly free() the group's count (since we can't easily determine
-         * the group's remaining size it's the easiest way to ensure it gets
-         * done). */
-        free(obj->group);
-
-        /* Visit to release ref2's (done in a separate pass since release_ref2
-         * depends on o->group being unmodified so it can test merged()). */
-        o = obj;
-        do { visit(o, release_ref2, NULL); } while ((o = o->next) != obj);
-
-        /* Mark "group" fields as NULL so we know to free the objects later in
-         * this loop, but also don't try to delete the group twice. */
-        o = obj;
-        do { o->group = NULL; } while ((o = o->next) != obj);
-      }
-      freeobj(obj);
-    }
-  }
-
-err4:
-  if (!ret) {
-    upb_inttable_begin(&iter, &t.groups);
-    for(; !upb_inttable_done(&iter); upb_inttable_next(&iter))
-      free(upb_value_getptr(upb_inttable_iter_value(&iter)));
-  }
-  upb_inttable_uninit(&t.groups);
-err3:
-  upb_inttable_uninit(&t.stack);
-err2:
-  upb_inttable_uninit(&t.objattr);
-err1:
-  return ret;
-}
-
-
-/* Misc internal functions  ***************************************************/
-
-static bool merged(const upb_refcounted *r, const upb_refcounted *r2) {
-  return r->group == r2->group;
-}
-
-static void merge(upb_refcounted *r, upb_refcounted *from) {
-  upb_refcounted *base;
-  upb_refcounted *tmp;
-
-  if (merged(r, from)) return;
-  *r->group += *from->group;
-  free(from->group);
-  base = from;
-
-  /* Set all refcount pointers in the "from" chain to the merged refcount.
-   *
-   * TODO(haberman): this linear algorithm can result in an overall O(n^2) bound
-   * if the user continuously extends a group by one object.  Prevent this by
-   * using one of the techniques in this paper:
-   *     ftp://www.ncedc.org/outgoing/geomorph/dino/orals/p245-tarjan.pdf */
-  do { from->group = r->group; } while ((from = from->next) != base);
-
-  /* Merge the two circularly linked lists by swapping their next pointers. */
-  tmp = r->next;
-  r->next = base->next;
-  base->next = tmp;
-}
-
-static void unref(const upb_refcounted *r);
-
-static void release_ref2(const upb_refcounted *obj,
-                         const upb_refcounted *subobj,
-                         void *closure) {
-  UPB_UNUSED(closure);
-  untrack(subobj, obj, true);
-  if (!merged(obj, subobj)) {
-    assert(subobj->is_frozen);
-    unref(subobj);
-  }
-}
-
-static void unref(const upb_refcounted *r) {
-  if (unrefgroup(r->group)) {
-    const upb_refcounted *o;
-
-    free(r->group);
-
-    /* In two passes, since release_ref2 needs a guarantee that any subobjs
-     * are alive. */
-    o = r;
-    do { visit(o, release_ref2, NULL); } while((o = o->next) != r);
-
-    o = r;
-    do {
-      const upb_refcounted *next = o->next;
-      assert(o->is_frozen || o->individual_count == 0);
-      freeobj((upb_refcounted*)o);
-      o = next;
-    } while(o != r);
-  }
-}
-
-static void freeobj(upb_refcounted *o) {
-  trackfree(o);
-  o->vtbl->free((upb_refcounted*)o);
-}
-
-
-/* Public interface ***********************************************************/
-
-bool upb_refcounted_init(upb_refcounted *r,
-                         const struct upb_refcounted_vtbl *vtbl,
-                         const void *owner) {
-#ifndef NDEBUG
-  /* Endianness check.  This is unrelated to upb_refcounted, it's just a
-   * convenient place to put the check that we can be assured will run for
-   * basically every program using upb. */
-  const int x = 1;
-#ifdef UPB_BIG_ENDIAN
-  assert(*(char*)&x != 1);
-#else
-  assert(*(char*)&x == 1);
-#endif
-#endif
-
-  r->next = r;
-  r->vtbl = vtbl;
-  r->individual_count = 0;
-  r->is_frozen = false;
-  r->group = malloc(sizeof(*r->group));
-  if (!r->group) return false;
-  *r->group = 0;
-  if (!trackinit(r)) {
-    free(r->group);
-    return false;
-  }
-  upb_refcounted_ref(r, owner);
-  return true;
-}
-
-bool upb_refcounted_isfrozen(const upb_refcounted *r) {
-  return r->is_frozen;
-}
-
-void upb_refcounted_ref(const upb_refcounted *r, const void *owner) {
-  track(r, owner, false);
-  if (!r->is_frozen)
-    ((upb_refcounted*)r)->individual_count++;
-  refgroup(r->group);
-}
-
-void upb_refcounted_unref(const upb_refcounted *r, const void *owner) {
-  untrack(r, owner, false);
-  if (!r->is_frozen)
-    ((upb_refcounted*)r)->individual_count--;
-  unref(r);
-}
-
-void upb_refcounted_ref2(const upb_refcounted *r, upb_refcounted *from) {
-  assert(!from->is_frozen);  /* Non-const pointer implies this. */
-  track(r, from, true);
-  if (r->is_frozen) {
-    refgroup(r->group);
-  } else {
-    merge((upb_refcounted*)r, from);
-  }
-}
-
-void upb_refcounted_unref2(const upb_refcounted *r, upb_refcounted *from) {
-  assert(!from->is_frozen);  /* Non-const pointer implies this. */
-  untrack(r, from, true);
-  if (r->is_frozen) {
-    unref(r);
-  } else {
-    assert(merged(r, from));
-  }
-}
-
-void upb_refcounted_donateref(
-    const upb_refcounted *r, const void *from, const void *to) {
-  assert(from != to);
-  if (to != NULL)
-    upb_refcounted_ref(r, to);
-  if (from != NULL)
-    upb_refcounted_unref(r, from);
-}
-
-void upb_refcounted_checkref(const upb_refcounted *r, const void *owner) {
-  checkref(r, owner, false);
-}
-
-bool upb_refcounted_freeze(upb_refcounted *const*roots, int n, upb_status *s,
-                           int maxdepth) {
-  int i;
-  for (i = 0; i < n; i++) {
-    assert(!roots[i]->is_frozen);
-  }
-  return freeze(roots, n, s, maxdepth);
-}
-
-
-#include <stdlib.h>
-
-/* Fallback implementation if the shim is not specialized by the JIT. */
-#define SHIM_WRITER(type, ctype)                                              \
-  bool upb_shim_set ## type (void *c, const void *hd, ctype val) {            \
-    uint8_t *m = c;                                                           \
-    const upb_shim_data *d = hd;                                              \
-    if (d->hasbit > 0)                                                        \
-      *(uint8_t*)&m[d->hasbit / 8] |= 1 << (d->hasbit % 8);                   \
-    *(ctype*)&m[d->offset] = val;                                             \
-    return true;                                                              \
-  }                                                                           \
-
-SHIM_WRITER(double, double)
-SHIM_WRITER(float,  float)
-SHIM_WRITER(int32,  int32_t)
-SHIM_WRITER(int64,  int64_t)
-SHIM_WRITER(uint32, uint32_t)
-SHIM_WRITER(uint64, uint64_t)
-SHIM_WRITER(bool,   bool)
-#undef SHIM_WRITER
-
-bool upb_shim_set(upb_handlers *h, const upb_fielddef *f, size_t offset,
-                  int32_t hasbit) {
-  upb_handlerattr attr = UPB_HANDLERATTR_INITIALIZER;
-  bool ok;
-
-  upb_shim_data *d = malloc(sizeof(*d));
-  if (!d) return false;
-  d->offset = offset;
-  d->hasbit = hasbit;
-
-  upb_handlerattr_sethandlerdata(&attr, d);
-  upb_handlerattr_setalwaysok(&attr, true);
-  upb_handlers_addcleanup(h, d, free);
-
-#define TYPE(u, l) \
-  case UPB_TYPE_##u: \
-    ok = upb_handlers_set##l(h, f, upb_shim_set##l, &attr); break;
-
-  ok = false;
-
-  switch (upb_fielddef_type(f)) {
-    TYPE(INT64,  int64);
-    TYPE(INT32,  int32);
-    TYPE(ENUM,   int32);
-    TYPE(UINT64, uint64);
-    TYPE(UINT32, uint32);
-    TYPE(DOUBLE, double);
-    TYPE(FLOAT,  float);
-    TYPE(BOOL,   bool);
-    default: assert(false); break;
-  }
-#undef TYPE
-
-  upb_handlerattr_uninit(&attr);
-  return ok;
-}
-
-const upb_shim_data *upb_shim_getdata(const upb_handlers *h, upb_selector_t s,
-                                      upb_fieldtype_t *type) {
-  upb_func *f = upb_handlers_gethandler(h, s);
-
-  if ((upb_int64_handlerfunc*)f == upb_shim_setint64) {
-    *type = UPB_TYPE_INT64;
-  } else if ((upb_int32_handlerfunc*)f == upb_shim_setint32) {
-    *type = UPB_TYPE_INT32;
-  } else if ((upb_uint64_handlerfunc*)f == upb_shim_setuint64) {
-    *type = UPB_TYPE_UINT64;
-  } else if ((upb_uint32_handlerfunc*)f == upb_shim_setuint32) {
-    *type = UPB_TYPE_UINT32;
-  } else if ((upb_double_handlerfunc*)f == upb_shim_setdouble) {
-    *type = UPB_TYPE_DOUBLE;
-  } else if ((upb_float_handlerfunc*)f == upb_shim_setfloat) {
-    *type = UPB_TYPE_FLOAT;
-  } else if ((upb_bool_handlerfunc*)f == upb_shim_setbool) {
-    *type = UPB_TYPE_BOOL;
-  } else {
-    return NULL;
-  }
-
-  return (const upb_shim_data*)upb_handlers_gethandlerdata(h, s);
-}
-
-
-#include <stdlib.h>
-#include <string.h>
-
-static void upb_symtab_free(upb_refcounted *r) {
-  upb_symtab *s = (upb_symtab*)r;
-  upb_strtable_iter i;
-  upb_strtable_begin(&i, &s->symtab);
-  for (; !upb_strtable_done(&i); upb_strtable_next(&i)) {
-    const upb_def *def = upb_value_getptr(upb_strtable_iter_value(&i));
-    upb_def_unref(def, s);
-  }
-  upb_strtable_uninit(&s->symtab);
-  free(s);
-}
-
-
-upb_symtab *upb_symtab_new(const void *owner) {
-  static const struct upb_refcounted_vtbl vtbl = {NULL, &upb_symtab_free};
-  upb_symtab *s = malloc(sizeof(*s));
-  upb_refcounted_init(upb_symtab_upcast_mutable(s), &vtbl, owner);
-  upb_strtable_init(&s->symtab, UPB_CTYPE_PTR);
-  return s;
-}
-
-void upb_symtab_freeze(upb_symtab *s) {
-  upb_refcounted *r;
-  bool ok;
-
-  assert(!upb_symtab_isfrozen(s));
-  r = upb_symtab_upcast_mutable(s);
-  /* The symtab does not take ref2's (see refcounted.h) on the defs, because
-   * defs cannot refer back to the table and therefore cannot create cycles.  So
-   * 0 will suffice for maxdepth here. */
-  ok = upb_refcounted_freeze(&r, 1, NULL, 0);
-  UPB_ASSERT_VAR(ok, ok);
-}
-
-const upb_def *upb_symtab_lookup(const upb_symtab *s, const char *sym) {
-  upb_value v;
-  upb_def *ret = upb_strtable_lookup(&s->symtab, sym, &v) ?
-      upb_value_getptr(v) : NULL;
-  return ret;
-}
-
-const upb_msgdef *upb_symtab_lookupmsg(const upb_symtab *s, const char *sym) {
-  upb_value v;
-  upb_def *def = upb_strtable_lookup(&s->symtab, sym, &v) ?
-      upb_value_getptr(v) : NULL;
-  return def ? upb_dyncast_msgdef(def) : NULL;
-}
-
-const upb_enumdef *upb_symtab_lookupenum(const upb_symtab *s, const char *sym) {
-  upb_value v;
-  upb_def *def = upb_strtable_lookup(&s->symtab, sym, &v) ?
-      upb_value_getptr(v) : NULL;
-  return def ? upb_dyncast_enumdef(def) : NULL;
-}
-
-/* Given a symbol and the base symbol inside which it is defined, find the
- * symbol's definition in t. */
-static upb_def *upb_resolvename(const upb_strtable *t,
-                                const char *base, const char *sym) {
-  if(strlen(sym) == 0) return NULL;
-  if(sym[0] == '.') {
-    /* Symbols starting with '.' are absolute, so we do a single lookup.
-     * Slice to omit the leading '.' */
-    upb_value v;
-    return upb_strtable_lookup(t, sym + 1, &v) ? upb_value_getptr(v) : NULL;
-  } else {
-    /* Remove components from base until we find an entry or run out.
-     * TODO: This branch is totally broken, but currently not used. */
-    (void)base;
-    assert(false);
-    return NULL;
-  }
-}
-
-const upb_def *upb_symtab_resolve(const upb_symtab *s, const char *base,
-                                  const char *sym) {
-  upb_def *ret = upb_resolvename(&s->symtab, base, sym);
-  return ret;
-}
-
-/* Starts a depth-first traversal at "def", recursing into any subdefs
- * (ie. submessage types).  Adds duplicates of existing defs to addtab
- * wherever necessary, so that the resulting symtab will be consistent once
- * addtab is added.
- *
- * More specifically, if any def D is found in the DFS that:
- *
- *   1. can reach a def that is being replaced by something in addtab, AND
- *
- *   2. is not itself being replaced already (ie. this name doesn't already
- *      exist in addtab)
- *
- * ...then a duplicate (new copy) of D will be added to addtab.
- *
- * Returns true if this happened for any def reachable from "def."
- *
- * It is slightly tricky to do this correctly in the presence of cycles.  If we
- * detect that our DFS has hit a cycle, we might not yet know if any SCCs on
- * our stack can reach a def in addtab or not.  Once we figure this out, that
- * answer needs to apply to *all* defs in these SCCs, even if we visited them
- * already.  So a straight up one-pass cycle-detecting DFS won't work.
- *
- * To work around this problem, we traverse each SCC (which we already
- * computed, since these defs are frozen) as a single node.  We first compute
- * whether the SCC as a whole can reach any def in addtab, then we dup (or not)
- * the entire SCC.  This requires breaking the encapsulation of upb_refcounted,
- * since that is where we get the data about what SCC we are in. */
-static bool upb_resolve_dfs(const upb_def *def, upb_strtable *addtab,
-                            const void *new_owner, upb_inttable *seen,
-                            upb_status *s) {
-  upb_value v;
-  bool need_dup;
-  const upb_def *base;
-  const void* memoize_key;
-
-  /* Memoize results of this function for efficiency (since we're traversing a
-   * DAG this is not needed to limit the depth of the search).
-   *
-   * We memoize by SCC instead of by individual def. */
-  memoize_key = def->base.group;
-
-  if (upb_inttable_lookupptr(seen, memoize_key, &v))
-    return upb_value_getbool(v);
-
-  /* Visit submessages for all messages in the SCC. */
-  need_dup = false;
-  base = def;
-  do {
-    upb_value v;
-    const upb_msgdef *m;
-
-    assert(upb_def_isfrozen(def));
-    if (def->type == UPB_DEF_FIELD) continue;
-    if (upb_strtable_lookup(addtab, upb_def_fullname(def), &v)) {
-      need_dup = true;
-    }
-
-    /* For messages, continue the recursion by visiting all subdefs, but only
-     * ones in different SCCs. */
-    m = upb_dyncast_msgdef(def);
-    if (m) {
-      upb_msg_field_iter i;
-      for(upb_msg_field_begin(&i, m);
-          !upb_msg_field_done(&i);
-          upb_msg_field_next(&i)) {
-        upb_fielddef *f = upb_msg_iter_field(&i);
-        const upb_def *subdef;
-
-        if (!upb_fielddef_hassubdef(f)) continue;
-        subdef = upb_fielddef_subdef(f);
-
-        /* Skip subdefs in this SCC. */
-        if (def->base.group == subdef->base.group) continue;
-
-        /* |= to avoid short-circuit; we need its side-effects. */
-        need_dup |= upb_resolve_dfs(subdef, addtab, new_owner, seen, s);
-        if (!upb_ok(s)) return false;
-      }
-    }
-  } while ((def = (upb_def*)def->base.next) != base);
-
-  if (need_dup) {
-    /* Dup all defs in this SCC that don't already have entries in addtab. */
-    def = base;
-    do {
-      const char *name;
-
-      if (def->type == UPB_DEF_FIELD) continue;
-      name = upb_def_fullname(def);
-      if (!upb_strtable_lookup(addtab, name, NULL)) {
-        upb_def *newdef = upb_def_dup(def, new_owner);
-        if (!newdef) goto oom;
-        newdef->came_from_user = false;
-        if (!upb_strtable_insert(addtab, name, upb_value_ptr(newdef)))
-          goto oom;
-      }
-    } while ((def = (upb_def*)def->base.next) != base);
-  }
-
-  upb_inttable_insertptr(seen, memoize_key, upb_value_bool(need_dup));
-  return need_dup;
-
-oom:
-  upb_status_seterrmsg(s, "out of memory");
-  return false;
-}
-
-/* TODO(haberman): we need a lot more testing of error conditions.
- * The came_from_user stuff in particular is not tested. */
-bool upb_symtab_add(upb_symtab *s, upb_def *const*defs, int n, void *ref_donor,
-                    upb_status *status) {
-  int i;
-  upb_strtable_iter iter;
-  upb_def **add_defs = NULL;
-  upb_strtable addtab;
-  upb_inttable seen;
-
-  assert(!upb_symtab_isfrozen(s));
-  if (!upb_strtable_init(&addtab, UPB_CTYPE_PTR)) {
-    upb_status_seterrmsg(status, "out of memory");
-    return false;
-  }
-
-  /* Add new defs to our "add" set. */
-  for (i = 0; i < n; i++) {
-    upb_def *def = defs[i];
-    const char *fullname;
-    upb_fielddef *f;
-
-    if (upb_def_isfrozen(def)) {
-      upb_status_seterrmsg(status, "added defs must be mutable");
-      goto err;
-    }
-    assert(!upb_def_isfrozen(def));
-    fullname = upb_def_fullname(def);
-    if (!fullname) {
-      upb_status_seterrmsg(
-          status, "Anonymous defs cannot be added to a symtab");
-      goto err;
-    }
-
-    f = upb_dyncast_fielddef_mutable(def);
-
-    if (f) {
-      if (!upb_fielddef_containingtypename(f)) {
-        upb_status_seterrmsg(status,
-                             "Standalone fielddefs must have a containing type "
-                             "(extendee) name set");
-        goto err;
-      }
-    } else {
-      if (upb_strtable_lookup(&addtab, fullname, NULL)) {
-        upb_status_seterrf(status, "Conflicting defs named '%s'", fullname);
-        goto err;
-      }
-      /* We need this to back out properly, because if there is a failure we
-       * need to donate the ref back to the caller. */
-      def->came_from_user = true;
-      upb_def_donateref(def, ref_donor, s);
-      if (!upb_strtable_insert(&addtab, fullname, upb_value_ptr(def)))
-        goto oom_err;
-    }
-  }
-
-  /* Add standalone fielddefs (ie. extensions) to the appropriate messages.
-   * If the appropriate message only exists in the existing symtab, duplicate
-   * it so we have a mutable copy we can add the fields to. */
-  for (i = 0; i < n; i++) {
-    upb_def *def = defs[i];
-    upb_fielddef *f = upb_dyncast_fielddef_mutable(def);
-    const char *msgname;
-    upb_value v;
-    upb_msgdef *m;
-
-    if (!f) continue;
-    msgname = upb_fielddef_containingtypename(f);
-    /* We validated this earlier in this function. */
-    assert(msgname);
-
-    /* If the extendee name is absolutely qualified, move past the initial ".".
-     * TODO(haberman): it is not obvious what it would mean if this was not
-     * absolutely qualified. */
-    if (msgname[0] == '.') {
-      msgname++;
-    }
-
-    if (upb_strtable_lookup(&addtab, msgname, &v)) {
-      /* Extendee is in the set of defs the user asked us to add. */
-      m = upb_value_getptr(v);
-    } else {
-      /* Need to find and dup the extendee from the existing symtab. */
-      const upb_msgdef *frozen_m = upb_symtab_lookupmsg(s, msgname);
-      if (!frozen_m) {
-        upb_status_seterrf(status,
-                           "Tried to extend message %s that does not exist "
-                           "in this SymbolTable.",
-                           msgname);
-        goto err;
-      }
-      m = upb_msgdef_dup(frozen_m, s);
-      if (!m) goto oom_err;
-      if (!upb_strtable_insert(&addtab, msgname, upb_value_ptr(m))) {
-        upb_msgdef_unref(m, s);
-        goto oom_err;
-      }
-    }
-
-    if (!upb_msgdef_addfield(m, f, ref_donor, status)) {
-      goto err;
-    }
-  }
-
-  /* Add dups of any existing def that can reach a def with the same name as
-   * anything in our "add" set. */
-  if (!upb_inttable_init(&seen, UPB_CTYPE_BOOL)) goto oom_err;
-  upb_strtable_begin(&iter, &s->symtab);
-  for (; !upb_strtable_done(&iter); upb_strtable_next(&iter)) {
-    upb_def *def = upb_value_getptr(upb_strtable_iter_value(&iter));
-    upb_resolve_dfs(def, &addtab, s, &seen, status);
-    if (!upb_ok(status)) goto err;
-  }
-  upb_inttable_uninit(&seen);
-
-  /* Now using the table, resolve symbolic references for subdefs. */
-  upb_strtable_begin(&iter, &addtab);
-  for (; !upb_strtable_done(&iter); upb_strtable_next(&iter)) {
-    const char *base;
-    upb_def *def = upb_value_getptr(upb_strtable_iter_value(&iter));
-    upb_msgdef *m = upb_dyncast_msgdef_mutable(def);
-    upb_msg_field_iter j;
-
-    if (!m) continue;
-    /* Type names are resolved relative to the message in which they appear. */
-    base = upb_msgdef_fullname(m);
-
-    for(upb_msg_field_begin(&j, m);
-        !upb_msg_field_done(&j);
-        upb_msg_field_next(&j)) {
-      upb_fielddef *f = upb_msg_iter_field(&j);
-      const char *name = upb_fielddef_subdefname(f);
-      if (name && !upb_fielddef_subdef(f)) {
-        /* Try the lookup in the current set of to-be-added defs first. If not
-         * there, try existing defs. */
-        upb_def *subdef = upb_resolvename(&addtab, base, name);
-        if (subdef == NULL) {
-          subdef = upb_resolvename(&s->symtab, base, name);
-        }
-        if (subdef == NULL) {
-          upb_status_seterrf(
-              status, "couldn't resolve name '%s' in message '%s'", name, base);
-          goto err;
-        } else if (!upb_fielddef_setsubdef(f, subdef, status)) {
-          goto err;
-        }
-      }
-    }
-  }
-
-  /* We need an array of the defs in addtab, for passing to upb_def_freeze. */
-  add_defs = malloc(sizeof(void*) * upb_strtable_count(&addtab));
-  if (add_defs == NULL) goto oom_err;
-  upb_strtable_begin(&iter, &addtab);
-  for (n = 0; !upb_strtable_done(&iter); upb_strtable_next(&iter)) {
-    add_defs[n++] = upb_value_getptr(upb_strtable_iter_value(&iter));
-  }
-
-  if (!upb_def_freeze(add_defs, n, status)) goto err;
-
-  /* This must be delayed until all errors have been detected, since error
-   * recovery code uses this table to cleanup defs. */
-  upb_strtable_uninit(&addtab);
-
-  /* TODO(haberman) we don't properly handle errors after this point (like
-   * OOM in upb_strtable_insert() below). */
-  for (i = 0; i < n; i++) {
-    upb_def *def = add_defs[i];
-    const char *name = upb_def_fullname(def);
-    upb_value v;
-    bool success;
-
-    if (upb_strtable_remove(&s->symtab, name, &v)) {
-      const upb_def *def = upb_value_getptr(v);
-      upb_def_unref(def, s);
-    }
-    success = upb_strtable_insert(&s->symtab, name, upb_value_ptr(def));
-    UPB_ASSERT_VAR(success, success == true);
-  }
-  free(add_defs);
-  return true;
-
-oom_err:
-  upb_status_seterrmsg(status, "out of memory");
-err: {
-    /* For defs the user passed in, we need to donate the refs back.  For defs
-     * we dup'd, we need to just unref them. */
-    upb_strtable_begin(&iter, &addtab);
-    for (; !upb_strtable_done(&iter); upb_strtable_next(&iter)) {
-      upb_def *def = upb_value_getptr(upb_strtable_iter_value(&iter));
-      bool came_from_user = def->came_from_user;
-      def->came_from_user = false;
-      if (came_from_user) {
-        upb_def_donateref(def, s, ref_donor);
-      } else {
-        upb_def_unref(def, s);
-      }
-    }
-  }
-  upb_strtable_uninit(&addtab);
-  free(add_defs);
-  assert(!upb_ok(status));
-  return false;
-}
-
-/* Iteration. */
-
-static void advance_to_matching(upb_symtab_iter *iter) {
-  if (iter->type == UPB_DEF_ANY)
-    return;
-
-  while (!upb_strtable_done(&iter->iter) &&
-         iter->type != upb_symtab_iter_def(iter)->type) {
-    upb_strtable_next(&iter->iter);
-  }
-}
-
-void upb_symtab_begin(upb_symtab_iter *iter, const upb_symtab *s,
-                      upb_deftype_t type) {
-  upb_strtable_begin(&iter->iter, &s->symtab);
-  iter->type = type;
-  advance_to_matching(iter);
-}
-
-void upb_symtab_next(upb_symtab_iter *iter) {
-  upb_strtable_next(&iter->iter);
-  advance_to_matching(iter);
-}
-
-bool upb_symtab_done(const upb_symtab_iter *iter) {
-  return upb_strtable_done(&iter->iter);
-}
-
-const upb_def *upb_symtab_iter_def(const upb_symtab_iter *iter) {
-  return upb_value_getptr(upb_strtable_iter_value(&iter->iter));
-}
-/*
-** upb_table Implementation
-**
-** Implementation is heavily inspired by Lua's ltable.c.
-*/
-
-
-#include <stdlib.h>
-#include <string.h>
-
-#define UPB_MAXARRSIZE 16  /* 64k. */
-
-/* From Chromium. */
-#define ARRAY_SIZE(x) \
-    ((sizeof(x)/sizeof(0[x])) / ((size_t)(!(sizeof(x) % sizeof(0[x])))))
-
-static const double MAX_LOAD = 0.85;
-
-/* The minimum utilization of the array part of a mixed hash/array table.  This
- * is a speed/memory-usage tradeoff (though it's not straightforward because of
- * cache effects).  The lower this is, the more memory we'll use. */
-static const double MIN_DENSITY = 0.1;
-
-bool is_pow2(uint64_t v) { return v == 0 || (v & (v - 1)) == 0; }
-
-int log2ceil(uint64_t v) {
-  int ret = 0;
-  bool pow2 = is_pow2(v);
-  while (v >>= 1) ret++;
-  ret = pow2 ? ret : ret + 1;  /* Ceiling. */
-  return UPB_MIN(UPB_MAXARRSIZE, ret);
-}
-
-char *upb_strdup(const char *s) {
-  return upb_strdup2(s, strlen(s));
-}
-
-char *upb_strdup2(const char *s, size_t len) {
-  size_t n;
-  char *p;
-
-  /* Prevent overflow errors. */
-  if (len == SIZE_MAX) return NULL;
-  /* Always null-terminate, even if binary data; but don't rely on the input to
-   * have a null-terminating byte since it may be a raw binary buffer. */
-  n = len + 1;
-  p = malloc(n);
-  if (p) {
-    memcpy(p, s, len);
-    p[len] = 0;
-  }
-  return p;
-}
-
-/* A type to represent the lookup key of either a strtable or an inttable. */
-typedef union {
-  uintptr_t num;
-  struct {
-    const char *str;
-    size_t len;
-  } str;
-} lookupkey_t;
-
-static lookupkey_t strkey2(const char *str, size_t len) {
-  lookupkey_t k;
-  k.str.str = str;
-  k.str.len = len;
-  return k;
-}
-
-static lookupkey_t intkey(uintptr_t key) {
-  lookupkey_t k;
-  k.num = key;
-  return k;
-}
-
-typedef uint32_t hashfunc_t(upb_tabkey key);
-typedef bool eqlfunc_t(upb_tabkey k1, lookupkey_t k2);
-
-/* Base table (shared code) ***************************************************/
-
-/* For when we need to cast away const. */
-static upb_tabent *mutable_entries(upb_table *t) {
-  return (upb_tabent*)t->entries;
-}
-
-static bool isfull(upb_table *t) {
-  return (double)(t->count + 1) / upb_table_size(t) > MAX_LOAD;
-}
-
-static bool init(upb_table *t, upb_ctype_t ctype, uint8_t size_lg2) {
-  size_t bytes;
-
-  t->count = 0;
-  t->ctype = ctype;
-  t->size_lg2 = size_lg2;
-  t->mask = upb_table_size(t) ? upb_table_size(t) - 1 : 0;
-  bytes = upb_table_size(t) * sizeof(upb_tabent);
-  if (bytes > 0) {
-    t->entries = malloc(bytes);
-    if (!t->entries) return false;
-    memset(mutable_entries(t), 0, bytes);
-  } else {
-    t->entries = NULL;
-  }
-  return true;
-}
-
-static void uninit(upb_table *t) { free(mutable_entries(t)); }
-
-static upb_tabent *emptyent(upb_table *t) {
-  upb_tabent *e = mutable_entries(t) + upb_table_size(t);
-  while (1) { if (upb_tabent_isempty(--e)) return e; assert(e > t->entries); }
-}
-
-static upb_tabent *getentry_mutable(upb_table *t, uint32_t hash) {
-  return (upb_tabent*)upb_getentry(t, hash);
-}
-
-static const upb_tabent *findentry(const upb_table *t, lookupkey_t key,
-                                   uint32_t hash, eqlfunc_t *eql) {
-  const upb_tabent *e;
-
-  if (t->size_lg2 == 0) return NULL;
-  e = upb_getentry(t, hash);
-  if (upb_tabent_isempty(e)) return NULL;
-  while (1) {
-    if (eql(e->key, key)) return e;
-    if ((e = e->next) == NULL) return NULL;
-  }
-}
-
-static upb_tabent *findentry_mutable(upb_table *t, lookupkey_t key,
-                                     uint32_t hash, eqlfunc_t *eql) {
-  return (upb_tabent*)findentry(t, key, hash, eql);
-}
-
-static bool lookup(const upb_table *t, lookupkey_t key, upb_value *v,
-                   uint32_t hash, eqlfunc_t *eql) {
-  const upb_tabent *e = findentry(t, key, hash, eql);
-  if (e) {
-    if (v) {
-      _upb_value_setval(v, e->val.val, t->ctype);
-    }
-    return true;
-  } else {
-    return false;
-  }
-}
-
-/* The given key must not already exist in the table. */
-static void insert(upb_table *t, lookupkey_t key, upb_tabkey tabkey,
-                   upb_value val, uint32_t hash,
-                   hashfunc_t *hashfunc, eqlfunc_t *eql) {
-  upb_tabent *mainpos_e;
-  upb_tabent *our_e;
-
-  UPB_UNUSED(eql);
-  UPB_UNUSED(key);
-  assert(findentry(t, key, hash, eql) == NULL);
-  assert(val.ctype == t->ctype);
-
-  t->count++;
-  mainpos_e = getentry_mutable(t, hash);
-  our_e = mainpos_e;
-
-  if (upb_tabent_isempty(mainpos_e)) {
-    /* Our main position is empty; use it. */
-    our_e->next = NULL;
-  } else {
-    /* Collision. */
-    upb_tabent *new_e = emptyent(t);
-    /* Head of collider's chain. */
-    upb_tabent *chain = getentry_mutable(t, hashfunc(mainpos_e->key));
-    if (chain == mainpos_e) {
-      /* Existing ent is in its main posisiton (it has the same hash as us, and
-       * is the head of our chain).  Insert to new ent and append to this chain. */
-      new_e->next = mainpos_e->next;
-      mainpos_e->next = new_e;
-      our_e = new_e;
-    } else {
-      /* Existing ent is not in its main position (it is a node in some other
-       * chain).  This implies that no existing ent in the table has our hash.
-       * Evict it (updating its chain) and use its ent for head of our chain. */
-      *new_e = *mainpos_e;  /* copies next. */
-      while (chain->next != mainpos_e) {
-        chain = (upb_tabent*)chain->next;
-        assert(chain);
-      }
-      chain->next = new_e;
-      our_e = mainpos_e;
-      our_e->next = NULL;
-    }
-  }
-  our_e->key = tabkey;
-  our_e->val.val = val.val;
-  assert(findentry(t, key, hash, eql) == our_e);
-}
-
-static bool rm(upb_table *t, lookupkey_t key, upb_value *val,
-               upb_tabkey *removed, uint32_t hash, eqlfunc_t *eql) {
-  upb_tabent *chain = getentry_mutable(t, hash);
-  if (upb_tabent_isempty(chain)) return false;
-  if (eql(chain->key, key)) {
-    /* Element to remove is at the head of its chain. */
-    t->count--;
-    if (val) {
-      _upb_value_setval(val, chain->val.val, t->ctype);
-    }
-    if (chain->next) {
-      upb_tabent *move = (upb_tabent*)chain->next;
-      *chain = *move;
-      if (removed) *removed = move->key;
-      move->key = 0;  /* Make the slot empty. */
-    } else {
-      if (removed) *removed = chain->key;
-      chain->key = 0;  /* Make the slot empty. */
-    }
-    return true;
-  } else {
-    /* Element to remove is either in a non-head position or not in the
-     * table. */
-    while (chain->next && !eql(chain->next->key, key))
-      chain = (upb_tabent*)chain->next;
-    if (chain->next) {
-      /* Found element to remove. */
-      upb_tabent *rm;
-
-      if (val) {
-        _upb_value_setval(val, chain->next->val.val, t->ctype);
-      }
-      rm = (upb_tabent*)chain->next;
-      if (removed) *removed = rm->key;
-      rm->key = 0;
-      chain->next = rm->next;
-      t->count--;
-      return true;
-    } else {
-      return false;
-    }
-  }
-}
-
-static size_t next(const upb_table *t, size_t i) {
-  do {
-    if (++i >= upb_table_size(t))
-      return SIZE_MAX;
-  } while(upb_tabent_isempty(&t->entries[i]));
-
-  return i;
-}
-
-static size_t begin(const upb_table *t) {
-  return next(t, -1);
-}
-
-
-/* upb_strtable ***************************************************************/
-
-/* A simple "subclass" of upb_table that only adds a hash function for strings. */
-
-static upb_tabkey strcopy(lookupkey_t k2) {
-  char *str = malloc(k2.str.len + sizeof(uint32_t) + 1);
-  if (str == NULL) return 0;
-  memcpy(str, &k2.str.len, sizeof(uint32_t));
-  memcpy(str + sizeof(uint32_t), k2.str.str, k2.str.len + 1);
-  return (uintptr_t)str;
-}
-
-static uint32_t strhash(upb_tabkey key) {
-  uint32_t len;
-  char *str = upb_tabstr(key, &len);
-  return MurmurHash2(str, len, 0);
-}
-
-static bool streql(upb_tabkey k1, lookupkey_t k2) {
-  uint32_t len;
-  char *str = upb_tabstr(k1, &len);
-  return len == k2.str.len && memcmp(str, k2.str.str, len) == 0;
-}
-
-bool upb_strtable_init(upb_strtable *t, upb_ctype_t ctype) {
-  return init(&t->t, ctype, 2);
-}
-
-void upb_strtable_uninit(upb_strtable *t) {
-  size_t i;
-  for (i = 0; i < upb_table_size(&t->t); i++)
-    free((void*)t->t.entries[i].key);
-  uninit(&t->t);
-}
-
-bool upb_strtable_resize(upb_strtable *t, size_t size_lg2) {
-  upb_strtable new_table;
-  upb_strtable_iter i;
-
-  if (!init(&new_table.t, t->t.ctype, size_lg2))
-    return false;
-  upb_strtable_begin(&i, t);
-  for ( ; !upb_strtable_done(&i); upb_strtable_next(&i)) {
-    upb_strtable_insert2(
-        &new_table,
-        upb_strtable_iter_key(&i),
-        upb_strtable_iter_keylength(&i),
-        upb_strtable_iter_value(&i));
-  }
-  upb_strtable_uninit(t);
-  *t = new_table;
-  return true;
-}
-
-bool upb_strtable_insert2(upb_strtable *t, const char *k, size_t len,
-                          upb_value v) {
-  lookupkey_t key;
-  upb_tabkey tabkey;
-  uint32_t hash;
-
-  if (isfull(&t->t)) {
-    /* Need to resize.  New table of double the size, add old elements to it. */
-    if (!upb_strtable_resize(t, t->t.size_lg2 + 1)) {
-      return false;
-    }
-  }
-
-  key = strkey2(k, len);
-  tabkey = strcopy(key);
-  if (tabkey == 0) return false;
-
-  hash = MurmurHash2(key.str.str, key.str.len, 0);
-  insert(&t->t, key, tabkey, v, hash, &strhash, &streql);
-  return true;
-}
-
-bool upb_strtable_lookup2(const upb_strtable *t, const char *key, size_t len,
-                          upb_value *v) {
-  uint32_t hash = MurmurHash2(key, len, 0);
-  return lookup(&t->t, strkey2(key, len), v, hash, &streql);
-}
-
-bool upb_strtable_remove2(upb_strtable *t, const char *key, size_t len,
-                         upb_value *val) {
-  uint32_t hash = MurmurHash2(key, strlen(key), 0);
-  upb_tabkey tabkey;
-  if (rm(&t->t, strkey2(key, len), val, &tabkey, hash, &streql)) {
-    free((void*)tabkey);
-    return true;
-  } else {
-    return false;
-  }
-}
-
-/* Iteration */
-
-static const upb_tabent *str_tabent(const upb_strtable_iter *i) {
-  return &i->t->t.entries[i->index];
-}
-
-void upb_strtable_begin(upb_strtable_iter *i, const upb_strtable *t) {
-  i->t = t;
-  i->index = begin(&t->t);
-}
-
-void upb_strtable_next(upb_strtable_iter *i) {
-  i->index = next(&i->t->t, i->index);
-}
-
-bool upb_strtable_done(const upb_strtable_iter *i) {
-  return i->index >= upb_table_size(&i->t->t) ||
-         upb_tabent_isempty(str_tabent(i));
-}
-
-const char *upb_strtable_iter_key(upb_strtable_iter *i) {
-  assert(!upb_strtable_done(i));
-  return upb_tabstr(str_tabent(i)->key, NULL);
-}
-
-size_t upb_strtable_iter_keylength(upb_strtable_iter *i) {
-  uint32_t len;
-  assert(!upb_strtable_done(i));
-  upb_tabstr(str_tabent(i)->key, &len);
-  return len;
-}
-
-upb_value upb_strtable_iter_value(const upb_strtable_iter *i) {
-  assert(!upb_strtable_done(i));
-  return _upb_value_val(str_tabent(i)->val.val, i->t->t.ctype);
-}
-
-void upb_strtable_iter_setdone(upb_strtable_iter *i) {
-  i->index = SIZE_MAX;
-}
-
-bool upb_strtable_iter_isequal(const upb_strtable_iter *i1,
-                               const upb_strtable_iter *i2) {
-  if (upb_strtable_done(i1) && upb_strtable_done(i2))
-    return true;
-  return i1->t == i2->t && i1->index == i2->index;
-}
-
-
-/* upb_inttable ***************************************************************/
-
-/* For inttables we use a hybrid structure where small keys are kept in an
- * array and large keys are put in the hash table. */
-
-static uint32_t inthash(upb_tabkey key) { return upb_inthash(key); }
-
-static bool inteql(upb_tabkey k1, lookupkey_t k2) {
-  return k1 == k2.num;
-}
-
-static upb_tabval *mutable_array(upb_inttable *t) {
-  return (upb_tabval*)t->array;
-}
-
-static upb_tabval *inttable_val(upb_inttable *t, uintptr_t key) {
-  if (key < t->array_size) {
-    return upb_arrhas(t->array[key]) ? &(mutable_array(t)[key]) : NULL;
-  } else {
-    upb_tabent *e =
-        findentry_mutable(&t->t, intkey(key), upb_inthash(key), &inteql);
-    return e ? &e->val : NULL;
-  }
-}
-
-static const upb_tabval *inttable_val_const(const upb_inttable *t,
-                                            uintptr_t key) {
-  return inttable_val((upb_inttable*)t, key);
-}
-
-size_t upb_inttable_count(const upb_inttable *t) {
-  return t->t.count + t->array_count;
-}
-
-static void check(upb_inttable *t) {
-  UPB_UNUSED(t);
-#if defined(UPB_DEBUG_TABLE) && !defined(NDEBUG)
-  {
-    /* This check is very expensive (makes inserts/deletes O(N)). */
-    size_t count = 0;
-    upb_inttable_iter i;
-    upb_inttable_begin(&i, t);
-    for(; !upb_inttable_done(&i); upb_inttable_next(&i), count++) {
-      assert(upb_inttable_lookup(t, upb_inttable_iter_key(&i), NULL));
-    }
-    assert(count == upb_inttable_count(t));
-  }
-#endif
-}
-
-bool upb_inttable_sizedinit(upb_inttable *t, upb_ctype_t ctype,
-                            size_t asize, int hsize_lg2) {
-  size_t array_bytes;
-
-  if (!init(&t->t, ctype, hsize_lg2)) return false;
-  /* Always make the array part at least 1 long, so that we know key 0
-   * won't be in the hash part, which simplifies things. */
-  t->array_size = UPB_MAX(1, asize);
-  t->array_count = 0;
-  array_bytes = t->array_size * sizeof(upb_value);
-  t->array = malloc(array_bytes);
-  if (!t->array) {
-    uninit(&t->t);
-    return false;
-  }
-  memset(mutable_array(t), 0xff, array_bytes);
-  check(t);
-  return true;
-}
-
-bool upb_inttable_init(upb_inttable *t, upb_ctype_t ctype) {
-  return upb_inttable_sizedinit(t, ctype, 0, 4);
-}
-
-void upb_inttable_uninit(upb_inttable *t) {
-  uninit(&t->t);
-  free(mutable_array(t));
-}
-
-bool upb_inttable_insert(upb_inttable *t, uintptr_t key, upb_value val) {
-  /* XXX: Table can't store value (uint64_t)-1.  Need to somehow statically
-   * guarantee that this is not necessary, or fix the limitation. */
-  upb_tabval tabval;
-  tabval.val = val.val;
-  UPB_UNUSED(tabval);
-  assert(upb_arrhas(tabval));
-
-  if (key < t->array_size) {
-    assert(!upb_arrhas(t->array[key]));
-    t->array_count++;
-    mutable_array(t)[key].val = val.val;
-  } else {
-    if (isfull(&t->t)) {
-      /* Need to resize the hash part, but we re-use the array part. */
-      size_t i;
-      upb_table new_table;
-      if (!init(&new_table, t->t.ctype, t->t.size_lg2 + 1))
-        return false;
-      for (i = begin(&t->t); i < upb_table_size(&t->t); i = next(&t->t, i)) {
-        const upb_tabent *e = &t->t.entries[i];
-        uint32_t hash;
-        upb_value v;
-
-        _upb_value_setval(&v, e->val.val, t->t.ctype);
-        hash = upb_inthash(e->key);
-        insert(&new_table, intkey(e->key), e->key, v, hash, &inthash, &inteql);
-      }
-
-      assert(t->t.count == new_table.count);
-
-      uninit(&t->t);
-      t->t = new_table;
-    }
-    insert(&t->t, intkey(key), key, val, upb_inthash(key), &inthash, &inteql);
-  }
-  check(t);
-  return true;
-}
-
-bool upb_inttable_lookup(const upb_inttable *t, uintptr_t key, upb_value *v) {
-  const upb_tabval *table_v = inttable_val_const(t, key);
-  if (!table_v) return false;
-  if (v) _upb_value_setval(v, table_v->val, t->t.ctype);
-  return true;
-}
-
-bool upb_inttable_replace(upb_inttable *t, uintptr_t key, upb_value val) {
-  upb_tabval *table_v = inttable_val(t, key);
-  if (!table_v) return false;
-  table_v->val = val.val;
-  return true;
-}
-
-bool upb_inttable_remove(upb_inttable *t, uintptr_t key, upb_value *val) {
-  bool success;
-  if (key < t->array_size) {
-    if (upb_arrhas(t->array[key])) {
-      upb_tabval empty = UPB_TABVALUE_EMPTY_INIT;
-      t->array_count--;
-      if (val) {
-        _upb_value_setval(val, t->array[key].val, t->t.ctype);
-      }
-      mutable_array(t)[key] = empty;
-      success = true;
-    } else {
-      success = false;
-    }
-  } else {
-    upb_tabkey removed;
-    uint32_t hash = upb_inthash(key);
-    success = rm(&t->t, intkey(key), val, &removed, hash, &inteql);
-  }
-  check(t);
-  return success;
-}
-
-bool upb_inttable_push(upb_inttable *t, upb_value val) {
-  return upb_inttable_insert(t, upb_inttable_count(t), val);
-}
-
-upb_value upb_inttable_pop(upb_inttable *t) {
-  upb_value val;
-  bool ok = upb_inttable_remove(t, upb_inttable_count(t) - 1, &val);
-  UPB_ASSERT_VAR(ok, ok);
-  return val;
-}
-
-bool upb_inttable_insertptr(upb_inttable *t, const void *key, upb_value val) {
-  return upb_inttable_insert(t, (uintptr_t)key, val);
-}
-
-bool upb_inttable_lookupptr(const upb_inttable *t, const void *key,
-                            upb_value *v) {
-  return upb_inttable_lookup(t, (uintptr_t)key, v);
-}
-
-bool upb_inttable_removeptr(upb_inttable *t, const void *key, upb_value *val) {
-  return upb_inttable_remove(t, (uintptr_t)key, val);
-}
-
-void upb_inttable_compact(upb_inttable *t) {
-  /* Create a power-of-two histogram of the table keys. */
-  int counts[UPB_MAXARRSIZE + 1] = {0};
-  uintptr_t max_key = 0;
-  upb_inttable_iter i;
-  size_t arr_size;
-  int arr_count;
-  upb_inttable new_t;
-
-  upb_inttable_begin(&i, t);
-  for (; !upb_inttable_done(&i); upb_inttable_next(&i)) {
-    uintptr_t key = upb_inttable_iter_key(&i);
-    if (key > max_key) {
-      max_key = key;
-    }
-    counts[log2ceil(key)]++;
-  }
-
-  arr_size = 1;
-  arr_count = upb_inttable_count(t);
-
-  if (upb_inttable_count(t) >= max_key * MIN_DENSITY) {
-    /* We can put 100% of the entries in the array part. */
-    arr_size = max_key + 1;
-  } else {
-    /* Find the largest power of two that satisfies the MIN_DENSITY
-     * definition. */
-    int size_lg2;
-    for (size_lg2 = ARRAY_SIZE(counts) - 1; size_lg2 > 1; size_lg2--) {
-      arr_size = 1 << size_lg2;
-      arr_count -= counts[size_lg2];
-      if (arr_count >= arr_size * MIN_DENSITY) {
-        break;
-      }
-    }
-  }
-
-  /* Array part must always be at least 1 entry large to catch lookups of key
-   * 0.  Key 0 must always be in the array part because "0" in the hash part
-   * denotes an empty entry. */
-  arr_size = UPB_MAX(arr_size, 1);
-
-  {
-    /* Insert all elements into new, perfectly-sized table. */
-    int hash_count = upb_inttable_count(t) - arr_count;
-    int hash_size = hash_count ? (hash_count / MAX_LOAD) + 1 : 0;
-    int hashsize_lg2 = log2ceil(hash_size);
-
-    assert(hash_count >= 0);
-    upb_inttable_sizedinit(&new_t, t->t.ctype, arr_size, hashsize_lg2);
-    upb_inttable_begin(&i, t);
-    for (; !upb_inttable_done(&i); upb_inttable_next(&i)) {
-      uintptr_t k = upb_inttable_iter_key(&i);
-      upb_inttable_insert(&new_t, k, upb_inttable_iter_value(&i));
-    }
-    assert(new_t.array_size == arr_size);
-    assert(new_t.t.size_lg2 == hashsize_lg2);
-  }
-  upb_inttable_uninit(t);
-  *t = new_t;
-}
-
-/* Iteration. */
-
-static const upb_tabent *int_tabent(const upb_inttable_iter *i) {
-  assert(!i->array_part);
-  return &i->t->t.entries[i->index];
-}
-
-static upb_tabval int_arrent(const upb_inttable_iter *i) {
-  assert(i->array_part);
-  return i->t->array[i->index];
-}
-
-void upb_inttable_begin(upb_inttable_iter *i, const upb_inttable *t) {
-  i->t = t;
-  i->index = -1;
-  i->array_part = true;
-  upb_inttable_next(i);
-}
-
-void upb_inttable_next(upb_inttable_iter *iter) {
-  const upb_inttable *t = iter->t;
-  if (iter->array_part) {
-    while (++iter->index < t->array_size) {
-      if (upb_arrhas(int_arrent(iter))) {
-        return;
-      }
-    }
-    iter->array_part = false;
-    iter->index = begin(&t->t);
-  } else {
-    iter->index = next(&t->t, iter->index);
-  }
-}
-
-bool upb_inttable_done(const upb_inttable_iter *i) {
-  if (i->array_part) {
-    return i->index >= i->t->array_size ||
-           !upb_arrhas(int_arrent(i));
-  } else {
-    return i->index >= upb_table_size(&i->t->t) ||
-           upb_tabent_isempty(int_tabent(i));
-  }
-}
-
-uintptr_t upb_inttable_iter_key(const upb_inttable_iter *i) {
-  assert(!upb_inttable_done(i));
-  return i->array_part ? i->index : int_tabent(i)->key;
-}
-
-upb_value upb_inttable_iter_value(const upb_inttable_iter *i) {
-  assert(!upb_inttable_done(i));
-  return _upb_value_val(
-      i->array_part ? i->t->array[i->index].val : int_tabent(i)->val.val,
-      i->t->t.ctype);
-}
-
-void upb_inttable_iter_setdone(upb_inttable_iter *i) {
-  i->index = SIZE_MAX;
-  i->array_part = false;
-}
-
-bool upb_inttable_iter_isequal(const upb_inttable_iter *i1,
-                                          const upb_inttable_iter *i2) {
-  if (upb_inttable_done(i1) && upb_inttable_done(i2))
-    return true;
-  return i1->t == i2->t && i1->index == i2->index &&
-         i1->array_part == i2->array_part;
-}
-
-#ifdef UPB_UNALIGNED_READS_OK
-/* -----------------------------------------------------------------------------
- * MurmurHash2, by Austin Appleby (released as public domain).
