Reland "Move functions from handles.cc to where they belong."

src/objects.cc

Index: src/objects.cc
diff --git a/src/objects.cc b/src/objects.cc
index 241524e3d3cab3bfd99b3a45fa4d1db54da008c6..2a54d3cb5ec18c0ee3fe0c055e0c64809c7d14a3 100644
--- a/src/objects.cc
+++ b/src/objects.cc
@@ -49,6 +49,7 @@
 #include "macro-assembler.h"
 #include "mark-compact.h"
 #include "safepoint-table.h"
+#include "string-search.h"
 #include "string-stream.h"
 #include "utils.h"
 
@@ -6239,6 +6240,247 @@ void JSObject::LookupCallbackProperty(Name* name, LookupResult* result) {
 }
 
 
+static bool ContainsOnlyValidKeys(Handle<FixedArray> array) {
+  int len = array->length();
+  for (int i = 0; i < len; i++) {
+    Object* e = array->get(i);
+    if (!(e->IsString() || e->IsNumber())) return false;
+  }
+  return true;
+}
+
+
+static Handle<FixedArray> ReduceFixedArrayTo(
+    Handle<FixedArray> array, int length) {
+  ASSERT(array->length() >= length);
+  if (array->length() == length) return array;
+
+  Handle<FixedArray> new_array =
+      array->GetIsolate()->factory()->NewFixedArray(length);
+  for (int i = 0; i < length; ++i) new_array->set(i, array->get(i));
+  return new_array;
+}
+
+
+static Handle<FixedArray> GetEnumPropertyKeys(Handle<JSObject> object,
+                                              bool cache_result) {
+  Isolate* isolate = object->GetIsolate();
+  if (object->HasFastProperties()) {
+    int own_property_count = object->map()->EnumLength();
+    // If the enum length of the given map is set to kInvalidEnumCache, this
+    // means that the map itself has never used the present enum cache. The
+    // first step to using the cache is to set the enum length of the map by
+    // counting the number of own descriptors that are not DONT_ENUM or
+    // SYMBOLIC.
+    if (own_property_count == kInvalidEnumCacheSentinel) {
+      own_property_count = object->map()->NumberOfDescribedProperties(
+          OWN_DESCRIPTORS, DONT_SHOW);
+    } else {
+      ASSERT(own_property_count == object->map()->NumberOfDescribedProperties(
+          OWN_DESCRIPTORS, DONT_SHOW));
+    }
+
+    if (object->map()->instance_descriptors()->HasEnumCache()) {
+      DescriptorArray* desc = object->map()->instance_descriptors();
+      Handle<FixedArray> keys(desc->GetEnumCache(), isolate);
+
+      // In case the number of properties required in the enum are actually
+      // present, we can reuse the enum cache. Otherwise, this means that the
+      // enum cache was generated for a previous (smaller) version of the
+      // Descriptor Array. In that case we regenerate the enum cache.
+      if (own_property_count <= keys->length()) {
+        if (cache_result) object->map()->SetEnumLength(own_property_count);
+        isolate->counters()->enum_cache_hits()->Increment();
+        return ReduceFixedArrayTo(keys, own_property_count);
+      }
+    }
+
+    Handle<Map> map(object->map());
+
+    if (map->instance_descriptors()->IsEmpty()) {
+      isolate->counters()->enum_cache_hits()->Increment();
+      if (cache_result) map->SetEnumLength(0);
+      return isolate->factory()->empty_fixed_array();
+    }
+
+    isolate->counters()->enum_cache_misses()->Increment();
+
+    Handle<FixedArray> storage = isolate->factory()->NewFixedArray(
+        own_property_count);
+    Handle<FixedArray> indices = isolate->factory()->NewFixedArray(
+        own_property_count);
+
+    Handle<DescriptorArray> descs =
+        Handle<DescriptorArray>(object->map()->instance_descriptors(), isolate);
+
+    int size = map->NumberOfOwnDescriptors();
+    int index = 0;
+
+    for (int i = 0; i < size; i++) {
+      PropertyDetails details = descs->GetDetails(i);