- * Reformatted and C99-ified by Joshua Haberman.
- * Note - This code makes a few assumptions about how your machine behaves -
- *   1. We can read a 4-byte value from any address without crashing
- *   2. sizeof(int) == 4 (in upb this limitation is removed by using uint32_t
- * And it has a few limitations -
- *   1. It will not work incrementally.
- *   2. It will not produce the same results on little-endian and big-endian
- *      machines. */
-uint32_t MurmurHash2(const void *key, size_t len, uint32_t seed) {
-  /* 'm' and 'r' are mixing constants generated offline.
-   * They're not really 'magic', they just happen to work well. */
-  const uint32_t m = 0x5bd1e995;
-  const int32_t r = 24;
-
-  /* Initialize the hash to a 'random' value */
-  uint32_t h = seed ^ len;
-
-  /* Mix 4 bytes at a time into the hash */
-  const uint8_t * data = (const uint8_t *)key;
-  while(len >= 4) {
-    uint32_t k = *(uint32_t *)data;
-
-    k *= m;
-    k ^= k >> r;
-    k *= m;
-
-    h *= m;
-    h ^= k;
-
-    data += 4;
-    len -= 4;
-  }
-
-  /* Handle the last few bytes of the input array */
-  switch(len) {
-    case 3: h ^= data[2] << 16;
-    case 2: h ^= data[1] << 8;
-    case 1: h ^= data[0]; h *= m;
-  };
-
-  /* Do a few final mixes of the hash to ensure the last few
-   * bytes are well-incorporated. */
-  h ^= h >> 13;
-  h *= m;
-  h ^= h >> 15;
-
-  return h;
-}
-
-#else /* !UPB_UNALIGNED_READS_OK */
-
-/* -----------------------------------------------------------------------------
- * MurmurHashAligned2, by Austin Appleby
- * Same algorithm as MurmurHash2, but only does aligned reads - should be safer
- * on certain platforms.
- * Performance will be lower than MurmurHash2 */
-
-#define MIX(h,k,m) { k *= m; k ^= k >> r; k *= m; h *= m; h ^= k; }
-
-uint32_t MurmurHash2(const void * key, size_t len, uint32_t seed) {
-  const uint32_t m = 0x5bd1e995;
-  const int32_t r = 24;
-  const uint8_t * data = (const uint8_t *)key;
-  uint32_t h = seed ^ len;
-  uint8_t align = (uintptr_t)data & 3;
-
-  if(align && (len >= 4)) {
-    /* Pre-load the temp registers */
-    uint32_t t = 0, d = 0;
-    int32_t sl;
-    int32_t sr;
-
-    switch(align) {
-      case 1: t |= data[2] << 16;
-      case 2: t |= data[1] << 8;
-      case 3: t |= data[0];
-    }
-
-    t <<= (8 * align);
-
-    data += 4-align;
-    len -= 4-align;
-
-    sl = 8 * (4-align);
-    sr = 8 * align;
-
-    /* Mix */
-
-    while(len >= 4) {
-      uint32_t k;
-
-      d = *(uint32_t *)data;
-      t = (t >> sr) | (d << sl);
-
-      k = t;
-
-      MIX(h,k,m);
-
-      t = d;
-
-      data += 4;
-      len -= 4;
-    }
-
-    /* Handle leftover data in temp registers */
-
-    d = 0;
-
-    if(len >= align) {
-      uint32_t k;
-
-      switch(align) {
-        case 3: d |= data[2] << 16;
-        case 2: d |= data[1] << 8;
-        case 1: d |= data[0];
-      }
-
-      k = (t >> sr) | (d << sl);
-      MIX(h,k,m);
-
-      data += align;
-      len -= align;
-
-      /* ----------
-       * Handle tail bytes */
-
-      switch(len) {
-        case 3: h ^= data[2] << 16;
-        case 2: h ^= data[1] << 8;
-        case 1: h ^= data[0]; h *= m;
-      };
-    } else {
-      switch(len) {
-        case 3: d |= data[2] << 16;
-        case 2: d |= data[1] << 8;
-        case 1: d |= data[0];
-        case 0: h ^= (t >> sr) | (d << sl); h *= m;
-      }
-    }
-
-    h ^= h >> 13;
-    h *= m;
-    h ^= h >> 15;
-
-    return h;
-  } else {
-    while(len >= 4) {
-      uint32_t k = *(uint32_t *)data;
-
-      MIX(h,k,m);
-
-      data += 4;
-      len -= 4;
-    }
-
-    /* ----------
-     * Handle tail bytes */
-
-    switch(len) {
-      case 3: h ^= data[2] << 16;
-      case 2: h ^= data[1] << 8;
-      case 1: h ^= data[0]; h *= m;
-    };
-
-    h ^= h >> 13;
-    h *= m;
-    h ^= h >> 15;
-
-    return h;
-  }
-}
-#undef MIX
-
-#endif /* UPB_UNALIGNED_READS_OK */
-
-#include <errno.h>
-#include <stdarg.h>
-#include <stddef.h>
-#include <stdint.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-
-bool upb_dumptostderr(void *closure, const upb_status* status) {
-  UPB_UNUSED(closure);
-  fprintf(stderr, "%s\n", upb_status_errmsg(status));
-  return false;
-}
-
-/* Guarantee null-termination and provide ellipsis truncation.
- * It may be tempting to "optimize" this by initializing these final
- * four bytes up-front and then being careful never to overwrite them,
- * this is safer and simpler. */
-static void nullz(upb_status *status) {
-  const char *ellipsis = "...";
-  size_t len = strlen(ellipsis);
-  assert(sizeof(status->msg) > len);
-  memcpy(status->msg + sizeof(status->msg) - len, ellipsis, len);
-}
-
-void upb_status_clear(upb_status *status) {
-  if (!status) return;
-  status->ok_ = true;
-  status->code_ = 0;
-  status->msg[0] = '\0';
-}
-
-bool upb_ok(const upb_status *status) { return status->ok_; }
-
-upb_errorspace *upb_status_errspace(const upb_status *status) {
-  return status->error_space_;
-}
-
-int upb_status_errcode(const upb_status *status) { return status->code_; }
-
-const char *upb_status_errmsg(const upb_status *status) { return status->msg; }
-
-void upb_status_seterrmsg(upb_status *status, const char *msg) {
-  if (!status) return;
-  status->ok_ = false;
-  strncpy(status->msg, msg, sizeof(status->msg));
-  nullz(status);
-}
-
-void upb_status_seterrf(upb_status *status, const char *fmt, ...) {
-  va_list args;
-  va_start(args, fmt);
-  upb_status_vseterrf(status, fmt, args);
-  va_end(args);
-}
-
-void upb_status_vseterrf(upb_status *status, const char *fmt, va_list args) {
-  if (!status) return;
-  status->ok_ = false;
-  _upb_vsnprintf(status->msg, sizeof(status->msg), fmt, args);
-  nullz(status);
-}
-
-void upb_status_seterrcode(upb_status *status, upb_errorspace *space,
-                           int code) {
-  if (!status) return;
-  status->ok_ = false;
-  status->error_space_ = space;
-  status->code_ = code;
-  space->set_message(status, code);
-}
-
-void upb_status_copy(upb_status *to, const upb_status *from) {
-  if (!to) return;
-  *to = *from;
-}
-/* This file was generated by upbc (the upb compiler).
- * Do not edit -- your changes will be discarded when the file is
- * regenerated. */
-
-
-static const upb_msgdef msgs[20];
-static const upb_fielddef fields[81];
-static const upb_enumdef enums[4];
-static const upb_tabent strentries[236];
-static const upb_tabent intentries[14];
-static const upb_tabval arrays[232];
-
-#ifdef UPB_DEBUG_REFS
-static upb_inttable reftables[212];
-#endif
-
-static const upb_msgdef msgs[20] = {
-  UPB_MSGDEF_INIT("google.protobuf.DescriptorProto", 27, 6, UPB_INTTABLE_INIT(0, 0, UPB_CTYPE_PTR, 0, NULL, &arrays[0], 8, 7), UPB_STRTABLE_INIT(7, 15, UPB_CTYPE_PTR, 4, &strentries[0]),&reftables[0], &reftables[1]),
-  UPB_MSGDEF_INIT("google.protobuf.DescriptorProto.ExtensionRange", 4, 0, UPB_INTTABLE_INIT(0, 0, UPB_CTYPE_PTR, 0, NULL, &arrays[8], 3, 2), UPB_STRTABLE_INIT(2, 3, UPB_CTYPE_PTR, 2, &strentries[16]),&reftables[2], &reftables[3]),
-  UPB_MSGDEF_INIT("google.protobuf.EnumDescriptorProto", 11, 2, UPB_INTTABLE_INIT(0, 0, UPB_CTYPE_PTR, 0, NULL, &arrays[11], 4, 3), UPB_STRTABLE_INIT(3, 3, UPB_CTYPE_PTR, 2, &strentries[20]),&reftables[4], &reftables[5]),
-  UPB_MSGDEF_INIT("google.protobuf.EnumOptions", 7, 1, UPB_INTTABLE_INIT(1, 1, UPB_CTYPE_PTR, 1, &intentries[0], &arrays[15], 8, 1), UPB_STRTABLE_INIT(2, 3, UPB_CTYPE_PTR, 2, &strentries[24]),&reftables[6], &reftables[7]),
-  UPB_MSGDEF_INIT("google.protobuf.EnumValueDescriptorProto", 8, 1, UPB_INTTABLE_INIT(0, 0, UPB_CTYPE_PTR, 0, NULL, &arrays[23], 4, 3), UPB_STRTABLE_INIT(3, 3, UPB_CTYPE_PTR, 2, &strentries[28]),&reftables[8], &reftables[9]),
-  UPB_MSGDEF_INIT("google.protobuf.EnumValueOptions", 6, 1, UPB_INTTABLE_INIT(1, 1, UPB_CTYPE_PTR, 1, &intentries[2], &arrays[27], 4, 0), UPB_STRTABLE_INIT(1, 3, UPB_CTYPE_PTR, 2, &strentries[32]),&reftables[10], &reftables[11]),
-  UPB_MSGDEF_INIT("google.protobuf.FieldDescriptorProto", 19, 1, UPB_INTTABLE_INIT(0, 0, UPB_CTYPE_PTR, 0, NULL, &arrays[31], 9, 8), UPB_STRTABLE_INIT(8, 15, UPB_CTYPE_PTR, 4, &strentries[36]),&reftables[12], &reftables[13]),
-  UPB_MSGDEF_INIT("google.protobuf.FieldOptions", 14, 1, UPB_INTTABLE_INIT(1, 1, UPB_CTYPE_PTR, 1, &intentries[4], &arrays[40], 32, 6), UPB_STRTABLE_INIT(7, 15, UPB_CTYPE_PTR, 4, &strentries[52]),&reftables[14], &reftables[15]),
-  UPB_MSGDEF_INIT("google.protobuf.FileDescriptorProto", 39, 6, UPB_INTTABLE_INIT(0, 0, UPB_CTYPE_PTR, 0, NULL, &arrays[72], 12, 11), UPB_STRTABLE_INIT(11, 15, UPB_CTYPE_PTR, 4, &strentries[68]),&reftables[16], &reftables[17]),
-  UPB_MSGDEF_INIT("google.protobuf.FileDescriptorSet", 6, 1, UPB_INTTABLE_INIT(0, 0, UPB_CTYPE_PTR, 0, NULL, &arrays[84], 2, 1), UPB_STRTABLE_INIT(1, 3, UPB_CTYPE_PTR, 2, &strentries[84]),&reftables[18], &reftables[19]),
-  UPB_MSGDEF_INIT("google.protobuf.FileOptions", 21, 1, UPB_INTTABLE_INIT(1, 1, UPB_CTYPE_PTR, 1, &intentries[6], &arrays[86], 64, 9), UPB_STRTABLE_INIT(10, 15, UPB_CTYPE_PTR, 4, &strentries[88]),&reftables[20], &reftables[21]),
-  UPB_MSGDEF_INIT("google.protobuf.MessageOptions", 8, 1, UPB_INTTABLE_INIT(1, 1, UPB_CTYPE_PTR, 1, &intentries[8], &arrays[150], 16, 2), UPB_STRTABLE_INIT(3, 3, UPB_CTYPE_PTR, 2, &strentries[104]),&reftables[22], &reftables[23]),
-  UPB_MSGDEF_INIT("google.protobuf.MethodDescriptorProto", 13, 1, UPB_INTTABLE_INIT(0, 0, UPB_CTYPE_PTR, 0, NULL, &arrays[166], 5, 4), UPB_STRTABLE_INIT(4, 7, UPB_CTYPE_PTR, 3, &strentries[108]),&reftables[24], &reftables[25]),
-  UPB_MSGDEF_INIT("google.protobuf.MethodOptions", 6, 1, UPB_INTTABLE_INIT(1, 1, UPB_CTYPE_PTR, 1, &intentries[10], &arrays[171], 4, 0), UPB_STRTABLE_INIT(1, 3, UPB_CTYPE_PTR, 2, &strentries[116]),&reftables[26], &reftables[27]),
-  UPB_MSGDEF_INIT("google.protobuf.ServiceDescriptorProto", 11, 2, UPB_INTTABLE_INIT(0, 0, UPB_CTYPE_PTR, 0, NULL, &arrays[175], 4, 3), UPB_STRTABLE_INIT(3, 3, UPB_CTYPE_PTR, 2, &strentries[120]),&reftables[28], &reftables[29]),
-  UPB_MSGDEF_INIT("google.protobuf.ServiceOptions", 6, 1, UPB_INTTABLE_INIT(1, 1, UPB_CTYPE_PTR, 1, &intentries[12], &arrays[179], 4, 0), UPB_STRTABLE_INIT(1, 3, UPB_CTYPE_PTR, 2, &strentries[124]),&reftables[30], &reftables[31]),
-  UPB_MSGDEF_INIT("google.protobuf.SourceCodeInfo", 6, 1, UPB_INTTABLE_INIT(0, 0, UPB_CTYPE_PTR, 0, NULL, &arrays[183], 2, 1), UPB_STRTABLE_INIT(1, 3, UPB_CTYPE_PTR, 2, &strentries[128]),&reftables[32], &reftables[33]),
-  UPB_MSGDEF_INIT("google.protobuf.SourceCodeInfo.Location", 14, 0, UPB_INTTABLE_INIT(0, 0, UPB_CTYPE_PTR, 0, NULL, &arrays[185], 5, 4), UPB_STRTABLE_INIT(4, 7, UPB_CTYPE_PTR, 3, &strentries[132]),&reftables[34], &reftables[35]),
-  UPB_MSGDEF_INIT("google.protobuf.UninterpretedOption", 18, 1, UPB_INTTABLE_INIT(0, 0, UPB_CTYPE_PTR, 0, NULL, &arrays[190], 9, 7), UPB_STRTABLE_INIT(7, 15, UPB_CTYPE_PTR, 4, &strentries[140]),&reftables[36], &reftables[37]),
-  UPB_MSGDEF_INIT("google.protobuf.UninterpretedOption.NamePart", 6, 0, UPB_INTTABLE_INIT(0, 0, UPB_CTYPE_PTR, 0, NULL, &arrays[199], 3, 2), UPB_STRTABLE_INIT(2, 3, UPB_CTYPE_PTR, 2, &strentries[156]),&reftables[38], &reftables[39]),
-};
-
-static const upb_fielddef fields[81] = {
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_STRING, 0, false, false, false, false, "aggregate_value", 8, &msgs[18], NULL, 15, 6, {0},&reftables[40], &reftables[41]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_BOOL, 0, false, false, false, false, "allow_alias", 2, &msgs[3], NULL, 6, 1, {0},&reftables[42], &reftables[43]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_BOOL, 0, false, false, false, false, "cc_generic_services", 16, &msgs[10], NULL, 17, 6, {0},&reftables[44], &reftables[45]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_ENUM, 0, false, false, false, false, "ctype", 1, &msgs[7], (const upb_def*)(&enums[2]), 6, 1, {0},&reftables[46], &reftables[47]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_STRING, 0, false, false, false, false, "default_value", 7, &msgs[6], NULL, 16, 7, {0},&reftables[48], &reftables[49]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_REPEATED, UPB_TYPE_STRING, 0, false, false, false, false, "dependency", 3, &msgs[8], NULL, 30, 8, {0},&reftables[50], &reftables[51]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_BOOL, 0, false, false, false, false, "deprecated", 3, &msgs[7], NULL, 8, 3, {0},&reftables[52], &reftables[53]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_DOUBLE, 0, false, false, false, false, "double_value", 6, &msgs[18], NULL, 11, 4, {0},&reftables[54], &reftables[55]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_INT32, UPB_INTFMT_VARIABLE, false, false, false, false, "end", 2, &msgs[1], NULL, 3, 1, {0},&reftables[56], &reftables[57]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_REPEATED, UPB_TYPE_MESSAGE, 0, false, false, false, false, "enum_type", 4, &msgs[0], (const upb_def*)(&msgs[2]), 16, 2, {0},&reftables[58], &reftables[59]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_REPEATED, UPB_TYPE_MESSAGE, 0, false, false, false, false, "enum_type", 5, &msgs[8], (const upb_def*)(&msgs[2]), 13, 1, {0},&reftables[60], &reftables[61]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_STRING, 0, false, false, false, false, "experimental_map_key", 9, &msgs[7], NULL, 10, 5, {0},&reftables[62], &reftables[63]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_STRING, 0, false, false, false, false, "extendee", 2, &msgs[6], NULL, 7, 2, {0},&reftables[64], &reftables[65]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_REPEATED, UPB_TYPE_MESSAGE, 0, false, false, false, false, "extension", 7, &msgs[8], (const upb_def*)(&msgs[6]), 19, 3, {0},&reftables[66], &reftables[67]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_REPEATED, UPB_TYPE_MESSAGE, 0, false, false, false, false, "extension", 6, &msgs[0], (const upb_def*)(&msgs[6]), 22, 4, {0},&reftables[68], &reftables[69]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_REPEATED, UPB_TYPE_MESSAGE, 0, false, false, false, false, "extension_range", 5, &msgs[0], (const upb_def*)(&msgs[1]), 19, 3, {0},&reftables[70], &reftables[71]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_REPEATED, UPB_TYPE_MESSAGE, 0, false, false, false, false, "field", 2, &msgs[0], (const upb_def*)(&msgs[6]), 10, 0, {0},&reftables[72], &reftables[73]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_REPEATED, UPB_TYPE_MESSAGE, 0, false, false, false, false, "file", 1, &msgs[9], (const upb_def*)(&msgs[8]), 5, 0, {0},&reftables[74], &reftables[75]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_STRING, 0, false, false, false, false, "go_package", 11, &msgs[10], NULL, 14, 5, {0},&reftables[76], &reftables[77]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_STRING, 0, false, false, false, false, "identifier_value", 3, &msgs[18], NULL, 6, 1, {0},&reftables[78], &reftables[79]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_STRING, 0, false, false, false, false, "input_type", 2, &msgs[12], NULL, 7, 2, {0},&reftables[80], &reftables[81]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_REQUIRED, UPB_TYPE_BOOL, 0, false, false, false, false, "is_extension", 2, &msgs[19], NULL, 5, 1, {0},&reftables[82], &reftables[83]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_BOOL, 0, false, false, false, false, "java_generate_equals_and_hash", 20, &msgs[10], NULL, 20, 9, {0},&reftables[84], &reftables[85]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_BOOL, 0, false, false, false, false, "java_generic_services", 17, &msgs[10], NULL, 18, 7, {0},&reftables[86], &reftables[87]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_BOOL, 0, false, false, false, false, "java_multiple_files", 10, &msgs[10], NULL, 13, 4, {0},&reftables[88], &reftables[89]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_STRING, 0, false, false, false, false, "java_outer_classname", 8, &msgs[10], NULL, 9, 2, {0},&reftables[90], &reftables[91]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_STRING, 0, false, false, false, false, "java_package", 1, &msgs[10], NULL, 6, 1, {0},&reftables[92], &reftables[93]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_ENUM, 0, false, false, false, false, "label", 4, &msgs[6], (const upb_def*)(&enums[0]), 11, 4, {0},&reftables[94], &reftables[95]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_BOOL, 0, false, false, false, false, "lazy", 5, &msgs[7], NULL, 9, 4, {0},&reftables[96], &reftables[97]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_STRING, 0, false, false, false, false, "leading_comments", 3, &msgs[17], NULL, 8, 2, {0},&reftables[98], &reftables[99]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_REPEATED, UPB_TYPE_MESSAGE, 0, false, false, false, false, "location", 1, &msgs[16], (const upb_def*)(&msgs[17]), 5, 0, {0},&reftables[100], &reftables[101]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_BOOL, 0, false, false, false, false, "message_set_wire_format", 1, &msgs[11], NULL, 6, 1, {0},&reftables[102], &reftables[103]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_REPEATED, UPB_TYPE_MESSAGE, 0, false, false, false, false, "message_type", 4, &msgs[8], (const upb_def*)(&msgs[0]), 10, 0, {0},&reftables[104], &reftables[105]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_REPEATED, UPB_TYPE_MESSAGE, 0, false, false, false, false, "method", 2, &msgs[14], (const upb_def*)(&msgs[12]), 6, 0, {0},&reftables[106], &reftables[107]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_STRING, 0, false, false, false, false, "name", 1, &msgs[8], NULL, 22, 6, {0},&reftables[108], &reftables[109]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_STRING, 0, false, false, false, false, "name", 1, &msgs[14], NULL, 8, 2, {0},&reftables[110], &reftables[111]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_REPEATED, UPB_TYPE_MESSAGE, 0, false, false, false, false, "name", 2, &msgs[18], (const upb_def*)(&msgs[19]), 5, 0, {0},&reftables[112], &reftables[113]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_STRING, 0, false, false, false, false, "name", 1, &msgs[4], NULL, 4, 1, {0},&reftables[114], &reftables[115]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_STRING, 0, false, false, false, false, "name", 1, &msgs[0], NULL, 24, 6, {0},&reftables[116], &reftables[117]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_STRING, 0, false, false, false, false, "name", 1, &msgs[12], NULL, 4, 1, {0},&reftables[118], &reftables[119]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_STRING, 0, false, false, false, false, "name", 1, &msgs[2], NULL, 8, 2, {0},&reftables[120], &reftables[121]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_STRING, 0, false, false, false, false, "name", 1, &msgs[6], NULL, 4, 1, {0},&reftables[122], &reftables[123]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_REQUIRED, UPB_TYPE_STRING, 0, false, false, false, false, "name_part", 1, &msgs[19], NULL, 2, 0, {0},&reftables[124], &reftables[125]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_INT64, UPB_INTFMT_VARIABLE, false, false, false, false, "negative_int_value", 5, &msgs[18], NULL, 10, 3, {0},&reftables[126], &reftables[127]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_REPEATED, UPB_TYPE_MESSAGE, 0, false, false, false, false, "nested_type", 3, &msgs[0], (const upb_def*)(&msgs[0]), 13, 1, {0},&reftables[128], &reftables[129]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_BOOL, 0, false, false, false, false, "no_standard_descriptor_accessor", 2, &msgs[11], NULL, 7, 2, {0},&reftables[130], &reftables[131]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_INT32, UPB_INTFMT_VARIABLE, false, false, false, false, "number", 3, &msgs[6], NULL, 10, 3, {0},&reftables[132], &reftables[133]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_INT32, UPB_INTFMT_VARIABLE, false, false, false, false, "number", 2, &msgs[4], NULL, 7, 2, {0},&reftables[134], &reftables[135]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_ENUM, 0, false, false, false, false, "optimize_for", 9, &msgs[10], (const upb_def*)(&enums[3]), 12, 3, {0},&reftables[136], &reftables[137]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_MESSAGE, 0, false, false, false, false, "options", 7, &msgs[0], (const upb_def*)(&msgs[11]), 23, 5, {0},&reftables[138], &reftables[139]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_MESSAGE, 0, false, false, false, false, "options", 3, &msgs[2], (const upb_def*)(&msgs[3]), 7, 1, {0},&reftables[140], &reftables[141]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_MESSAGE, 0, false, false, false, false, "options", 8, &msgs[6], (const upb_def*)(&msgs[7]), 3, 0, {0},&reftables[142], &reftables[143]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_MESSAGE, 0, false, false, false, false, "options", 3, &msgs[4], (const upb_def*)(&msgs[5]), 3, 0, {0},&reftables[144], &reftables[145]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_MESSAGE, 0, false, false, false, false, "options", 8, &msgs[8], (const upb_def*)(&msgs[10]), 20, 4, {0},&reftables[146], &reftables[147]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_MESSAGE, 0, false, false, false, false, "options", 3, &msgs[14], (const upb_def*)(&msgs[15]), 7, 1, {0},&reftables[148], &reftables[149]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_MESSAGE, 0, false, false, false, false, "options", 4, &msgs[12], (const upb_def*)(&msgs[13]), 3, 0, {0},&reftables[150], &reftables[151]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_STRING, 0, false, false, false, false, "output_type", 3, &msgs[12], NULL, 10, 3, {0},&reftables[152], &reftables[153]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_STRING, 0, false, false, false, false, "package", 2, &msgs[8], NULL, 25, 7, {0},&reftables[154], &reftables[155]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_BOOL, 0, false, false, false, false, "packed", 2, &msgs[7], NULL, 7, 2, {0},&reftables[156], &reftables[157]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_REPEATED, UPB_TYPE_INT32, UPB_INTFMT_VARIABLE, false, false, false, true, "path", 1, &msgs[17], NULL, 4, 0, {0},&reftables[158], &reftables[159]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_UINT64, UPB_INTFMT_VARIABLE, false, false, false, false, "positive_int_value", 4, &msgs[18], NULL, 9, 2, {0},&reftables[160], &reftables[161]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_REPEATED, UPB_TYPE_INT32, UPB_INTFMT_VARIABLE, false, false, false, false, "public_dependency", 10, &msgs[8], NULL, 35, 9, {0},&reftables[162], &reftables[163]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_BOOL, 0, false, false, false, false, "py_generic_services", 18, &msgs[10], NULL, 19, 8, {0},&reftables[164], &reftables[165]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_REPEATED, UPB_TYPE_MESSAGE, 0, false, false, false, false, "service", 6, &msgs[8], (const upb_def*)(&msgs[14]), 16, 2, {0},&reftables[166], &reftables[167]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_MESSAGE, 0, false, false, false, false, "source_code_info", 9, &msgs[8], (const upb_def*)(&msgs[16]), 21, 5, {0},&reftables[168], &reftables[169]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_REPEATED, UPB_TYPE_INT32, UPB_INTFMT_VARIABLE, false, false, false, true, "span", 2, &msgs[17], NULL, 7, 1, {0},&reftables[170], &reftables[171]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_INT32, UPB_INTFMT_VARIABLE, false, false, false, false, "start", 1, &msgs[1], NULL, 2, 0, {0},&reftables[172], &reftables[173]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_BYTES, 0, false, false, false, false, "string_value", 7, &msgs[18], NULL, 12, 5, {0},&reftables[174], &reftables[175]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_STRING, 0, false, false, false, false, "trailing_comments", 4, &msgs[17], NULL, 11, 3, {0},&reftables[176], &reftables[177]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_ENUM, 0, false, false, false, false, "type", 5, &msgs[6], (const upb_def*)(&enums[1]), 12, 5, {0},&reftables[178], &reftables[179]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_STRING, 0, false, false, false, false, "type_name", 6, &msgs[6], NULL, 13, 6, {0},&reftables[180], &reftables[181]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_REPEATED, UPB_TYPE_MESSAGE, 0, false, false, false, false, "uninterpreted_option", 999, &msgs[5], (const upb_def*)(&msgs[18]), 5, 0, {0},&reftables[182], &reftables[183]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_REPEATED, UPB_TYPE_MESSAGE, 0, false, false, false, false, "uninterpreted_option", 999, &msgs[15], (const upb_def*)(&msgs[18]), 5, 0, {0},&reftables[184], &reftables[185]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_REPEATED, UPB_TYPE_MESSAGE, 0, false, false, false, false, "uninterpreted_option", 999, &msgs[3], (const upb_def*)(&msgs[18]), 5, 0, {0},&reftables[186], &reftables[187]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_REPEATED, UPB_TYPE_MESSAGE, 0, false, false, false, false, "uninterpreted_option", 999, &msgs[13], (const upb_def*)(&msgs[18]), 5, 0, {0},&reftables[188], &reftables[189]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_REPEATED, UPB_TYPE_MESSAGE, 0, false, false, false, false, "uninterpreted_option", 999, &msgs[10], (const upb_def*)(&msgs[18]), 5, 0, {0},&reftables[190], &reftables[191]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_REPEATED, UPB_TYPE_MESSAGE, 0, false, false, false, false, "uninterpreted_option", 999, &msgs[11], (const upb_def*)(&msgs[18]), 5, 0, {0},&reftables[192], &reftables[193]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_REPEATED, UPB_TYPE_MESSAGE, 0, false, false, false, false, "uninterpreted_option", 999, &msgs[7], (const upb_def*)(&msgs[18]), 5, 0, {0},&reftables[194], &reftables[195]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_REPEATED, UPB_TYPE_MESSAGE, 0, false, false, false, false, "value", 2, &msgs[2], (const upb_def*)(&msgs[4]), 6, 0, {0},&reftables[196], &reftables[197]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_OPTIONAL, UPB_TYPE_BOOL, 0, false, false, false, false, "weak", 10, &msgs[7], NULL, 13, 6, {0},&reftables[198], &reftables[199]),
-  UPB_FIELDDEF_INIT(UPB_LABEL_REPEATED, UPB_TYPE_INT32, UPB_INTFMT_VARIABLE, false, false, false, false, "weak_dependency", 11, &msgs[8], NULL, 38, 10, {0},&reftables[200], &reftables[201]),
-};
-
-static const upb_enumdef enums[4] = {
-  UPB_ENUMDEF_INIT("google.protobuf.FieldDescriptorProto.Label", UPB_STRTABLE_INIT(3, 3, UPB_CTYPE_INT32, 2, &strentries[160]), UPB_INTTABLE_INIT(0, 0, UPB_CTYPE_CSTR, 0, NULL, &arrays[202], 4, 3), 0, &reftables[202], &reftables[203]),
-  UPB_ENUMDEF_INIT("google.protobuf.FieldDescriptorProto.Type", UPB_STRTABLE_INIT(18, 31, UPB_CTYPE_INT32, 5, &strentries[164]), UPB_INTTABLE_INIT(0, 0, UPB_CTYPE_CSTR, 0, NULL, &arrays[206], 19, 18), 0, &reftables[204], &reftables[205]),
-  UPB_ENUMDEF_INIT("google.protobuf.FieldOptions.CType", UPB_STRTABLE_INIT(3, 3, UPB_CTYPE_INT32, 2, &strentries[196]), UPB_INTTABLE_INIT(0, 0, UPB_CTYPE_CSTR, 0, NULL, &arrays[225], 3, 3), 0, &reftables[206], &reftables[207]),
-  UPB_ENUMDEF_INIT("google.protobuf.FileOptions.OptimizeMode", UPB_STRTABLE_INIT(3, 3, UPB_CTYPE_INT32, 2, &strentries[200]), UPB_INTTABLE_INIT(0, 0, UPB_CTYPE_CSTR, 0, NULL, &arrays[228], 4, 3), 0, &reftables[208], &reftables[209]),
-};
-
-static const upb_tabent strentries[236] = {
-  {UPB_TABKEY_STR("\011", "\000", "\000", "\000", "extension"), UPB_TABVALUE_PTR_INIT(&fields[14]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\004", "\000", "\000", "\000", "name"), UPB_TABVALUE_PTR_INIT(&fields[38]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\005", "\000", "\000", "\000", "field"), UPB_TABVALUE_PTR_INIT(&fields[16]), NULL},
-  {UPB_TABKEY_STR("\017", "\000", "\000", "\000", "extension_range"), UPB_TABVALUE_PTR_INIT(&fields[15]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\013", "\000", "\000", "\000", "nested_type"), UPB_TABVALUE_PTR_INIT(&fields[44]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\007", "\000", "\000", "\000", "options"), UPB_TABVALUE_PTR_INIT(&fields[49]), NULL},
-  {UPB_TABKEY_STR("\011", "\000", "\000", "\000", "enum_type"), UPB_TABVALUE_PTR_INIT(&fields[9]), &strentries[14]},
-  {UPB_TABKEY_STR("\005", "\000", "\000", "\000", "start"), UPB_TABVALUE_PTR_INIT(&fields[66]), NULL},
-  {UPB_TABKEY_STR("\003", "\000", "\000", "\000", "end"), UPB_TABVALUE_PTR_INIT(&fields[8]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\005", "\000", "\000", "\000", "value"), UPB_TABVALUE_PTR_INIT(&fields[78]), NULL},
-  {UPB_TABKEY_STR("\007", "\000", "\000", "\000", "options"), UPB_TABVALUE_PTR_INIT(&fields[50]), NULL},
-  {UPB_TABKEY_STR("\004", "\000", "\000", "\000", "name"), UPB_TABVALUE_PTR_INIT(&fields[40]), &strentries[22]},
-  {UPB_TABKEY_STR("\024", "\000", "\000", "\000", "uninterpreted_option"), UPB_TABVALUE_PTR_INIT(&fields[73]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\013", "\000", "\000", "\000", "allow_alias"), UPB_TABVALUE_PTR_INIT(&fields[1]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\006", "\000", "\000", "\000", "number"), UPB_TABVALUE_PTR_INIT(&fields[47]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\007", "\000", "\000", "\000", "options"), UPB_TABVALUE_PTR_INIT(&fields[52]), NULL},
-  {UPB_TABKEY_STR("\004", "\000", "\000", "\000", "name"), UPB_TABVALUE_PTR_INIT(&fields[37]), &strentries[30]},
-  {UPB_TABKEY_STR("\024", "\000", "\000", "\000", "uninterpreted_option"), UPB_TABVALUE_PTR_INIT(&fields[71]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\005", "\000", "\000", "\000", "label"), UPB_TABVALUE_PTR_INIT(&fields[27]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\004", "\000", "\000", "\000", "name"), UPB_TABVALUE_PTR_INIT(&fields[41]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\006", "\000", "\000", "\000", "number"), UPB_TABVALUE_PTR_INIT(&fields[46]), &strentries[49]},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\011", "\000", "\000", "\000", "type_name"), UPB_TABVALUE_PTR_INIT(&fields[70]), NULL},
-  {UPB_TABKEY_STR("\010", "\000", "\000", "\000", "extendee"), UPB_TABVALUE_PTR_INIT(&fields[12]), NULL},
-  {UPB_TABKEY_STR("\004", "\000", "\000", "\000", "type"), UPB_TABVALUE_PTR_INIT(&fields[69]), &strentries[48]},
-  {UPB_TABKEY_STR("\015", "\000", "\000", "\000", "default_value"), UPB_TABVALUE_PTR_INIT(&fields[4]), NULL},
-  {UPB_TABKEY_STR("\007", "\000", "\000", "\000", "options"), UPB_TABVALUE_PTR_INIT(&fields[51]), NULL},
-  {UPB_TABKEY_STR("\024", "\000", "\000", "\000", "experimental_map_key"), UPB_TABVALUE_PTR_INIT(&fields[11]), &strentries[67]},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\004", "\000", "\000", "\000", "weak"), UPB_TABVALUE_PTR_INIT(&fields[79]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\006", "\000", "\000", "\000", "packed"), UPB_TABVALUE_PTR_INIT(&fields[58]), NULL},
-  {UPB_TABKEY_STR("\004", "\000", "\000", "\000", "lazy"), UPB_TABVALUE_PTR_INIT(&fields[28]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\005", "\000", "\000", "\000", "ctype"), UPB_TABVALUE_PTR_INIT(&fields[3]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\012", "\000", "\000", "\000", "deprecated"), UPB_TABVALUE_PTR_INIT(&fields[6]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\024", "\000", "\000", "\000", "uninterpreted_option"), UPB_TABVALUE_PTR_INIT(&fields[77]), NULL},
-  {UPB_TABKEY_STR("\011", "\000", "\000", "\000", "extension"), UPB_TABVALUE_PTR_INIT(&fields[13]), NULL},
-  {UPB_TABKEY_STR("\017", "\000", "\000", "\000", "weak_dependency"), UPB_TABVALUE_PTR_INIT(&fields[80]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\004", "\000", "\000", "\000", "name"), UPB_TABVALUE_PTR_INIT(&fields[34]), NULL},
-  {UPB_TABKEY_STR("\007", "\000", "\000", "\000", "service"), UPB_TABVALUE_PTR_INIT(&fields[63]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\020", "\000", "\000", "\000", "source_code_info"), UPB_TABVALUE_PTR_INIT(&fields[64]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\012", "\000", "\000", "\000", "dependency"), UPB_TABVALUE_PTR_INIT(&fields[5]), NULL},
-  {UPB_TABKEY_STR("\014", "\000", "\000", "\000", "message_type"), UPB_TABVALUE_PTR_INIT(&fields[32]), NULL},
-  {UPB_TABKEY_STR("\007", "\000", "\000", "\000", "package"), UPB_TABVALUE_PTR_INIT(&fields[57]), NULL},
-  {UPB_TABKEY_STR("\007", "\000", "\000", "\000", "options"), UPB_TABVALUE_PTR_INIT(&fields[53]), &strentries[82]},
-  {UPB_TABKEY_STR("\011", "\000", "\000", "\000", "enum_type"), UPB_TABVALUE_PTR_INIT(&fields[10]), NULL},
-  {UPB_TABKEY_STR("\021", "\000", "\000", "\000", "public_dependency"), UPB_TABVALUE_PTR_INIT(&fields[61]), &strentries[81]},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\004", "\000", "\000", "\000", "file"), UPB_TABVALUE_PTR_INIT(&fields[17]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\024", "\000", "\000", "\000", "uninterpreted_option"), UPB_TABVALUE_PTR_INIT(&fields[75]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\023", "\000", "\000", "\000", "cc_generic_services"), UPB_TABVALUE_PTR_INIT(&fields[2]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\023", "\000", "\000", "\000", "java_multiple_files"), UPB_TABVALUE_PTR_INIT(&fields[24]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\025", "\000", "\000", "\000", "java_generic_services"), UPB_TABVALUE_PTR_INIT(&fields[23]), &strentries[102]},
-  {UPB_TABKEY_STR("\035", "\000", "\000", "\000", "java_generate_equals_and_hash"), UPB_TABVALUE_PTR_INIT(&fields[22]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\012", "\000", "\000", "\000", "go_package"), UPB_TABVALUE_PTR_INIT(&fields[18]), NULL},
-  {UPB_TABKEY_STR("\014", "\000", "\000", "\000", "java_package"), UPB_TABVALUE_PTR_INIT(&fields[26]), NULL},
-  {UPB_TABKEY_STR("\014", "\000", "\000", "\000", "optimize_for"), UPB_TABVALUE_PTR_INIT(&fields[48]), NULL},
-  {UPB_TABKEY_STR("\023", "\000", "\000", "\000", "py_generic_services"), UPB_TABVALUE_PTR_INIT(&fields[62]), NULL},
-  {UPB_TABKEY_STR("\024", "\000", "\000", "\000", "java_outer_classname"), UPB_TABVALUE_PTR_INIT(&fields[25]), NULL},
-  {UPB_TABKEY_STR("\027", "\000", "\000", "\000", "message_set_wire_format"), UPB_TABVALUE_PTR_INIT(&fields[31]), &strentries[106]},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\024", "\000", "\000", "\000", "uninterpreted_option"), UPB_TABVALUE_PTR_INIT(&fields[76]), NULL},
-  {UPB_TABKEY_STR("\037", "\000", "\000", "\000", "no_standard_descriptor_accessor"), UPB_TABVALUE_PTR_INIT(&fields[45]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\004", "\000", "\000", "\000", "name"), UPB_TABVALUE_PTR_INIT(&fields[39]), NULL},
-  {UPB_TABKEY_STR("\012", "\000", "\000", "\000", "input_type"), UPB_TABVALUE_PTR_INIT(&fields[20]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\013", "\000", "\000", "\000", "output_type"), UPB_TABVALUE_PTR_INIT(&fields[56]), NULL},
-  {UPB_TABKEY_STR("\007", "\000", "\000", "\000", "options"), UPB_TABVALUE_PTR_INIT(&fields[55]), NULL},
-  {UPB_TABKEY_STR("\024", "\000", "\000", "\000", "uninterpreted_option"), UPB_TABVALUE_PTR_INIT(&fields[74]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\007", "\000", "\000", "\000", "options"), UPB_TABVALUE_PTR_INIT(&fields[54]), &strentries[122]},
-  {UPB_TABKEY_STR("\006", "\000", "\000", "\000", "method"), UPB_TABVALUE_PTR_INIT(&fields[33]), NULL},
-  {UPB_TABKEY_STR("\004", "\000", "\000", "\000", "name"), UPB_TABVALUE_PTR_INIT(&fields[35]), &strentries[121]},
-  {UPB_TABKEY_STR("\024", "\000", "\000", "\000", "uninterpreted_option"), UPB_TABVALUE_PTR_INIT(&fields[72]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\010", "\000", "\000", "\000", "location"), UPB_TABVALUE_PTR_INIT(&fields[30]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\004", "\000", "\000", "\000", "span"), UPB_TABVALUE_PTR_INIT(&fields[65]), &strentries[139]},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\021", "\000", "\000", "\000", "trailing_comments"), UPB_TABVALUE_PTR_INIT(&fields[68]), NULL},
-  {UPB_TABKEY_STR("\020", "\000", "\000", "\000", "leading_comments"), UPB_TABVALUE_PTR_INIT(&fields[29]), &strentries[137]},
-  {UPB_TABKEY_STR("\004", "\000", "\000", "\000", "path"), UPB_TABVALUE_PTR_INIT(&fields[59]), NULL},
-  {UPB_TABKEY_STR("\014", "\000", "\000", "\000", "double_value"), UPB_TABVALUE_PTR_INIT(&fields[7]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\004", "\000", "\000", "\000", "name"), UPB_TABVALUE_PTR_INIT(&fields[36]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\022", "\000", "\000", "\000", "negative_int_value"), UPB_TABVALUE_PTR_INIT(&fields[43]), NULL},
-  {UPB_TABKEY_STR("\017", "\000", "\000", "\000", "aggregate_value"), UPB_TABVALUE_PTR_INIT(&fields[0]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\022", "\000", "\000", "\000", "positive_int_value"), UPB_TABVALUE_PTR_INIT(&fields[60]), NULL},
-  {UPB_TABKEY_STR("\020", "\000", "\000", "\000", "identifier_value"), UPB_TABVALUE_PTR_INIT(&fields[19]), NULL},
-  {UPB_TABKEY_STR("\014", "\000", "\000", "\000", "string_value"), UPB_TABVALUE_PTR_INIT(&fields[67]), &strentries[154]},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\014", "\000", "\000", "\000", "is_extension"), UPB_TABVALUE_PTR_INIT(&fields[21]), NULL},
-  {UPB_TABKEY_STR("\011", "\000", "\000", "\000", "name_part"), UPB_TABVALUE_PTR_INIT(&fields[42]), NULL},
-  {UPB_TABKEY_STR("\016", "\000", "\000", "\000", "LABEL_REQUIRED"), UPB_TABVALUE_INT_INIT(2), &strentries[162]},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\016", "\000", "\000", "\000", "LABEL_REPEATED"), UPB_TABVALUE_INT_INIT(3), NULL},
-  {UPB_TABKEY_STR("\016", "\000", "\000", "\000", "LABEL_OPTIONAL"), UPB_TABVALUE_INT_INIT(1), NULL},
-  {UPB_TABKEY_STR("\014", "\000", "\000", "\000", "TYPE_FIXED64"), UPB_TABVALUE_INT_INIT(6), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\013", "\000", "\000", "\000", "TYPE_STRING"), UPB_TABVALUE_INT_INIT(9), NULL},
-  {UPB_TABKEY_STR("\012", "\000", "\000", "\000", "TYPE_FLOAT"), UPB_TABVALUE_INT_INIT(2), &strentries[193]},
-  {UPB_TABKEY_STR("\013", "\000", "\000", "\000", "TYPE_DOUBLE"), UPB_TABVALUE_INT_INIT(1), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\012", "\000", "\000", "\000", "TYPE_INT32"), UPB_TABVALUE_INT_INIT(5), NULL},
-  {UPB_TABKEY_STR("\015", "\000", "\000", "\000", "TYPE_SFIXED32"), UPB_TABVALUE_INT_INIT(15), NULL},
-  {UPB_TABKEY_STR("\014", "\000", "\000", "\000", "TYPE_FIXED32"), UPB_TABVALUE_INT_INIT(7), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\014", "\000", "\000", "\000", "TYPE_MESSAGE"), UPB_TABVALUE_INT_INIT(11), &strentries[194]},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\012", "\000", "\000", "\000", "TYPE_INT64"), UPB_TABVALUE_INT_INIT(3), &strentries[191]},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\011", "\000", "\000", "\000", "TYPE_ENUM"), UPB_TABVALUE_INT_INIT(14), NULL},
-  {UPB_TABKEY_STR("\013", "\000", "\000", "\000", "TYPE_UINT32"), UPB_TABVALUE_INT_INIT(13), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\013", "\000", "\000", "\000", "TYPE_UINT64"), UPB_TABVALUE_INT_INIT(4), &strentries[190]},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\015", "\000", "\000", "\000", "TYPE_SFIXED64"), UPB_TABVALUE_INT_INIT(16), NULL},
-  {UPB_TABKEY_STR("\012", "\000", "\000", "\000", "TYPE_BYTES"), UPB_TABVALUE_INT_INIT(12), NULL},
-  {UPB_TABKEY_STR("\013", "\000", "\000", "\000", "TYPE_SINT64"), UPB_TABVALUE_INT_INIT(18), NULL},
-  {UPB_TABKEY_STR("\011", "\000", "\000", "\000", "TYPE_BOOL"), UPB_TABVALUE_INT_INIT(8), NULL},
-  {UPB_TABKEY_STR("\012", "\000", "\000", "\000", "TYPE_GROUP"), UPB_TABVALUE_INT_INIT(10), NULL},
-  {UPB_TABKEY_STR("\013", "\000", "\000", "\000", "TYPE_SINT32"), UPB_TABVALUE_INT_INIT(17), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\004", "\000", "\000", "\000", "CORD"), UPB_TABVALUE_INT_INIT(1), NULL},
-  {UPB_TABKEY_STR("\006", "\000", "\000", "\000", "STRING"), UPB_TABVALUE_INT_INIT(0), &strentries[197]},
-  {UPB_TABKEY_STR("\014", "\000", "\000", "\000", "STRING_PIECE"), UPB_TABVALUE_INT_INIT(2), NULL},
-  {UPB_TABKEY_STR("\011", "\000", "\000", "\000", "CODE_SIZE"), UPB_TABVALUE_INT_INIT(2), NULL},
-  {UPB_TABKEY_STR("\005", "\000", "\000", "\000", "SPEED"), UPB_TABVALUE_INT_INIT(1), &strentries[203]},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\014", "\000", "\000", "\000", "LITE_RUNTIME"), UPB_TABVALUE_INT_INIT(3), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\047", "\000", "\000", "\000", "google.protobuf.SourceCodeInfo.Location"), UPB_TABVALUE_PTR_INIT(&msgs[17]), NULL},
-  {UPB_TABKEY_STR("\043", "\000", "\000", "\000", "google.protobuf.UninterpretedOption"), UPB_TABVALUE_PTR_INIT(&msgs[18]), NULL},
-  {UPB_TABKEY_STR("\043", "\000", "\000", "\000", "google.protobuf.FileDescriptorProto"), UPB_TABVALUE_PTR_INIT(&msgs[8]), NULL},
-  {UPB_TABKEY_STR("\045", "\000", "\000", "\000", "google.protobuf.MethodDescriptorProto"), UPB_TABVALUE_PTR_INIT(&msgs[12]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\040", "\000", "\000", "\000", "google.protobuf.EnumValueOptions"), UPB_TABVALUE_PTR_INIT(&msgs[5]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\037", "\000", "\000", "\000", "google.protobuf.DescriptorProto"), UPB_TABVALUE_PTR_INIT(&msgs[0]), &strentries[228]},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\036", "\000", "\000", "\000", "google.protobuf.SourceCodeInfo"), UPB_TABVALUE_PTR_INIT(&msgs[16]), NULL},
-  {UPB_TABKEY_STR("\051", "\000", "\000", "\000", "google.protobuf.FieldDescriptorProto.Type"), UPB_TABVALUE_PTR_INIT(&enums[1]), NULL},
-  {UPB_TABKEY_STR("\056", "\000", "\000", "\000", "google.protobuf.DescriptorProto.ExtensionRange"), UPB_TABVALUE_PTR_INIT(&msgs[1]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_STR("\050", "\000", "\000", "\000", "google.protobuf.EnumValueDescriptorProto"), UPB_TABVALUE_PTR_INIT(&msgs[4]), NULL},
-  {UPB_TABKEY_STR("\034", "\000", "\000", "\000", "google.protobuf.FieldOptions"), UPB_TABVALUE_PTR_INIT(&msgs[7]), NULL},
-  {UPB_TABKEY_STR("\033", "\000", "\000", "\000", "google.protobuf.FileOptions"), UPB_TABVALUE_PTR_INIT(&msgs[10]), NULL},
-  {UPB_TABKEY_STR("\043", "\000", "\000", "\000", "google.protobuf.EnumDescriptorProto"), UPB_TABVALUE_PTR_INIT(&msgs[2]), &strentries[233]},
-  {UPB_TABKEY_STR("\052", "\000", "\000", "\000", "google.protobuf.FieldDescriptorProto.Label"), UPB_TABVALUE_PTR_INIT(&enums[0]), NULL},
-  {UPB_TABKEY_STR("\046", "\000", "\000", "\000", "google.protobuf.ServiceDescriptorProto"), UPB_TABVALUE_PTR_INIT(&msgs[14]), NULL},
-  {UPB_TABKEY_STR("\042", "\000", "\000", "\000", "google.protobuf.FieldOptions.CType"), UPB_TABVALUE_PTR_INIT(&enums[2]), &strentries[229]},
-  {UPB_TABKEY_STR("\041", "\000", "\000", "\000", "google.protobuf.FileDescriptorSet"), UPB_TABVALUE_PTR_INIT(&msgs[9]), &strentries[235]},
-  {UPB_TABKEY_STR("\033", "\000", "\000", "\000", "google.protobuf.EnumOptions"), UPB_TABVALUE_PTR_INIT(&msgs[3]), NULL},
-  {UPB_TABKEY_STR("\044", "\000", "\000", "\000", "google.protobuf.FieldDescriptorProto"), UPB_TABVALUE_PTR_INIT(&msgs[6]), NULL},
-  {UPB_TABKEY_STR("\050", "\000", "\000", "\000", "google.protobuf.FileOptions.OptimizeMode"), UPB_TABVALUE_PTR_INIT(&enums[3]), &strentries[221]},
-  {UPB_TABKEY_STR("\036", "\000", "\000", "\000", "google.protobuf.ServiceOptions"), UPB_TABVALUE_PTR_INIT(&msgs[15]), NULL},
-  {UPB_TABKEY_STR("\036", "\000", "\000", "\000", "google.protobuf.MessageOptions"), UPB_TABVALUE_PTR_INIT(&msgs[11]), NULL},
-  {UPB_TABKEY_STR("\035", "\000", "\000", "\000", "google.protobuf.MethodOptions"), UPB_TABVALUE_PTR_INIT(&msgs[13]), &strentries[226]},
-  {UPB_TABKEY_STR("\054", "\000", "\000", "\000", "google.protobuf.UninterpretedOption.NamePart"), UPB_TABVALUE_PTR_INIT(&msgs[19]), NULL},
-};
-
-static const upb_tabent intentries[14] = {
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NUM(999), UPB_TABVALUE_PTR_INIT(&fields[73]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NUM(999), UPB_TABVALUE_PTR_INIT(&fields[71]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NUM(999), UPB_TABVALUE_PTR_INIT(&fields[77]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NUM(999), UPB_TABVALUE_PTR_INIT(&fields[75]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NUM(999), UPB_TABVALUE_PTR_INIT(&fields[76]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NUM(999), UPB_TABVALUE_PTR_INIT(&fields[74]), NULL},
-  {UPB_TABKEY_NONE, UPB_TABVALUE_EMPTY_INIT, NULL},
-  {UPB_TABKEY_NUM(999), UPB_TABVALUE_PTR_INIT(&fields[72]), NULL},
-};
-
-static const upb_tabval arrays[232] = {
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_PTR_INIT(&fields[38]),
-  UPB_TABVALUE_PTR_INIT(&fields[16]),
-  UPB_TABVALUE_PTR_INIT(&fields[44]),
-  UPB_TABVALUE_PTR_INIT(&fields[9]),
-  UPB_TABVALUE_PTR_INIT(&fields[15]),
-  UPB_TABVALUE_PTR_INIT(&fields[14]),
-  UPB_TABVALUE_PTR_INIT(&fields[49]),
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_PTR_INIT(&fields[66]),
-  UPB_TABVALUE_PTR_INIT(&fields[8]),
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_PTR_INIT(&fields[40]),
-  UPB_TABVALUE_PTR_INIT(&fields[78]),
-  UPB_TABVALUE_PTR_INIT(&fields[50]),
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_PTR_INIT(&fields[1]),
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_PTR_INIT(&fields[37]),
-  UPB_TABVALUE_PTR_INIT(&fields[47]),
-  UPB_TABVALUE_PTR_INIT(&fields[52]),
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_PTR_INIT(&fields[41]),
-  UPB_TABVALUE_PTR_INIT(&fields[12]),
-  UPB_TABVALUE_PTR_INIT(&fields[46]),
-  UPB_TABVALUE_PTR_INIT(&fields[27]),
-  UPB_TABVALUE_PTR_INIT(&fields[69]),
-  UPB_TABVALUE_PTR_INIT(&fields[70]),
-  UPB_TABVALUE_PTR_INIT(&fields[4]),
-  UPB_TABVALUE_PTR_INIT(&fields[51]),
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_PTR_INIT(&fields[3]),
-  UPB_TABVALUE_PTR_INIT(&fields[58]),
-  UPB_TABVALUE_PTR_INIT(&fields[6]),
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_PTR_INIT(&fields[28]),
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_PTR_INIT(&fields[11]),
-  UPB_TABVALUE_PTR_INIT(&fields[79]),
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_PTR_INIT(&fields[34]),
-  UPB_TABVALUE_PTR_INIT(&fields[57]),
-  UPB_TABVALUE_PTR_INIT(&fields[5]),
-  UPB_TABVALUE_PTR_INIT(&fields[32]),
-  UPB_TABVALUE_PTR_INIT(&fields[10]),
-  UPB_TABVALUE_PTR_INIT(&fields[63]),
-  UPB_TABVALUE_PTR_INIT(&fields[13]),
-  UPB_TABVALUE_PTR_INIT(&fields[53]),
-  UPB_TABVALUE_PTR_INIT(&fields[64]),
-  UPB_TABVALUE_PTR_INIT(&fields[61]),
-  UPB_TABVALUE_PTR_INIT(&fields[80]),
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_PTR_INIT(&fields[17]),
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_PTR_INIT(&fields[26]),
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_PTR_INIT(&fields[25]),
-  UPB_TABVALUE_PTR_INIT(&fields[48]),
-  UPB_TABVALUE_PTR_INIT(&fields[24]),
-  UPB_TABVALUE_PTR_INIT(&fields[18]),
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_PTR_INIT(&fields[2]),
-  UPB_TABVALUE_PTR_INIT(&fields[23]),
-  UPB_TABVALUE_PTR_INIT(&fields[62]),
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_PTR_INIT(&fields[22]),
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_PTR_INIT(&fields[31]),
-  UPB_TABVALUE_PTR_INIT(&fields[45]),
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_PTR_INIT(&fields[39]),
-  UPB_TABVALUE_PTR_INIT(&fields[20]),
-  UPB_TABVALUE_PTR_INIT(&fields[56]),
-  UPB_TABVALUE_PTR_INIT(&fields[55]),
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_PTR_INIT(&fields[35]),
-  UPB_TABVALUE_PTR_INIT(&fields[33]),
-  UPB_TABVALUE_PTR_INIT(&fields[54]),
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_PTR_INIT(&fields[30]),
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_PTR_INIT(&fields[59]),
-  UPB_TABVALUE_PTR_INIT(&fields[65]),
-  UPB_TABVALUE_PTR_INIT(&fields[29]),
-  UPB_TABVALUE_PTR_INIT(&fields[68]),
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_PTR_INIT(&fields[36]),
-  UPB_TABVALUE_PTR_INIT(&fields[19]),
-  UPB_TABVALUE_PTR_INIT(&fields[60]),
-  UPB_TABVALUE_PTR_INIT(&fields[43]),
-  UPB_TABVALUE_PTR_INIT(&fields[7]),
-  UPB_TABVALUE_PTR_INIT(&fields[67]),
-  UPB_TABVALUE_PTR_INIT(&fields[0]),
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_PTR_INIT(&fields[42]),
-  UPB_TABVALUE_PTR_INIT(&fields[21]),
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_PTR_INIT("LABEL_OPTIONAL"),
-  UPB_TABVALUE_PTR_INIT("LABEL_REQUIRED"),
-  UPB_TABVALUE_PTR_INIT("LABEL_REPEATED"),
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_PTR_INIT("TYPE_DOUBLE"),
-  UPB_TABVALUE_PTR_INIT("TYPE_FLOAT"),
-  UPB_TABVALUE_PTR_INIT("TYPE_INT64"),
-  UPB_TABVALUE_PTR_INIT("TYPE_UINT64"),
-  UPB_TABVALUE_PTR_INIT("TYPE_INT32"),
-  UPB_TABVALUE_PTR_INIT("TYPE_FIXED64"),
-  UPB_TABVALUE_PTR_INIT("TYPE_FIXED32"),
-  UPB_TABVALUE_PTR_INIT("TYPE_BOOL"),
-  UPB_TABVALUE_PTR_INIT("TYPE_STRING"),
-  UPB_TABVALUE_PTR_INIT("TYPE_GROUP"),
-  UPB_TABVALUE_PTR_INIT("TYPE_MESSAGE"),
-  UPB_TABVALUE_PTR_INIT("TYPE_BYTES"),
-  UPB_TABVALUE_PTR_INIT("TYPE_UINT32"),
-  UPB_TABVALUE_PTR_INIT("TYPE_ENUM"),
-  UPB_TABVALUE_PTR_INIT("TYPE_SFIXED32"),
-  UPB_TABVALUE_PTR_INIT("TYPE_SFIXED64"),
-  UPB_TABVALUE_PTR_INIT("TYPE_SINT32"),
-  UPB_TABVALUE_PTR_INIT("TYPE_SINT64"),
-  UPB_TABVALUE_PTR_INIT("STRING"),
-  UPB_TABVALUE_PTR_INIT("CORD"),
-  UPB_TABVALUE_PTR_INIT("STRING_PIECE"),
-  UPB_TABVALUE_EMPTY_INIT,
-  UPB_TABVALUE_PTR_INIT("SPEED"),
-  UPB_TABVALUE_PTR_INIT("CODE_SIZE"),
-  UPB_TABVALUE_PTR_INIT("LITE_RUNTIME"),
-};
-
-static const upb_symtab symtab = UPB_SYMTAB_INIT(UPB_STRTABLE_INIT(24, 31, UPB_CTYPE_PTR, 5, &strentries[204]), &reftables[210], &reftables[211]);
-
-const upb_symtab *upbdefs_google_protobuf_descriptor(const void *owner) {
-  upb_symtab_ref(&symtab, owner);
-  return &symtab;
-}
-
-#ifdef UPB_DEBUG_REFS
-static upb_inttable reftables[212] = {
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-  UPB_EMPTY_INTTABLE_INIT(UPB_CTYPE_PTR),
-};
-#endif
-
-/*
-** XXX: The routines in this file that consume a string do not currently
-** support having the string span buffers.  In the future, as upb_sink and
-** its buffering/sharing functionality evolve there should be an easy and
-** idiomatic way of correctly handling this case.  For now, we accept this
-** limitation since we currently only parse descriptors from single strings.
-*/
-
-
-#include <errno.h>
-#include <stdlib.h>
-#include <string.h>
-
-/* upb_deflist is an internal-only dynamic array for storing a growing list of
- * upb_defs. */
-typedef struct {
-  upb_def **defs;
-  size_t len;
-  size_t size;
-  bool owned;
-} upb_deflist;
-
-/* We keep a stack of all the messages scopes we are currently in, as well as
- * the top-level file scope.  This is necessary to correctly qualify the
- * definitions that are contained inside.  "name" tracks the name of the
- * message or package (a bare name -- not qualified by any enclosing scopes). */
-typedef struct {
-  char *name;
-  /* Index of the first def that is under this scope.  For msgdefs, the
-   * msgdef itself is at start-1. */
-  int start;
-} upb_descreader_frame;
-
-/* The maximum number of nested declarations that are allowed, ie.
- * message Foo {
- *   message Bar {
- *     message Baz {
- *     }
- *   }
- * }
- *
- * This is a resource limit that affects how big our runtime stack can grow.
- * TODO: make this a runtime-settable property of the Reader instance. */
-#define UPB_MAX_MESSAGE_NESTING 64
-
-struct upb_descreader {
-  upb_sink sink;
-  upb_deflist defs;
-  upb_descreader_frame stack[UPB_MAX_MESSAGE_NESTING];
-  int stack_len;
-
-  uint32_t number;
-  char *name;
-  bool saw_number;
-  bool saw_name;
-
-  char *default_string;
-
-  upb_fielddef *f;
-};
-
-static char *upb_strndup(const char *buf, size_t n) {
-  char *ret = malloc(n + 1);
-  if (!ret) return NULL;
-  memcpy(ret, buf, n);
-  ret[n] = '\0';
-  return ret;
-}
-
-/* Returns a newly allocated string that joins input strings together, for
- * example:
- *   join("Foo.Bar", "Baz") -> "Foo.Bar.Baz"
- *   join("", "Baz") -> "Baz"
- * Caller owns a ref on the returned string. */
-static char *upb_join(const char *base, const char *name) {
-  if (!base || strlen(base) == 0) {
-    return upb_strdup(name);
-  } else {
-    char *ret = malloc(strlen(base) + strlen(name) + 2);
-    ret[0] = '\0';
-    strcat(ret, base);
-    strcat(ret, ".");
-    strcat(ret, name);
-    return ret;
-  }
-}
-
-
-/* upb_deflist ****************************************************************/
-
-void upb_deflist_init(upb_deflist *l) {
-  l->size = 0;
-  l->defs = NULL;
-  l->len = 0;
-  l->owned = true;
-}
-
-void upb_deflist_uninit(upb_deflist *l) {
-  size_t i;
-  if (l->owned)
-    for(i = 0; i < l->len; i++)
-      upb_def_unref(l->defs[i], l);
-  free(l->defs);
-}
-
-bool upb_deflist_push(upb_deflist *l, upb_def *d) {
-  if(++l->len >= l->size) {
-    size_t new_size = UPB_MAX(l->size, 4);
-    new_size *= 2;
-    l->defs = realloc(l->defs, new_size * sizeof(void *));
-    if (!l->defs) return false;
-    l->size = new_size;
-  }
-  l->defs[l->len - 1] = d;
-  return true;
-}
-
-void upb_deflist_donaterefs(upb_deflist *l, void *owner) {
-  size_t i;
-  assert(l->owned);
-  for (i = 0; i < l->len; i++)
-    upb_def_donateref(l->defs[i], l, owner);
-  l->owned = false;
-}
-
-static upb_def *upb_deflist_last(upb_deflist *l) {
-  return l->defs[l->len-1];
-}
-
-/* Qualify the defname for all defs starting with offset "start" with "str". */
-static void upb_deflist_qualify(upb_deflist *l, char *str, int32_t start) {
-  uint32_t i;
-  for (i = start; i < l->len; i++) {
-    upb_def *def = l->defs[i];
-    char *name = upb_join(str, upb_def_fullname(def));
-    upb_def_setfullname(def, name, NULL);
-    free(name);
-  }
-}
-
-
-/* upb_descreader  ************************************************************/
-
-static upb_msgdef *upb_descreader_top(upb_descreader *r) {
-  int index;
-  assert(r->stack_len > 1);
-  index = r->stack[r->stack_len-1].start - 1;
-  assert(index >= 0);
-  return upb_downcast_msgdef_mutable(r->defs.defs[index]);
-}
-
-static upb_def *upb_descreader_last(upb_descreader *r) {
-  return upb_deflist_last(&r->defs);
-}
-
-/* Start/end handlers for FileDescriptorProto and DescriptorProto (the two
- * entities that have names and can contain sub-definitions. */
-void upb_descreader_startcontainer(upb_descreader *r) {
-  upb_descreader_frame *f = &r->stack[r->stack_len++];
-  f->start = r->defs.len;
-  f->name = NULL;
-}
-
-void upb_descreader_endcontainer(upb_descreader *r) {
-  upb_descreader_frame *f = &r->stack[--r->stack_len];
-  upb_deflist_qualify(&r->defs, f->name, f->start);
-  free(f->name);
-  f->name = NULL;
-}
-
-void upb_descreader_setscopename(upb_descreader *r, char *str) {
-  upb_descreader_frame *f = &r->stack[r->stack_len-1];
-  free(f->name);
-  f->name = str;
-}
-
-/* Handlers for google.protobuf.FileDescriptorProto. */
-static bool file_startmsg(void *r, const void *hd) {
-  UPB_UNUSED(hd);
-  upb_descreader_startcontainer(r);
-  return true;
-}
-
-static bool file_endmsg(void *closure, const void *hd, upb_status *status) {
-  upb_descreader *r = closure;
-  UPB_UNUSED(hd);
-  UPB_UNUSED(status);
-  upb_descreader_endcontainer(r);
-  return true;
-}
-
-static size_t file_onpackage(void *closure, const void *hd, const char *buf,
-                             size_t n, const upb_bufhandle *handle) {
-  upb_descreader *r = closure;
-  UPB_UNUSED(hd);
-  UPB_UNUSED(handle);
-  /* XXX: see comment at the top of the file. */
-  upb_descreader_setscopename(r, upb_strndup(buf, n));
-  return n;
-}
-
-/* Handlers for google.protobuf.EnumValueDescriptorProto. */
-static bool enumval_startmsg(void *closure, const void *hd) {
-  upb_descreader *r = closure;
-  UPB_UNUSED(hd);
-  r->saw_number = false;
-  r->saw_name = false;
-  return true;
-}
-
-static size_t enumval_onname(void *closure, const void *hd, const char *buf,
-                             size_t n, const upb_bufhandle *handle) {
-  upb_descreader *r = closure;
-  UPB_UNUSED(hd);
-  UPB_UNUSED(handle);
-  /* XXX: see comment at the top of the file. */
-  free(r->name);
-  r->name = upb_strndup(buf, n);
-  r->saw_name = true;
-  return n;
-}
-
-static bool enumval_onnumber(void *closure, const void *hd, int32_t val) {
-  upb_descreader *r = closure;
-  UPB_UNUSED(hd);
-  r->number = val;
-  r->saw_number = true;
-  return true;
-}
-
-static bool enumval_endmsg(void *closure, const void *hd, upb_status *status) {
-  upb_descreader *r = closure;
-  upb_enumdef *e;
-  UPB_UNUSED(hd);
-
-  if(!r->saw_number || !r->saw_name) {
-    upb_status_seterrmsg(status, "Enum value missing name or number.");
-    return false;
-  }
-  e = upb_downcast_enumdef_mutable(upb_descreader_last(r));
-  upb_enumdef_addval(e, r->name, r->number, status);
-  free(r->name);
-  r->name = NULL;
-  return true;
-}
-
-
-/* Handlers for google.protobuf.EnumDescriptorProto. */
-static bool enum_startmsg(void *closure, const void *hd) {
-  upb_descreader *r = closure;
-  UPB_UNUSED(hd);
-  upb_deflist_push(&r->defs,
-                   upb_enumdef_upcast_mutable(upb_enumdef_new(&r->defs)));
-  return true;
-}
-
-static bool enum_endmsg(void *closure, const void *hd, upb_status *status) {
-  upb_descreader *r = closure;
-  upb_enumdef *e;
-  UPB_UNUSED(hd);
-
-  e = upb_downcast_enumdef_mutable(upb_descreader_last(r));
-  if (upb_def_fullname(upb_descreader_last(r)) == NULL) {
-    upb_status_seterrmsg(status, "Enum had no name.");
-    return false;
-  }
-  if (upb_enumdef_numvals(e) == 0) {
-    upb_status_seterrmsg(status, "Enum had no values.");
-    return false;
-  }
-  return true;
-}
-
-static size_t enum_onname(void *closure, const void *hd, const char *buf,
-                          size_t n, const upb_bufhandle *handle) {
-  upb_descreader *r = closure;
-  char *fullname = upb_strndup(buf, n);
-  UPB_UNUSED(hd);
-  UPB_UNUSED(handle);
-  /* XXX: see comment at the top of the file. */
-  upb_def_setfullname(upb_descreader_last(r), fullname, NULL);
-  free(fullname);
-  return n;
-}
-
-/* Handlers for google.protobuf.FieldDescriptorProto */
-static bool field_startmsg(void *closure, const void *hd) {
-  upb_descreader *r = closure;
-  UPB_UNUSED(hd);
-  r->f = upb_fielddef_new(&r->defs);
-  free(r->default_string);
-  r->default_string = NULL;
-
-  /* fielddefs default to packed, but descriptors default to non-packed. */
-  upb_fielddef_setpacked(r->f, false);
-  return true;
-}
-
-/* Converts the default value in string "str" into "d".  Passes a ref on str.
- * Returns true on success. */
-static bool parse_default(char *str, upb_fielddef *f) {
-  bool success = true;
-  char *end;
-  switch (upb_fielddef_type(f)) {
-    case UPB_TYPE_INT32: {
-      long val = strtol(str, &end, 0);
-      if (val > INT32_MAX || val < INT32_MIN || errno == ERANGE || *end)
-        success = false;
-      else
-        upb_fielddef_setdefaultint32(f, val);
-      break;
-    }
-    case UPB_TYPE_INT64: {
-      /* XXX: Need to write our own strtoll, since it's not available in c89. */
-      long long val = strtol(str, &end, 0);
-      if (val > INT64_MAX || val < INT64_MIN || errno == ERANGE || *end)
-        success = false;
-      else
-        upb_fielddef_setdefaultint64(f, val);
-      break;
-    }
-    case UPB_TYPE_UINT32: {
-      unsigned long val = strtoul(str, &end, 0);
-      if (val > UINT32_MAX || errno == ERANGE || *end)
-        success = false;
-      else
-        upb_fielddef_setdefaultuint32(f, val);
-      break;
-    }
-    case UPB_TYPE_UINT64: {
-      /* XXX: Need to write our own strtoull, since it's not available in c89. */
-      unsigned long long val = strtoul(str, &end, 0);
-      if (val > UINT64_MAX || errno == ERANGE || *end)
-        success = false;
-      else
-        upb_fielddef_setdefaultuint64(f, val);
-      break;
-    }
-    case UPB_TYPE_DOUBLE: {
-      double val = strtod(str, &end);
-      if (errno == ERANGE || *end)
-        success = false;
-      else
-        upb_fielddef_setdefaultdouble(f, val);
-      break;
-    }
-    case UPB_TYPE_FLOAT: {
-      /* XXX: Need to write our own strtof, since it's not available in c89. */
-      float val = strtod(str, &end);
-      if (errno == ERANGE || *end)
-        success = false;
-      else
-        upb_fielddef_setdefaultfloat(f, val);
-      break;
-    }
-    case UPB_TYPE_BOOL: {
-      if (strcmp(str, "false") == 0)
-        upb_fielddef_setdefaultbool(f, false);
-      else if (strcmp(str, "true") == 0)
-        upb_fielddef_setdefaultbool(f, true);
-      else
-        success = false;
-      break;
-    }
-    default: abort();
-  }
-  return success;
-}
-
-static bool field_endmsg(void *closure, const void *hd, upb_status *status) {
-  upb_descreader *r = closure;
-  upb_fielddef *f = r->f;
-  UPB_UNUSED(hd);
-
-  /* TODO: verify that all required fields were present. */
-  assert(upb_fielddef_number(f) != 0);
-  assert(upb_fielddef_name(f) != NULL);
-  assert((upb_fielddef_subdefname(f) != NULL) == upb_fielddef_hassubdef(f));
-
-  if (r->default_string) {
-    if (upb_fielddef_issubmsg(f)) {
-      upb_status_seterrmsg(status, "Submessages cannot have defaults.");
-      return false;
-    }
-    if (upb_fielddef_isstring(f) || upb_fielddef_type(f) == UPB_TYPE_ENUM) {
-      upb_fielddef_setdefaultcstr(f, r->default_string, NULL);
-    } else {
-      if (r->default_string && !parse_default(r->default_string, f)) {
-        /* We don't worry too much about giving a great error message since the
-         * compiler should have ensured this was correct. */
-        upb_status_seterrmsg(status, "Error converting default value.");
-        return false;
-      }
-    }
-  }
-  return true;
-}
-
-static bool field_onlazy(void *closure, const void *hd, bool val) {
-  upb_descreader *r = closure;
-  UPB_UNUSED(hd);
-
-  upb_fielddef_setlazy(r->f, val);
-  return true;
-}
-
-static bool field_onpacked(void *closure, const void *hd, bool val) {
-  upb_descreader *r = closure;
-  UPB_UNUSED(hd);
-
-  upb_fielddef_setpacked(r->f, val);
-  return true;
-}
-
-static bool field_ontype(void *closure, const void *hd, int32_t val) {
-  upb_descreader *r = closure;
-  UPB_UNUSED(hd);
-
-  upb_fielddef_setdescriptortype(r->f, val);
-  return true;
-}
-
-static bool field_onlabel(void *closure, const void *hd, int32_t val) {
-  upb_descreader *r = closure;
-  UPB_UNUSED(hd);
-
-  upb_fielddef_setlabel(r->f, val);
-  return true;
-}
-
-static bool field_onnumber(void *closure, const void *hd, int32_t val) {
-  upb_descreader *r = closure;
-  bool ok = upb_fielddef_setnumber(r->f, val, NULL);
-  UPB_UNUSED(hd);
-
-  UPB_ASSERT_VAR(ok, ok);
-  return true;
-}
-
-static size_t field_onname(void *closure, const void *hd, const char *buf,
-                           size_t n, const upb_bufhandle *handle) {
-  upb_descreader *r = closure;
-  char *name = upb_strndup(buf, n);
-  UPB_UNUSED(hd);
-  UPB_UNUSED(handle);
-
-  /* XXX: see comment at the top of the file. */
-  upb_fielddef_setname(r->f, name, NULL);
-  free(name);
-  return n;
-}
-
-static size_t field_ontypename(void *closure, const void *hd, const char *buf,
-                               size_t n, const upb_bufhandle *handle) {
-  upb_descreader *r = closure;
-  char *name = upb_strndup(buf, n);
-  UPB_UNUSED(hd);
-  UPB_UNUSED(handle);
-
-  /* XXX: see comment at the top of the file. */
-  upb_fielddef_setsubdefname(r->f, name, NULL);
-  free(name);
-  return n;
-}
-
-static size_t field_onextendee(void *closure, const void *hd, const char *buf,
-                               size_t n, const upb_bufhandle *handle) {
-  upb_descreader *r = closure;
-  char *name = upb_strndup(buf, n);
-  UPB_UNUSED(hd);
-  UPB_UNUSED(handle);
-
-  /* XXX: see comment at the top of the file. */
-  upb_fielddef_setcontainingtypename(r->f, name, NULL);
-  free(name);
-  return n;
-}
-
-static size_t field_ondefaultval(void *closure, const void *hd, const char *buf,
-                                 size_t n, const upb_bufhandle *handle) {
-  upb_descreader *r = closure;
-  UPB_UNUSED(hd);
-  UPB_UNUSED(handle);
-
-  /* Have to convert from string to the correct type, but we might not know the
-   * type yet, so we save it as a string until the end of the field.