+      Object* key = descs->GetKey(i);
+      if (!(details.IsDontEnum() || key->IsSymbol())) {
+        storage->set(index, key);
+        if (!indices.is_null()) {
+          if (details.type() != FIELD) {
+            indices = Handle<FixedArray>();
+          } else {
+            int field_index = descs->GetFieldIndex(i);
+            if (field_index >= map->inobject_properties()) {
+              field_index = -(field_index - map->inobject_properties() + 1);
+            }
+            field_index = field_index << 1;
+            if (details.representation().IsDouble()) {
+              field_index |= 1;
+            }
+            indices->set(index, Smi::FromInt(field_index));
+          }
+        }
+        index++;
+      }
+    }
+    ASSERT(index == storage->length());
+
+    Handle<FixedArray> bridge_storage =
+        isolate->factory()->NewFixedArray(
+            DescriptorArray::kEnumCacheBridgeLength);
+    DescriptorArray* desc = object->map()->instance_descriptors();
+    desc->SetEnumCache(*bridge_storage,
+                       *storage,
+                       indices.is_null() ? Object::cast(Smi::FromInt(0))
+                                         : Object::cast(*indices));
+    if (cache_result) {
+      object->map()->SetEnumLength(own_property_count);
+    }
+    return storage;
+  } else {
+    Handle<NameDictionary> dictionary(object->property_dictionary());
+    int length = dictionary->NumberOfEnumElements();
+    if (length == 0) {
+      return Handle<FixedArray>(isolate->heap()->empty_fixed_array());
+    }
+    Handle<FixedArray> storage = isolate->factory()->NewFixedArray(length);
+    dictionary->CopyEnumKeysTo(*storage);
+    return storage;
+  }
+}
+
+
+MaybeHandle<FixedArray> JSReceiver::GetKeys(Handle<JSReceiver> object,
+                                            KeyCollectionType type) {
+  USE(ContainsOnlyValidKeys);
+  Isolate* isolate = object->GetIsolate();
+  Handle<FixedArray> content = isolate->factory()->empty_fixed_array();
+  Handle<JSObject> arguments_boilerplate = Handle<JSObject>(
+      isolate->context()->native_context()->sloppy_arguments_boilerplate(),
+      isolate);
+  Handle<JSFunction> arguments_function = Handle<JSFunction>(
+      JSFunction::cast(arguments_boilerplate->map()->constructor()),
+      isolate);
+
+  // Only collect keys if access is permitted.
+  for (Handle<Object> p = object;
+       *p != isolate->heap()->null_value();
+       p = Handle<Object>(p->GetPrototype(isolate), isolate)) {
+    if (p->IsJSProxy()) {
+      Handle<JSProxy> proxy(JSProxy::cast(*p), isolate);
+      Handle<Object> args[] = { proxy };
+      Handle<Object> names;
+      ASSIGN_RETURN_ON_EXCEPTION(
+          isolate, names,
+          Execution::Call(isolate,
+                          isolate->proxy_enumerate(),
+                          object,
+                          ARRAY_SIZE(args),
+                          args),
+          FixedArray);
+      ASSIGN_RETURN_ON_EXCEPTION(
+          isolate, content,
+          FixedArray::AddKeysFromJSArray(
+              content, Handle<JSArray>::cast(names)),
+          FixedArray);
+      break;
+    }
+
+    Handle<JSObject> current(JSObject::cast(*p), isolate);
+
+    // Check access rights if required.
+    if (current->IsAccessCheckNeeded() &&
+        !isolate->MayNamedAccess(
+            current, isolate->factory()->undefined_value(), v8::ACCESS_KEYS)) {
+      isolate->ReportFailedAccessCheck(current, v8::ACCESS_KEYS);
+      RETURN_EXCEPTION_IF_SCHEDULED_EXCEPTION(isolate, FixedArray);
+      break;
+    }
+
+    // Compute the element keys.
+    Handle<FixedArray> element_keys =