-   * XXX: see comment at the top of the file. */
-  free(r->default_string);
-  r->default_string = upb_strndup(buf, n);
-  return n;
-}
-
-/* Handlers for google.protobuf.DescriptorProto (representing a message). */
-static bool msg_startmsg(void *closure, const void *hd) {
-  upb_descreader *r = closure;
-  UPB_UNUSED(hd);
-
-  upb_deflist_push(&r->defs,
-                   upb_msgdef_upcast_mutable(upb_msgdef_new(&r->defs)));
-  upb_descreader_startcontainer(r);
-  return true;
-}
-
-static bool msg_endmsg(void *closure, const void *hd, upb_status *status) {
-  upb_descreader *r = closure;
-  upb_msgdef *m = upb_descreader_top(r);
-  UPB_UNUSED(hd);
-
-  if(!upb_def_fullname(upb_msgdef_upcast_mutable(m))) {
-    upb_status_seterrmsg(status, "Encountered message with no name.");
-    return false;
-  }
-  upb_descreader_endcontainer(r);
-  return true;
-}
-
-static size_t msg_onname(void *closure, const void *hd, const char *buf,
-                         size_t n, const upb_bufhandle *handle) {
-  upb_descreader *r = closure;
-  upb_msgdef *m = upb_descreader_top(r);
-  /* XXX: see comment at the top of the file. */
-  char *name = upb_strndup(buf, n);
-  UPB_UNUSED(hd);
-  UPB_UNUSED(handle);
-
-  upb_def_setfullname(upb_msgdef_upcast_mutable(m), name, NULL);
-  upb_descreader_setscopename(r, name);  /* Passes ownership of name. */
-  return n;
-}
-
-static bool msg_onendfield(void *closure, const void *hd) {
-  upb_descreader *r = closure;
-  upb_msgdef *m = upb_descreader_top(r);
-  UPB_UNUSED(hd);
-
-  upb_msgdef_addfield(m, r->f, &r->defs, NULL);
-  r->f = NULL;
-  return true;
-}
-
-static bool pushextension(void *closure, const void *hd) {
-  upb_descreader *r = closure;
-  UPB_UNUSED(hd);
-
-  assert(upb_fielddef_containingtypename(r->f));
-  upb_fielddef_setisextension(r->f, true);
-  upb_deflist_push(&r->defs, upb_fielddef_upcast_mutable(r->f));
-  r->f = NULL;
-  return true;
-}
-
-#define D(name) upbdefs_google_protobuf_ ## name(s)
-
-static void reghandlers(const void *closure, upb_handlers *h) {
-  const upb_symtab *s = closure;
-  const upb_msgdef *m = upb_handlers_msgdef(h);
-
-  if (m == D(DescriptorProto)) {
-    upb_handlers_setstartmsg(h, &msg_startmsg, NULL);
-    upb_handlers_setendmsg(h, &msg_endmsg, NULL);
-    upb_handlers_setstring(h, D(DescriptorProto_name), &msg_onname, NULL);
-    upb_handlers_setendsubmsg(h, D(DescriptorProto_field), &msg_onendfield,
-                              NULL);
-    upb_handlers_setendsubmsg(h, D(DescriptorProto_extension), &pushextension,
-                              NULL);
-  } else if (m == D(FileDescriptorProto)) {
-    upb_handlers_setstartmsg(h, &file_startmsg, NULL);
-    upb_handlers_setendmsg(h, &file_endmsg, NULL);
-    upb_handlers_setstring(h, D(FileDescriptorProto_package), &file_onpackage,
-                           NULL);
-    upb_handlers_setendsubmsg(h, D(FileDescriptorProto_extension), &pushextension,
-                              NULL);
-  } else if (m == D(EnumValueDescriptorProto)) {
-    upb_handlers_setstartmsg(h, &enumval_startmsg, NULL);
-    upb_handlers_setendmsg(h, &enumval_endmsg, NULL);
-    upb_handlers_setstring(h, D(EnumValueDescriptorProto_name), &enumval_onname, NULL);
-    upb_handlers_setint32(h, D(EnumValueDescriptorProto_number), &enumval_onnumber,
-                          NULL);
-  } else if (m == D(EnumDescriptorProto)) {
-    upb_handlers_setstartmsg(h, &enum_startmsg, NULL);
-    upb_handlers_setendmsg(h, &enum_endmsg, NULL);
-    upb_handlers_setstring(h, D(EnumDescriptorProto_name), &enum_onname, NULL);
-  } else if (m == D(FieldDescriptorProto)) {
-    upb_handlers_setstartmsg(h, &field_startmsg, NULL);
-    upb_handlers_setendmsg(h, &field_endmsg, NULL);
-    upb_handlers_setint32(h, D(FieldDescriptorProto_type), &field_ontype,
-                          NULL);
-    upb_handlers_setint32(h, D(FieldDescriptorProto_label), &field_onlabel,
-                          NULL);
-    upb_handlers_setint32(h, D(FieldDescriptorProto_number), &field_onnumber,
-                          NULL);
-    upb_handlers_setstring(h, D(FieldDescriptorProto_name), &field_onname,
-                           NULL);
-    upb_handlers_setstring(h, D(FieldDescriptorProto_type_name),
-                           &field_ontypename, NULL);
-    upb_handlers_setstring(h, D(FieldDescriptorProto_extendee),
-                           &field_onextendee, NULL);
-    upb_handlers_setstring(h, D(FieldDescriptorProto_default_value),
-                           &field_ondefaultval, NULL);
-  } else if (m == D(FieldOptions)) {
-    upb_handlers_setbool(h, D(FieldOptions_lazy), &field_onlazy, NULL);
-    upb_handlers_setbool(h, D(FieldOptions_packed), &field_onpacked, NULL);
-  }
-}
-
-#undef D
-
-void descreader_cleanup(void *_r) {
-  upb_descreader *r = _r;
-  free(r->name);
-  upb_deflist_uninit(&r->defs);
-  free(r->default_string);
-  while (r->stack_len > 0) {
-    upb_descreader_frame *f = &r->stack[--r->stack_len];
-    free(f->name);
-  }
-}
-
-
-/* Public API  ****************************************************************/
-
-upb_descreader *upb_descreader_create(upb_env *e, const upb_handlers *h) {
-  upb_descreader *r = upb_env_malloc(e, sizeof(upb_descreader));
-  if (!r || !upb_env_addcleanup(e, descreader_cleanup, r)) {
-    return NULL;
-  }
-
-  upb_deflist_init(&r->defs);
-  upb_sink_reset(upb_descreader_input(r), h, r);
-  r->stack_len = 0;
-  r->name = NULL;
-  r->default_string = NULL;
-
-  return r;
-}
-
-upb_def **upb_descreader_getdefs(upb_descreader *r, void *owner, int *n) {
-  *n = r->defs.len;
-  upb_deflist_donaterefs(&r->defs, owner);
-  return r->defs.defs;
-}
-
-upb_sink *upb_descreader_input(upb_descreader *r) {
-  return &r->sink;
-}
-
-const upb_handlers *upb_descreader_newhandlers(const void *owner) {
-  const upb_symtab *s = upbdefs_google_protobuf_descriptor(&s);
-  const upb_handlers *h = upb_handlers_newfrozen(
-      upbdefs_google_protobuf_FileDescriptorSet(s), owner, reghandlers, s);
-  upb_symtab_unref(s, &s);
-  return h;
-}
-/*
-** protobuf decoder bytecode compiler
-**
-** Code to compile a upb::Handlers into bytecode for decoding a protobuf
-** according to that specific schema and destination handlers.
-**
-** Compiling to bytecode is always the first step.  If we are using the
-** interpreted decoder we leave it as bytecode and interpret that.  If we are
-** using a JIT decoder we use a code generator to turn the bytecode into native
-** code, LLVM IR, etc.
-**
-** Bytecode definition is in decoder.int.h.
-*/
-
-#include <stdarg.h>
-
-#ifdef UPB_DUMP_BYTECODE
-#include <stdio.h>
-#endif
-
-#define MAXLABEL 5
-#define EMPTYLABEL -1
-
-/* mgroup *********************************************************************/
-
-static void freegroup(upb_refcounted *r) {
-  mgroup *g = (mgroup*)r;
-  upb_inttable_uninit(&g->methods);
-#ifdef UPB_USE_JIT_X64
-  upb_pbdecoder_freejit(g);
-#endif
-  free(g->bytecode);
-  free(g);
-}
-
-static void visitgroup(const upb_refcounted *r, upb_refcounted_visit *visit,
-                       void *closure) {
-  const mgroup *g = (const mgroup*)r;
-  upb_inttable_iter i;
-  upb_inttable_begin(&i, &g->methods);
-  for(; !upb_inttable_done(&i); upb_inttable_next(&i)) {
-    upb_pbdecodermethod *method = upb_value_getptr(upb_inttable_iter_value(&i));
-    visit(r, upb_pbdecodermethod_upcast(method), closure);
-  }
-}
-
-mgroup *newgroup(const void *owner) {
-  mgroup *g = malloc(sizeof(*g));
-  static const struct upb_refcounted_vtbl vtbl = {visitgroup, freegroup};
-  upb_refcounted_init(mgroup_upcast_mutable(g), &vtbl, owner);
-  upb_inttable_init(&g->methods, UPB_CTYPE_PTR);
-  g->bytecode = NULL;
-  g->bytecode_end = NULL;
-  return g;
-}
-
-
-/* upb_pbdecodermethod ********************************************************/
-
-static void freemethod(upb_refcounted *r) {
-  upb_pbdecodermethod *method = (upb_pbdecodermethod*)r;
-
-  if (method->dest_handlers_) {
-    upb_handlers_unref(method->dest_handlers_, method);
-  }
-
-  upb_inttable_uninit(&method->dispatch);
-  free(method);
-}
-
-static void visitmethod(const upb_refcounted *r, upb_refcounted_visit *visit,
-                        void *closure) {
-  const upb_pbdecodermethod *m = (const upb_pbdecodermethod*)r;
-  visit(r, m->group, closure);
-}
-
-static upb_pbdecodermethod *newmethod(const upb_handlers *dest_handlers,
-                                      mgroup *group) {
-  static const struct upb_refcounted_vtbl vtbl = {visitmethod, freemethod};
-  upb_pbdecodermethod *ret = malloc(sizeof(*ret));
-  upb_refcounted_init(upb_pbdecodermethod_upcast_mutable(ret), &vtbl, &ret);
-  upb_byteshandler_init(&ret->input_handler_);
-
-  /* The method references the group and vice-versa, in a circular reference. */
-  upb_ref2(ret, group);
-  upb_ref2(group, ret);
-  upb_inttable_insertptr(&group->methods, dest_handlers, upb_value_ptr(ret));
-  upb_pbdecodermethod_unref(ret, &ret);
-
-  ret->group = mgroup_upcast_mutable(group);
-  ret->dest_handlers_ = dest_handlers;
-  ret->is_native_ = false;  /* If we JIT, it will update this later. */
-  upb_inttable_init(&ret->dispatch, UPB_CTYPE_UINT64);
-
-  if (ret->dest_handlers_) {
-    upb_handlers_ref(ret->dest_handlers_, ret);
-  }
-  return ret;
-}
-
-const upb_handlers *upb_pbdecodermethod_desthandlers(
-    const upb_pbdecodermethod *m) {
-  return m->dest_handlers_;
-}
-
-const upb_byteshandler *upb_pbdecodermethod_inputhandler(
-    const upb_pbdecodermethod *m) {
-  return &m->input_handler_;
-}
-
-bool upb_pbdecodermethod_isnative(const upb_pbdecodermethod *m) {
-  return m->is_native_;
-}
-
-const upb_pbdecodermethod *upb_pbdecodermethod_new(
-    const upb_pbdecodermethodopts *opts, const void *owner) {
-  const upb_pbdecodermethod *ret;
-  upb_pbcodecache cache;
-
-  upb_pbcodecache_init(&cache);
-  ret = upb_pbcodecache_getdecodermethod(&cache, opts);
-  upb_pbdecodermethod_ref(ret, owner);
-  upb_pbcodecache_uninit(&cache);
-  return ret;
-}
-
-
-/* bytecode compiler **********************************************************/
-
-/* Data used only at compilation time. */
-typedef struct {
-  mgroup *group;
-
-  uint32_t *pc;
-  int fwd_labels[MAXLABEL];
-  int back_labels[MAXLABEL];
-
-  /* For fields marked "lazy", parse them lazily or eagerly? */
-  bool lazy;
-} compiler;
-
-static compiler *newcompiler(mgroup *group, bool lazy) {
-  compiler *ret = malloc(sizeof(*ret));
-  int i;
-
-  ret->group = group;
-  ret->lazy = lazy;
-  for (i = 0; i < MAXLABEL; i++) {
-    ret->fwd_labels[i] = EMPTYLABEL;
-    ret->back_labels[i] = EMPTYLABEL;
-  }
-  return ret;
-}
-
-static void freecompiler(compiler *c) {
-  free(c);
-}
-
-const size_t ptr_words = sizeof(void*) / sizeof(uint32_t);
-
-/* How many words an instruction is. */
-static int instruction_len(uint32_t instr) {
-  switch (getop(instr)) {
-    case OP_SETDISPATCH: return 1 + ptr_words;
-    case OP_TAGN: return 3;
-    case OP_SETBIGGROUPNUM: return 2;
-    default: return 1;
-  }
-}
-
-bool op_has_longofs(int32_t instruction) {
-  switch (getop(instruction)) {
-    case OP_CALL:
-    case OP_BRANCH:
-    case OP_CHECKDELIM:
-      return true;
-    /* The "tag" instructions only have 8 bytes available for the jump target,
-     * but that is ok because these opcodes only require short jumps. */
-    case OP_TAG1:
-    case OP_TAG2:
-    case OP_TAGN:
-      return false;
-    default:
-      assert(false);
-      return false;
-  }
-}
-
-static int32_t getofs(uint32_t instruction) {
-  if (op_has_longofs(instruction)) {
-    return (int32_t)instruction >> 8;
-  } else {
-    return (int8_t)(instruction >> 8);
-  }
-}
-
-static void setofs(uint32_t *instruction, int32_t ofs) {
-  if (op_has_longofs(*instruction)) {
-    *instruction = getop(*instruction) | ofs << 8;
-  } else {
-    *instruction = (*instruction & ~0xff00) | ((ofs & 0xff) << 8);
-  }
-  assert(getofs(*instruction) == ofs);  /* Would fail in cases of overflow. */
-}
-
-static uint32_t pcofs(compiler *c) { return c->pc - c->group->bytecode; }
-
-/* Defines a local label at the current PC location.  All previous forward
- * references are updated to point to this location.  The location is noted
- * for any future backward references. */
-static void label(compiler *c, unsigned int label) {
-  int val;
-  uint32_t *codep;
-
-  assert(label < MAXLABEL);
-  val = c->fwd_labels[label];
-  codep = (val == EMPTYLABEL) ? NULL : c->group->bytecode + val;
-  while (codep) {
-    int ofs = getofs(*codep);
-    setofs(codep, c->pc - codep - instruction_len(*codep));
-    codep = ofs ? codep + ofs : NULL;
-  }
-  c->fwd_labels[label] = EMPTYLABEL;
-  c->back_labels[label] = pcofs(c);
-}
-
-/* Creates a reference to a numbered label; either a forward reference
- * (positive arg) or backward reference (negative arg).  For forward references
- * the value returned now is actually a "next" pointer into a linked list of all
- * instructions that use this label and will be patched later when the label is
- * defined with label().
- *
- * The returned value is the offset that should be written into the instruction.
- */
-static int32_t labelref(compiler *c, int label) {
-  assert(label < MAXLABEL);
-  if (label == LABEL_DISPATCH) {
-    /* No resolving required. */
-    return 0;
-  } else if (label < 0) {
-    /* Backward local label.  Relative to the next instruction. */
-    uint32_t from = (c->pc + 1) - c->group->bytecode;
-    return c->back_labels[-label] - from;
-  } else {
-    /* Forward local label: prepend to (possibly-empty) linked list. */
-    int *lptr = &c->fwd_labels[label];
-    int32_t ret = (*lptr == EMPTYLABEL) ? 0 : *lptr - pcofs(c);
-    *lptr = pcofs(c);
-    return ret;
-  }
-}
-
-static void put32(compiler *c, uint32_t v) {
-  mgroup *g = c->group;
-  if (c->pc == g->bytecode_end) {
-    int ofs = pcofs(c);
-    size_t oldsize = g->bytecode_end - g->bytecode;
-    size_t newsize = UPB_MAX(oldsize * 2, 64);
-    /* TODO(haberman): handle OOM. */
-    g->bytecode = realloc(g->bytecode, newsize * sizeof(uint32_t));
-    g->bytecode_end = g->bytecode + newsize;
-    c->pc = g->bytecode + ofs;
-  }
-  *c->pc++ = v;
-}
-
-static void putop(compiler *c, opcode op, ...) {
-  va_list ap;
-  va_start(ap, op);
-
-  switch (op) {
-    case OP_SETDISPATCH: {
-      uintptr_t ptr = (uintptr_t)va_arg(ap, void*);
-      put32(c, OP_SETDISPATCH);
-      put32(c, ptr);
-      if (sizeof(uintptr_t) > sizeof(uint32_t))
-        put32(c, (uint64_t)ptr >> 32);
-      break;
-    }
-    case OP_STARTMSG:
-    case OP_ENDMSG:
-    case OP_PUSHLENDELIM:
-    case OP_POP:
-    case OP_SETDELIM:
-    case OP_HALT:
-    case OP_RET:
-    case OP_DISPATCH:
-      put32(c, op);
-      break;
-    case OP_PARSE_DOUBLE:
-    case OP_PARSE_FLOAT:
-    case OP_PARSE_INT64:
-    case OP_PARSE_UINT64:
-    case OP_PARSE_INT32:
-    case OP_PARSE_FIXED64:
-    case OP_PARSE_FIXED32:
-    case OP_PARSE_BOOL:
-    case OP_PARSE_UINT32:
-    case OP_PARSE_SFIXED32:
-    case OP_PARSE_SFIXED64:
-    case OP_PARSE_SINT32:
-    case OP_PARSE_SINT64:
-    case OP_STARTSEQ:
-    case OP_ENDSEQ:
-    case OP_STARTSUBMSG:
-    case OP_ENDSUBMSG:
-    case OP_STARTSTR:
-    case OP_STRING:
-    case OP_ENDSTR:
-    case OP_PUSHTAGDELIM:
-      put32(c, op | va_arg(ap, upb_selector_t) << 8);
-      break;
-    case OP_SETBIGGROUPNUM:
-      put32(c, op);
-      put32(c, va_arg(ap, int));
-      break;
-    case OP_CALL: {
-      const upb_pbdecodermethod *method = va_arg(ap, upb_pbdecodermethod *);
-      put32(c, op | (method->code_base.ofs - (pcofs(c) + 1)) << 8);
-      break;
-    }
-    case OP_CHECKDELIM:
-    case OP_BRANCH: {
-      uint32_t instruction = op;
-      int label = va_arg(ap, int);
-      setofs(&instruction, labelref(c, label));
-      put32(c, instruction);
-      break;
-    }
-    case OP_TAG1:
-    case OP_TAG2: {
-      int label = va_arg(ap, int);
-      uint64_t tag = va_arg(ap, uint64_t);
-      uint32_t instruction = op | (tag << 16);
-      assert(tag <= 0xffff);
-      setofs(&instruction, labelref(c, label));
-      put32(c, instruction);
-      break;
-    }
-    case OP_TAGN: {
-      int label = va_arg(ap, int);
-      uint64_t tag = va_arg(ap, uint64_t);
-      uint32_t instruction = op | (upb_value_size(tag) << 16);
-      setofs(&instruction, labelref(c, label));
-      put32(c, instruction);
-      put32(c, tag);
-      put32(c, tag >> 32);
-      break;
-    }
-  }
-
-  va_end(ap);
-}
-
-#if defined(UPB_USE_JIT_X64) || defined(UPB_DUMP_BYTECODE)
-
-const char *upb_pbdecoder_getopname(unsigned int op) {
-#define QUOTE(x) #x
-#define EXPAND_AND_QUOTE(x) QUOTE(x)
-#define OPNAME(x) OP_##x
-#define OP(x) case OPNAME(x): return EXPAND_AND_QUOTE(OPNAME(x));
-#define T(x) OP(PARSE_##x)
-  /* Keep in sync with list in decoder.int.h. */
-  switch ((opcode)op) {
-    T(DOUBLE) T(FLOAT) T(INT64) T(UINT64) T(INT32) T(FIXED64) T(FIXED32)
-    T(BOOL) T(UINT32) T(SFIXED32) T(SFIXED64) T(SINT32) T(SINT64)
-    OP(STARTMSG) OP(ENDMSG) OP(STARTSEQ) OP(ENDSEQ) OP(STARTSUBMSG)
-    OP(ENDSUBMSG) OP(STARTSTR) OP(STRING) OP(ENDSTR) OP(CALL) OP(RET)
-    OP(PUSHLENDELIM) OP(PUSHTAGDELIM) OP(SETDELIM) OP(CHECKDELIM)
-    OP(BRANCH) OP(TAG1) OP(TAG2) OP(TAGN) OP(SETDISPATCH) OP(POP)
-    OP(SETBIGGROUPNUM) OP(DISPATCH) OP(HALT)
-  }
-  return "<unknown op>";
-#undef OP
-#undef T
-}
-
-#endif
-
-#ifdef UPB_DUMP_BYTECODE
-
-static void dumpbc(uint32_t *p, uint32_t *end, FILE *f) {
-
-  uint32_t *begin = p;
-
-  while (p < end) {
-    fprintf(f, "%p  %8tx", p, p - begin);
-    uint32_t instr = *p++;
-    uint8_t op = getop(instr);
-    fprintf(f, " %s", upb_pbdecoder_getopname(op));
-    switch ((opcode)op) {
-      case OP_SETDISPATCH: {
-        const upb_inttable *dispatch;
-        memcpy(&dispatch, p, sizeof(void*));
-        p += ptr_words;
-        const upb_pbdecodermethod *method =
-            (void *)((char *)dispatch -
-                     offsetof(upb_pbdecodermethod, dispatch));
-        fprintf(f, " %s", upb_msgdef_fullname(
-                              upb_handlers_msgdef(method->dest_handlers_)));
-        break;
-      }
-      case OP_DISPATCH:
-      case OP_STARTMSG:
-      case OP_ENDMSG:
-      case OP_PUSHLENDELIM:
-      case OP_POP:
-      case OP_SETDELIM:
-      case OP_HALT:
-      case OP_RET:
-        break;
-      case OP_PARSE_DOUBLE:
-      case OP_PARSE_FLOAT:
-      case OP_PARSE_INT64:
-      case OP_PARSE_UINT64:
-      case OP_PARSE_INT32:
-      case OP_PARSE_FIXED64:
-      case OP_PARSE_FIXED32:
-      case OP_PARSE_BOOL:
-      case OP_PARSE_UINT32:
-      case OP_PARSE_SFIXED32:
-      case OP_PARSE_SFIXED64:
-      case OP_PARSE_SINT32:
-      case OP_PARSE_SINT64:
-      case OP_STARTSEQ:
-      case OP_ENDSEQ:
-      case OP_STARTSUBMSG:
-      case OP_ENDSUBMSG:
-      case OP_STARTSTR:
-      case OP_STRING:
-      case OP_ENDSTR:
-      case OP_PUSHTAGDELIM:
-        fprintf(f, " %d", instr >> 8);
-        break;
-      case OP_SETBIGGROUPNUM:
-        fprintf(f, " %d", *p++);
-        break;
-      case OP_CHECKDELIM:
-      case OP_CALL:
-      case OP_BRANCH:
-        fprintf(f, " =>0x%tx", p + getofs(instr) - begin);
-        break;
-      case OP_TAG1:
-      case OP_TAG2: {
-        fprintf(f, " tag:0x%x", instr >> 16);
-        if (getofs(instr)) {
-          fprintf(f, " =>0x%tx", p + getofs(instr) - begin);
-        }
-        break;
-      }
-      case OP_TAGN: {
-        uint64_t tag = *p++;
-        tag |= (uint64_t)*p++ << 32;
-        fprintf(f, " tag:0x%llx", (long long)tag);
-        fprintf(f, " n:%d", instr >> 16);
-        if (getofs(instr)) {
-          fprintf(f, " =>0x%tx", p + getofs(instr) - begin);
-        }
-        break;
-      }
-    }
-    fputs("\n", f);
-  }
-}
-
-#endif
-
-static uint64_t get_encoded_tag(const upb_fielddef *f, int wire_type) {
-  uint32_t tag = (upb_fielddef_number(f) << 3) | wire_type;
-  uint64_t encoded_tag = upb_vencode32(tag);
-  /* No tag should be greater than 5 bytes. */
-  assert(encoded_tag <= 0xffffffffff);
-  return encoded_tag;
-}
-
-static void putchecktag(compiler *c, const upb_fielddef *f,
-                        int wire_type, int dest) {
-  uint64_t tag = get_encoded_tag(f, wire_type);
-  switch (upb_value_size(tag)) {
-    case 1:
-      putop(c, OP_TAG1, dest, tag);
-      break;
-    case 2:
-      putop(c, OP_TAG2, dest, tag);
-      break;
-    default:
-      putop(c, OP_TAGN, dest, tag);
-      break;
-  }
-}
-
-static upb_selector_t getsel(const upb_fielddef *f, upb_handlertype_t type) {
-  upb_selector_t selector;
-  bool ok = upb_handlers_getselector(f, type, &selector);
-  UPB_ASSERT_VAR(ok, ok);
-  return selector;
-}
-
-/* Takes an existing, primary dispatch table entry and repacks it with a
- * different alternate wire type.  Called when we are inserting a secondary
- * dispatch table entry for an alternate wire type. */
-static uint64_t repack(uint64_t dispatch, int new_wt2) {
-  uint64_t ofs;
-  uint8_t wt1;
-  uint8_t old_wt2;
-  upb_pbdecoder_unpackdispatch(dispatch, &ofs, &wt1, &old_wt2);
-  assert(old_wt2 == NO_WIRE_TYPE);  /* wt2 should not be set yet. */
-  return upb_pbdecoder_packdispatch(ofs, wt1, new_wt2);
-}
-
-/* Marks the current bytecode position as the dispatch target for this message,
- * field, and wire type. */
-static void dispatchtarget(compiler *c, upb_pbdecodermethod *method,
-                           const upb_fielddef *f, int wire_type) {
-  /* Offset is relative to msg base. */
-  uint64_t ofs = pcofs(c) - method->code_base.ofs;
-  uint32_t fn = upb_fielddef_number(f);
-  upb_inttable *d = &method->dispatch;
-  upb_value v;
-  if (upb_inttable_remove(d, fn, &v)) {
-    /* TODO: prioritize based on packed setting in .proto file. */
-    uint64_t repacked = repack(upb_value_getuint64(v), wire_type);
-    upb_inttable_insert(d, fn, upb_value_uint64(repacked));
-    upb_inttable_insert(d, fn + UPB_MAX_FIELDNUMBER, upb_value_uint64(ofs));
-  } else {
-    uint64_t val = upb_pbdecoder_packdispatch(ofs, wire_type, NO_WIRE_TYPE);
-    upb_inttable_insert(d, fn, upb_value_uint64(val));
-  }
-}
-
-static void putpush(compiler *c, const upb_fielddef *f) {
-  if (upb_fielddef_descriptortype(f) == UPB_DESCRIPTOR_TYPE_MESSAGE) {
-    putop(c, OP_PUSHLENDELIM);
-  } else {
-    uint32_t fn = upb_fielddef_number(f);
-    if (fn >= 1 << 24) {
-      putop(c, OP_PUSHTAGDELIM, 0);
-      putop(c, OP_SETBIGGROUPNUM, fn);
-    } else {
-      putop(c, OP_PUSHTAGDELIM, fn);
-    }
-  }
-}
-
-static upb_pbdecodermethod *find_submethod(const compiler *c,
-                                           const upb_pbdecodermethod *method,
-                                           const upb_fielddef *f) {
-  const upb_handlers *sub =
-      upb_handlers_getsubhandlers(method->dest_handlers_, f);
-  upb_value v;
-  return upb_inttable_lookupptr(&c->group->methods, sub, &v)
-             ? upb_value_getptr(v)
-             : NULL;
-}
-
-static void putsel(compiler *c, opcode op, upb_selector_t sel,
-                   const upb_handlers *h) {
-  if (upb_handlers_gethandler(h, sel)) {
-    putop(c, op, sel);
-  }
-}
-
-/* Puts an opcode to call a callback, but only if a callback actually exists for
- * this field and handler type. */
-static void maybeput(compiler *c, opcode op, const upb_handlers *h,
-                     const upb_fielddef *f, upb_handlertype_t type) {
-  putsel(c, op, getsel(f, type), h);
-}
-
-static bool haslazyhandlers(const upb_handlers *h, const upb_fielddef *f) {
-  if (!upb_fielddef_lazy(f))
-    return false;
-
-  return upb_handlers_gethandler(h, getsel(f, UPB_HANDLER_STARTSTR)) ||
-         upb_handlers_gethandler(h, getsel(f, UPB_HANDLER_STRING)) ||
-         upb_handlers_gethandler(h, getsel(f, UPB_HANDLER_ENDSTR));
-}
-
-
-/* bytecode compiler code generation ******************************************/
-
-/* Symbolic names for our local labels. */
-#define LABEL_LOOPSTART 1  /* Top of a repeated field loop. */
-#define LABEL_LOOPBREAK 2  /* To jump out of a repeated loop */
-#define LABEL_FIELD     3  /* Jump backward to find the most recent field. */
-#define LABEL_ENDMSG    4  /* To reach the OP_ENDMSG instr for this msg. */
-
-/* Generates bytecode to parse a single non-lazy message field. */
-static void generate_msgfield(compiler *c, const upb_fielddef *f,
-                              upb_pbdecodermethod *method) {
-  const upb_handlers *h = upb_pbdecodermethod_desthandlers(method);
-  const upb_pbdecodermethod *sub_m = find_submethod(c, method, f);
-  int wire_type;
-
-  if (!sub_m) {
-    /* Don't emit any code for this field at all; it will be parsed as an
-     * unknown field. */
-    return;
-  }
-
-  label(c, LABEL_FIELD);
-
-  wire_type =
-      (upb_fielddef_descriptortype(f) == UPB_DESCRIPTOR_TYPE_MESSAGE)
-          ? UPB_WIRE_TYPE_DELIMITED
-          : UPB_WIRE_TYPE_START_GROUP;
-
-  if (upb_fielddef_isseq(f)) {
-    putop(c, OP_CHECKDELIM, LABEL_ENDMSG);
-    putchecktag(c, f, wire_type, LABEL_DISPATCH);
-   dispatchtarget(c, method, f, wire_type);
-    putop(c, OP_PUSHTAGDELIM, 0);
-    putop(c, OP_STARTSEQ, getsel(f, UPB_HANDLER_STARTSEQ));
-   label(c, LABEL_LOOPSTART);
-    putpush(c, f);
-    putop(c, OP_STARTSUBMSG, getsel(f, UPB_HANDLER_STARTSUBMSG));
-    putop(c, OP_CALL, sub_m);
-    putop(c, OP_POP);
-    maybeput(c, OP_ENDSUBMSG, h, f, UPB_HANDLER_ENDSUBMSG);
-    if (wire_type == UPB_WIRE_TYPE_DELIMITED) {
-      putop(c, OP_SETDELIM);
-    }
-    putop(c, OP_CHECKDELIM, LABEL_LOOPBREAK);
-    putchecktag(c, f, wire_type, LABEL_LOOPBREAK);
-    putop(c, OP_BRANCH, -LABEL_LOOPSTART);
-   label(c, LABEL_LOOPBREAK);
-    putop(c, OP_POP);
-    maybeput(c, OP_ENDSEQ, h, f, UPB_HANDLER_ENDSEQ);
-  } else {
-    putop(c, OP_CHECKDELIM, LABEL_ENDMSG);
-    putchecktag(c, f, wire_type, LABEL_DISPATCH);
-   dispatchtarget(c, method, f, wire_type);
-    putpush(c, f);
-    putop(c, OP_STARTSUBMSG, getsel(f, UPB_HANDLER_STARTSUBMSG));
-    putop(c, OP_CALL, sub_m);
-    putop(c, OP_POP);
-    maybeput(c, OP_ENDSUBMSG, h, f, UPB_HANDLER_ENDSUBMSG);
-    if (wire_type == UPB_WIRE_TYPE_DELIMITED) {
-      putop(c, OP_SETDELIM);
-    }
-  }
-}
-
-/* Generates bytecode to parse a single string or lazy submessage field. */
-static void generate_delimfield(compiler *c, const upb_fielddef *f,
-                                upb_pbdecodermethod *method) {
-  const upb_handlers *h = upb_pbdecodermethod_desthandlers(method);
-
-  label(c, LABEL_FIELD);
-  if (upb_fielddef_isseq(f)) {
-    putop(c, OP_CHECKDELIM, LABEL_ENDMSG);
-    putchecktag(c, f, UPB_WIRE_TYPE_DELIMITED, LABEL_DISPATCH);
-   dispatchtarget(c, method, f, UPB_WIRE_TYPE_DELIMITED);
-    putop(c, OP_PUSHTAGDELIM, 0);
-    putop(c, OP_STARTSEQ, getsel(f, UPB_HANDLER_STARTSEQ));
-   label(c, LABEL_LOOPSTART);
-    putop(c, OP_PUSHLENDELIM);
-    putop(c, OP_STARTSTR, getsel(f, UPB_HANDLER_STARTSTR));
-    /* Need to emit even if no handler to skip past the string. */
-    putop(c, OP_STRING, getsel(f, UPB_HANDLER_STRING));
-    putop(c, OP_POP);
-    maybeput(c, OP_ENDSTR, h, f, UPB_HANDLER_ENDSTR);
-    putop(c, OP_SETDELIM);
-    putop(c, OP_CHECKDELIM, LABEL_LOOPBREAK);
-    putchecktag(c, f, UPB_WIRE_TYPE_DELIMITED, LABEL_LOOPBREAK);
-    putop(c, OP_BRANCH, -LABEL_LOOPSTART);
-   label(c, LABEL_LOOPBREAK);
-    putop(c, OP_POP);
-    maybeput(c, OP_ENDSEQ, h, f, UPB_HANDLER_ENDSEQ);
-  } else {
-    putop(c, OP_CHECKDELIM, LABEL_ENDMSG);
-    putchecktag(c, f, UPB_WIRE_TYPE_DELIMITED, LABEL_DISPATCH);
-   dispatchtarget(c, method, f, UPB_WIRE_TYPE_DELIMITED);
-    putop(c, OP_PUSHLENDELIM);
-    putop(c, OP_STARTSTR, getsel(f, UPB_HANDLER_STARTSTR));
-    putop(c, OP_STRING, getsel(f, UPB_HANDLER_STRING));
-    putop(c, OP_POP);
-    maybeput(c, OP_ENDSTR, h, f, UPB_HANDLER_ENDSTR);
-    putop(c, OP_SETDELIM);
-  }
-}
-
-/* Generates bytecode to parse a single primitive field. */
-static void generate_primitivefield(compiler *c, const upb_fielddef *f,
-                                    upb_pbdecodermethod *method) {
-  const upb_handlers *h = upb_pbdecodermethod_desthandlers(method);
-  upb_descriptortype_t descriptor_type = upb_fielddef_descriptortype(f);
-  opcode parse_type;
-  upb_selector_t sel;
-  int wire_type;
-
-  label(c, LABEL_FIELD);
-
-  /* From a decoding perspective, ENUM is the same as INT32. */
-  if (descriptor_type == UPB_DESCRIPTOR_TYPE_ENUM)
-    descriptor_type = UPB_DESCRIPTOR_TYPE_INT32;
-
-  parse_type = (opcode)descriptor_type;
-
-  /* TODO(haberman): generate packed or non-packed first depending on "packed"
-   * setting in the fielddef.  This will favor (in speed) whichever was
-   * specified. */
-
-  assert((int)parse_type >= 0 && parse_type <= OP_MAX);
-  sel = getsel(f, upb_handlers_getprimitivehandlertype(f));
-  wire_type = upb_pb_native_wire_types[upb_fielddef_descriptortype(f)];
-  if (upb_fielddef_isseq(f)) {
-    putop(c, OP_CHECKDELIM, LABEL_ENDMSG);
-    putchecktag(c, f, UPB_WIRE_TYPE_DELIMITED, LABEL_DISPATCH);
-   dispatchtarget(c, method, f, UPB_WIRE_TYPE_DELIMITED);
-    putop(c, OP_PUSHLENDELIM);
-    putop(c, OP_STARTSEQ, getsel(f, UPB_HANDLER_STARTSEQ));  /* Packed */
-   label(c, LABEL_LOOPSTART);
-    putop(c, parse_type, sel);
-    putop(c, OP_CHECKDELIM, LABEL_LOOPBREAK);
-    putop(c, OP_BRANCH, -LABEL_LOOPSTART);
-   dispatchtarget(c, method, f, wire_type);
-    putop(c, OP_PUSHTAGDELIM, 0);
-    putop(c, OP_STARTSEQ, getsel(f, UPB_HANDLER_STARTSEQ));  /* Non-packed */
-   label(c, LABEL_LOOPSTART);
-    putop(c, parse_type, sel);
-    putop(c, OP_CHECKDELIM, LABEL_LOOPBREAK);
-    putchecktag(c, f, wire_type, LABEL_LOOPBREAK);
-    putop(c, OP_BRANCH, -LABEL_LOOPSTART);
-   label(c, LABEL_LOOPBREAK);
-    putop(c, OP_POP);  /* Packed and non-packed join. */
-    maybeput(c, OP_ENDSEQ, h, f, UPB_HANDLER_ENDSEQ);
-    putop(c, OP_SETDELIM);  /* Could remove for non-packed by dup ENDSEQ. */
-  } else {
-    putop(c, OP_CHECKDELIM, LABEL_ENDMSG);
-    putchecktag(c, f, wire_type, LABEL_DISPATCH);
-   dispatchtarget(c, method, f, wire_type);
-    putop(c, parse_type, sel);
-  }
-}
-
-/* Adds bytecode for parsing the given message to the given decoderplan,
- * while adding all dispatch targets to this message's dispatch table. */
-static void compile_method(compiler *c, upb_pbdecodermethod *method) {
-  const upb_handlers *h;
-  const upb_msgdef *md;
-  uint32_t* start_pc;
-  upb_msg_field_iter i;
-  upb_value val;
-
-  assert(method);
-
-  /* Clear all entries in the dispatch table. */
-  upb_inttable_uninit(&method->dispatch);
-  upb_inttable_init(&method->dispatch, UPB_CTYPE_UINT64);
-
-  h = upb_pbdecodermethod_desthandlers(method);
-  md = upb_handlers_msgdef(h);
-
- method->code_base.ofs = pcofs(c);
-  putop(c, OP_SETDISPATCH, &method->dispatch);
-  putsel(c, OP_STARTMSG, UPB_STARTMSG_SELECTOR, h);
- label(c, LABEL_FIELD);
-  start_pc = c->pc;
-  for(upb_msg_field_begin(&i, md);
-      !upb_msg_field_done(&i);
-      upb_msg_field_next(&i)) {
-    const upb_fielddef *f = upb_msg_iter_field(&i);
-    upb_fieldtype_t type = upb_fielddef_type(f);
-
-    if (type == UPB_TYPE_MESSAGE && !(haslazyhandlers(h, f) && c->lazy)) {
-      generate_msgfield(c, f, method);
-    } else if (type == UPB_TYPE_STRING || type == UPB_TYPE_BYTES ||
-               type == UPB_TYPE_MESSAGE) {
-      generate_delimfield(c, f, method);
-    } else {
-      generate_primitivefield(c, f, method);
-    }
-  }
-
-  /* If there were no fields, or if no handlers were defined, we need to
-   * generate a non-empty loop body so that we can at least dispatch for unknown
-   * fields and check for the end of the message. */
-  if (c->pc == start_pc) {
-    /* Check for end-of-message. */
-    putop(c, OP_CHECKDELIM, LABEL_ENDMSG);
-    /* Unconditionally dispatch. */
-    putop(c, OP_DISPATCH, 0);
-  }
-
-  /* For now we just loop back to the last field of the message (or if none,
-   * the DISPATCH opcode for the message). */
-  putop(c, OP_BRANCH, -LABEL_FIELD);
-
-  /* Insert both a label and a dispatch table entry for this end-of-msg. */
- label(c, LABEL_ENDMSG);
-  val = upb_value_uint64(pcofs(c) - method->code_base.ofs);
-  upb_inttable_insert(&method->dispatch, DISPATCH_ENDMSG, val);
-
-  putsel(c, OP_ENDMSG, UPB_ENDMSG_SELECTOR, h);
-  putop(c, OP_RET);
-
-  upb_inttable_compact(&method->dispatch);
-}
-
-/* Populate "methods" with new upb_pbdecodermethod objects reachable from "h".
- * Returns the method for these handlers.
- *
- * Generates a new method for every destination handlers reachable from "h". */
-static void find_methods(compiler *c, const upb_handlers *h) {
-  upb_value v;
-  upb_msg_field_iter i;
-  const upb_msgdef *md;
-
-  if (upb_inttable_lookupptr(&c->group->methods, h, &v))
-    return;
-  newmethod(h, c->group);
-
-  /* Find submethods. */
-  md = upb_handlers_msgdef(h);
-  for(upb_msg_field_begin(&i, md);
-      !upb_msg_field_done(&i);
-      upb_msg_field_next(&i)) {
-    const upb_fielddef *f = upb_msg_iter_field(&i);
-    const upb_handlers *sub_h;
-    if (upb_fielddef_type(f) == UPB_TYPE_MESSAGE &&
-        (sub_h = upb_handlers_getsubhandlers(h, f)) != NULL) {
-      /* We only generate a decoder method for submessages with handlers.
-       * Others will be parsed as unknown fields. */
-      find_methods(c, sub_h);
-    }
-  }
-}
-
-/* (Re-)compile bytecode for all messages in "msgs."
- * Overwrites any existing bytecode in "c". */
-static void compile_methods(compiler *c) {
-  upb_inttable_iter i;
-
-  /* Start over at the beginning of the bytecode. */
-  c->pc = c->group->bytecode;
-
-  upb_inttable_begin(&i, &c->group->methods);
-  for(; !upb_inttable_done(&i); upb_inttable_next(&i)) {
-    upb_pbdecodermethod *method = upb_value_getptr(upb_inttable_iter_value(&i));
-    compile_method(c, method);
-  }
-}
-
-static void set_bytecode_handlers(mgroup *g) {
-  upb_inttable_iter i;
-  upb_inttable_begin(&i, &g->methods);
-  for(; !upb_inttable_done(&i); upb_inttable_next(&i)) {
-    upb_pbdecodermethod *m = upb_value_getptr(upb_inttable_iter_value(&i));
-    upb_byteshandler *h = &m->input_handler_;
-
-    m->code_base.ptr = g->bytecode + m->code_base.ofs;
-
-    upb_byteshandler_setstartstr(h, upb_pbdecoder_startbc, m->code_base.ptr);
-    upb_byteshandler_setstring(h, upb_pbdecoder_decode, g);
-    upb_byteshandler_setendstr(h, upb_pbdecoder_end, m);
-  }
-}
-
-
-/* JIT setup. *****************************************************************/
-
-#ifdef UPB_USE_JIT_X64
-
-static void sethandlers(mgroup *g, bool allowjit) {
-  g->jit_code = NULL;
-  if (allowjit) {
-    /* Compile byte-code into machine code, create handlers. */
-    upb_pbdecoder_jit(g);
-  } else {
-    set_bytecode_handlers(g);
-  }
-}
-
-#else  /* UPB_USE_JIT_X64 */
-
-static void sethandlers(mgroup *g, bool allowjit) {
-  /* No JIT compiled in; use bytecode handlers unconditionally. */
-  UPB_UNUSED(allowjit);
-  set_bytecode_handlers(g);
-}
-
-#endif  /* UPB_USE_JIT_X64 */
-
-
-/* TODO(haberman): allow this to be constructed for an arbitrary set of dest
- * handlers and other mgroups (but verify we have a transitive closure). */
-const mgroup *mgroup_new(const upb_handlers *dest, bool allowjit, bool lazy,
-                         const void *owner) {
-  mgroup *g;
-  compiler *c;
-
-  UPB_UNUSED(allowjit);
-  assert(upb_handlers_isfrozen(dest));
-
-  g = newgroup(owner);
-  c = newcompiler(g, lazy);
-  find_methods(c, dest);
-
-  /* We compile in two passes:
-   * 1. all messages are assigned relative offsets from the beginning of the
-   *    bytecode (saved in method->code_base).
-   * 2. forwards OP_CALL instructions can be correctly linked since message
-   *    offsets have been previously assigned.
-   *
-   * Could avoid the second pass by linking OP_CALL instructions somehow. */
-  compile_methods(c);
-  compile_methods(c);
-  g->bytecode_end = c->pc;
-  freecompiler(c);
-
-#ifdef UPB_DUMP_BYTECODE
-  {
-    FILE *f = fopen("/tmp/upb-bytecode", "wb");
-    assert(f);
-    dumpbc(g->bytecode, g->bytecode_end, stderr);
-    dumpbc(g->bytecode, g->bytecode_end, f);
-    fclose(f);
-  }
-#endif
-
-  sethandlers(g, allowjit);
-  return g;
-}
-
-
-/* upb_pbcodecache ************************************************************/
-
-void upb_pbcodecache_init(upb_pbcodecache *c) {
-  upb_inttable_init(&c->groups, UPB_CTYPE_CONSTPTR);
-  c->allow_jit_ = true;
-}
-
-void upb_pbcodecache_uninit(upb_pbcodecache *c) {
-  upb_inttable_iter i;
-  upb_inttable_begin(&i, &c->groups);
-  for(; !upb_inttable_done(&i); upb_inttable_next(&i)) {
-    const mgroup *group = upb_value_getconstptr(upb_inttable_iter_value(&i));
-    mgroup_unref(group, c);
-  }
-  upb_inttable_uninit(&c->groups);
-}
-
-bool upb_pbcodecache_allowjit(const upb_pbcodecache *c) {
-  return c->allow_jit_;
-}
-
-bool upb_pbcodecache_setallowjit(upb_pbcodecache *c, bool allow) {
-  if (upb_inttable_count(&c->groups) > 0)
-    return false;
-  c->allow_jit_ = allow;
-  return true;
-}
-
-const upb_pbdecodermethod *upb_pbcodecache_getdecodermethod(
-    upb_pbcodecache *c, const upb_pbdecodermethodopts *opts) {
-  upb_value v;
-  bool ok;
-
-  /* Right now we build a new DecoderMethod every time.
-   * TODO(haberman): properly cache methods by their true key. */
-  const mgroup *g = mgroup_new(opts->handlers, c->allow_jit_, opts->lazy, c);
-  upb_inttable_push(&c->groups, upb_value_constptr(g));
-
-  ok = upb_inttable_lookupptr(&g->methods, opts->handlers, &v);
-  UPB_ASSERT_VAR(ok, ok);
-  return upb_value_getptr(v);
-}
-
-
-/* upb_pbdecodermethodopts ****************************************************/
-
-void upb_pbdecodermethodopts_init(upb_pbdecodermethodopts *opts,
-                                  const upb_handlers *h) {
-  opts->handlers = h;
-  opts->lazy = false;
-}
-
-void upb_pbdecodermethodopts_setlazy(upb_pbdecodermethodopts *opts, bool lazy) {
-  opts->lazy = lazy;
-}
-/*
-** upb::Decoder (Bytecode Decoder VM)
-**
-** Bytecode must previously have been generated using the bytecode compiler in
-** compile_decoder.c.  This decoder then walks through the bytecode op-by-op to
-** parse the input.
-**
-** Decoding is fully resumable; we just keep a pointer to the current bytecode
-** instruction and resume from there.  A fair amount of the logic here is to
-** handle the fact that values can span buffer seams and we have to be able to
-** be capable of suspending/resuming from any byte in the stream.  This
-** sometimes requires keeping a few trailing bytes from the last buffer around
-** in the "residual" buffer.
-*/
-
-#include <inttypes.h>
-#include <stddef.h>
-
-#ifdef UPB_DUMP_BYTECODE
-#include <stdio.h>
-#endif
-
-#define CHECK_SUSPEND(x) if (!(x)) return upb_pbdecoder_suspend(d);
-
-/* Error messages that are shared between the bytecode and JIT decoders. */
-const char *kPbDecoderStackOverflow = "Nesting too deep.";
-
-/* Error messages shared within this file. */
-static const char *kUnterminatedVarint = "Unterminated varint.";
-
-/* upb_pbdecoder **************************************************************/
-
-static opcode halt = OP_HALT;
-
-/* Whether an op consumes any of the input buffer. */
-static bool consumes_input(opcode op) {
-  switch (op) {
-    case OP_SETDISPATCH:
-    case OP_STARTMSG:
-    case OP_ENDMSG:
-    case OP_STARTSEQ:
-    case OP_ENDSEQ:
-    case OP_STARTSUBMSG:
-    case OP_ENDSUBMSG:
-    case OP_STARTSTR:
-    case OP_ENDSTR:
-    case OP_PUSHTAGDELIM:
-    case OP_POP:
-    case OP_SETDELIM:
-    case OP_SETBIGGROUPNUM:
-    case OP_CHECKDELIM:
-    case OP_CALL:
-    case OP_RET:
-    case OP_BRANCH:
-      return false;
-    default:
-      return true;
-  }
-}
-
-static bool in_residual_buf(const upb_pbdecoder *d, const char *p);
-
-/* It's unfortunate that we have to micro-manage the compiler with
- * UPB_FORCEINLINE and UPB_NOINLINE, especially since this tuning is necessarily
- * specific to one hardware configuration.  But empirically on a Core i7,
- * performance increases 30-50% with these annotations.  Every instance where
- * these appear, gcc 4.2.1 made the wrong decision and degraded performance in
- * benchmarks. */
-
-static void seterr(upb_pbdecoder *d, const char *msg) {
-  upb_status status = UPB_STATUS_INIT;
-  upb_status_seterrmsg(&status, msg);
-  upb_env_reporterror(d->env, &status);
-}
-
-void upb_pbdecoder_seterr(upb_pbdecoder *d, const char *msg) {
-  seterr(d, msg);
-}
-
-
-/* Buffering ******************************************************************/
-
-/* We operate on one buffer at a time, which is either the user's buffer passed
- * to our "decode" callback or some residual bytes from the previous buffer. */
-
-/* How many bytes can be safely read from d->ptr without reading past end-of-buf
- * or past the current delimited end. */
-static size_t curbufleft(const upb_pbdecoder *d) {
-  assert(d->data_end >= d->ptr);
-  return d->data_end - d->ptr;
-}
-
-/* Overall stream offset of d->ptr. */
-uint64_t offset(const upb_pbdecoder *d) {
-  return d->bufstart_ofs + (d->ptr - d->buf);
-}
-
-/* Advances d->ptr. */
-static void advance(upb_pbdecoder *d, size_t len) {
-  assert(curbufleft(d) >= len);
-  d->ptr += len;
-}
-
-static bool in_buf(const char *p, const char *buf, const char *end) {
-  return p >= buf && p <= end;
-}
-
-static bool in_residual_buf(const upb_pbdecoder *d, const char *p) {
-  return in_buf(p, d->residual, d->residual_end);
-}
-
-/* Calculates the delim_end value, which is affected by both the current buffer
- * and the parsing stack, so must be called whenever either is updated. */
-static void set_delim_end(upb_pbdecoder *d) {
-  size_t delim_ofs = d->top->end_ofs - d->bufstart_ofs;
-  if (delim_ofs <= (size_t)(d->end - d->buf)) {
-    d->delim_end = d->buf + delim_ofs;
-    d->data_end = d->delim_end;
-  } else {
-    d->data_end = d->end;
-    d->delim_end = NULL;
-  }
-}
-
-static void switchtobuf(upb_pbdecoder *d, const char *buf, const char *end) {
-  d->ptr = buf;
-  d->buf = buf;
-  d->end = end;
-  set_delim_end(d);
-}
-
-static void advancetobuf(upb_pbdecoder *d, const char *buf, size_t len) {
-  assert(curbufleft(d) == 0);
-  d->bufstart_ofs += (d->end - d->buf);
-  switchtobuf(d, buf, buf + len);
-}
-
-static void checkpoint(upb_pbdecoder *d) {
-  /* The assertion here is in the interests of efficiency, not correctness.
-   * We are trying to ensure that we don't checkpoint() more often than
-   * necessary. */
-  assert(d->checkpoint != d->ptr);
-  d->checkpoint = d->ptr;
-}
-
-/* Resumes the decoder from an initial state or from a previous suspend. */
-int32_t upb_pbdecoder_resume(upb_pbdecoder *d, void *p, const char *buf,
-                             size_t size, const upb_bufhandle *handle) {
-  UPB_UNUSED(p);  /* Useless; just for the benefit of the JIT. */
-  d->buf_param = buf;
-  d->size_param = size;
-  d->handle = handle;
-  if (d->residual_end > d->residual) {
-    /* We have residual bytes from the last buffer. */
-    assert(d->ptr == d->residual);
-  } else {
-    switchtobuf(d, buf, buf + size);
-  }
-  d->checkpoint = d->ptr;
-  if (d->top->groupnum < 0) {
-    CHECK_RETURN(upb_pbdecoder_skipunknown(d, -1, 0));
-    d->checkpoint = d->ptr;
-  }
-  return DECODE_OK;
-}
-
-/* Suspends the decoder at the last checkpoint, without saving any residual
- * bytes.  If there are any unconsumed bytes, returns a short byte count. */
-size_t upb_pbdecoder_suspend(upb_pbdecoder *d) {
-  d->pc = d->last;
-  if (d->checkpoint == d->residual) {
-    /* Checkpoint was in residual buf; no user bytes were consumed. */
-    d->ptr = d->residual;
-    return 0;
-  } else {
-    size_t consumed;
-    assert(!in_residual_buf(d, d->checkpoint));
-    assert(d->buf == d->buf_param);
-
-    consumed = d->checkpoint - d->buf;
-    d->bufstart_ofs += consumed;
-    d->residual_end = d->residual;
-    switchtobuf(d, d->residual, d->residual_end);
-    return consumed;
-  }
-}
-
-/* Suspends the decoder at the last checkpoint, and saves any unconsumed
- * bytes in our residual buffer.  This is necessary if we need more user
- * bytes to form a complete value, which might not be contiguous in the
- * user's buffers.  Always consumes all user bytes. */
-static size_t suspend_save(upb_pbdecoder *d) {
-  /* We hit end-of-buffer before we could parse a full value.
-   * Save any unconsumed bytes (if any) to the residual buffer. */
-  d->pc = d->last;
-
-  if (d->checkpoint == d->residual) {
-    /* Checkpoint was in residual buf; append user byte(s) to residual buf. */
-    assert((d->residual_end - d->residual) + d->size_param <=
-           sizeof(d->residual));
-    if (!in_residual_buf(d, d->ptr)) {
-      d->bufstart_ofs -= (d->residual_end - d->residual);
-    }
-    memcpy(d->residual_end, d->buf_param, d->size_param);
-    d->residual_end += d->size_param;
-  } else {
-    /* Checkpoint was in user buf; old residual bytes not needed. */
-    size_t save;
-    assert(!in_residual_buf(d, d->checkpoint));
-
-    d->ptr = d->checkpoint;
-    save = curbufleft(d);
-    assert(save <= sizeof(d->residual));
-    memcpy(d->residual, d->ptr, save);
-    d->residual_end = d->residual + save;
-    d->bufstart_ofs = offset(d);
-  }
-
-  switchtobuf(d, d->residual, d->residual_end);
-  return d->size_param;
-}
-
-/* Skips "bytes" bytes in the stream, which may be more than available.  If we
- * skip more bytes than are available, we return a long read count to the caller
- * indicating how many bytes the caller should skip before passing a new buffer.
- */
-static int32_t skip(upb_pbdecoder *d, size_t bytes) {
-  assert(!in_residual_buf(d, d->ptr) || d->size_param == 0);
-  if (curbufleft(d) >= bytes) {
-    /* Skipped data is all in current buffer. */
-    advance(d, bytes);
-    return DECODE_OK;
-  } else {
-    /* Skipped data extends beyond currently available buffers. */
-    size_t skip;
-    d->pc = d->last;
-    skip = bytes - curbufleft(d);
-    d->bufstart_ofs += (d->end - d->buf) + skip;
-    d->residual_end = d->residual;
-    switchtobuf(d, d->residual, d->residual_end);
-    return d->size_param + skip;
-  }
-}
-
-/* Copies the next "bytes" bytes into "buf" and advances the stream.
- * Requires that this many bytes are available in the current buffer. */
-UPB_FORCEINLINE static void consumebytes(upb_pbdecoder *d, void *buf,
-                                         size_t bytes) {
-  assert(bytes <= curbufleft(d));
-  memcpy(buf, d->ptr, bytes);
-  advance(d, bytes);
-}
-
-/* Slow path for getting the next "bytes" bytes, regardless of whether they are
- * available in the current buffer or not.  Returns a status code as described
- * in decoder.int.h. */
-UPB_NOINLINE static int32_t getbytes_slow(upb_pbdecoder *d, void *buf,
-                                          size_t bytes) {
-  const size_t avail = curbufleft(d);
-  consumebytes(d, buf, avail);
-  bytes -= avail;
-  assert(bytes > 0);
-  if (in_residual_buf(d, d->ptr)) {
-    advancetobuf(d, d->buf_param, d->size_param);
-  }
-  if (curbufleft(d) >= bytes) {
-    consumebytes(d, (char *)buf + avail, bytes);
-    return DECODE_OK;
-  } else if (d->data_end == d->delim_end) {
-    seterr(d, "Submessage ended in the middle of a value or group");
-    return upb_pbdecoder_suspend(d);
-  } else {
-    return suspend_save(d);
-  }
-}
-
-/* Gets the next "bytes" bytes, regardless of whether they are available in the
- * current buffer or not.  Returns a status code as described in decoder.int.h.
- */
-UPB_FORCEINLINE static int32_t getbytes(upb_pbdecoder *d, void *buf,
-                                        size_t bytes) {
-  if (curbufleft(d) >= bytes) {
-    /* Buffer has enough data to satisfy. */
-    consumebytes(d, buf, bytes);
-    return DECODE_OK;
-  } else {
-    return getbytes_slow(d, buf, bytes);
-  }
-}
-
-UPB_NOINLINE static size_t peekbytes_slow(upb_pbdecoder *d, void *buf,
-                                          size_t bytes) {
-  size_t ret = curbufleft(d);
-  memcpy(buf, d->ptr, ret);
-  if (in_residual_buf(d, d->ptr)) {
-    size_t copy = UPB_MIN(bytes - ret, d->size_param);
-    memcpy((char *)buf + ret, d->buf_param, copy);
-    ret += copy;
-  }
-  return ret;
-}
-
-UPB_FORCEINLINE static size_t peekbytes(upb_pbdecoder *d, void *buf,
-                                        size_t bytes) {
-  if (curbufleft(d) >= bytes) {
-    memcpy(buf, d->ptr, bytes);
-    return bytes;
-  } else {
-    return peekbytes_slow(d, buf, bytes);
-  }
-}
-
-
-/* Decoding of wire types *****************************************************/
-
-/* Slow path for decoding a varint from the current buffer position.
- * Returns a status code as described in decoder.int.h. */
-UPB_NOINLINE int32_t upb_pbdecoder_decode_varint_slow(upb_pbdecoder *d,
-                                                      uint64_t *u64) {
-  uint8_t byte = 0x80;
-  int bitpos;
-  *u64 = 0;
-  for(bitpos = 0; bitpos < 70 && (byte & 0x80); bitpos += 7) {
-    int32_t ret = getbytes(d, &byte, 1);
-    if (ret >= 0) return ret;
-    *u64 |= (uint64_t)(byte & 0x7F) << bitpos;
-  }
-  if(bitpos == 70 && (byte & 0x80)) {
-    seterr(d, kUnterminatedVarint);
-    return upb_pbdecoder_suspend(d);
-  }
-  return DECODE_OK;
-}
-
-/* Decodes a varint from the current buffer position.
- * Returns a status code as described in decoder.int.h. */
-UPB_FORCEINLINE static int32_t decode_varint(upb_pbdecoder *d, uint64_t *u64) {
-  if (curbufleft(d) > 0 && !(*d->ptr & 0x80)) {
-    *u64 = *d->ptr;
-    advance(d, 1);
-    return DECODE_OK;
-  } else if (curbufleft(d) >= 10) {
-    /* Fast case. */
-    upb_decoderet r = upb_vdecode_fast(d->ptr);
-    if (r.p == NULL) {
-      seterr(d, kUnterminatedVarint);
-      return upb_pbdecoder_suspend(d);
-    }
-    advance(d, r.p - d->ptr);
-    *u64 = r.val;
-    return DECODE_OK;
-  } else {
-    /* Slow case -- varint spans buffer seam. */
-    return upb_pbdecoder_decode_varint_slow(d, u64);
-  }
-}
-
-/* Decodes a 32-bit varint from the current buffer position.
- * Returns a status code as described in decoder.int.h. */
-UPB_FORCEINLINE static int32_t decode_v32(upb_pbdecoder *d, uint32_t *u32) {
-  uint64_t u64;
-  int32_t ret = decode_varint(d, &u64);
-  if (ret >= 0) return ret;
-  if (u64 > UINT32_MAX) {
-    seterr(d, "Unterminated 32-bit varint");
-    /* TODO(haberman) guarantee that this function return is >= 0 somehow,
-     * so we know this path will always be treated as error by our caller.
-     * Right now the size_t -> int32_t can overflow and produce negative values.
-     */
-    *u32 = 0;
-    return upb_pbdecoder_suspend(d);
-  }
-  *u32 = u64;
-  return DECODE_OK;
-}
-
-/* Decodes a fixed32 from the current buffer position.
- * Returns a status code as described in decoder.int.h.
- * TODO: proper byte swapping for big-endian machines. */
-UPB_FORCEINLINE static int32_t decode_fixed32(upb_pbdecoder *d, uint32_t *u32) {
-  return getbytes(d, u32, 4);
-}
-
-/* Decodes a fixed64 from the current buffer position.
- * Returns a status code as described in decoder.int.h.
- * TODO: proper byte swapping for big-endian machines. */
-UPB_FORCEINLINE static int32_t decode_fixed64(upb_pbdecoder *d, uint64_t *u64) {
-  return getbytes(d, u64, 8);
-}
-
-/* Non-static versions of the above functions.
- * These are called by the JIT for fallback paths. */
-int32_t upb_pbdecoder_decode_f32(upb_pbdecoder *d, uint32_t *u32) {
-  return decode_fixed32(d, u32);
-}
-
-int32_t upb_pbdecoder_decode_f64(upb_pbdecoder *d, uint64_t *u64) {
-  return decode_fixed64(d, u64);
-}
-
-static double as_double(uint64_t n) { double d; memcpy(&d, &n, 8); return d; }
-static float  as_float(uint32_t n)  { float  f; memcpy(&f, &n, 4); return f; }
-
-/* Pushes a frame onto the decoder stack. */
-static bool decoder_push(upb_pbdecoder *d, uint64_t end) {
-  upb_pbdecoder_frame *fr = d->top;
-
-  if (end > fr->end_ofs) {
-    seterr(d, "Submessage end extends past enclosing submessage.");
-    return false;
-  } else if (fr == d->limit) {
-    seterr(d, kPbDecoderStackOverflow);
-    return false;
-  }
-
-  fr++;
-  fr->end_ofs = end;
-  fr->dispatch = NULL;
-  fr->groupnum = 0;
-  d->top = fr;
-  return true;
-}
-
-static bool pushtagdelim(upb_pbdecoder *d, uint32_t arg) {
-  /* While we expect to see an "end" tag (either ENDGROUP or a non-sequence
-   * field number) prior to hitting any enclosing submessage end, pushing our
-   * existing delim end prevents us from continuing to parse values from a
-   * corrupt proto that doesn't give us an END tag in time. */
-  if (!decoder_push(d, d->top->end_ofs))
-    return false;
-  d->top->groupnum = arg;
-  return true;
-}
-
-/* Pops a frame from the decoder stack. */
-static void decoder_pop(upb_pbdecoder *d) { d->top--; }
-
-UPB_NOINLINE int32_t upb_pbdecoder_checktag_slow(upb_pbdecoder *d,
-                                                 uint64_t expected) {
-  uint64_t data = 0;
-  size_t bytes = upb_value_size(expected);
-  size_t read = peekbytes(d, &data, bytes);
-  if (read == bytes && data == expected) {
-    /* Advance past matched bytes. */
-    int32_t ok = getbytes(d, &data, read);
-    UPB_ASSERT_VAR(ok, ok < 0);
-    return DECODE_OK;
-  } else if (read < bytes && memcmp(&data, &expected, read) == 0) {
-    return suspend_save(d);
-  } else {
-    return DECODE_MISMATCH;
-  }
-}
-
-int32_t upb_pbdecoder_skipunknown(upb_pbdecoder *d, int32_t fieldnum,
-                                  uint8_t wire_type) {
-  if (fieldnum >= 0)
-    goto have_tag;
-
-  while (true) {
-    uint32_t tag;
-    CHECK_RETURN(decode_v32(d, &tag));
-    wire_type = tag & 0x7;
-    fieldnum = tag >> 3;
-
-have_tag:
-    if (fieldnum == 0) {
-      seterr(d, "Saw invalid field number (0)");
-      return upb_pbdecoder_suspend(d);
-    }
-
-    /* TODO: deliver to unknown field callback. */
-    switch (wire_type) {
-      case UPB_WIRE_TYPE_32BIT:
-        CHECK_RETURN(skip(d, 4));
-        break;
-      case UPB_WIRE_TYPE_64BIT:
-        CHECK_RETURN(skip(d, 8));
-        break;
-      case UPB_WIRE_TYPE_VARINT: {
-        uint64_t u64;
-        CHECK_RETURN(decode_varint(d, &u64));
-        break;
-      }
-      case UPB_WIRE_TYPE_DELIMITED: {
-        uint32_t len;
-        CHECK_RETURN(decode_v32(d, &len));
-        CHECK_RETURN(skip(d, len));
-        break;
-      }
-      case UPB_WIRE_TYPE_START_GROUP:
-        CHECK_SUSPEND(pushtagdelim(d, -fieldnum));
-        break;
-      case UPB_WIRE_TYPE_END_GROUP:
-        if (fieldnum == -d->top->groupnum) {
-          decoder_pop(d);
-        } else if (fieldnum == d->top->groupnum) {
-          return DECODE_ENDGROUP;
-        } else {
-          seterr(d, "Unmatched ENDGROUP tag.");
-          return upb_pbdecoder_suspend(d);
-        }
-        break;
-      default:
-        seterr(d, "Invalid wire type");
-        return upb_pbdecoder_suspend(d);
-    }
-
-    if (d->top->groupnum >= 0) {
-      return DECODE_OK;
-    }
-
-    if (d->ptr == d->delim_end) {
-      seterr(d, "Enclosing submessage ended in the middle of value or group");
-      /* Unlike most errors we notice during parsing, right now we have consumed
-       * all of the user's input.
-       *
-       * There are three different options for how to handle this case:
-       *
-       *   1. decode() = short count, error = set
-       *   2. decode() = full count, error = set
-       *   3. decode() = full count, error NOT set, short count and error will
-       *      be reported on next call to decode() (or end())
-       *
-       * (1) and (3) have the advantage that they preserve the invariant that an
-       * error occurs iff decode() returns a short count.
-       *
-       * (2) and (3) have the advantage of reflecting the fact that all of the
-       * bytes were in fact parsed (and possibly delivered to the unknown field
-       * handler, in the future when that is supported).
-       *
-       * (3) requires extra state in the decode (a place to store the "permanent
-       * error" that we should return for all subsequent attempts to decode).
-       * But we likely want this anyway.
-       *
-       * Right now we do (1), thanks to the fact that we checkpoint *after* this
-       * check.  (3) may be a better choice long term; unclear at the moment. */
-      return upb_pbdecoder_suspend(d);
-    }
-
-    checkpoint(d);
-  }
-}
-
-static void goto_endmsg(upb_pbdecoder *d) {
-  upb_value v;
-  bool found = upb_inttable_lookup32(d->top->dispatch, DISPATCH_ENDMSG, &v);
-  UPB_ASSERT_VAR(found, found);
-  d->pc = d->top->base + upb_value_getuint64(v);
-}
-
-/* Parses a tag and jumps to the corresponding bytecode instruction for this
- * field.
- *
- * If the tag is unknown (or the wire type doesn't match), parses the field as
- * unknown.  If the tag is a valid ENDGROUP tag, jumps to the bytecode
- * instruction for the end of message. */
-static int32_t dispatch(upb_pbdecoder *d) {
-  upb_inttable *dispatch = d->top->dispatch;
-  uint32_t tag;
-  uint8_t wire_type;
-  uint32_t fieldnum;
-  upb_value val;
-  int32_t ret;
-
-  /* Decode tag. */
-  CHECK_RETURN(decode_v32(d, &tag));
-  wire_type = tag & 0x7;
-  fieldnum = tag >> 3;
-
-  /* Lookup tag.  Because of packed/non-packed compatibility, we have to
-   * check the wire type against two possibilities. */
-  if (fieldnum != DISPATCH_ENDMSG &&
-      upb_inttable_lookup32(dispatch, fieldnum, &val)) {
-    uint64_t v = upb_value_getuint64(val);
-    if (wire_type == (v & 0xff)) {
-      d->pc = d->top->base + (v >> 16);
-      return DECODE_OK;
-    } else if (wire_type == ((v >> 8) & 0xff)) {
-      bool found =
-          upb_inttable_lookup(dispatch, fieldnum + UPB_MAX_FIELDNUMBER, &val);
-      UPB_ASSERT_VAR(found, found);
-      d->pc = d->top->base + upb_value_getuint64(val);
-      return DECODE_OK;
-    }
-  }
-
-  /* Unknown field or ENDGROUP. */
-  ret = upb_pbdecoder_skipunknown(d, fieldnum, wire_type);
-
-  if (ret == DECODE_ENDGROUP) {
-    goto_endmsg(d);
-    return DECODE_OK;
-  } else if (ret == DECODE_OK) {
-    /* We just consumed some input, so we might now have consumed all the data
-     * in the delmited region.  Since every opcode that can trigger dispatch is
-     * directly preceded by OP_CHECKDELIM, rewind to it now to re-check the
-     * delimited end. */
-    d->pc = d->last - 1;
-    assert(getop(*d->pc) == OP_CHECKDELIM);
-    return DECODE_OK;
-  }
-
-  return ret;
-}
-
-/* Callers know that the stack is more than one deep because the opcodes that
- * call this only occur after PUSH operations. */
-upb_pbdecoder_frame *outer_frame(upb_pbdecoder *d) {
-  assert(d->top != d->stack);
-  return d->top - 1;
-}
-
-
-/* The main decoding loop *****************************************************/
-
-/* The main decoder VM function.  Uses traditional bytecode dispatch loop with a
- * switch() statement. */
-size_t upb_pbdecoder_decode(void *closure, const void *hd, const char *buf,
-                            size_t size, const upb_bufhandle *handle) {
-  upb_pbdecoder *d = closure;
-  const mgroup *group = hd;
-  int32_t result;
-  assert(buf);
-  result = upb_pbdecoder_resume(d, NULL, buf, size, handle);
-  if (result == DECODE_ENDGROUP) {
-    goto_endmsg(d);
-  }
-  CHECK_RETURN(result);
-  UPB_UNUSED(group);
-
-#define VMCASE(op, code) \
-  case op: { code; if (consumes_input(op)) checkpoint(d); break; }
-#define PRIMITIVE_OP(type, wt, name, convfunc, ctype) \
-  VMCASE(OP_PARSE_ ## type, { \
-    ctype val; \
-    CHECK_RETURN(decode_ ## wt(d, &val)); \
-    upb_sink_put ## name(&d->top->sink, arg, (convfunc)(val)); \
-  })
-
-  while(1) {
-    int32_t instruction;
-    opcode op;
-    uint32_t arg;
-    int32_t longofs;
-
-    d->last = d->pc;
-    instruction = *d->pc++;
-    op = getop(instruction);
-    arg = instruction >> 8;
-    longofs = arg;
-    assert(d->ptr != d->residual_end);
-#ifdef UPB_DUMP_BYTECODE
-    fprintf(stderr, "s_ofs=%d buf_ofs=%d data_rem=%d buf_rem=%d delim_rem=%d "
-                    "%x %s (%d)\n",
-            (int)offset(d),
-            (int)(d->ptr - d->buf),
-            (int)(d->data_end - d->ptr),
-            (int)(d->end - d->ptr),
-            (int)((d->top->end_ofs - d->bufstart_ofs) - (d->ptr - d->buf)),
-            (int)(d->pc - 1 - group->bytecode),
-            upb_pbdecoder_getopname(op),
-            arg);
-#endif
-    switch (op) {
-      /* Technically, we are losing data if we see a 32-bit varint that is not
-       * properly sign-extended.  We could detect this and error about the data
-       * loss, but proto2 does not do this, so we pass. */
-      PRIMITIVE_OP(INT32,    varint,  int32,  int32_t,      uint64_t)
-      PRIMITIVE_OP(INT64,    varint,  int64,  int64_t,      uint64_t)
-      PRIMITIVE_OP(UINT32,   varint,  uint32, uint32_t,     uint64_t)
-      PRIMITIVE_OP(UINT64,   varint,  uint64, uint64_t,     uint64_t)
-      PRIMITIVE_OP(FIXED32,  fixed32, uint32, uint32_t,     uint32_t)
-      PRIMITIVE_OP(FIXED64,  fixed64, uint64, uint64_t,     uint64_t)
-      PRIMITIVE_OP(SFIXED32, fixed32, int32,  int32_t,      uint32_t)
-      PRIMITIVE_OP(SFIXED64, fixed64, int64,  int64_t,      uint64_t)
-      PRIMITIVE_OP(BOOL,     varint,  bool,   bool,         uint64_t)
-      PRIMITIVE_OP(DOUBLE,   fixed64, double, as_double,    uint64_t)
-      PRIMITIVE_OP(FLOAT,    fixed32, float,  as_float,     uint32_t)
-      PRIMITIVE_OP(SINT32,   varint,  int32,  upb_zzdec_32, uint64_t)
-      PRIMITIVE_OP(SINT64,   varint,  int64,  upb_zzdec_64, uint64_t)
-
-      VMCASE(OP_SETDISPATCH,
-        d->top->base = d->pc - 1;
-        memcpy(&d->top->dispatch, d->pc, sizeof(void*));
-        d->pc += sizeof(void*) / sizeof(uint32_t);
-      )
-      VMCASE(OP_STARTMSG,
-        CHECK_SUSPEND(upb_sink_startmsg(&d->top->sink));
-      )
-      VMCASE(OP_ENDMSG,
-        CHECK_SUSPEND(upb_sink_endmsg(&d->top->sink, d->status));
-      )
-      VMCASE(OP_STARTSEQ,
-        upb_pbdecoder_frame *outer = outer_frame(d);
-        CHECK_SUSPEND(upb_sink_startseq(&outer->sink, arg, &d->top->sink));
-      )
-      VMCASE(OP_ENDSEQ,
-        CHECK_SUSPEND(upb_sink_endseq(&d->top->sink, arg));
-      )
-      VMCASE(OP_STARTSUBMSG,
-        upb_pbdecoder_frame *outer = outer_frame(d);
-        CHECK_SUSPEND(upb_sink_startsubmsg(&outer->sink, arg, &d->top->sink));
-      )
-      VMCASE(OP_ENDSUBMSG,
-        CHECK_SUSPEND(upb_sink_endsubmsg(&d->top->sink, arg));
-      )
-      VMCASE(OP_STARTSTR,
-        uint32_t len = d->top->end_ofs - offset(d);
-        upb_pbdecoder_frame *outer = outer_frame(d);
-        CHECK_SUSPEND(upb_sink_startstr(&outer->sink, arg, len, &d->top->sink));
-        if (len == 0) {
-          d->pc++;  /* Skip OP_STRING. */
-        }
-      )
-      VMCASE(OP_STRING,
-        uint32_t len = curbufleft(d);
-        size_t n = upb_sink_putstring(&d->top->sink, arg, d->ptr, len, handle);
-        if (n > len) {
-          if (n > d->top->end_ofs - offset(d)) {
-            seterr(d, "Tried to skip past end of string.");
-            return upb_pbdecoder_suspend(d);
-          } else {
-            int32_t ret = skip(d, n);
-            /* This shouldn't return DECODE_OK, because n > len. */
-            assert(ret >= 0);
-            return ret;
-          }
-        }
-        advance(d, n);
-        if (n < len || d->delim_end == NULL) {
-          /* We aren't finished with this string yet. */
-          d->pc--;  /* Repeat OP_STRING. */
-          if (n > 0) checkpoint(d);
-          return upb_pbdecoder_suspend(d);
-        }
-      )
-      VMCASE(OP_ENDSTR,
-        CHECK_SUSPEND(upb_sink_endstr(&d->top->sink, arg));
-      )
-      VMCASE(OP_PUSHTAGDELIM,
-        CHECK_SUSPEND(pushtagdelim(d, arg));
-      )
-      VMCASE(OP_SETBIGGROUPNUM,
-        d->top->groupnum = *d->pc++;
-      )
-      VMCASE(OP_POP,
-        assert(d->top > d->stack);
-        decoder_pop(d);
-      )
-      VMCASE(OP_PUSHLENDELIM,
-        uint32_t len;
-        CHECK_RETURN(decode_v32(d, &len));
-        CHECK_SUSPEND(decoder_push(d, offset(d) + len));
-        set_delim_end(d);
-      )
-      VMCASE(OP_SETDELIM,
-        set_delim_end(d);
-      )
-      VMCASE(OP_CHECKDELIM,
-        /* We are guaranteed of this assert because we never allow ourselves to
-         * consume bytes beyond data_end, which covers delim_end when non-NULL.
-         */
-        assert(!(d->delim_end && d->ptr > d->delim_end));
-        if (d->ptr == d->delim_end)
-          d->pc += longofs;
-      )
-      VMCASE(OP_CALL,
-        d->callstack[d->call_len++] = d->pc;
-        d->pc += longofs;
-      )
-      VMCASE(OP_RET,
-        assert(d->call_len > 0);
-        d->pc = d->callstack[--d->call_len];
-      )
-      VMCASE(OP_BRANCH,
-        d->pc += longofs;
-      )
-      VMCASE(OP_TAG1,
-        uint8_t expected;
-        CHECK_SUSPEND(curbufleft(d) > 0);
-        expected = (arg >> 8) & 0xff;
-        if (*d->ptr == expected) {
-          advance(d, 1);
-        } else {
-          int8_t shortofs;
-         badtag:
-          shortofs = arg;
-          if (shortofs == LABEL_DISPATCH) {
-            CHECK_RETURN(dispatch(d));
-          } else {
-            d->pc += shortofs;
-            break; /* Avoid checkpoint(). */
-          }
-        }
-      )
-      VMCASE(OP_TAG2,
-        uint16_t expected;
-        CHECK_SUSPEND(curbufleft(d) > 0);
-        expected = (arg >> 8) & 0xffff;
-        if (curbufleft(d) >= 2) {
-          uint16_t actual;
-          memcpy(&actual, d->ptr, 2);
-          if (expected == actual) {
-            advance(d, 2);
-          } else {
-            goto badtag;
-          }
-        } else {
-          int32_t result = upb_pbdecoder_checktag_slow(d, expected);
-          if (result == DECODE_MISMATCH) goto badtag;
-          if (result >= 0) return result;
-        }
-      )
-      VMCASE(OP_TAGN, {
-        uint64_t expected;
-        int32_t result;
-        memcpy(&expected, d->pc, 8);
-        d->pc += 2;
-        result = upb_pbdecoder_checktag_slow(d, expected);
-        if (result == DECODE_MISMATCH) goto badtag;
-        if (result >= 0) return result;
-      })
-      VMCASE(OP_DISPATCH, {
-        CHECK_RETURN(dispatch(d));
-      })
-      VMCASE(OP_HALT, {
-        return size;
-      })
-    }
-  }
-}
-
-void *upb_pbdecoder_startbc(void *closure, const void *pc, size_t size_hint) {
-  upb_pbdecoder *d = closure;
-  UPB_UNUSED(size_hint);
-  d->top->end_ofs = UINT64_MAX;
-  d->bufstart_ofs = 0;
-  d->call_len = 1;
-  d->callstack[0] = &halt;
-  d->pc = pc;
-  return d;
-}
-
-void *upb_pbdecoder_startjit(void *closure, const void *hd, size_t size_hint) {
-  upb_pbdecoder *d = closure;
-  UPB_UNUSED(hd);
-  UPB_UNUSED(size_hint);
-  d->top->end_ofs = UINT64_MAX;
-  d->bufstart_ofs = 0;
-  d->call_len = 0;
-  return d;
-}
-
-bool upb_pbdecoder_end(void *closure, const void *handler_data) {
-  upb_pbdecoder *d = closure;
-  const upb_pbdecodermethod *method = handler_data;
-  uint64_t end;
-  char dummy;
-#ifdef UPB_USE_JIT_X64
-  const mgroup *group = (const mgroup*)method->group;
-#endif
-
-  if (d->residual_end > d->residual) {
-    seterr(d, "Unexpected EOF");
-    return false;
-  }
-
-  if (d->top->end_ofs != UINT64_MAX) {
-    seterr(d, "Unexpected EOF inside delimited string");
-    return false;
-  }
-
-  /* Message ends here. */
-  end = offset(d);
-  d->top->end_ofs = end;
-
-#ifdef UPB_USE_JIT_X64
-  if (group->jit_code) {
-    if (d->top != d->stack)
-      d->stack->end_ofs = 0;
-    group->jit_code(closure, method->code_base.ptr, &dummy, 0, NULL);
-  } else
-#endif
-  {
-    const uint32_t *p = d->pc;
-    d->stack->end_ofs = end;
-    /* Check the previous bytecode, but guard against beginning. */
-    if (p != method->code_base.ptr) p--;
-    if (getop(*p) == OP_CHECKDELIM) {
-      /* Rewind from OP_TAG* to OP_CHECKDELIM. */
-      assert(getop(*d->pc) == OP_TAG1 ||
-             getop(*d->pc) == OP_TAG2 ||
-             getop(*d->pc) == OP_TAGN ||
-             getop(*d->pc) == OP_DISPATCH);
-      d->pc = p;
-    }
-    upb_pbdecoder_decode(closure, handler_data, &dummy, 0, NULL);
-  }
-
-  if (d->call_len != 0) {
-    seterr(d, "Unexpected EOF");
-    return false;
-  }
-
-  return true;
-}
-
-void upb_pbdecoder_reset(upb_pbdecoder *d) {
-  d->top = d->stack;
-  d->top->groupnum = 0;
-  d->ptr = d->residual;
-  d->buf = d->residual;
-  d->end = d->residual;
-  d->residual_end = d->residual;
-}
-
-static size_t stacksize(upb_pbdecoder *d, size_t entries) {
-  UPB_UNUSED(d);
-  return entries * sizeof(upb_pbdecoder_frame);
-}
-
-static size_t callstacksize(upb_pbdecoder *d, size_t entries) {
-  UPB_UNUSED(d);
-
-#ifdef UPB_USE_JIT_X64
-  if (d->method_->is_native_) {
-    /* Each native stack frame needs two pointers, plus we need a few frames for
-     * the enter/exit trampolines. */
-    size_t ret = entries * sizeof(void*) * 2;
-    ret += sizeof(void*) * 10;
-    return ret;
-  }
-#endif
-
-  return entries * sizeof(uint32_t*);
-}
-
-upb_pbdecoder *upb_pbdecoder_create(upb_env *e, const upb_pbdecodermethod *m,
-                                    upb_sink *sink) {
-  const size_t default_max_nesting = 64;
-#ifndef NDEBUG
-  size_t size_before = upb_env_bytesallocated(e);
-#endif
-
-  upb_pbdecoder *d = upb_env_malloc(e, sizeof(upb_pbdecoder));
-  if (!d) return NULL;
-
-  d->method_ = m;
-  d->callstack = upb_env_malloc(e, callstacksize(d, default_max_nesting));
-  d->stack = upb_env_malloc(e, stacksize(d, default_max_nesting));
-  if (!d->stack || !d->callstack) {
-    return NULL;
-  }
-
-  d->env = e;
-  d->limit = d->stack + default_max_nesting - 1;
-  d->stack_size = default_max_nesting;
-
-  upb_pbdecoder_reset(d);
-  upb_bytessink_reset(&d->input_, &m->input_handler_, d);
-
-  assert(sink);
-  if (d->method_->dest_handlers_) {
-    if (sink->handlers != d->method_->dest_handlers_)
-      return NULL;
-  }
-  upb_sink_reset(&d->top->sink, sink->handlers, sink->closure);
-
-  /* If this fails, increase the value in decoder.h. */
-  assert(upb_env_bytesallocated(e) - size_before <= UPB_PB_DECODER_SIZE);
-  return d;
-}
-
-uint64_t upb_pbdecoder_bytesparsed(const upb_pbdecoder *d) {
-  return offset(d);
-}
-
-const upb_pbdecodermethod *upb_pbdecoder_method(const upb_pbdecoder *d) {
-  return d->method_;
-}
-
-upb_bytessink *upb_pbdecoder_input(upb_pbdecoder *d) {
-  return &d->input_;
-}
-
-size_t upb_pbdecoder_maxnesting(const upb_pbdecoder *d) {
-  return d->stack_size;
-}
-
-bool upb_pbdecoder_setmaxnesting(upb_pbdecoder *d, size_t max) {
-  assert(d->top >= d->stack);
-
-  if (max < (size_t)(d->top - d->stack)) {
-    /* Can't set a limit smaller than what we are currently at. */
-    return false;
-  }
-
-  if (max > d->stack_size) {
-    /* Need to reallocate stack and callstack to accommodate. */
-    size_t old_size = stacksize(d, d->stack_size);
-    size_t new_size = stacksize(d, max);
-    void *p = upb_env_realloc(d->env, d->stack, old_size, new_size);
-    if (!p) {
-      return false;
-    }
-    d->stack = p;
-
-    old_size = callstacksize(d, d->stack_size);
-    new_size = callstacksize(d, max);
-    p = upb_env_realloc(d->env, d->callstack, old_size, new_size);
-    if (!p) {
-      return false;
-    }
-    d->callstack = p;
-
-    d->stack_size = max;
-  }
-
-  d->limit = d->stack + max - 1;
-  return true;
-}
-/*
-** upb::Encoder
-**
-** Since we are implementing pure handlers (ie. without any out-of-band access
-** to pre-computed lengths), we have to buffer all submessages before we can
-** emit even their first byte.
-**
-** Not knowing the size of submessages also means we can't write a perfect
-** zero-copy implementation, even with buffering.  Lengths are stored as
-** varints, which means that we don't know how many bytes to reserve for the
-** length until we know what the length is.
-**
-** This leaves us with three main choices:
-**
-** 1. buffer all submessage data in a temporary buffer, then copy it exactly
-**    once into the output buffer.
-**
-** 2. attempt to buffer data directly into the output buffer, estimating how
-**    many bytes each length will take.  When our guesses are wrong, use
-**    memmove() to grow or shrink the allotted space.
-**
-** 3. buffer directly into the output buffer, allocating a max length
-**    ahead-of-time for each submessage length.  If we overallocated, we waste
-**    space, but no memcpy() or memmove() is required.  This approach requires
-**    defining a maximum size for submessages and rejecting submessages that
-**    exceed that size.
-**
-** (2) and (3) have the potential to have better performance, but they are more
-** complicated and subtle to implement:
-**
-**   (3) requires making an arbitrary choice of the maximum message size; it
-**       wastes space when submessages are shorter than this and fails
-**       completely when they are longer.  This makes it more finicky and
-**       requires configuration based on the input.  It also makes it impossible
-**       to perfectly match the output of reference encoders that always use the
-**       optimal amount of space for each length.
-**
-**   (2) requires guessing the the size upfront, and if multiple lengths are
-**       guessed wrong the minimum required number of memmove() operations may
-**       be complicated to compute correctly.  Implemented properly, it may have
-**       a useful amortized or average cost, but more investigation is required
-**       to determine this and what the optimal algorithm is to achieve it.
-**
-**   (1) makes you always pay for exactly one copy, but its implementation is
-**       the simplest and its performance is predictable.
-**
-** So for now, we implement (1) only.  If we wish to optimize later, we should
-** be able to do it without affecting users.
-**
-** The strategy is to buffer the segments of data that do *not* depend on
-** unknown lengths in one buffer, and keep a separate buffer of segment pointers
-** and lengths.  When the top-level submessage ends, we can go beginning to end,
-** alternating the writing of lengths with memcpy() of the rest of the data.
-** At the top level though, no buffering is required.
-*/
-
-
-#include <stdlib.h>
-
-/* The output buffer is divided into segments; a segment is a string of data
- * that is "ready to go" -- it does not need any varint lengths inserted into
- * the middle.  The seams between segments are where varints will be inserted
- * once they are known.
- *
- * We also use the concept of a "run", which is a range of encoded bytes that
- * occur at a single submessage level.  Every segment contains one or more runs.
- *
- * A segment can span messages.  Consider:
- *
- *                  .--Submessage lengths---------.
- *                  |       |                     |
- *                  |       V                     V
- *                  V      | |---------------    | |-----------------
- * Submessages:    | |-----------------------------------------------
- * Top-level msg: ------------------------------------------------------------
- *
- * Segments:          -----   -------------------   -----------------
- * Runs:              *----   *--------------*---   *----------------
- * (* marks the start)
- *
- * Note that the top-level menssage is not in any segment because it does not
- * have any length preceding it.
- *
- * A segment is only interrupted when another length needs to be inserted.  So
- * observe how the second segment spans both the inner submessage and part of
- * the next enclosing message. */
-typedef struct {
-  uint32_t msglen;  /* The length to varint-encode before this segment. */
-  uint32_t seglen;  /* Length of the segment. */
-} upb_pb_encoder_segment;
-
-struct upb_pb_encoder {
-  upb_env *env;
-
-  /* Our input and output. */
-  upb_sink input_;
-  upb_bytessink *output_;
-
-  /* The "subclosure" -- used as the inner closure as part of the bytessink
-   * protocol. */
-  void *subc;
-
-  /* The output buffer and limit, and our current write position.  "buf"
-   * initially points to "initbuf", but is dynamically allocated if we need to
-   * grow beyond the initial size. */
-  char *buf, *ptr, *limit;
-
-  /* The beginning of the current run, or undefined if we are at the top
-   * level. */
-  char *runbegin;
-
-  /* The list of segments we are accumulating. */
-  upb_pb_encoder_segment *segbuf, *segptr, *seglimit;
-
-  /* The stack of enclosing submessages.  Each entry in the stack points to the
-   * segment where this submessage's length is being accumulated. */
-  int *stack, *top, *stacklimit;
-
-  /* Depth of startmsg/endmsg calls. */
-  int depth;
-};
-
-/* low-level buffering ********************************************************/
-
-/* Low-level functions for interacting with the output buffer. */
-
-/* TODO(haberman): handle pushback */
-static void putbuf(upb_pb_encoder *e, const char *buf, size_t len) {
-  size_t n = upb_bytessink_putbuf(e->output_, e->subc, buf, len, NULL);
-  UPB_ASSERT_VAR(n, n == len);
-}
-
-static upb_pb_encoder_segment *top(upb_pb_encoder *e) {
-  return &e->segbuf[*e->top];
-}
-
-/* Call to ensure that at least "bytes" bytes are available for writing at
- * e->ptr.  Returns false if the bytes could not be allocated. */
-static bool reserve(upb_pb_encoder *e, size_t bytes) {
-  if ((size_t)(e->limit - e->ptr) < bytes) {
-    /* Grow buffer. */
-    char *new_buf;
-    size_t needed = bytes + (e->ptr - e->buf);
-    size_t old_size = e->limit - e->buf;
-
-    size_t new_size = old_size;
-
-    while (new_size < needed) {
-      new_size *= 2;
-    }
-
-    new_buf = upb_env_realloc(e->env, e->buf, old_size, new_size);
-
-    if (new_buf == NULL) {
-      return false;
-    }
-
-    e->ptr = new_buf + (e->ptr - e->buf);
-    e->runbegin = new_buf + (e->runbegin - e->buf);
-    e->limit = new_buf + new_size;
-    e->buf = new_buf;
-  }
-
-  return true;
-}
-
-/* Call when "bytes" bytes have been writte at e->ptr.  The caller *must* have
- * previously called reserve() with at least this many bytes. */
-static void encoder_advance(upb_pb_encoder *e, size_t bytes) {
-  assert((size_t)(e->limit - e->ptr) >= bytes);
-  e->ptr += bytes;
-}
-
-/* Call when all of the bytes for a handler have been written.  Flushes the
- * bytes if possible and necessary, returning false if this failed. */
-static bool commit(upb_pb_encoder *e) {
-  if (!e->top) {
-    /* We aren't inside a delimited region.  Flush our accumulated bytes to
-     * the output.
-     *
-     * TODO(haberman): in the future we may want to delay flushing for
-     * efficiency reasons. */
-    putbuf(e, e->buf, e->ptr - e->buf);
-    e->ptr = e->buf;
-  }
-
-  return true;
-}
-
-/* Writes the given bytes to the buffer, handling reserve/advance. */
-static bool encode_bytes(upb_pb_encoder *e, const void *data, size_t len) {
-  if (!reserve(e, len)) {
-    return false;
-  }
-
-  memcpy(e->ptr, data, len);
-  encoder_advance(e, len);
-  return true;
-}
-
-/* Finish the current run by adding the run totals to the segment and message
- * length. */
-static void accumulate(upb_pb_encoder *e) {
-  size_t run_len;
-  assert(e->ptr >= e->runbegin);
-  run_len = e->ptr - e->runbegin;
-  e->segptr->seglen += run_len;
-  top(e)->msglen += run_len;
-  e->runbegin = e->ptr;
-}
-
-/* Call to indicate the start of delimited region for which the full length is
- * not yet known.  All data will be buffered until the length is known.
- * Delimited regions may be nested; their lengths will all be tracked properly. */
-static bool start_delim(upb_pb_encoder *e) {
-  if (e->top) {
-    /* We are already buffering, advance to the next segment and push it on the
-     * stack. */
-    accumulate(e);
-
-    if (++e->top == e->stacklimit) {
-      /* TODO(haberman): grow stack? */
-      return false;
-    }
-
-    if (++e->segptr == e->seglimit) {
-      /* Grow segment buffer. */
-      size_t old_size =
-          (e->seglimit - e->segbuf) * sizeof(upb_pb_encoder_segment);
-      size_t new_size = old_size * 2;
-      upb_pb_encoder_segment *new_buf =
-          upb_env_realloc(e->env, e->segbuf, old_size, new_size);
-
-      if (new_buf == NULL) {
-        return false;
-      }
-
-      e->segptr = new_buf + (e->segptr - e->segbuf);
-      e->seglimit = new_buf + (new_size / sizeof(upb_pb_encoder_segment));
-      e->segbuf = new_buf;
-    }
-  } else {
-    /* We were previously at the top level, start buffering. */
-    e->segptr = e->segbuf;
-    e->top = e->stack;
-    e->runbegin = e->ptr;
-  }
-
-  *e->top = e->segptr - e->segbuf;
-  e->segptr->seglen = 0;
-  e->segptr->msglen = 0;
-
-  return true;
-}
-
-/* Call to indicate the end of a delimited region.  We now know the length of
- * the delimited region.  If we are not nested inside any other delimited
- * regions, we can now emit all of the buffered data we accumulated. */
-static bool end_delim(upb_pb_encoder *e) {
-  size_t msglen;
-  accumulate(e);
-  msglen = top(e)->msglen;
-
-  if (e->top == e->stack) {
-    /* All lengths are now available, emit all buffered data. */
-    char buf[UPB_PB_VARINT_MAX_LEN];
-    upb_pb_encoder_segment *s;
-    const char *ptr = e->buf;
-    for (s = e->segbuf; s <= e->segptr; s++) {
-      size_t lenbytes = upb_vencode64(s->msglen, buf);
-      putbuf(e, buf, lenbytes);
-      putbuf(e, ptr, s->seglen);
-      ptr += s->seglen;
-    }
-
-    e->ptr = e->buf;
-    e->top = NULL;
-  } else {
-    /* Need to keep buffering; propagate length info into enclosing
-     * submessages. */
-    --e->top;
-    top(e)->msglen += msglen + upb_varint_size(msglen);
-  }
-
-  return true;
-}
-
-
-/* tag_t **********************************************************************/
-
-/* A precomputed (pre-encoded) tag and length. */
-
-typedef struct {
-  uint8_t bytes;
-  char tag[7];
-} tag_t;
-
-/* Allocates a new tag for this field, and sets it in these handlerattr. */
-static void new_tag(upb_handlers *h, const upb_fielddef *f, upb_wiretype_t wt,
-                    upb_handlerattr *attr) {
-  uint32_t n = upb_fielddef_number(f);
-
-  tag_t *tag = malloc(sizeof(tag_t));
-  tag->bytes = upb_vencode64((n << 3) | wt, tag->tag);
-
-  upb_handlerattr_init(attr);
-  upb_handlerattr_sethandlerdata(attr, tag);
-  upb_handlers_addcleanup(h, tag, free);
-}
-
-static bool encode_tag(upb_pb_encoder *e, const tag_t *tag) {
-  return encode_bytes(e, tag->tag, tag->bytes);
-}
-
-
-/* encoding of wire types *****************************************************/
-
-static bool encode_fixed64(upb_pb_encoder *e, uint64_t val) {
-  /* TODO(haberman): byte-swap for big endian. */
-  return encode_bytes(e, &val, sizeof(uint64_t));
-}
-
-static bool encode_fixed32(upb_pb_encoder *e, uint32_t val) {
-  /* TODO(haberman): byte-swap for big endian. */
-  return encode_bytes(e, &val, sizeof(uint32_t));
-}
-
-static bool encode_varint(upb_pb_encoder *e, uint64_t val) {
-  if (!reserve(e, UPB_PB_VARINT_MAX_LEN)) {
-    return false;
-  }
-
-  encoder_advance(e, upb_vencode64(val, e->ptr));
-  return true;
-}
-
-static uint64_t dbl2uint64(double d) {
-  uint64_t ret;
-  memcpy(&ret, &d, sizeof(uint64_t));
-  return ret;
-}
-
-static uint32_t flt2uint32(float d) {
-  uint32_t ret;
-  memcpy(&ret, &d, sizeof(uint32_t));
-  return ret;
-}
-
-
-/* encoding of proto types ****************************************************/
-
-static bool startmsg(void *c, const void *hd) {
-  upb_pb_encoder *e = c;
-  UPB_UNUSED(hd);
-  if (e->depth++ == 0) {
-    upb_bytessink_start(e->output_, 0, &e->subc);
-  }
-  return true;
-}
-
-static bool endmsg(void *c, const void *hd, upb_status *status) {
-  upb_pb_encoder *e = c;
-  UPB_UNUSED(hd);
-  UPB_UNUSED(status);
-  if (--e->depth == 0) {
-    upb_bytessink_end(e->output_);
-  }
-  return true;
-}
-
-static void *encode_startdelimfield(void *c, const void *hd) {
-  bool ok = encode_tag(c, hd) && commit(c) && start_delim(c);
-  return ok ? c : UPB_BREAK;
-}
-
-static bool encode_enddelimfield(void *c, const void *hd) {
-  UPB_UNUSED(hd);
-  return end_delim(c);
-}
-
-static void *encode_startgroup(void *c, const void *hd) {
-  return (encode_tag(c, hd) && commit(c)) ? c : UPB_BREAK;
-}
-
-static bool encode_endgroup(void *c, const void *hd) {
-  return encode_tag(c, hd) && commit(c);
-}
-
-static void *encode_startstr(void *c, const void *hd, size_t size_hint) {
-  UPB_UNUSED(size_hint);
-  return encode_startdelimfield(c, hd);
-}
-
-static size_t encode_strbuf(void *c, const void *hd, const char *buf,
-                            size_t len, const upb_bufhandle *h) {
-  UPB_UNUSED(hd);
-  UPB_UNUSED(h);
-  return encode_bytes(c, buf, len) ? len : 0;
-}
-
-#define T(type, ctype, convert, encode)                                  \
-  static bool encode_scalar_##type(void *e, const void *hd, ctype val) { \
-    return encode_tag(e, hd) && encode(e, (convert)(val)) && commit(e);  \
-  }                                                                      \
-  static bool encode_packed_##type(void *e, const void *hd, ctype val) { \
-    UPB_UNUSED(hd);                                                      \
-    return encode(e, (convert)(val));                                    \
-  }
-
-T(double,   double,   dbl2uint64,   encode_fixed64)
-T(float,    float,    flt2uint32,   encode_fixed32)
-T(int64,    int64_t,  uint64_t,     encode_varint)
-T(int32,    int32_t,  uint32_t,     encode_varint)
-T(fixed64,  uint64_t, uint64_t,     encode_fixed64)
-T(fixed32,  uint32_t, uint32_t,     encode_fixed32)
-T(bool,     bool,     bool,         encode_varint)
-T(uint32,   uint32_t, uint32_t,     encode_varint)
-T(uint64,   uint64_t, uint64_t,     encode_varint)
-T(enum,     int32_t,  uint32_t,     encode_varint)
-T(sfixed32, int32_t,  uint32_t,     encode_fixed32)
-T(sfixed64, int64_t,  uint64_t,     encode_fixed64)
-T(sint32,   int32_t,  upb_zzenc_32, encode_varint)
-T(sint64,   int64_t,  upb_zzenc_64, encode_varint)
-
-#undef T
-
-
-/* code to build the handlers *************************************************/
-
-static void newhandlers_callback(const void *closure, upb_handlers *h) {
-  const upb_msgdef *m;
-  upb_msg_field_iter i;
-
-  UPB_UNUSED(closure);
-
-  upb_handlers_setstartmsg(h, startmsg, NULL);
-  upb_handlers_setendmsg(h, endmsg, NULL);
-
-  m = upb_handlers_msgdef(h);
-  for(upb_msg_field_begin(&i, m);
-      !upb_msg_field_done(&i);
-      upb_msg_field_next(&i)) {
-    const upb_fielddef *f = upb_msg_iter_field(&i);
-    bool packed = upb_fielddef_isseq(f) && upb_fielddef_isprimitive(f) &&
-                  upb_fielddef_packed(f);
-    upb_handlerattr attr;
-    upb_wiretype_t wt =
-        packed ? UPB_WIRE_TYPE_DELIMITED
-               : upb_pb_native_wire_types[upb_fielddef_descriptortype(f)];
-
-    /* Pre-encode the tag for this field. */
-    new_tag(h, f, wt, &attr);
-
-    if (packed) {
-      upb_handlers_setstartseq(h, f, encode_startdelimfield, &attr);
-      upb_handlers_setendseq(h, f, encode_enddelimfield, &attr);
-    }
-
-#define T(upper, lower, upbtype)                                     \
-  case UPB_DESCRIPTOR_TYPE_##upper:                                  \
-    if (packed) {                                                    \
-      upb_handlers_set##upbtype(h, f, encode_packed_##lower, &attr); \
-    } else {                                                         \
-      upb_handlers_set##upbtype(h, f, encode_scalar_##lower, &attr); \
-    }                                                                \
-    break;
-
-    switch (upb_fielddef_descriptortype(f)) {
-      T(DOUBLE,   double,   double);
-      T(FLOAT,    float,    float);
-      T(INT64,    int64,    int64);
-      T(INT32,    int32,    int32);
-      T(FIXED64,  fixed64,  uint64);
-      T(FIXED32,  fixed32,  uint32);
-      T(BOOL,     bool,     bool);
-      T(UINT32,   uint32,   uint32);
-      T(UINT64,   uint64,   uint64);
-      T(ENUM,     enum,     int32);
-      T(SFIXED32, sfixed32, int32);
-      T(SFIXED64, sfixed64, int64);
-      T(SINT32,   sint32,   int32);
-      T(SINT64,   sint64,   int64);
-      case UPB_DESCRIPTOR_TYPE_STRING:
-      case UPB_DESCRIPTOR_TYPE_BYTES:
-        upb_handlers_setstartstr(h, f, encode_startstr, &attr);
-        upb_handlers_setendstr(h, f, encode_enddelimfield, &attr);
-        upb_handlers_setstring(h, f, encode_strbuf, &attr);
-        break;
-      case UPB_DESCRIPTOR_TYPE_MESSAGE:
-        upb_handlers_setstartsubmsg(h, f, encode_startdelimfield, &attr);
-        upb_handlers_setendsubmsg(h, f, encode_enddelimfield, &attr);
-        break;
-      case UPB_DESCRIPTOR_TYPE_GROUP: {
-        /* Endgroup takes a different tag (wire_type = END_GROUP). */
-        upb_handlerattr attr2;
-        new_tag(h, f, UPB_WIRE_TYPE_END_GROUP, &attr2);
-
-        upb_handlers_setstartsubmsg(h, f, encode_startgroup, &attr);
-        upb_handlers_setendsubmsg(h, f, encode_endgroup, &attr2);
-
-        upb_handlerattr_uninit(&attr2);
-        break;
-      }
-    }
-
-#undef T
-
-    upb_handlerattr_uninit(&attr);
-  }
-}
-
-void upb_pb_encoder_reset(upb_pb_encoder *e) {
-  e->segptr = NULL;
-  e->top = NULL;
-  e->depth = 0;
-}
-
-
-/* public API *****************************************************************/
-
-const upb_handlers *upb_pb_encoder_newhandlers(const upb_msgdef *m,
-                                               const void *owner) {
-  return upb_handlers_newfrozen(m, owner, newhandlers_callback, NULL);
-}
-
-upb_pb_encoder *upb_pb_encoder_create(upb_env *env, const upb_handlers *h,
-                                      upb_bytessink *output) {
-  const size_t initial_bufsize = 256;
-  const size_t initial_segbufsize = 16;
-  /* TODO(haberman): make this configurable. */
-  const size_t stack_size = 64;
-#ifndef NDEBUG
-  const size_t size_before = upb_env_bytesallocated(env);
-#endif
-
-  upb_pb_encoder *e = upb_env_malloc(env, sizeof(upb_pb_encoder));
-  if (!e) return NULL;
-
-  e->buf = upb_env_malloc(env, initial_bufsize);
-  e->segbuf = upb_env_malloc(env, initial_segbufsize * sizeof(*e->segbuf));
-  e->stack = upb_env_malloc(env, stack_size * sizeof(*e->stack));
-
-  if (!e->buf || !e->segbuf || !e->stack) {
-    return NULL;
-  }
-
-  e->limit = e->buf + initial_bufsize;
-  e->seglimit = e->segbuf + initial_segbufsize;
-  e->stacklimit = e->stack + stack_size;
-
-  upb_pb_encoder_reset(e);
-  upb_sink_reset(&e->input_, h, e);
-
-  e->env = env;
-  e->output_ = output;
-  e->subc = output->closure;
-  e->ptr = e->buf;
-
-  /* If this fails, increase the value in encoder.h. */
-  assert(upb_env_bytesallocated(env) - size_before <= UPB_PB_ENCODER_SIZE);
-  return e;
-}
-
-upb_sink *upb_pb_encoder_input(upb_pb_encoder *e) { return &e->input_; }
-
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-
-upb_def **upb_load_defs_from_descriptor(const char *str, size_t len, int *n,
-                                        void *owner, upb_status *status) {
-  /* Create handlers. */
-  const upb_pbdecodermethod *decoder_m;
-  const upb_handlers *reader_h = upb_descreader_newhandlers(&reader_h);
-  upb_env env;
-  upb_pbdecodermethodopts opts;
-  upb_pbdecoder *decoder;
-  upb_descreader *reader;
-  bool ok;
-  upb_def **ret = NULL;
-  upb_def **defs;
-
-  upb_pbdecodermethodopts_init(&opts, reader_h);
-  decoder_m = upb_pbdecodermethod_new(&opts, &decoder_m);
-
-  upb_env_init(&env);
-  upb_env_reporterrorsto(&env, status);
-
-  reader = upb_descreader_create(&env, reader_h);
-  decoder = upb_pbdecoder_create(&env, decoder_m, upb_descreader_input(reader));
-
-  /* Push input data. */
-  ok = upb_bufsrc_putbuf(str, len, upb_pbdecoder_input(decoder));
-
-  if (!ok) goto cleanup;
-  defs = upb_descreader_getdefs(reader, owner, n);
-  ret = malloc(sizeof(upb_def*) * (*n));
-  memcpy(ret, defs, sizeof(upb_def*) * (*n));
-
-cleanup:
-  upb_env_uninit(&env);
-  upb_handlers_unref(reader_h, &reader_h);
-  upb_pbdecodermethod_unref(decoder_m, &decoder_m);
-  return ret;
-}
-
-bool upb_load_descriptor_into_symtab(upb_symtab *s, const char *str, size_t len,
-                                     upb_status *status) {
-  int n;
-  bool success;
-  upb_def **defs = upb_load_defs_from_descriptor(str, len, &n, &defs, status);
-  if (!defs) return false;
-  success = upb_symtab_add(s, defs, n, &defs, status);
-  free(defs);
-  return success;
-}
-
-char *upb_readfile(const char *filename, size_t *len) {
-  long size;
-  char *buf;
-  FILE *f = fopen(filename, "rb");
-  if(!f) return NULL;
-  if(fseek(f, 0, SEEK_END) != 0) goto error;
-  size = ftell(f);
-  if(size < 0) goto error;
-  if(fseek(f, 0, SEEK_SET) != 0) goto error;
-  buf = malloc(size + 1);
-  if(size && fread(buf, size, 1, f) != 1) goto error;
-  fclose(f);
-  if (len) *len = size;
-  return buf;
-
-error:
-  fclose(f);
-  return NULL;
-}
-
-bool upb_load_descriptor_file_into_symtab(upb_symtab *symtab, const char *fname,
-                                          upb_status *status) {
-  size_t len;
-  bool success;
-  char *data = upb_readfile(fname, &len);
-  if (!data) {
-    if (status) upb_status_seterrf(status, "Couldn't read file: %s", fname);
-    return false;
-  }
-  success = upb_load_descriptor_into_symtab(symtab, data, len, status);
-  free(data);
-  return success;
-}
-/*
- * upb::pb::TextPrinter
- *
- * OPT: This is not optimized at all.  It uses printf() which parses the format
- * string every time, and it allocates memory for every put.
- */
-
-
-#include <ctype.h>
-#include <float.h>
-#include <inttypes.h>
-#include <stdarg.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-
-
-struct upb_textprinter {
-  upb_sink input_;
-  upb_bytessink *output_;
-  int indent_depth_;
-  bool single_line_;
-  void *subc;
-};
-
-#define CHECK(x) if ((x) < 0) goto err;
-
-static const char *shortname(const char *longname) {
-  const char *last = strrchr(longname, '.');
-  return last ? last + 1 : longname;
-}
-
-static int indent(upb_textprinter *p) {
-  int i;
-  if (!p->single_line_)
-    for (i = 0; i < p->indent_depth_; i++)
-      upb_bytessink_putbuf(p->output_, p->subc, "  ", 2, NULL);
-  return 0;
-}
-
-static int endfield(upb_textprinter *p) {
-  const char ch = (p->single_line_ ? ' ' : '\n');
-  upb_bytessink_putbuf(p->output_, p->subc, &ch, 1, NULL);
-  return 0;
-}
-
-static int putescaped(upb_textprinter *p, const char *buf, size_t len,
-                      bool preserve_utf8) {
-  /* Based on CEscapeInternal() from Google's protobuf release. */
-  char dstbuf[4096], *dst = dstbuf, *dstend = dstbuf + sizeof(dstbuf);
-  const char *end = buf + len;
-
-  /* I think hex is prettier and more useful, but proto2 uses octal; should
-   * investigate whether it can parse hex also. */
-  const bool use_hex = false;
-  bool last_hex_escape = false; /* true if last output char was \xNN */
-
-  for (; buf < end; buf++) {
-    bool is_hex_escape;
-
-    if (dstend - dst < 4) {
-      upb_bytessink_putbuf(p->output_, p->subc, dstbuf, dst - dstbuf, NULL);
-      dst = dstbuf;
-    }
-
-    is_hex_escape = false;
-    switch (*buf) {
-      case '\n': *(dst++) = '\\'; *(dst++) = 'n';  break;
-      case '\r': *(dst++) = '\\'; *(dst++) = 'r';  break;
-      case '\t': *(dst++) = '\\'; *(dst++) = 't';  break;
-      case '\"': *(dst++) = '\\'; *(dst++) = '\"'; break;
-      case '\'': *(dst++) = '\\'; *(dst++) = '\''; break;
-      case '\\': *(dst++) = '\\'; *(dst++) = '\\'; break;
-      default:
-        /* Note that if we emit \xNN and the buf character after that is a hex
-         * digit then that digit must be escaped too to prevent it being
-         * interpreted as part of the character code by C. */
-        if ((!preserve_utf8 || (uint8_t)*buf < 0x80) &&
-            (!isprint(*buf) || (last_hex_escape && isxdigit(*buf)))) {
-          sprintf(dst, (use_hex ? "\\x%02x" : "\\%03o"), (uint8_t)*buf);
-          is_hex_escape = use_hex;
-          dst += 4;
-        } else {
-          *(dst++) = *buf; break;
-        }
-    }
-    last_hex_escape = is_hex_escape;
-  }
-  /* Flush remaining data. */
-  upb_bytessink_putbuf(p->output_, p->subc, dstbuf, dst - dstbuf, NULL);
-  return 0;
-}
-
-bool putf(upb_textprinter *p, const char *fmt, ...) {
-  va_list args;
-  va_list args_copy;
-  char *str;
-  int written;
-  int len;
-  bool ok;
-
-  va_start(args, fmt);
-
-  /* Run once to get the length of the string. */
-  _upb_va_copy(args_copy, args);
-  len = _upb_vsnprintf(NULL, 0, fmt, args_copy);
-  va_end(args_copy);
-
-  /* + 1 for NULL terminator (vsprintf() requires it even if we don't). */
-  str = malloc(len + 1);
-  if (!str) return false;
-  written = vsprintf(str, fmt, args);
-  va_end(args);
-  UPB_ASSERT_VAR(written, written == len);
-
-  ok = upb_bytessink_putbuf(p->output_, p->subc, str, len, NULL);
-  free(str);
-  return ok;
-}
-
-
-/* handlers *******************************************************************/
-
-static bool textprinter_startmsg(void *c, const void *hd) {
-  upb_textprinter *p = c;
-  UPB_UNUSED(hd);
-  if (p->indent_depth_ == 0) {
-    upb_bytessink_start(p->output_, 0, &p->subc);
-  }
-  return true;
-}
-
-static bool textprinter_endmsg(void *c, const void *hd, upb_status *s) {
-  upb_textprinter *p = c;
-  UPB_UNUSED(hd);
-  UPB_UNUSED(s);
-  if (p->indent_depth_ == 0) {
-    upb_bytessink_end(p->output_);
-  }
-  return true;
-}
-
-#define TYPE(name, ctype, fmt) \
-  static bool textprinter_put ## name(void *closure, const void *handler_data, \
-                                      ctype val) {                             \
-    upb_textprinter *p = closure;                                              \
-    const upb_fielddef *f = handler_data;                                      \
-    CHECK(indent(p));                                                          \
-    putf(p, "%s: " fmt, upb_fielddef_name(f), val);                            \
-    CHECK(endfield(p));                                                        \
-    return true;                                                               \
-  err:                                                                         \
-    return false;                                                              \
-}
-
-static bool textprinter_putbool(void *closure, const void *handler_data,
-                                bool val) {
-  upb_textprinter *p = closure;
-  const upb_fielddef *f = handler_data;
-  CHECK(indent(p));
-  putf(p, "%s: %s", upb_fielddef_name(f), val ? "true" : "false");
-  CHECK(endfield(p));
-  return true;
-err:
-  return false;
-}
-
-#define STRINGIFY_HELPER(x) #x
-#define STRINGIFY_MACROVAL(x) STRINGIFY_HELPER(x)
-
-TYPE(int32,  int32_t,  "%" PRId32)
-TYPE(int64,  int64_t,  "%" PRId64)
-TYPE(uint32, uint32_t, "%" PRIu32)
-TYPE(uint64, uint64_t, "%" PRIu64)
-TYPE(float,  float,    "%." STRINGIFY_MACROVAL(FLT_DIG) "g")
-TYPE(double, double,   "%." STRINGIFY_MACROVAL(DBL_DIG) "g")
-
-#undef TYPE
-
-/* Output a symbolic value from the enum if found, else just print as int32. */
-static bool textprinter_putenum(void *closure, const void *handler_data,
-                                int32_t val) {
-  upb_textprinter *p = closure;
-  const upb_fielddef *f = handler_data;
-  const upb_enumdef *enum_def = upb_downcast_enumdef(upb_fielddef_subdef(f));
-  const char *label = upb_enumdef_iton(enum_def, val);
-  if (label) {
-    indent(p);
-    putf(p, "%s: %s", upb_fielddef_name(f), label);
-    endfield(p);
-  } else {
-    if (!textprinter_putint32(closure, handler_data, val))
-      return false;
-  }
-  return true;
-}
-
-static void *textprinter_startstr(void *closure, const void *handler_data,
-                      size_t size_hint) {
-  upb_textprinter *p = closure;
-  const upb_fielddef *f = handler_data;
-  UPB_UNUSED(size_hint);
-  indent(p);
-  putf(p, "%s: \"", upb_fielddef_name(f));
-  return p;
-}
-
-static bool textprinter_endstr(void *closure, const void *handler_data) {
-  upb_textprinter *p = closure;
-  UPB_UNUSED(handler_data);
-  putf(p, "\"");
-  endfield(p);
-  return true;
-}
-
-static size_t textprinter_putstr(void *closure, const void *hd, const char *buf,
-                                 size_t len, const upb_bufhandle *handle) {
-  upb_textprinter *p = closure;
-  const upb_fielddef *f = hd;
-  UPB_UNUSED(handle);
-  CHECK(putescaped(p, buf, len, upb_fielddef_type(f) == UPB_TYPE_STRING));
-  return len;
-err:
-  return 0;
-}
-
-static void *textprinter_startsubmsg(void *closure, const void *handler_data) {
-  upb_textprinter *p = closure;
-  const char *name = handler_data;
-  CHECK(indent(p));
-  putf(p, "%s {%c", name, p->single_line_ ? ' ' : '\n');
-  p->indent_depth_++;
-  return p;
-err:
-  return UPB_BREAK;
-}
-
-static bool textprinter_endsubmsg(void *closure, const void *handler_data) {
-  upb_textprinter *p = closure;
-  UPB_UNUSED(handler_data);
-  p->indent_depth_--;
-  CHECK(indent(p));
-  upb_bytessink_putbuf(p->output_, p->subc, "}", 1, NULL);
-  CHECK(endfield(p));
-  return true;
-err:
-  return false;
-}
-
-static void onmreg(const void *c, upb_handlers *h) {
-  const upb_msgdef *m = upb_handlers_msgdef(h);
-  upb_msg_field_iter i;
-  UPB_UNUSED(c);
-
-  upb_handlers_setstartmsg(h, textprinter_startmsg, NULL);
-  upb_handlers_setendmsg(h, textprinter_endmsg, NULL);
-
-  for(upb_msg_field_begin(&i, m);
-      !upb_msg_field_done(&i);
-      upb_msg_field_next(&i)) {
-    upb_fielddef *f = upb_msg_iter_field(&i);
-    upb_handlerattr attr = UPB_HANDLERATTR_INITIALIZER;
-    upb_handlerattr_sethandlerdata(&attr, f);
-    switch (upb_fielddef_type(f)) {
-      case UPB_TYPE_INT32:
-        upb_handlers_setint32(h, f, textprinter_putint32, &attr);
-        break;
-      case UPB_TYPE_INT64:
-        upb_handlers_setint64(h, f, textprinter_putint64, &attr);
-        break;
-      case UPB_TYPE_UINT32:
-        upb_handlers_setuint32(h, f, textprinter_putuint32, &attr);
-        break;
-      case UPB_TYPE_UINT64:
-        upb_handlers_setuint64(h, f, textprinter_putuint64, &attr);
-        break;
-      case UPB_TYPE_FLOAT:
-        upb_handlers_setfloat(h, f, textprinter_putfloat, &attr);
-        break;
-      case UPB_TYPE_DOUBLE:
-        upb_handlers_setdouble(h, f, textprinter_putdouble, &attr);
-        break;
-      case UPB_TYPE_BOOL:
-        upb_handlers_setbool(h, f, textprinter_putbool, &attr);
-        break;
-      case UPB_TYPE_STRING:
-      case UPB_TYPE_BYTES:
-        upb_handlers_setstartstr(h, f, textprinter_startstr, &attr);
-        upb_handlers_setstring(h, f, textprinter_putstr, &attr);
-        upb_handlers_setendstr(h, f, textprinter_endstr, &attr);
-        break;
-      case UPB_TYPE_MESSAGE: {
-        const char *name =
-            upb_fielddef_istagdelim(f)
-                ? shortname(upb_msgdef_fullname(upb_fielddef_msgsubdef(f)))
-                : upb_fielddef_name(f);
-        upb_handlerattr_sethandlerdata(&attr, name);
-        upb_handlers_setstartsubmsg(h, f, textprinter_startsubmsg, &attr);
-        upb_handlers_setendsubmsg(h, f, textprinter_endsubmsg, &attr);
-        break;
-      }
-      case UPB_TYPE_ENUM:
-        upb_handlers_setint32(h, f, textprinter_putenum, &attr);
-        break;
-    }
-  }
-}
-
-static void textprinter_reset(upb_textprinter *p, bool single_line) {
-  p->single_line_ = single_line;
-  p->indent_depth_ = 0;
-}
-
-
-/* Public API *****************************************************************/
-
-upb_textprinter *upb_textprinter_create(upb_env *env, const upb_handlers *h,
-                                        upb_bytessink *output) {
-  upb_textprinter *p = upb_env_malloc(env, sizeof(upb_textprinter));
-  if (!p) return NULL;
-
-  p->output_ = output;
-  upb_sink_reset(&p->input_, h, p);
-  textprinter_reset(p, false);
-
-  return p;
-}
-
-const upb_handlers *upb_textprinter_newhandlers(const upb_msgdef *m,
-                                                const void *owner) {
-  return upb_handlers_newfrozen(m, owner, &onmreg, NULL);
-}
-
-upb_sink *upb_textprinter_input(upb_textprinter *p) { return &p->input_; }
-
-void upb_textprinter_setsingleline(upb_textprinter *p, bool single_line) {
-  p->single_line_ = single_line;
-}
-
-
-/* Index is descriptor type. */
-const uint8_t upb_pb_native_wire_types[] = {
-  UPB_WIRE_TYPE_END_GROUP,     /* ENDGROUP */
-  UPB_WIRE_TYPE_64BIT,         /* DOUBLE */
-  UPB_WIRE_TYPE_32BIT,         /* FLOAT */
-  UPB_WIRE_TYPE_VARINT,        /* INT64 */
-  UPB_WIRE_TYPE_VARINT,        /* UINT64 */
-  UPB_WIRE_TYPE_VARINT,        /* INT32 */
-  UPB_WIRE_TYPE_64BIT,         /* FIXED64 */
-  UPB_WIRE_TYPE_32BIT,         /* FIXED32 */
-  UPB_WIRE_TYPE_VARINT,        /* BOOL */
-  UPB_WIRE_TYPE_DELIMITED,     /* STRING */
-  UPB_WIRE_TYPE_START_GROUP,   /* GROUP */
-  UPB_WIRE_TYPE_DELIMITED,     /* MESSAGE */
-  UPB_WIRE_TYPE_DELIMITED,     /* BYTES */
-  UPB_WIRE_TYPE_VARINT,        /* UINT32 */
-  UPB_WIRE_TYPE_VARINT,        /* ENUM */
-  UPB_WIRE_TYPE_32BIT,         /* SFIXED32 */
-  UPB_WIRE_TYPE_64BIT,         /* SFIXED64 */
-  UPB_WIRE_TYPE_VARINT,        /* SINT32 */
-  UPB_WIRE_TYPE_VARINT,        /* SINT64 */
-};
-
-/* A basic branch-based decoder, uses 32-bit values to get good performance
- * on 32-bit architectures (but performs well on 64-bits also).
- * This scheme comes from the original Google Protobuf implementation
- * (proto2). */
-upb_decoderet upb_vdecode_max8_branch32(upb_decoderet r) {
-  upb_decoderet err = {NULL, 0};
-  const char *p = r.p;
-  uint32_t low = (uint32_t)r.val;
-  uint32_t high = 0;
-  uint32_t b;
-  b = *(p++); low  |= (b & 0x7fU) << 14; if (!(b & 0x80)) goto done;
-  b = *(p++); low  |= (b & 0x7fU) << 21; if (!(b & 0x80)) goto done;
-  b = *(p++); low  |= (b & 0x7fU) << 28;
-              high  = (b & 0x7fU) >>  4; if (!(b & 0x80)) goto done;
-  b = *(p++); high |= (b & 0x7fU) <<  3; if (!(b & 0x80)) goto done;
-  b = *(p++); high |= (b & 0x7fU) << 10; if (!(b & 0x80)) goto done;
-  b = *(p++); high |= (b & 0x7fU) << 17; if (!(b & 0x80)) goto done;
-  b = *(p++); high |= (b & 0x7fU) << 24; if (!(b & 0x80)) goto done;
-  b = *(p++); high |= (b & 0x7fU) << 31; if (!(b & 0x80)) goto done;
-  return err;
-
-done:
-  r.val = ((uint64_t)high << 32) | low;
-  r.p = p;
-  return r;
-}
-
-/* Like the previous, but uses 64-bit values. */
-upb_decoderet upb_vdecode_max8_branch64(upb_decoderet r) {
-  const char *p = r.p;
-  uint64_t val = r.val;
-  uint64_t b;
-  upb_decoderet err = {NULL, 0};
-  b = *(p++); val |= (b & 0x7fU) << 14; if (!(b & 0x80)) goto done;
-  b = *(p++); val |= (b & 0x7fU) << 21; if (!(b & 0x80)) goto done;
-  b = *(p++); val |= (b & 0x7fU) << 28; if (!(b & 0x80)) goto done;
-  b = *(p++); val |= (b & 0x7fU) << 35; if (!(b & 0x80)) goto done;
-  b = *(p++); val |= (b & 0x7fU) << 42; if (!(b & 0x80)) goto done;
-  b = *(p++); val |= (b & 0x7fU) << 49; if (!(b & 0x80)) goto done;
-  b = *(p++); val |= (b & 0x7fU) << 56; if (!(b & 0x80)) goto done;
-  b = *(p++); val |= (b & 0x7fU) << 63; if (!(b & 0x80)) goto done;
-  return err;
-
-done:
-  r.val = val;
-  r.p = p;
-  return r;
-}
-
-/* Given an encoded varint v, returns an integer with a single bit set that
- * indicates the end of the varint.  Subtracting one from this value will
- * yield a mask that leaves only bits that are part of the varint.  Returns
- * 0 if the varint is unterminated. */
-static uint64_t upb_get_vstopbit(uint64_t v) {
-  uint64_t cbits = v | 0x7f7f7f7f7f7f7f7fULL;
-  return ~cbits & (cbits+1);
-}
-
-/* A branchless decoder.  Credit to Pascal Massimino for the bit-twiddling. */
-upb_decoderet upb_vdecode_max8_massimino(upb_decoderet r) {
-  uint64_t b;
-  uint64_t stop_bit;
-  upb_decoderet my_r;
-  memcpy(&b, r.p, sizeof(b));
-  stop_bit = upb_get_vstopbit(b);
-  b =  (b & 0x7f7f7f7f7f7f7f7fULL) & (stop_bit - 1);
-  b +=       b & 0x007f007f007f007fULL;
-  b +=  3 * (b & 0x0000ffff0000ffffULL);
-  b += 15 * (b & 0x00000000ffffffffULL);
-  if (stop_bit == 0) {
-    /* Error: unterminated varint. */
-    upb_decoderet err_r = {(void*)0, 0};
-    return err_r;
-  }
-  my_r = upb_decoderet_make(r.p + ((__builtin_ctzll(stop_bit) + 1) / 8),
-                            r.val | (b << 7));
-  return my_r;
-}
-
-/* A branchless decoder.  Credit to Daniel Wright for the bit-twiddling. */
-upb_decoderet upb_vdecode_max8_wright(upb_decoderet r) {
-  uint64_t b;
-  uint64_t stop_bit;
-  upb_decoderet my_r;
-  memcpy(&b, r.p, sizeof(b));
-  stop_bit = upb_get_vstopbit(b);
-  b &= (stop_bit - 1);
-  b = ((b & 0x7f007f007f007f00ULL) >> 1) | (b & 0x007f007f007f007fULL);
-  b = ((b & 0xffff0000ffff0000ULL) >> 2) | (b & 0x0000ffff0000ffffULL);
-  b = ((b & 0xffffffff00000000ULL) >> 4) | (b & 0x00000000ffffffffULL);
-  if (stop_bit == 0) {
-    /* Error: unterminated varint. */
-    upb_decoderet err_r = {(void*)0, 0};
-    return err_r;
-  }
-  my_r = upb_decoderet_make(r.p + ((__builtin_ctzll(stop_bit) + 1) / 8),
-                            r.val | (b << 14));
-  return my_r;
-}
-
-#line 1 "upb/json/parser.rl"
-/*
-** upb::json::Parser (upb_json_parser)
-**
-** A parser that uses the Ragel State Machine Compiler to generate
-** the finite automata.
-**
-** Ragel only natively handles regular languages, but we can manually
-** program it a bit to handle context-free languages like JSON, by using
-** the "fcall" and "fret" constructs.
-**
-** This parser can handle the basics, but needs several things to be fleshed
-** out:
-**
-** - handling of unicode escape sequences (including high surrogate pairs).
-** - properly check and report errors for unknown fields, stack overflow,
-**   improper array nesting (or lack of nesting).
-** - handling of base64 sequences with padding characters.
-** - handling of push-back (non-success returns from sink functions).
-** - handling of keys/escape-sequences/etc that span input buffers.
-*/
-
-#include <stdio.h>
-#include <stdint.h>
-#include <assert.h>
-#include <string.h>
-#include <stdlib.h>
-#include <errno.h>
-
-
-#define UPB_JSON_MAX_DEPTH 64
-
-typedef struct {
-  upb_sink sink;
-
-  /* The current message in which we're parsing, and the field whose value we're
-   * expecting next. */
-  const upb_msgdef *m;
-  const upb_fielddef *f;
-
-  /* We are in a repeated-field context, ready to emit mapentries as
-   * submessages. This flag alters the start-of-object (open-brace) behavior to
-   * begin a sequence of mapentry messages rather than a single submessage. */
-  bool is_map;
-
-  /* We are in a map-entry message context. This flag is set when parsing the
-   * value field of a single map entry and indicates to all value-field parsers
-   * (subobjects, strings, numbers, and bools) that the map-entry submessage
-   * should end as soon as the value is parsed. */
-  bool is_mapentry;
-
-  /* If |is_map| or |is_mapentry| is true, |mapfield| refers to the parent
-   * message's map field that we're currently parsing. This differs from |f|
-   * because |f| is the field in the *current* message (i.e., the map-entry
-   * message itself), not the parent's field that leads to this map. */
-  const upb_fielddef *mapfield;
-} upb_jsonparser_frame;
-
-struct upb_json_parser {
-  upb_env *env;
-  upb_byteshandler input_handler_;
-  upb_bytessink input_;
-
-  /* Stack to track the JSON scopes we are in. */
-  upb_jsonparser_frame stack[UPB_JSON_MAX_DEPTH];
-  upb_jsonparser_frame *top;
-  upb_jsonparser_frame *limit;
-
-  upb_status status;
-
-  /* Ragel's internal parsing stack for the parsing state machine. */
-  int current_state;
-  int parser_stack[UPB_JSON_MAX_DEPTH];
-  int parser_top;
-
-  /* The handle for the current buffer. */
-  const upb_bufhandle *handle;
-
-  /* Accumulate buffer.  See details in parser.rl. */
-  const char *accumulated;
-  size_t accumulated_len;
-  char *accumulate_buf;
-  size_t accumulate_buf_size;
-
-  /* Multi-part text data.  See details in parser.rl. */
-  int multipart_state;
-  upb_selector_t string_selector;
-
-  /* Input capture.  See details in parser.rl. */
-  const char *capture;
-
-  /* Intermediate result of parsing a unicode escape sequence. */
-  uint32_t digit;
-};
-
-#define PARSER_CHECK_RETURN(x) if (!(x)) return false
-
-/* Used to signal that a capture has been suspended. */
-static char suspend_capture;
-
-static upb_selector_t getsel_for_handlertype(upb_json_parser *p,
-                                             upb_handlertype_t type) {
-  upb_selector_t sel;
-  bool ok = upb_handlers_getselector(p->top->f, type, &sel);
-  UPB_ASSERT_VAR(ok, ok);
-  return sel;
-}
-
-static upb_selector_t parser_getsel(upb_json_parser *p) {
-  return getsel_for_handlertype(
-      p, upb_handlers_getprimitivehandlertype(p->top->f));
-}
-
-static bool check_stack(upb_json_parser *p) {
-  if ((p->top + 1) == p->limit) {
-    upb_status_seterrmsg(&p->status, "Nesting too deep");
-    upb_env_reporterror(p->env, &p->status);
-    return false;
-  }
-
-  return true;
-}
-
-/* There are GCC/Clang built-ins for overflow checking which we could start
- * using if there was any performance benefit to it. */
-
-static bool checked_add(size_t a, size_t b, size_t *c) {
-  if (SIZE_MAX - a < b) return false;
-  *c = a + b;
-  return true;
-}
-
-static size_t saturating_multiply(size_t a, size_t b) {
-  /* size_t is unsigned, so this is defined behavior even on overflow. */
-  size_t ret = a * b;
-  if (b != 0 && ret / b != a) {
-    ret = SIZE_MAX;
-  }
-  return ret;
-}
-
-
-/* Base64 decoding ************************************************************/
-
-/* TODO(haberman): make this streaming. */
-
-static const signed char b64table[] = {
-  -1,      -1,      -1,      -1,      -1,      -1,      -1,      -1,
-  -1,      -1,      -1,      -1,      -1,      -1,      -1,      -1,
-  -1,      -1,      -1,      -1,      -1,      -1,      -1,      -1,
-  -1,      -1,      -1,      -1,      -1,      -1,      -1,      -1,
-  -1,      -1,      -1,      -1,      -1,      -1,      -1,      -1,
-  -1,      -1,      -1,      62/*+*/, -1,      -1,      -1,      63/*/ */,
-  52/*0*/, 53/*1*/, 54/*2*/, 55/*3*/, 56/*4*/, 57/*5*/, 58/*6*/, 59/*7*/,
-  60/*8*/, 61/*9*/, -1,      -1,      -1,      -1,      -1,      -1,
-  -1,       0/*A*/,  1/*B*/,  2/*C*/,  3/*D*/,  4/*E*/,  5/*F*/,  6/*G*/,
-  07/*H*/,  8/*I*/,  9/*J*/, 10/*K*/, 11/*L*/, 12/*M*/, 13/*N*/, 14/*O*/,
-  15/*P*/, 16/*Q*/, 17/*R*/, 18/*S*/, 19/*T*/, 20/*U*/, 21/*V*/, 22/*W*/,
-  23/*X*/, 24/*Y*/, 25/*Z*/, -1,      -1,      -1,      -1,      -1,
-  -1,      26/*a*/, 27/*b*/, 28/*c*/, 29/*d*/, 30/*e*/, 31/*f*/, 32/*g*/,
-  33/*h*/, 34/*i*/, 35/*j*/, 36/*k*/, 37/*l*/, 38/*m*/, 39/*n*/, 40/*o*/,
-  41/*p*/, 42/*q*/, 43/*r*/, 44/*s*/, 45/*t*/, 46/*u*/, 47/*v*/, 48/*w*/,
-  49/*x*/, 50/*y*/, 51/*z*/, -1,      -1,      -1,      -1,      -1,
-  -1,      -1,      -1,      -1,      -1,      -1,      -1,      -1,
-  -1,      -1,      -1,      -1,      -1,      -1,      -1,      -1,
-  -1,      -1,      -1,      -1,      -1,      -1,      -1,      -1,
-  -1,      -1,      -1,      -1,      -1,      -1,      -1,      -1,
-  -1,      -1,      -1,      -1,      -1,      -1,      -1,      -1,
-  -1,      -1,      -1,      -1,      -1,      -1,      -1,      -1,
-  -1,      -1,      -1,      -1,      -1,      -1,      -1,      -1,
-  -1,      -1,      -1,      -1,      -1,      -1,      -1,      -1,
-  -1,      -1,      -1,      -1,      -1,      -1,      -1,      -1,
-  -1,      -1,      -1,      -1,      -1,      -1,      -1,      -1,
-  -1,      -1,      -1,      -1,      -1,      -1,      -1,      -1,
-  -1,      -1,      -1,      -1,      -1,      -1,      -1,      -1,
-  -1,      -1,      -1,      -1,      -1,      -1,      -1,      -1,
-  -1,      -1,      -1,      -1,      -1,      -1,      -1,      -1,
-  -1,      -1,      -1,      -1,      -1,      -1,      -1,      -1,
-  -1,      -1,      -1,      -1,      -1,      -1,      -1,      -1
-};
-
-/* Returns the table value sign-extended to 32 bits.  Knowing that the upper
- * bits will be 1 for unrecognized characters makes it easier to check for
- * this error condition later (see below). */
-int32_t b64lookup(unsigned char ch) { return b64table[ch]; }
-
-/* Returns true if the given character is not a valid base64 character or
- * padding. */
-bool nonbase64(unsigned char ch) { return b64lookup(ch) == -1 && ch != '='; }
-
-static bool base64_push(upb_json_parser *p, upb_selector_t sel, const char *ptr,
-                        size_t len) {
-  const char *limit = ptr + len;
-  for (; ptr < limit; ptr += 4) {
-    uint32_t val;
-    char output[3];
-
-    if (limit - ptr < 4) {
-      upb_status_seterrf(&p->status,
-                         "Base64 input for bytes field not a multiple of 4: %s",
-                         upb_fielddef_name(p->top->f));
-      upb_env_reporterror(p->env, &p->status);
-      return false;
-    }
-
-    val = b64lookup(ptr[0]) << 18 |
-          b64lookup(ptr[1]) << 12 |
-          b64lookup(ptr[2]) << 6  |
-          b64lookup(ptr[3]);
-
-    /* Test the upper bit; returns true if any of the characters returned -1. */
-    if (val & 0x80000000) {
-      goto otherchar;
-    }
-
-    output[0] = val >> 16;
-    output[1] = (val >> 8) & 0xff;
-    output[2] = val & 0xff;
-    upb_sink_putstring(&p->top->sink, sel, output, 3, NULL);
-  }
-  return true;
-
-otherchar:
-  if (nonbase64(ptr[0]) || nonbase64(ptr[1]) || nonbase64(ptr[2]) ||
-      nonbase64(ptr[3]) ) {
-    upb_status_seterrf(&p->status,
-                       "Non-base64 characters in bytes field: %s",
-                       upb_fielddef_name(p->top->f));
-    upb_env_reporterror(p->env, &p->status);
-    return false;
-  } if (ptr[2] == '=') {
-    uint32_t val;
-    char output;
-
-    /* Last group contains only two input bytes, one output byte. */
-    if (ptr[0] == '=' || ptr[1] == '=' || ptr[3] != '=') {
-      goto badpadding;
-    }
-
-    val = b64lookup(ptr[0]) << 18 |
-          b64lookup(ptr[1]) << 12;
-
-    assert(!(val & 0x80000000));
-    output = val >> 16;
-    upb_sink_putstring(&p->top->sink, sel, &output, 1, NULL);
-    return true;
-  } else {
-    uint32_t val;
-    char output[2];
-
-    /* Last group contains only three input bytes, two output bytes. */
-    if (ptr[0] == '=' || ptr[1] == '=' || ptr[2] == '=') {
-      goto badpadding;
-    }
-
-    val = b64lookup(ptr[0]) << 18 |
-          b64lookup(ptr[1]) << 12 |
-          b64lookup(ptr[2]) << 6;
-
-    output[0] = val >> 16;
-    output[1] = (val >> 8) & 0xff;
-    upb_sink_putstring(&p->top->sink, sel, output, 2, NULL);
-    return true;
-  }
-
-badpadding:
-  upb_status_seterrf(&p->status,
-                     "Incorrect base64 padding for field: %s (%.*s)",
-                     upb_fielddef_name(p->top->f),
-                     4, ptr);
-  upb_env_reporterror(p->env, &p->status);
-  return false;
-}
-
-
-/* Accumulate buffer **********************************************************/
-
-/* Functionality for accumulating a buffer.
- *
- * Some parts of the parser need an entire value as a contiguous string.  For
- * example, to look up a member name in a hash table, or to turn a string into
- * a number, the relevant library routines need the input string to be in
- * contiguous memory, even if the value spanned two or more buffers in the
- * input.  These routines handle that.
- *
- * In the common case we can just point to the input buffer to get this
- * contiguous string and avoid any actual copy.  So we optimistically begin
- * this way.  But there are a few cases where we must instead copy into a
- * separate buffer:
- *
- *   1. The string was not contiguous in the input (it spanned buffers).
- *
- *   2. The string included escape sequences that need to be interpreted to get
- *      the true value in a contiguous buffer. */
-
-static void assert_accumulate_empty(upb_json_parser *p) {
-  UPB_UNUSED(p);
-  assert(p->accumulated == NULL);
-  assert(p->accumulated_len == 0);
-}
-
-static void accumulate_clear(upb_json_parser *p) {
-  p->accumulated = NULL;
-  p->accumulated_len = 0;
-}
-
-/* Used internally by accumulate_append(). */
-static bool accumulate_realloc(upb_json_parser *p, size_t need) {
-  void *mem;
-  size_t old_size = p->accumulate_buf_size;
-  size_t new_size = UPB_MAX(old_size, 128);
-  while (new_size < need) {
-    new_size = saturating_multiply(new_size, 2);
-  }
-
-  mem = upb_env_realloc(p->env, p->accumulate_buf, old_size, new_size);
-  if (!mem) {
-    upb_status_seterrmsg(&p->status, "Out of memory allocating buffer.");
-    upb_env_reporterror(p->env, &p->status);
-    return false;
-  }
-
-  p->accumulate_buf = mem;
-  p->accumulate_buf_size = new_size;
-  return true;
-}
-
-/* Logically appends the given data to the append buffer.
- * If "can_alias" is true, we will try to avoid actually copying, but the buffer
- * must be valid until the next accumulate_append() call (if any). */
-static bool accumulate_append(upb_json_parser *p, const char *buf, size_t len,
-                              bool can_alias) {
-  size_t need;
-
-  if (!p->accumulated && can_alias) {
-    p->accumulated = buf;
-    p->accumulated_len = len;
-    return true;
-  }
-
-  if (!checked_add(p->accumulated_len, len, &need)) {
-    upb_status_seterrmsg(&p->status, "Integer overflow.");
-    upb_env_reporterror(p->env, &p->status);
-    return false;
-  }
-
-  if (need > p->accumulate_buf_size && !accumulate_realloc(p, need)) {
-    return false;
-  }
-
-  if (p->accumulated != p->accumulate_buf) {
-    memcpy(p->accumulate_buf, p->accumulated, p->accumulated_len);
-    p->accumulated = p->accumulate_buf;
-  }
-
-  memcpy(p->accumulate_buf + p->accumulated_len, buf, len);
-  p->accumulated_len += len;
-  return true;
-}
-
-/* Returns a pointer to the data accumulated since the last accumulate_clear()
- * call, and writes the length to *len.  This with point either to the input
- * buffer or a temporary accumulate buffer. */
-static const char *accumulate_getptr(upb_json_parser *p, size_t *len) {
-  assert(p->accumulated);
-  *len = p->accumulated_len;
-  return p->accumulated;
-}
-
-
-/* Mult-part text data ********************************************************/
-
-/* When we have text data in the input, it can often come in multiple segments.
- * For example, there may be some raw string data followed by an escape
- * sequence.  The two segments are processed with different logic.  Also buffer
- * seams in the input can cause multiple segments.
- *
- * As we see segments, there are two main cases for how we want to process them:
- *
- *  1. we want to push the captured input directly to string handlers.
- *
- *  2. we need to accumulate all the parts into a contiguous buffer for further
- *     processing (field name lookup, string->number conversion, etc). */
-
-/* This is the set of states for p->multipart_state. */
-enum {
-  /* We are not currently processing multipart data. */
-  MULTIPART_INACTIVE = 0,
-
-  /* We are processing multipart data by accumulating it into a contiguous
-   * buffer. */
-  MULTIPART_ACCUMULATE = 1,
-
-  /* We are processing multipart data by pushing each part directly to the
-   * current string handlers. */
-  MULTIPART_PUSHEAGERLY = 2
-};
-
-/* Start a multi-part text value where we accumulate the data for processing at
- * the end. */
-static void multipart_startaccum(upb_json_parser *p) {
-  assert_accumulate_empty(p);
-  assert(p->multipart_state == MULTIPART_INACTIVE);
-  p->multipart_state = MULTIPART_ACCUMULATE;
-}
-
-/* Start a multi-part text value where we immediately push text data to a string
- * value with the given selector. */
-static void multipart_start(upb_json_parser *p, upb_selector_t sel) {
-  assert_accumulate_empty(p);
-  assert(p->multipart_state == MULTIPART_INACTIVE);
-  p->multipart_state = MULTIPART_PUSHEAGERLY;
-  p->string_selector = sel;
-}
-
-static bool multipart_text(upb_json_parser *p, const char *buf, size_t len,
-                           bool can_alias) {
-  switch (p->multipart_state) {
-    case MULTIPART_INACTIVE:
-      upb_status_seterrmsg(
-          &p->status, "Internal error: unexpected state MULTIPART_INACTIVE");
-      upb_env_reporterror(p->env, &p->status);
-      return false;
-
-    case MULTIPART_ACCUMULATE:
-      if (!accumulate_append(p, buf, len, can_alias)) {
-        return false;
-      }
-      break;
-
-    case MULTIPART_PUSHEAGERLY: {
-      const upb_bufhandle *handle = can_alias ? p->handle : NULL;
-      upb_sink_putstring(&p->top->sink, p->string_selector, buf, len, handle);
-      break;
-    }
-  }
-
-  return true;
-}
-
-/* Note: this invalidates the accumulate buffer!  Call only after reading its
- * contents. */
-static void multipart_end(upb_json_parser *p) {
-  assert(p->multipart_state != MULTIPART_INACTIVE);
-  p->multipart_state = MULTIPART_INACTIVE;
-  accumulate_clear(p);
-}
-
-
-/* Input capture **************************************************************/
-
-/* Functionality for capturing a region of the input as text.  Gracefully
- * handles the case where a buffer seam occurs in the middle of the captured
- * region. */
-
-static void capture_begin(upb_json_parser *p, const char *ptr) {
-  assert(p->multipart_state != MULTIPART_INACTIVE);
-  assert(p->capture == NULL);
-  p->capture = ptr;
-}
-
-static bool capture_end(upb_json_parser *p, const char *ptr) {
-  assert(p->capture);
-  if (multipart_text(p, p->capture, ptr - p->capture, true)) {
-    p->capture = NULL;
-    return true;
-  } else {
-    return false;
-  }
-}
-
-/* This is called at the end of each input buffer (ie. when we have hit a
- * buffer seam).  If we are in the middle of capturing the input, this
- * processes the unprocessed capture region. */
-static void capture_suspend(upb_json_parser *p, const char **ptr) {
-  if (!p->capture) return;
-
-  if (multipart_text(p, p->capture, *ptr - p->capture, false)) {
-    /* We use this as a signal that we were in the middle of capturing, and
-     * that capturing should resume at the beginning of the next buffer.
-     * 
-     * We can't use *ptr here, because we have no guarantee that this pointer
-     * will be valid when we resume (if the underlying memory is freed, then
-     * using the pointer at all, even to compare to NULL, is likely undefined
-     * behavior). */
-    p->capture = &suspend_capture;
-  } else {
-    /* Need to back up the pointer to the beginning of the capture, since
-     * we were not able to actually preserve it. */
-    *ptr = p->capture;
-  }
-}
-
-static void capture_resume(upb_json_parser *p, const char *ptr) {
-  if (p->capture) {
-    assert(p->capture == &suspend_capture);
-    p->capture = ptr;
-  }
-}
-
-
-/* Callbacks from the parser **************************************************/
-
-/* These are the functions called directly from the parser itself.
- * We define these in the same order as their declarations in the parser. */
-
-static char escape_char(char in) {
-  switch (in) {
-    case 'r': return '\r';
-    case 't': return '\t';
-    case 'n': return '\n';
-    case 'f': return '\f';
-    case 'b': return '\b';
-    case '/': return '/';
-    case '"': return '"';
-    case '\\': return '\\';
-    default:
-      assert(0);
-      return 'x';
-  }
-}
-
-static bool escape(upb_json_parser *p, const char *ptr) {
-  char ch = escape_char(*ptr);
-  return multipart_text(p, &ch, 1, false);
-}
-
-static void start_hex(upb_json_parser *p) {
-  p->digit = 0;
-}
-
-static void hexdigit(upb_json_parser *p, const char *ptr) {
-  char ch = *ptr;
-
-  p->digit <<= 4;
-
-  if (ch >= '0' && ch <= '9') {
-    p->digit += (ch - '0');
-  } else if (ch >= 'a' && ch <= 'f') {
-    p->digit += ((ch - 'a') + 10);
-  } else {
-    assert(ch >= 'A' && ch <= 'F');
-    p->digit += ((ch - 'A') + 10);
-  }
-}
-
-static bool end_hex(upb_json_parser *p) {
-  uint32_t codepoint = p->digit;
-
-  /* emit the codepoint as UTF-8. */
-  char utf8[3]; /* support \u0000 -- \uFFFF -- need only three bytes. */
-  int length = 0;
-  if (codepoint <= 0x7F) {
-    utf8[0] = codepoint;
-    length = 1;
-  } else if (codepoint <= 0x07FF) {
-    utf8[1] = (codepoint & 0x3F) | 0x80;
-    codepoint >>= 6;
-    utf8[0] = (codepoint & 0x1F) | 0xC0;
-    length = 2;
-  } else /* codepoint <= 0xFFFF */ {
-    utf8[2] = (codepoint & 0x3F) | 0x80;
-    codepoint >>= 6;
-    utf8[1] = (codepoint & 0x3F) | 0x80;
-    codepoint >>= 6;
-    utf8[0] = (codepoint & 0x0F) | 0xE0;
-    length = 3;
-  }
-  /* TODO(haberman): Handle high surrogates: if codepoint is a high surrogate
-   * we have to wait for the next escape to get the full code point). */
-
-  return multipart_text(p, utf8, length, false);
-}
-
-static void start_text(upb_json_parser *p, const char *ptr) {
-  capture_begin(p, ptr);
-}
-
-static bool end_text(upb_json_parser *p, const char *ptr) {
-  return capture_end(p, ptr);
-}
-
-static void start_number(upb_json_parser *p, const char *ptr) {
-  multipart_startaccum(p);
-  capture_begin(p, ptr);
-}
-
-static bool parse_number(upb_json_parser *p);
-
-static bool end_number(upb_json_parser *p, const char *ptr) {
-  if (!capture_end(p, ptr)) {
-    return false;
-  }
-
-  return parse_number(p);
-}
-
-static bool parse_number(upb_json_parser *p) {
-  size_t len;
-  const char *buf;
-  const char *myend;
-  char *end;
-
-  /* strtol() and friends unfortunately do not support specifying the length of
-   * the input string, so we need to force a copy into a NULL-terminated buffer. */
-  if (!multipart_text(p, "\0", 1, false)) {
-    return false;
-  }
-
-  buf = accumulate_getptr(p, &len);
-  myend = buf + len - 1;  /* One for NULL. */
-
-  /* XXX: We are using strtol to parse integers, but this is wrong as even
-   * integers can be represented as 1e6 (for example), which strtol can't
-   * handle correctly.
-   *
-   * XXX: Also, we can't handle large integers properly because strto[u]ll
-   * isn't in C89.
-   *
-   * XXX: Also, we don't properly check floats for overflow, since strtof
-   * isn't in C89. */
-  switch (upb_fielddef_type(p->top->f)) {
-    case UPB_TYPE_ENUM:
-    case UPB_TYPE_INT32: {
-      long val = strtol(p->accumulated, &end, 0);
-      if (val > INT32_MAX || val < INT32_MIN || errno == ERANGE || end != myend)
-        goto err;
-      else
-        upb_sink_putint32(&p->top->sink, parser_getsel(p), val);
-      break;
-    }
-    case UPB_TYPE_INT64: {
-      long long val = strtol(p->accumulated, &end, 0);
-      if (val > INT64_MAX || val < INT64_MIN || errno == ERANGE || end != myend)
-        goto err;
-      else
-        upb_sink_putint64(&p->top->sink, parser_getsel(p), val);
-      break;
-    }
-    case UPB_TYPE_UINT32: {
-      unsigned long val = strtoul(p->accumulated, &end, 0);
-      if (val > UINT32_MAX || errno == ERANGE || end != myend)
-        goto err;
-      else
-        upb_sink_putuint32(&p->top->sink, parser_getsel(p), val);
-      break;
-    }
-    case UPB_TYPE_UINT64: {
-      unsigned long long val = strtoul(p->accumulated, &end, 0);
-      if (val > UINT64_MAX || errno == ERANGE || end != myend)
-        goto err;
-      else
-        upb_sink_putuint64(&p->top->sink, parser_getsel(p), val);
-      break;
-    }
-    case UPB_TYPE_DOUBLE: {
-      double val = strtod(p->accumulated, &end);
-      if (errno == ERANGE || end != myend)
-        goto err;
-      else
-        upb_sink_putdouble(&p->top->sink, parser_getsel(p), val);
-      break;
-    }
-    case UPB_TYPE_FLOAT: {
-      float val = strtod(p->accumulated, &end);
-      if (errno == ERANGE || end != myend)
-        goto err;
-      else
-        upb_sink_putfloat(&p->top->sink, parser_getsel(p), val);
-      break;
-    }
-    default:
-      assert(false);
-  }
-
-  multipart_end(p);
-
-  return true;
-
-err:
-  upb_status_seterrf(&p->status, "error parsing number: %s", buf);
-  upb_env_reporterror(p->env, &p->status);
-  multipart_end(p);
-  return false;
-}
-
-static bool parser_putbool(upb_json_parser *p, bool val) {
-  bool ok;
-
-  if (upb_fielddef_type(p->top->f) != UPB_TYPE_BOOL) {
-    upb_status_seterrf(&p->status,
-                       "Boolean value specified for non-bool field: %s",
-                       upb_fielddef_name(p->top->f));
-    upb_env_reporterror(p->env, &p->status);
-    return false;
-  }
-
-  ok = upb_sink_putbool(&p->top->sink, parser_getsel(p), val);
-  UPB_ASSERT_VAR(ok, ok);
-
-  return true;
-}
-
-static bool start_stringval(upb_json_parser *p) {
-  assert(p->top->f);
-
-  if (upb_fielddef_isstring(p->top->f)) {
-    upb_jsonparser_frame *inner;
-    upb_selector_t sel;
-
-    if (!check_stack(p)) return false;
-
-    /* Start a new parser frame: parser frames correspond one-to-one with
-     * handler frames, and string events occur in a sub-frame. */
-    inner = p->top + 1;
-    sel = getsel_for_handlertype(p, UPB_HANDLER_STARTSTR);
-    upb_sink_startstr(&p->top->sink, sel, 0, &inner->sink);
-    inner->m = p->top->m;
-    inner->f = p->top->f;
-    inner->is_map = false;
-    inner->is_mapentry = false;
-    p->top = inner;
-
-    if (upb_fielddef_type(p->top->f) == UPB_TYPE_STRING) {
-      /* For STRING fields we push data directly to the handlers as it is
-       * parsed.  We don't do this yet for BYTES fields, because our base64
-       * decoder is not streaming.
-       *
-       * TODO(haberman): make base64 decoding streaming also. */
-      multipart_start(p, getsel_for_handlertype(p, UPB_HANDLER_STRING));
-      return true;
-    } else {
-      multipart_startaccum(p);
-      return true;
-    }
-  } else if (upb_fielddef_type(p->top->f) == UPB_TYPE_ENUM) {
-    /* No need to push a frame -- symbolic enum names in quotes remain in the
-     * current parser frame.
-     *
-     * Enum string values must accumulate so we can look up the value in a table
-     * once it is complete. */
-    multipart_startaccum(p);
-    return true;
-  } else {
-    upb_status_seterrf(&p->status,
-                       "String specified for non-string/non-enum field: %s",
-                       upb_fielddef_name(p->top->f));
-    upb_env_reporterror(p->env, &p->status);
-    return false;
-  }
-}
-
-static bool end_stringval(upb_json_parser *p) {
-  bool ok = true;
-
-  switch (upb_fielddef_type(p->top->f)) {
-    case UPB_TYPE_BYTES:
-      if (!base64_push(p, getsel_for_handlertype(p, UPB_HANDLER_STRING),
-                       p->accumulated, p->accumulated_len)) {
-        return false;
-      }
-      /* Fall through. */
-
-    case UPB_TYPE_STRING: {
-      upb_selector_t sel = getsel_for_handlertype(p, UPB_HANDLER_ENDSTR);
-      upb_sink_endstr(&p->top->sink, sel);
-      p->top--;
-      break;
-    }
-
-    case UPB_TYPE_ENUM: {
-      /* Resolve enum symbolic name to integer value. */
-      const upb_enumdef *enumdef =
-          (const upb_enumdef*)upb_fielddef_subdef(p->top->f);
-
-      size_t len;
-      const char *buf = accumulate_getptr(p, &len);
-
-      int32_t int_val = 0;
-      ok = upb_enumdef_ntoi(enumdef, buf, len, &int_val);
-
-      if (ok) {
-        upb_selector_t sel = parser_getsel(p);
-        upb_sink_putint32(&p->top->sink, sel, int_val);
-      } else {
-        upb_status_seterrf(&p->status, "Enum value unknown: '%.*s'", len, buf);
-        upb_env_reporterror(p->env, &p->status);
-      }
-
-      break;
-    }
-
-    default:
-      assert(false);
-      upb_status_seterrmsg(&p->status, "Internal error in JSON decoder");
-      upb_env_reporterror(p->env, &p->status);
-      ok = false;
-      break;
-  }
-
-  multipart_end(p);
-
-  return ok;
-}
-
-static void start_member(upb_json_parser *p) {
-  assert(!p->top->f);
-  multipart_startaccum(p);
-}
-
-/* Helper: invoked during parse_mapentry() to emit the mapentry message's key
- * field based on the current contents of the accumulate buffer. */
-static bool parse_mapentry_key(upb_json_parser *p) {
-
-  size_t len;
-  const char *buf = accumulate_getptr(p, &len);
-
-  /* Emit the key field. We do a bit of ad-hoc parsing here because the
-   * parser state machine has already decided that this is a string field
-   * name, and we are reinterpreting it as some arbitrary key type. In
-   * particular, integer and bool keys are quoted, so we need to parse the
-   * quoted string contents here. */
-
-  p->top->f = upb_msgdef_itof(p->top->m, UPB_MAPENTRY_KEY);
-  if (p->top->f == NULL) {
-    upb_status_seterrmsg(&p->status, "mapentry message has no key");
-    upb_env_reporterror(p->env, &p->status);
-    return false;
-  }
-  switch (upb_fielddef_type(p->top->f)) {
-    case UPB_TYPE_INT32:
-    case UPB_TYPE_INT64:
-    case UPB_TYPE_UINT32:
-    case UPB_TYPE_UINT64:
-      /* Invoke end_number. The accum buffer has the number's text already. */
-      if (!parse_number(p)) {
-        return false;
-      }
-      break;
-    case UPB_TYPE_BOOL:
-      if (len == 4 && !strncmp(buf, "true", 4)) {
-        if (!parser_putbool(p, true)) {
-          return false;
-        }
-      } else if (len == 5 && !strncmp(buf, "false", 5)) {
-        if (!parser_putbool(p, false)) {
-          return false;
-        }
-      } else {
-        upb_status_seterrmsg(&p->status,
-                             "Map bool key not 'true' or 'false'");
-        upb_env_reporterror(p->env, &p->status);
-        return false;
-      }
-      multipart_end(p);
-      break;
-    case UPB_TYPE_STRING:
-    case UPB_TYPE_BYTES: {
-      upb_sink subsink;
-      upb_selector_t sel = getsel_for_handlertype(p, UPB_HANDLER_STARTSTR);
-      upb_sink_startstr(&p->top->sink, sel, len, &subsink);
-      sel = getsel_for_handlertype(p, UPB_HANDLER_STRING);
-      upb_sink_putstring(&subsink, sel, buf, len, NULL);
-      sel = getsel_for_handlertype(p, UPB_HANDLER_ENDSTR);
-      upb_sink_endstr(&subsink, sel);
-      multipart_end(p);
-      break;
-    }
-    default:
-      upb_status_seterrmsg(&p->status, "Invalid field type for map key");
-      upb_env_reporterror(p->env, &p->status);
-      return false;
-  }
-
-  return true;
-}
-
-/* Helper: emit one map entry (as a submessage in the map field sequence). This
- * is invoked from end_membername(), at the end of the map entry's key string,
- * with the map key in the accumulate buffer. It parses the key from that
- * buffer, emits the handler calls to start the mapentry submessage (setting up
- * its subframe in the process), and sets up state in the subframe so that the
- * value parser (invoked next) will emit the mapentry's value field and then
- * end the mapentry message. */
-
-static bool handle_mapentry(upb_json_parser *p) {
-  const upb_fielddef *mapfield;
-  const upb_msgdef *mapentrymsg;
-  upb_jsonparser_frame *inner;
-  upb_selector_t sel;
-
-  /* Map entry: p->top->sink is the seq frame, so we need to start a frame
-   * for the mapentry itself, and then set |f| in that frame so that the map
-   * value field is parsed, and also set a flag to end the frame after the
-   * map-entry value is parsed. */
-  if (!check_stack(p)) return false;
-
-  mapfield = p->top->mapfield;
-  mapentrymsg = upb_fielddef_msgsubdef(mapfield);
-
-  inner = p->top + 1;
-  p->top->f = mapfield;
-  sel = getsel_for_handlertype(p, UPB_HANDLER_STARTSUBMSG);
-  upb_sink_startsubmsg(&p->top->sink, sel, &inner->sink);
-  inner->m = mapentrymsg;
-  inner->mapfield = mapfield;
-  inner->is_map = false;
-
-  /* Don't set this to true *yet* -- we reuse parsing handlers below to push
-   * the key field value to the sink, and these handlers will pop the frame
-   * if they see is_mapentry (when invoked by the parser state machine, they
-   * would have just seen the map-entry value, not key). */
-  inner->is_mapentry = false;
-  p->top = inner;
-
-  /* send STARTMSG in submsg frame. */
-  upb_sink_startmsg(&p->top->sink);
-
-  parse_mapentry_key(p);
-
-  /* Set up the value field to receive the map-entry value. */
-  p->top->f = upb_msgdef_itof(p->top->m, UPB_MAPENTRY_VALUE);
-  p->top->is_mapentry = true;  /* set up to pop frame after value is parsed. */
-  p->top->mapfield = mapfield;
-  if (p->top->f == NULL) {
-    upb_status_seterrmsg(&p->status, "mapentry message has no value");
-    upb_env_reporterror(p->env, &p->status);
-    return false;
-  }
-
-  return true;
-}
-
-static bool end_membername(upb_json_parser *p) {
-  assert(!p->top->f);
-
-  if (p->top->is_map) {
-    return handle_mapentry(p);
-  } else {
-    size_t len;
-    const char *buf = accumulate_getptr(p, &len);
-    const upb_fielddef *f = upb_msgdef_ntof(p->top->m, buf, len);
-
-    if (!f) {
-      /* TODO(haberman): Ignore unknown fields if requested/configured to do
-       * so. */
-      upb_status_seterrf(&p->status, "No such field: %.*s\n", (int)len, buf);
-      upb_env_reporterror(p->env, &p->status);
-      return false;
-    }
-
-    p->top->f = f;
-    multipart_end(p);
-
-    return true;
-  }
-}
-
-static void end_member(upb_json_parser *p) {
-  /* If we just parsed a map-entry value, end that frame too. */
-  if (p->top->is_mapentry) {
-    upb_status s = UPB_STATUS_INIT;
-    upb_selector_t sel;
-    bool ok;
-    const upb_fielddef *mapfield;
-
-    assert(p->top > p->stack);
-    /* send ENDMSG on submsg. */
-    upb_sink_endmsg(&p->top->sink, &s);
-    mapfield = p->top->mapfield;
-
-    /* send ENDSUBMSG in repeated-field-of-mapentries frame. */
-    p->top--;
-    ok = upb_handlers_getselector(mapfield, UPB_HANDLER_ENDSUBMSG, &sel);
-    UPB_ASSERT_VAR(ok, ok);
-    upb_sink_endsubmsg(&p->top->sink, sel);
-  }
-
-  p->top->f = NULL;
-}
-
-static bool start_subobject(upb_json_parser *p) {
-  assert(p->top->f);
-
-  if (upb_fielddef_ismap(p->top->f)) {
-    upb_jsonparser_frame *inner;
-    upb_selector_t sel;
-
-    /* Beginning of a map. Start a new parser frame in a repeated-field
-     * context. */
-    if (!check_stack(p)) return false;
-
-    inner = p->top + 1;
-    sel = getsel_for_handlertype(p, UPB_HANDLER_STARTSEQ);
-    upb_sink_startseq(&p->top->sink, sel, &inner->sink);
-    inner->m = upb_fielddef_msgsubdef(p->top->f);
-    inner->mapfield = p->top->f;
-    inner->f = NULL;
-    inner->is_map = true;
-    inner->is_mapentry = false;
-    p->top = inner;
-
-    return true;
-  } else if (upb_fielddef_issubmsg(p->top->f)) {
-    upb_jsonparser_frame *inner;
-    upb_selector_t sel;
-
-    /* Beginning of a subobject. Start a new parser frame in the submsg
-     * context. */
-    if (!check_stack(p)) return false;
-
-    inner = p->top + 1;
-
-    sel = getsel_for_handlertype(p, UPB_HANDLER_STARTSUBMSG);
-    upb_sink_startsubmsg(&p->top->sink, sel, &inner->sink);
-    inner->m = upb_fielddef_msgsubdef(p->top->f);
-    inner->f = NULL;
-    inner->is_map = false;
-    inner->is_mapentry = false;
-    p->top = inner;
-
-    return true;
-  } else {
-    upb_status_seterrf(&p->status,
-                       "Object specified for non-message/group field: %s",
-                       upb_fielddef_name(p->top->f));
-    upb_env_reporterror(p->env, &p->status);
-    return false;
-  }
-}
-
-static void end_subobject(upb_json_parser *p) {
-  if (p->top->is_map) {
-    upb_selector_t sel;
-    p->top--;
-    sel = getsel_for_handlertype(p, UPB_HANDLER_ENDSEQ);
-    upb_sink_endseq(&p->top->sink, sel);
-  } else {
-    upb_selector_t sel;
-    p->top--;
-    sel = getsel_for_handlertype(p, UPB_HANDLER_ENDSUBMSG);
-    upb_sink_endsubmsg(&p->top->sink, sel);
-  }
-}
-
-static bool start_array(upb_json_parser *p) {
-  upb_jsonparser_frame *inner;
-  upb_selector_t sel;
-
-  assert(p->top->f);
-
-  if (!upb_fielddef_isseq(p->top->f)) {
-    upb_status_seterrf(&p->status,
-                       "Array specified for non-repeated field: %s",
-                       upb_fielddef_name(p->top->f));
-    upb_env_reporterror(p->env, &p->status);
-    return false;
-  }
-
-  if (!check_stack(p)) return false;
-
-  inner = p->top + 1;
-  sel = getsel_for_handlertype(p, UPB_HANDLER_STARTSEQ);
-  upb_sink_startseq(&p->top->sink, sel, &inner->sink);
-  inner->m = p->top->m;
-  inner->f = p->top->f;
-  inner->is_map = false;
-  inner->is_mapentry = false;
-  p->top = inner;
-
-  return true;
-}
-
-static void end_array(upb_json_parser *p) {
-  upb_selector_t sel;
-
-  assert(p->top > p->stack);
-
-  p->top--;
-  sel = getsel_for_handlertype(p, UPB_HANDLER_ENDSEQ);
-  upb_sink_endseq(&p->top->sink, sel);
-}
-
-static void start_object(upb_json_parser *p) {
-  if (!p->top->is_map) {
-    upb_sink_startmsg(&p->top->sink);
-  }
-}
-
-static void end_object(upb_json_parser *p) {
-  if (!p->top->is_map) {
-    upb_status status;
-    upb_status_clear(&status);
-    upb_sink_endmsg(&p->top->sink, &status);
-    if (!upb_ok(&status)) {
-      upb_env_reporterror(p->env, &status);
-    }
-  }
-}
-
-
-#define CHECK_RETURN_TOP(x) if (!(x)) goto error
-
-
-/* The actual parser **********************************************************/
-
-/* What follows is the Ragel parser itself.  The language is specified in Ragel
- * and the actions call our C functions above.
- *
- * Ragel has an extensive set of functionality, and we use only a small part of
- * it.  There are many action types but we only use a few:
- *
- *   ">" -- transition into a machine
- *   "%" -- transition out of a machine
- *   "@" -- transition into a final state of a machine.
- *
- * "@" transitions are tricky because a machine can transition into a final
- * state repeatedly.  But in some cases we know this can't happen, for example
- * a string which is delimited by a final '"' can only transition into its
- * final state once, when the closing '"' is seen. */
-
-
-#line 1218 "upb/json/parser.rl"
-
-
-
-#line 1130 "upb/json/parser.c"
-static const char _json_actions[] = {
-        0, 1, 0, 1, 2, 1, 3, 1, 
-        5, 1, 6, 1, 7, 1, 8, 1, 
-        10, 1, 12, 1, 13, 1, 14, 1, 
-        15, 1, 16, 1, 17, 1, 21, 1, 
-        25, 1, 27, 2, 3, 8, 2, 4, 
-        5, 2, 6, 2, 2, 6, 8, 2, 
-        11, 9, 2, 13, 15, 2, 14, 15, 
-        2, 18, 1, 2, 19, 27, 2, 20, 
-        9, 2, 22, 27, 2, 23, 27, 2, 
-        24, 27, 2, 26, 27, 3, 14, 11, 
-        9
-};
-
-static const unsigned char _json_key_offsets[] = {
-        0, 0, 4, 9, 14, 15, 19, 24, 
-        29, 34, 38, 42, 45, 48, 50, 54, 
-        58, 60, 62, 67, 69, 71, 80, 86, 
-        92, 98, 104, 106, 115, 116, 116, 116, 
-        121, 126, 131, 132, 133, 134, 135, 135, 
-        136, 137, 138, 138, 139, 140, 141, 141, 
-        146, 151, 152, 156, 161, 166, 171, 175, 
-        175, 178, 178, 178
-};
-
-static const char _json_trans_keys[] = {
-        32, 123, 9, 13, 32, 34, 125, 9, 
-        13, 32, 34, 125, 9, 13, 34, 32, 
-        58, 9, 13, 32, 93, 125, 9, 13, 
-        32, 44, 125, 9, 13, 32, 44, 125, 
-        9, 13, 32, 34, 9, 13, 45, 48, 
-        49, 57, 48, 49, 57, 46, 69, 101, 
-        48, 57, 69, 101, 48, 57, 43, 45, 
-        48, 57, 48, 57, 48, 57, 46, 69, 
-        101, 48, 57, 34, 92, 34, 92, 34, 
-        47, 92, 98, 102, 110, 114, 116, 117, 
-        48, 57, 65, 70, 97, 102, 48, 57, 
-        65, 70, 97, 102, 48, 57, 65, 70, 
-        97, 102, 48, 57, 65, 70, 97, 102, 
-        34, 92, 34, 45, 91, 102, 110, 116, 
-        123, 48, 57, 34, 32, 93, 125, 9, 
-        13, 32, 44, 93, 9, 13, 32, 93, 
-        125, 9, 13, 97, 108, 115, 101, 117, 
-        108, 108, 114, 117, 101, 32, 34, 125, 
-        9, 13, 32, 34, 125, 9, 13, 34, 
-        32, 58, 9, 13, 32, 93, 125, 9, 
-        13, 32, 44, 125, 9, 13, 32, 44, 
-        125, 9, 13, 32, 34, 9, 13, 32, 
-        9, 13, 0
-};
-
-static const char _json_single_lengths[] = {
-        0, 2, 3, 3, 1, 2, 3, 3, 
-        3, 2, 2, 1, 3, 0, 2, 2, 
-        0, 0, 3, 2, 2, 9, 0, 0, 
-        0, 0, 2, 7, 1, 0, 0, 3, 
-        3, 3, 1, 1, 1, 1, 0, 1, 
-        1, 1, 0, 1, 1, 1, 0, 3, 
-        3, 1, 2, 3, 3, 3, 2, 0, 
-        1, 0, 0, 0
-};
-
-static const char _json_range_lengths[] = {
-        0, 1, 1, 1, 0, 1, 1, 1, 
-        1, 1, 1, 1, 0, 1, 1, 1, 
-        1, 1, 1, 0, 0, 0, 3, 3, 
-        3, 3, 0, 1, 0, 0, 0, 1, 
-        1, 1, 0, 0, 0, 0, 0, 0, 
-        0, 0, 0, 0, 0, 0, 0, 1, 
-        1, 0, 1, 1, 1, 1, 1, 0, 
-        1, 0, 0, 0
-};
-
-static const short _json_index_offsets[] = {
-        0, 0, 4, 9, 14, 16, 20, 25, 
-        30, 35, 39, 43, 46, 50, 52, 56, 
-        60, 62, 64, 69, 72, 75, 85, 89, 
-        93, 97, 101, 104, 113, 115, 116, 117, 
-        122, 127, 132, 134, 136, 138, 140, 141, 
-        143, 145, 147, 148, 150, 152, 154, 155, 
-        160, 165, 167, 171, 176, 181, 186, 190, 
-        191, 194, 195, 196
-};
-
-static const char _json_indicies[] = {
-        0, 2, 0, 1, 3, 4, 5, 3, 
-        1, 6, 7, 8, 6, 1, 9, 1, 
-        10, 11, 10, 1, 11, 1, 1, 11, 
-        12, 13, 14, 15, 13, 1, 16, 17, 
-        8, 16, 1, 17, 7, 17, 1, 18, 
-        19, 20, 1, 19, 20, 1, 22, 23, 
-        23, 21, 24, 1, 23, 23, 24, 21, 
-        25, 25, 26, 1, 26, 1, 26, 21, 
-        22, 23, 23, 20, 21, 28, 29, 27, 
-        31, 32, 30, 33, 33, 33, 33, 33, 
-        33, 33, 33, 34, 1, 35, 35, 35, 
-        1, 36, 36, 36, 1, 37, 37, 37, 
-        1, 38, 38, 38, 1, 40, 41, 39, 
-        42, 43, 44, 45, 46, 47, 48, 43, 
-        1, 49, 1, 50, 51, 53, 54, 1, 
-        53, 52, 55, 56, 54, 55, 1, 56, 
-        1, 1, 56, 52, 57, 1, 58, 1, 
-        59, 1, 60, 1, 61, 62, 1, 63, 
-        1, 64, 1, 65, 66, 1, 67, 1, 
-        68, 1, 69, 70, 71, 72, 70, 1, 
-        73, 74, 75, 73, 1, 76, 1, 77, 
-        78, 77, 1, 78, 1, 1, 78, 79, 
-        80, 81, 82, 80, 1, 83, 84, 75, 
-        83, 1, 84, 74, 84, 1, 85, 86, 
-        86, 1, 1, 1, 1, 0
-};
-
-static const char _json_trans_targs[] = {
-        1, 0, 2, 3, 4, 56, 3, 4, 
-        56, 5, 5, 6, 7, 8, 9, 56, 
-        8, 9, 11, 12, 18, 57, 13, 15, 
-        14, 16, 17, 20, 58, 21, 20, 58, 
-        21, 19, 22, 23, 24, 25, 26, 20, 
-        58, 21, 28, 30, 31, 34, 39, 43, 
-        47, 29, 59, 59, 32, 31, 29, 32, 
-        33, 35, 36, 37, 38, 59, 40, 41, 
-        42, 59, 44, 45, 46, 59, 48, 49, 
-        55, 48, 49, 55, 50, 50, 51, 52, 
-        53, 54, 55, 53, 54, 59, 56
-};
-
-static const char _json_trans_actions[] = {
-        0, 0, 0, 21, 77, 53, 0, 47, 
-        23, 17, 0, 0, 15, 19, 19, 50, 
-        0, 0, 0, 0, 0, 1, 0, 0, 
-        0, 0, 0, 3, 13, 0, 0, 35, 
-        5, 11, 0, 38, 7, 7, 7, 41, 
-        44, 9, 62, 56, 25, 0, 0, 0, 
-        31, 29, 33, 59, 15, 0, 27, 0, 
-        0, 0, 0, 0, 0, 68, 0, 0, 
-        0, 71, 0, 0, 0, 65, 21, 77, 
-        53, 0, 47, 23, 17, 0, 0, 15, 
-        19, 19, 50, 0, 0, 74, 0
-};
-
-static const int json_start = 1;
-
-static const int json_en_number_machine = 10;
-static const int json_en_string_machine = 19;
-static const int json_en_value_machine = 27;
-static const int json_en_main = 1;
-
-
-#line 1221 "upb/json/parser.rl"
-
-size_t parse(void *closure, const void *hd, const char *buf, size_t size,
-             const upb_bufhandle *handle) {
-  upb_json_parser *parser = closure;
-
-  /* Variables used by Ragel's generated code. */
-  int cs = parser->current_state;
-  int *stack = parser->parser_stack;
-  int top = parser->parser_top;
-
-  const char *p = buf;
-  const char *pe = buf + size;
-
-  parser->handle = handle;
-
-  UPB_UNUSED(hd);
-  UPB_UNUSED(handle);
-
-  capture_resume(parser, buf);
-
-  
-#line 1301 "upb/json/parser.c"
-        {
-        int _klen;
-        unsigned int _trans;
-        const char *_acts;
-        unsigned int _nacts;
-        const char *_keys;
-
-        if ( p == pe )
-                goto _test_eof;
-        if ( cs == 0 )
-                goto _out;
-_resume:
-        _keys = _json_trans_keys + _json_key_offsets[cs];
-        _trans = _json_index_offsets[cs];
-
-        _klen = _json_single_lengths[cs];
-        if ( _klen > 0 ) {
-                const char *_lower = _keys;
-                const char *_mid;
-                const char *_upper = _keys + _klen - 1;
-                while (1) {
-                        if ( _upper < _lower )
-                                break;
-
-                        _mid = _lower + ((_upper-_lower) >> 1);
-                        if ( (*p) < *_mid )
-                                _upper = _mid - 1;
-                        else if ( (*p) > *_mid )
-                                _lower = _mid + 1;
-                        else {
-                                _trans += (unsigned int)(_mid - _keys);
-                                goto _match;
-                        }
-                }
-                _keys += _klen;
-                _trans += _klen;
-        }
-
-        _klen = _json_range_lengths[cs];
-        if ( _klen > 0 ) {
-                const char *_lower = _keys;
-                const char *_mid;
-                const char *_upper = _keys + (_klen<<1) - 2;
-                while (1) {
-                        if ( _upper < _lower )
-                                break;
-
-                        _mid = _lower + (((_upper-_lower) >> 1) & ~1);
-                        if ( (*p) < _mid[0] )
-                                _upper = _mid - 2;
-                        else if ( (*p) > _mid[1] )
-                                _lower = _mid + 2;
-                        else {
-                                _trans += (unsigned int)((_mid - _keys)>>1);
-                                goto _match;
-                        }
-                }
-                _trans += _klen;
-        }
-
-_match:
-        _trans = _json_indicies[_trans];
-        cs = _json_trans_targs[_trans];
-
-        if ( _json_trans_actions[_trans] == 0 )
-                goto _again;
-
-        _acts = _json_actions + _json_trans_actions[_trans];
-        _nacts = (unsigned int) *_acts++;
-        while ( _nacts-- > 0 )
-        {
-                switch ( *_acts++ )
-                {
-        case 0:
-#line 1133 "upb/json/parser.rl"
-        { p--; {cs = stack[--top]; goto _again;} }
-        break;
-        case 1:
-#line 1134 "upb/json/parser.rl"
-        { p--; {stack[top++] = cs; cs = 10; goto _again;} }
-        break;
-        case 2:
-#line 1138 "upb/json/parser.rl"
-        { start_text(parser, p); }
-        break;
-        case 3:
-#line 1139 "upb/json/parser.rl"
-        { CHECK_RETURN_TOP(end_text(parser, p)); }
-        break;
-        case 4:
-#line 1145 "upb/json/parser.rl"
-        { start_hex(parser); }
-        break;
-        case 5:
-#line 1146 "upb/json/parser.rl"
-        { hexdigit(parser, p); }
-        break;
-        case 6:
-#line 1147 "upb/json/parser.rl"
-        { CHECK_RETURN_TOP(end_hex(parser)); }
-        break;
-        case 7:
-#line 1153 "upb/json/parser.rl"
-        { CHECK_RETURN_TOP(escape(parser, p)); }
-        break;
-        case 8:
-#line 1159 "upb/json/parser.rl"
-        { p--; {cs = stack[--top]; goto _again;} }
-        break;
-        case 9:
-#line 1162 "upb/json/parser.rl"
-        { {stack[top++] = cs; cs = 19; goto _again;} }
-        break;
-        case 10:
-#line 1164 "upb/json/parser.rl"
-        { p--; {stack[top++] = cs; cs = 27; goto _again;} }
-        break;
-        case 11:
-#line 1169 "upb/json/parser.rl"
-        { start_member(parser); }
-        break;
-        case 12:
-#line 1170 "upb/json/parser.rl"
-        { CHECK_RETURN_TOP(end_membername(parser)); }
-        break;
-        case 13:
-#line 1173 "upb/json/parser.rl"
-        { end_member(parser); }
-        break;
-        case 14:
-#line 1179 "upb/json/parser.rl"
-        { start_object(parser); }
-        break;
-        case 15:
-#line 1182 "upb/json/parser.rl"
-        { end_object(parser); }
-        break;
-        case 16:
-#line 1188 "upb/json/parser.rl"
-        { CHECK_RETURN_TOP(start_array(parser)); }
-        break;
-        case 17:
-#line 1192 "upb/json/parser.rl"
-        { end_array(parser); }
-        break;
-        case 18:
-#line 1197 "upb/json/parser.rl"
-        { start_number(parser, p); }
-        break;
-        case 19:
-#line 1198 "upb/json/parser.rl"
-        { CHECK_RETURN_TOP(end_number(parser, p)); }
-        break;
-        case 20:
-#line 1200 "upb/json/parser.rl"
-        { CHECK_RETURN_TOP(start_stringval(parser)); }
-        break;
-        case 21:
-#line 1201 "upb/json/parser.rl"
-        { CHECK_RETURN_TOP(end_stringval(parser)); }
-        break;
-        case 22:
-#line 1203 "upb/json/parser.rl"
-        { CHECK_RETURN_TOP(parser_putbool(parser, true)); }
-        break;
-        case 23:
-#line 1205 "upb/json/parser.rl"
-        { CHECK_RETURN_TOP(parser_putbool(parser, false)); }
-        break;
-        case 24:
-#line 1207 "upb/json/parser.rl"
-        { /* null value */ }
-        break;
-        case 25:
-#line 1209 "upb/json/parser.rl"
-        { CHECK_RETURN_TOP(start_subobject(parser)); }
-        break;
-        case 26:
-#line 1210 "upb/json/parser.rl"
-        { end_subobject(parser); }
-        break;
-        case 27:
-#line 1215 "upb/json/parser.rl"
-        { p--; {cs = stack[--top]; goto _again;} }
-        break;
-#line 1487 "upb/json/parser.c"
-                }
-        }
-
-_again:
-        if ( cs == 0 )
-                goto _out;
-        if ( ++p != pe )
-                goto _resume;
-        _test_eof: {}
-        _out: {}
-        }
-
-#line 1242 "upb/json/parser.rl"
-
-  if (p != pe) {
-    upb_status_seterrf(&parser->status, "Parse error at %s\n", p);
-    upb_env_reporterror(parser->env, &parser->status);
-  } else {
-    capture_suspend(parser, &p);
-  }
-
-error:
-  /* Save parsing state back to parser. */
-  parser->current_state = cs;
-  parser->parser_top = top;
-
-  return p - buf;
-}
-
-bool end(void *closure, const void *hd) {
-  UPB_UNUSED(closure);
-  UPB_UNUSED(hd);
-
-  /* Prevent compile warning on unused static constants. */
-  UPB_UNUSED(json_start);
-  UPB_UNUSED(json_en_number_machine);
-  UPB_UNUSED(json_en_string_machine);
-  UPB_UNUSED(json_en_value_machine);
-  UPB_UNUSED(json_en_main);
-  return true;
-}
-
-static void json_parser_reset(upb_json_parser *p) {
-  int cs;
-  int top;
-
-  p->top = p->stack;
-  p->top->f = NULL;
-  p->top->is_map = false;
-  p->top->is_mapentry = false;
-
-  /* Emit Ragel initialization of the parser. */
-  
-#line 1541 "upb/json/parser.c"
-        {
-        cs = json_start;
-        top = 0;
-        }
-
-#line 1282 "upb/json/parser.rl"
-  p->current_state = cs;
-  p->parser_top = top;
-  accumulate_clear(p);
-  p->multipart_state = MULTIPART_INACTIVE;
-  p->capture = NULL;
-  p->accumulated = NULL;
-  upb_status_clear(&p->status);
-}
-
-
-/* Public API *****************************************************************/
-
-upb_json_parser *upb_json_parser_create(upb_env *env, upb_sink *output) {
-#ifndef NDEBUG
-  const size_t size_before = upb_env_bytesallocated(env);
-#endif
-  upb_json_parser *p = upb_env_malloc(env, sizeof(upb_json_parser));
-  if (!p) return false;
-
-  p->env = env;
-  p->limit = p->stack + UPB_JSON_MAX_DEPTH;
-  p->accumulate_buf = NULL;
-  p->accumulate_buf_size = 0;
-  upb_byteshandler_init(&p->input_handler_);
-  upb_byteshandler_setstring(&p->input_handler_, parse, NULL);
-  upb_byteshandler_setendstr(&p->input_handler_, end, NULL);
-  upb_bytessink_reset(&p->input_, &p->input_handler_, p);
-
-  json_parser_reset(p);
-  upb_sink_reset(&p->top->sink, output->handlers, output->closure);
-  p->top->m = upb_handlers_msgdef(output->handlers);
-
-  /* If this fails, uncomment and increase the value in parser.h. */
-  /* fprintf(stderr, "%zd\n", upb_env_bytesallocated(env) - size_before); */
-  assert(upb_env_bytesallocated(env) - size_before <= UPB_JSON_PARSER_SIZE);
-  return p;
-}
-
-upb_bytessink *upb_json_parser_input(upb_json_parser *p) {
-  return &p->input_;
-}
-/*
-** This currently uses snprintf() to format primitives, and could be optimized
-** further.
-*/
-
-
-#include <stdlib.h>
-#include <stdio.h>
-#include <string.h>
-#include <stdint.h>
-
-struct upb_json_printer {
-  upb_sink input_;
-  /* BytesSink closure. */
-  void *subc_;
-  upb_bytessink *output_;
-
-  /* We track the depth so that we know when to emit startstr/endstr on the
-   * output. */
-  int depth_;
-
-  /* Have we emitted the first element? This state is necessary to emit commas
-   * without leaving a trailing comma in arrays/maps. We keep this state per
-   * frame depth.
-   *
-   * Why max_depth * 2? UPB_MAX_HANDLER_DEPTH counts depth as nested messages.
-   * We count frames (contexts in which we separate elements by commas) as both
-   * repeated fields and messages (maps), and the worst case is a
-   * message->repeated field->submessage->repeated field->... nesting. */
-  bool first_elem_[UPB_MAX_HANDLER_DEPTH * 2];
-};
-
-/* StringPiece; a pointer plus a length. */
-typedef struct {
-  const char *ptr;
-  size_t len;
-} strpc;
-
-strpc *newstrpc(upb_handlers *h, const upb_fielddef *f) {
-  strpc *ret = malloc(sizeof(*ret));
-  ret->ptr = upb_fielddef_name(f);
-  ret->len = strlen(ret->ptr);
-  upb_handlers_addcleanup(h, ret, free);
-  return ret;
-}
-
-/* ------------ JSON string printing: values, maps, arrays ------------------ */
-
-static void print_data(
-    upb_json_printer *p, const char *buf, unsigned int len) {
-  /* TODO: Will need to change if we support pushback from the sink. */
-  size_t n = upb_bytessink_putbuf(p->output_, p->subc_, buf, len, NULL);
-  UPB_ASSERT_VAR(n, n == len);
-}
-
-static void print_comma(upb_json_printer *p) {
-  if (!p->first_elem_[p->depth_]) {
-    print_data(p, ",", 1);
-  }
-  p->first_elem_[p->depth_] = false;
-}
-
-/* Helpers that print properly formatted elements to the JSON output stream. */
-
-/* Used for escaping control chars in strings. */
-static const char kControlCharLimit = 0x20;
-
-UPB_INLINE bool is_json_escaped(char c) {
-  /* See RFC 4627. */
-  unsigned char uc = (unsigned char)c;
-  return uc < kControlCharLimit || uc == '"' || uc == '\\';
-}
-
-UPB_INLINE char* json_nice_escape(char c) {
-  switch (c) {
-    case '"':  return "\\\"";
-    case '\\': return "\\\\";
-    case '\b': return "\\b";
-    case '\f': return "\\f";
-    case '\n': return "\\n";
-    case '\r': return "\\r";
-    case '\t': return "\\t";
-    default:   return NULL;
-  }
-}
-
-/* Write a properly escaped string chunk. The surrounding quotes are *not*
- * printed; this is so that the caller has the option of emitting the string
- * content in chunks. */
-static void putstring(upb_json_printer *p, const char *buf, unsigned int len) {
-  const char* unescaped_run = NULL;
-  unsigned int i;
-  for (i = 0; i < len; i++) {
-    char c = buf[i];
-    /* Handle escaping. */
-    if (is_json_escaped(c)) {
-      /* Use a "nice" escape, like \n, if one exists for this character. */
-      const char* escape = json_nice_escape(c);
-      /* If we don't have a specific 'nice' escape code, use a \uXXXX-style
-       * escape. */
-      char escape_buf[8];
-      if (!escape) {
-        unsigned char byte = (unsigned char)c;
-        _upb_snprintf(escape_buf, sizeof(escape_buf), "\\u%04x", (int)byte);
-        escape = escape_buf;
-      }
-
-      /* N.B. that we assume that the input encoding is equal to the output
-       * encoding (both UTF-8 for  now), so for chars >= 0x20 and != \, ", we
-       * can simply pass the bytes through. */
-
-      /* If there's a current run of unescaped chars, print that run first. */
-      if (unescaped_run) {
-        print_data(p, unescaped_run, &buf[i] - unescaped_run);
-        unescaped_run = NULL;
-      }
-      /* Then print the escape code. */
-      print_data(p, escape, strlen(escape));
-    } else {
-      /* Add to the current unescaped run of characters. */
-      if (unescaped_run == NULL) {
-        unescaped_run = &buf[i];
-      }
-    }
-  }
-
-  /* If the string ended in a run of unescaped characters, print that last run. */
-  if (unescaped_run) {
-    print_data(p, unescaped_run, &buf[len] - unescaped_run);
-  }
-}
-
-#define CHKLENGTH(x) if (!(x)) return -1;
-
-/* Helpers that format floating point values according to our custom formats.
- * Right now we use %.8g and %.17g for float/double, respectively, to match
- * proto2::util::JsonFormat's defaults.  May want to change this later. */
-
-static size_t fmt_double(double val, char* buf, size_t length) {
-  size_t n = _upb_snprintf(buf, length, "%.17g", val);
-  CHKLENGTH(n > 0 && n < length);
-  return n;
-}
-
-static size_t fmt_float(float val, char* buf, size_t length) {
-  size_t n = _upb_snprintf(buf, length, "%.8g", val);
-  CHKLENGTH(n > 0 && n < length);
-  return n;
-}
-
-static size_t fmt_bool(bool val, char* buf, size_t length) {
-  size_t n = _upb_snprintf(buf, length, "%s", (val ? "true" : "false"));
-  CHKLENGTH(n > 0 && n < length);
-  return n;
-}
-
-static size_t fmt_int64(long val, char* buf, size_t length) {
-  size_t n = _upb_snprintf(buf, length, "%ld", val);
-  CHKLENGTH(n > 0 && n < length);
-  return n;
-}
-
-static size_t fmt_uint64(unsigned long long val, char* buf, size_t length) {
-  size_t n = _upb_snprintf(buf, length, "%llu", val);
-  CHKLENGTH(n > 0 && n < length);
-  return n;
-}
-
-/* Print a map key given a field name. Called by scalar field handlers and by
- * startseq for repeated fields. */
-static bool putkey(void *closure, const void *handler_data) {
-  upb_json_printer *p = closure;
-  const strpc *key = handler_data;
-  print_comma(p);
-  print_data(p, "\"", 1);
-  putstring(p, key->ptr, key->len);
-  print_data(p, "\":", 2);
-  return true;
-}
-
-#define CHKFMT(val) if ((val) == (size_t)-1) return false;
-#define CHK(val)    if (!(val)) return false;
-
-#define TYPE_HANDLERS(type, fmt_func)                                        \
-  static bool put##type(void *closure, const void *handler_data, type val) { \
-    upb_json_printer *p = closure;                                           \
-    char data[64];                                                           \
-    size_t length = fmt_func(val, data, sizeof(data));                       \
-    UPB_UNUSED(handler_data);                                                \
-    CHKFMT(length);                                                          \
-    print_data(p, data, length);                                             \
-    return true;                                                             \
-  }                                                                          \
-  static bool scalar_##type(void *closure, const void *handler_data,         \
-                            type val) {                                      \
-    CHK(putkey(closure, handler_data));                                      \
-    CHK(put##type(closure, handler_data, val));                              \
-    return true;                                                             \
-  }                                                                          \
-  static bool repeated_##type(void *closure, const void *handler_data,       \
-                              type val) {                                    \
-    upb_json_printer *p = closure;                                           \
-    print_comma(p);                                                          \
-    CHK(put##type(closure, handler_data, val));                              \
-    return true;                                                             \
-  }
-
-#define TYPE_HANDLERS_MAPKEY(type, fmt_func)                                 \
-  static bool putmapkey_##type(void *closure, const void *handler_data,      \
-                            type val) {                                      \
-    upb_json_printer *p = closure;                                           \
-    print_data(p, "\"", 1);                                                  \
-    CHK(put##type(closure, handler_data, val));                              \
-    print_data(p, "\":", 2);                                                 \
-    return true;                                                             \
-  }
-
-TYPE_HANDLERS(double,   fmt_double)
-TYPE_HANDLERS(float,    fmt_float)
-TYPE_HANDLERS(bool,     fmt_bool)
-TYPE_HANDLERS(int32_t,  fmt_int64)
-TYPE_HANDLERS(uint32_t, fmt_int64)
-TYPE_HANDLERS(int64_t,  fmt_int64)
-TYPE_HANDLERS(uint64_t, fmt_uint64)
-
-/* double and float are not allowed to be map keys. */
-TYPE_HANDLERS_MAPKEY(bool,     fmt_bool)
-TYPE_HANDLERS_MAPKEY(int32_t,  fmt_int64)
-TYPE_HANDLERS_MAPKEY(uint32_t, fmt_int64)
-TYPE_HANDLERS_MAPKEY(int64_t,  fmt_int64)
-TYPE_HANDLERS_MAPKEY(uint64_t, fmt_uint64)
-
-#undef TYPE_HANDLERS
-#undef TYPE_HANDLERS_MAPKEY
-
-typedef struct {
-  void *keyname;
-  const upb_enumdef *enumdef;
-} EnumHandlerData;
-
-static bool scalar_enum(void *closure, const void *handler_data,
-                        int32_t val) {
-  const EnumHandlerData *hd = handler_data;
-  upb_json_printer *p = closure;
-  const char *symbolic_name;
-
-  CHK(putkey(closure, hd->keyname));
-
-  symbolic_name = upb_enumdef_iton(hd->enumdef, val);
-  if (symbolic_name) {
-    print_data(p, "\"", 1);
-    putstring(p, symbolic_name, strlen(symbolic_name));
-    print_data(p, "\"", 1);
-  } else {
-    putint32_t(closure, NULL, val);
-  }
-
-  return true;
-}
-
-static void print_enum_symbolic_name(upb_json_printer *p,
-                                     const upb_enumdef *def,
-                                     int32_t val) {
-  const char *symbolic_name = upb_enumdef_iton(def, val);
-  if (symbolic_name) {
-    print_data(p, "\"", 1);
-    putstring(p, symbolic_name, strlen(symbolic_name));
-    print_data(p, "\"", 1);
-  } else {
-    putint32_t(p, NULL, val);
-  }
-}
-
-static bool repeated_enum(void *closure, const void *handler_data,
-                          int32_t val) {
-  const EnumHandlerData *hd = handler_data;
-  upb_json_printer *p = closure;
-  print_comma(p);
-
-  print_enum_symbolic_name(p, hd->enumdef, val);
-
-  return true;
-}
-
-static bool mapvalue_enum(void *closure, const void *handler_data,
-                          int32_t val) {
-  const EnumHandlerData *hd = handler_data;
-  upb_json_printer *p = closure;
-
-  print_enum_symbolic_name(p, hd->enumdef, val);
-
-  return true;
-}
-
-static void *scalar_startsubmsg(void *closure, const void *handler_data) {
-  return putkey(closure, handler_data) ? closure : UPB_BREAK;
-}
-
-static void *repeated_startsubmsg(void *closure, const void *handler_data) {
-  upb_json_printer *p = closure;
-  UPB_UNUSED(handler_data);
-  print_comma(p);
-  return closure;
-}
-
-static void start_frame(upb_json_printer *p) {
-  p->depth_++;
-  p->first_elem_[p->depth_] = true;
-  print_data(p, "{", 1);
-}
-
-static void end_frame(upb_json_printer *p) {
-  print_data(p, "}", 1);
-  p->depth_--;
-}
-
-static bool printer_startmsg(void *closure, const void *handler_data) {
-  upb_json_printer *p = closure;
-  UPB_UNUSED(handler_data);
-  if (p->depth_ == 0) {
-    upb_bytessink_start(p->output_, 0, &p->subc_);
-  }
-  start_frame(p);
-  return true;
-}
-
-static bool printer_endmsg(void *closure, const void *handler_data, upb_status *s) {
-  upb_json_printer *p = closure;
-  UPB_UNUSED(handler_data);
-  UPB_UNUSED(s);
-  end_frame(p);
-  if (p->depth_ == 0) {
-    upb_bytessink_end(p->output_);
-  }
-  return true;
-}
-
-static void *startseq(void *closure, const void *handler_data) {
-  upb_json_printer *p = closure;
-  CHK(putkey(closure, handler_data));
-  p->depth_++;
-  p->first_elem_[p->depth_] = true;
-  print_data(p, "[", 1);
-  return closure;
-}
-
-static bool endseq(void *closure, const void *handler_data) {
-  upb_json_printer *p = closure;
-  UPB_UNUSED(handler_data);
-  print_data(p, "]", 1);
-  p->depth_--;
-  return true;
-}
-
-static void *startmap(void *closure, const void *handler_data) {
-  upb_json_printer *p = closure;
-  CHK(putkey(closure, handler_data));
-  p->depth_++;
-  p->first_elem_[p->depth_] = true;
-  print_data(p, "{", 1);
-  return closure;
-}
-
-static bool endmap(void *closure, const void *handler_data) {
-  upb_json_printer *p = closure;
-  UPB_UNUSED(handler_data);
-  print_data(p, "}", 1);
-  p->depth_--;
-  return true;
-}
-
-static size_t putstr(void *closure, const void *handler_data, const char *str,
-                     size_t len, const upb_bufhandle *handle) {
-  upb_json_printer *p = closure;
-  UPB_UNUSED(handler_data);
-  UPB_UNUSED(handle);
-  putstring(p, str, len);
-  return len;
-}
-
-/* This has to Base64 encode the bytes, because JSON has no "bytes" type. */
-static size_t putbytes(void *closure, const void *handler_data, const char *str,
-                       size_t len, const upb_bufhandle *handle) {
-  upb_json_printer *p = closure;
-
-  /* This is the regular base64, not the "web-safe" version. */
-  static const char base64[] =
-      "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
-
-  /* Base64-encode. */
-  char data[16000];
-  const char *limit = data + sizeof(data);
-  const unsigned char *from = (const unsigned char*)str;
-  char *to = data;
-  size_t remaining = len;
-  size_t bytes;
-
-  UPB_UNUSED(handler_data);
-  UPB_UNUSED(handle);
-
-  while (remaining > 2) {
-    /* TODO(haberman): handle encoded lengths > sizeof(data) */
-    UPB_ASSERT_VAR(limit, (limit - to) >= 4);
-
-    to[0] = base64[from[0] >> 2];
-    to[1] = base64[((from[0] & 0x3) << 4) | (from[1] >> 4)];
-    to[2] = base64[((from[1] & 0xf) << 2) | (from[2] >> 6)];
-    to[3] = base64[from[2] & 0x3f];
-
-    remaining -= 3;
-    to += 4;
-    from += 3;
-  }
-
-  switch (remaining) {
-    case 2:
-      to[0] = base64[from[0] >> 2];
-      to[1] = base64[((from[0] & 0x3) << 4) | (from[1] >> 4)];
-      to[2] = base64[(from[1] & 0xf) << 2];
-      to[3] = '=';
-      to += 4;
-      from += 2;
-      break;
-    case 1:
-      to[0] = base64[from[0] >> 2];
-      to[1] = base64[((from[0] & 0x3) << 4)];
-      to[2] = '=';
-      to[3] = '=';
-      to += 4;
-      from += 1;
-      break;
-  }
-
-  bytes = to - data;
-  print_data(p, "\"", 1);
-  putstring(p, data, bytes);
-  print_data(p, "\"", 1);
-  return len;
-}
-
-static void *scalar_startstr(void *closure, const void *handler_data,
-                             size_t size_hint) {
-  upb_json_printer *p = closure;
-  UPB_UNUSED(handler_data);
-  UPB_UNUSED(size_hint);
-  CHK(putkey(closure, handler_data));
-  print_data(p, "\"", 1);
-  return p;
-}
-
-static size_t scalar_str(void *closure, const void *handler_data,
-                         const char *str, size_t len,
-                         const upb_bufhandle *handle) {
-  CHK(putstr(closure, handler_data, str, len, handle));
-  return len;
-}
-
-static bool scalar_endstr(void *closure, const void *handler_data) {
-  upb_json_printer *p = closure;
-  UPB_UNUSED(handler_data);
-  print_data(p, "\"", 1);
-  return true;
-}
-
-static void *repeated_startstr(void *closure, const void *handler_data,
-                               size_t size_hint) {
-  upb_json_printer *p = closure;
-  UPB_UNUSED(handler_data);
-  UPB_UNUSED(size_hint);
-  print_comma(p);
-  print_data(p, "\"", 1);
-  return p;
-}
-
-static size_t repeated_str(void *closure, const void *handler_data,
-                           const char *str, size_t len,
-                           const upb_bufhandle *handle) {
-  CHK(putstr(closure, handler_data, str, len, handle));
-  return len;
-}
-
-static bool repeated_endstr(void *closure, const void *handler_data) {
-  upb_json_printer *p = closure;
-  UPB_UNUSED(handler_data);
-  print_data(p, "\"", 1);
-  return true;
-}
-
-static void *mapkeyval_startstr(void *closure, const void *handler_data,
-                                size_t size_hint) {
-  upb_json_printer *p = closure;
-  UPB_UNUSED(handler_data);
-  UPB_UNUSED(size_hint);
-  print_data(p, "\"", 1);
-  return p;
-}
-
-static size_t mapkey_str(void *closure, const void *handler_data,
-                         const char *str, size_t len,
-                         const upb_bufhandle *handle) {
-  CHK(putstr(closure, handler_data, str, len, handle));
-  return len;
-}
-
-static bool mapkey_endstr(void *closure, const void *handler_data) {
-  upb_json_printer *p = closure;
-  UPB_UNUSED(handler_data);
-  print_data(p, "\":", 2);
-  return true;
-}
-
-static bool mapvalue_endstr(void *closure, const void *handler_data) {
-  upb_json_printer *p = closure;
-  UPB_UNUSED(handler_data);
-  print_data(p, "\"", 1);
-  return true;
-}
-
-static size_t scalar_bytes(void *closure, const void *handler_data,
-                           const char *str, size_t len,
-                           const upb_bufhandle *handle) {
-  CHK(putkey(closure, handler_data));
-  CHK(putbytes(closure, handler_data, str, len, handle));
-  return len;
-}
-
-static size_t repeated_bytes(void *closure, const void *handler_data,
-                             const char *str, size_t len,
-                             const upb_bufhandle *handle) {
-  upb_json_printer *p = closure;
-  print_comma(p);
-  CHK(putbytes(closure, handler_data, str, len, handle));
-  return len;
-}
-
-static size_t mapkey_bytes(void *closure, const void *handler_data,
-                           const char *str, size_t len,
-                           const upb_bufhandle *handle) {
-  upb_json_printer *p = closure;
-  CHK(putbytes(closure, handler_data, str, len, handle));
-  print_data(p, ":", 1);
-  return len;
-}
-
-static void set_enum_hd(upb_handlers *h,
-                        const upb_fielddef *f,
-                        upb_handlerattr *attr) {
-  EnumHandlerData *hd = malloc(sizeof(EnumHandlerData));
-  hd->enumdef = (const upb_enumdef *)upb_fielddef_subdef(f);
-  hd->keyname = newstrpc(h, f);
-  upb_handlers_addcleanup(h, hd, free);
-  upb_handlerattr_sethandlerdata(attr, hd);
-}
-
-/* Set up handlers for a mapentry submessage (i.e., an individual key/value pair
- * in a map).
- *
- * TODO: Handle missing key, missing value, out-of-order key/value, or repeated
- * key or value cases properly. The right way to do this is to allocate a
- * temporary structure at the start of a mapentry submessage, store key and
- * value data in it as key and value handlers are called, and then print the
- * key/value pair once at the end of the submessage. If we don't do this, we
- * should at least detect the case and throw an error. However, so far all of
- * our sources that emit mapentry messages do so canonically (with one key
- * field, and then one value field), so this is not a pressing concern at the
- * moment. */
-void printer_sethandlers_mapentry(const void *closure, upb_handlers *h) {
-  const upb_msgdef *md = upb_handlers_msgdef(h);
-
-  /* A mapentry message is printed simply as '"key": value'. Rather than
-   * special-case key and value for every type below, we just handle both
-   * fields explicitly here. */
-  const upb_fielddef* key_field = upb_msgdef_itof(md, UPB_MAPENTRY_KEY);
-  const upb_fielddef* value_field = upb_msgdef_itof(md, UPB_MAPENTRY_VALUE);
-
-  upb_handlerattr empty_attr = UPB_HANDLERATTR_INITIALIZER;
-
-  UPB_UNUSED(closure);
-
-  switch (upb_fielddef_type(key_field)) {
-    case UPB_TYPE_INT32:
-      upb_handlers_setint32(h, key_field, putmapkey_int32_t, &empty_attr);
-      break;
-    case UPB_TYPE_INT64:
-      upb_handlers_setint64(h, key_field, putmapkey_int64_t, &empty_attr);
-      break;
-    case UPB_TYPE_UINT32:
-      upb_handlers_setuint32(h, key_field, putmapkey_uint32_t, &empty_attr);
-      break;
-    case UPB_TYPE_UINT64:
-      upb_handlers_setuint64(h, key_field, putmapkey_uint64_t, &empty_attr);
-      break;
-    case UPB_TYPE_BOOL:
-      upb_handlers_setbool(h, key_field, putmapkey_bool, &empty_attr);
-      break;
-    case UPB_TYPE_STRING:
-      upb_handlers_setstartstr(h, key_field, mapkeyval_startstr, &empty_attr);
-      upb_handlers_setstring(h, key_field, mapkey_str, &empty_attr);
-      upb_handlers_setendstr(h, key_field, mapkey_endstr, &empty_attr);
-      break;
-    case UPB_TYPE_BYTES:
-      upb_handlers_setstring(h, key_field, mapkey_bytes, &empty_attr);
-      break;
-    default:
-      assert(false);
-      break;
-  }
-
-  switch (upb_fielddef_type(value_field)) {
-    case UPB_TYPE_INT32:
-      upb_handlers_setint32(h, value_field, putint32_t, &empty_attr);
-      break;
-    case UPB_TYPE_INT64:
-      upb_handlers_setint64(h, value_field, putint64_t, &empty_attr);
-      break;
-    case UPB_TYPE_UINT32:
-      upb_handlers_setuint32(h, value_field, putuint32_t, &empty_attr);
-      break;
-    case UPB_TYPE_UINT64:
-      upb_handlers_setuint64(h, value_field, putuint64_t, &empty_attr);
-      break;
-    case UPB_TYPE_BOOL:
-      upb_handlers_setbool(h, value_field, putbool, &empty_attr);
-      break;
-    case UPB_TYPE_FLOAT:
-      upb_handlers_setfloat(h, value_field, putfloat, &empty_attr);
-      break;
-    case UPB_TYPE_DOUBLE:
-      upb_handlers_setdouble(h, value_field, putdouble, &empty_attr);
-      break;
-    case UPB_TYPE_STRING:
-      upb_handlers_setstartstr(h, value_field, mapkeyval_startstr, &empty_attr);
-      upb_handlers_setstring(h, value_field, putstr, &empty_attr);
-      upb_handlers_setendstr(h, value_field, mapvalue_endstr, &empty_attr);
-      break;
-    case UPB_TYPE_BYTES:
-      upb_handlers_setstring(h, value_field, putbytes, &empty_attr);
-      break;
-    case UPB_TYPE_ENUM: {
-      upb_handlerattr enum_attr = UPB_HANDLERATTR_INITIALIZER;
-      set_enum_hd(h, value_field, &enum_attr);
-      upb_handlers_setint32(h, value_field, mapvalue_enum, &enum_attr);
-      upb_handlerattr_uninit(&enum_attr);
-      break;
-    }
-    case UPB_TYPE_MESSAGE:
-      /* No handler necessary -- the submsg handlers will print the message
-       * as appropriate. */
-      break;
-  }
-
-  upb_handlerattr_uninit(&empty_attr);
-}
-
-void printer_sethandlers(const void *closure, upb_handlers *h) {
-  const upb_msgdef *md = upb_handlers_msgdef(h);
-  bool is_mapentry = upb_msgdef_mapentry(md);
-  upb_handlerattr empty_attr = UPB_HANDLERATTR_INITIALIZER;
-  upb_msg_field_iter i;
-
-  UPB_UNUSED(closure);
-
-  if (is_mapentry) {
-    /* mapentry messages are sufficiently different that we handle them
-     * separately. */
-    printer_sethandlers_mapentry(closure, h);
-    return;
-  }
-
-  upb_handlers_setstartmsg(h, printer_startmsg, &empty_attr);
-  upb_handlers_setendmsg(h, printer_endmsg, &empty_attr);
-
-#define TYPE(type, name, ctype)                                               \
-  case type:                                                                  \
-    if (upb_fielddef_isseq(f)) {                                              \
-      upb_handlers_set##name(h, f, repeated_##ctype, &empty_attr);            \
-    } else {                                                                  \
-      upb_handlers_set##name(h, f, scalar_##ctype, &name_attr);               \
-    }                                                                         \
-    break;
-
-  upb_msg_field_begin(&i, md);
-  for(; !upb_msg_field_done(&i); upb_msg_field_next(&i)) {
-    const upb_fielddef *f = upb_msg_iter_field(&i);
-
-    upb_handlerattr name_attr = UPB_HANDLERATTR_INITIALIZER;
-    upb_handlerattr_sethandlerdata(&name_attr, newstrpc(h, f));
-
-    if (upb_fielddef_ismap(f)) {
-      upb_handlers_setstartseq(h, f, startmap, &name_attr);
-      upb_handlers_setendseq(h, f, endmap, &name_attr);
-    } else if (upb_fielddef_isseq(f)) {
-      upb_handlers_setstartseq(h, f, startseq, &name_attr);
-      upb_handlers_setendseq(h, f, endseq, &empty_attr);
-    }
-
-    switch (upb_fielddef_type(f)) {
-      TYPE(UPB_TYPE_FLOAT,  float,  float);
-      TYPE(UPB_TYPE_DOUBLE, double, double);
-      TYPE(UPB_TYPE_BOOL,   bool,   bool);
-      TYPE(UPB_TYPE_INT32,  int32,  int32_t);
-      TYPE(UPB_TYPE_UINT32, uint32, uint32_t);
-      TYPE(UPB_TYPE_INT64,  int64,  int64_t);
-      TYPE(UPB_TYPE_UINT64, uint64, uint64_t);
-      case UPB_TYPE_ENUM: {
-        /* For now, we always emit symbolic names for enums. We may want an
-         * option later to control this behavior, but we will wait for a real
-         * need first. */
-        upb_handlerattr enum_attr = UPB_HANDLERATTR_INITIALIZER;
-        set_enum_hd(h, f, &enum_attr);
-
-        if (upb_fielddef_isseq(f)) {
-          upb_handlers_setint32(h, f, repeated_enum, &enum_attr);
-        } else {
-          upb_handlers_setint32(h, f, scalar_enum, &enum_attr);
-        }
-
-        upb_handlerattr_uninit(&enum_attr);
-        break;
-      }
-      case UPB_TYPE_STRING:
-        if (upb_fielddef_isseq(f)) {
-          upb_handlers_setstartstr(h, f, repeated_startstr, &empty_attr);
-          upb_handlers_setstring(h, f, repeated_str, &empty_attr);
-          upb_handlers_setendstr(h, f, repeated_endstr, &empty_attr);
-        } else {
-          upb_handlers_setstartstr(h, f, scalar_startstr, &name_attr);
-          upb_handlers_setstring(h, f, scalar_str, &empty_attr);
-          upb_handlers_setendstr(h, f, scalar_endstr, &empty_attr);
-        }
-        break;
-      case UPB_TYPE_BYTES:
-        /* XXX: this doesn't support strings that span buffers yet. The base64
-         * encoder will need to be made resumable for this to work properly. */
-        if (upb_fielddef_isseq(f)) {
-          upb_handlers_setstring(h, f, repeated_bytes, &empty_attr);
-        } else {
-          upb_handlers_setstring(h, f, scalar_bytes, &name_attr);
-        }
-        break;
-      case UPB_TYPE_MESSAGE:
-        if (upb_fielddef_isseq(f)) {
-          upb_handlers_setstartsubmsg(h, f, repeated_startsubmsg, &name_attr);
-        } else {
-          upb_handlers_setstartsubmsg(h, f, scalar_startsubmsg, &name_attr);
-        }
-        break;
-    }
-
-    upb_handlerattr_uninit(&name_attr);
-  }
-
-  upb_handlerattr_uninit(&empty_attr);
-#undef TYPE
-}
-
-static void json_printer_reset(upb_json_printer *p) {
-  p->depth_ = 0;
-}
-
-
-/* Public API *****************************************************************/
-
-upb_json_printer *upb_json_printer_create(upb_env *e, const upb_handlers *h,
-                                          upb_bytessink *output) {
-#ifndef NDEBUG
-  size_t size_before = upb_env_bytesallocated(e);
-#endif
-
-  upb_json_printer *p = upb_env_malloc(e, sizeof(upb_json_printer));
-  if (!p) return NULL;
-
-  p->output_ = output;
-  json_printer_reset(p);
-  upb_sink_reset(&p->input_, h, p);
-
-  /* If this fails, increase the value in printer.h. */
-  assert(upb_env_bytesallocated(e) - size_before <= UPB_JSON_PRINTER_SIZE);
-  return p;
-}
-
-upb_sink *upb_json_printer_input(upb_json_printer *p) {
-  return &p->input_;
-}
-
-const upb_handlers *upb_json_printer_newhandlers(const upb_msgdef *md,
-                                                 const void *owner) {
-  return upb_handlers_newfrozen(md, owner, printer_sethandlers, NULL);
-}