+        isolate->factory()->NewFixedArray(current->NumberOfEnumElements());
+    current->GetEnumElementKeys(*element_keys);
+    ASSIGN_RETURN_ON_EXCEPTION(
+        isolate, content,
+        FixedArray::UnionOfKeys(content, element_keys),
+        FixedArray);
+    ASSERT(ContainsOnlyValidKeys(content));
+
+    // Add the element keys from the interceptor.
+    if (current->HasIndexedInterceptor()) {
+      Handle<JSArray> result;
+      if (JSObject::GetKeysForIndexedInterceptor(
+              current, object).ToHandle(&result)) {
+        ASSIGN_RETURN_ON_EXCEPTION(
+            isolate, content,
+            FixedArray::AddKeysFromJSArray(content, result),
+            FixedArray);
+      }
+      ASSERT(ContainsOnlyValidKeys(content));
+    }
+
+    // We can cache the computed property keys if access checks are
+    // not needed and no interceptors are involved.
+    //
+    // We do not use the cache if the object has elements and
+    // therefore it does not make sense to cache the property names
+    // for arguments objects.  Arguments objects will always have
+    // elements.
+    // Wrapped strings have elements, but don't have an elements
+    // array or dictionary.  So the fast inline test for whether to
+    // use the cache says yes, so we should not create a cache.
+    bool cache_enum_keys =
+        ((current->map()->constructor() != *arguments_function) &&
+         !current->IsJSValue() &&
+         !current->IsAccessCheckNeeded() &&
+         !current->HasNamedInterceptor() &&
+         !current->HasIndexedInterceptor());
+    // Compute the property keys and cache them if possible.
+    ASSIGN_RETURN_ON_EXCEPTION(
+        isolate, content,
+        FixedArray::UnionOfKeys(
+            content, GetEnumPropertyKeys(current, cache_enum_keys)),
+        FixedArray);
+    ASSERT(ContainsOnlyValidKeys(content));
+
+    // Add the property keys from the interceptor.
+    if (current->HasNamedInterceptor()) {
+      Handle<JSArray> result;
+      if (JSObject::GetKeysForNamedInterceptor(
+              current, object).ToHandle(&result)) {
+        ASSIGN_RETURN_ON_EXCEPTION(
+            isolate, content,
+            FixedArray::AddKeysFromJSArray(content, result),
+            FixedArray);
+      }
+      ASSERT(ContainsOnlyValidKeys(content));
+    }
+
+    // If we only want local properties we bail out after the first
+    // iteration.
+    if (type == LOCAL_ONLY) break;
+  }
+  return content;
+}
+
+
 // Try to update an accessor in an elements dictionary. Return true if the
 // update succeeded, and false otherwise.
 static bool UpdateGetterSetterInDictionary(
@@ -8901,6 +9143,64 @@ void String::WriteToFlat(String* src,
 }
 
 
+
+template <typename SourceChar>
+static void CalculateLineEndsImpl(Isolate* isolate,
+                                  List<int>* line_ends,
+                                  Vector<const SourceChar> src,
+                                  bool include_ending_line) {
+  const int src_len = src.length();
+  StringSearch<uint8_t, SourceChar> search(isolate, STATIC_ASCII_VECTOR("\n"));
+
+  // Find and record line ends.
+  int position = 0;
+  while (position != -1 && position < src_len) {
+    position = search.Search(src, position);
+    if (position != -1) {
+      line_ends->Add(position);
+      position++;
+    } else if (include_ending_line) {
+      // Even if the last line misses a line end, it is counted.
+      line_ends->Add(src_len);
+      return;
+    }
+  }
+}
+
+
+Handle<FixedArray> String::CalculateLineEnds(Handle<String> src,
+                                             bool include_ending_line) {
+  src = Flatten(src);
+  // Rough estimate of line count based on a roughly estimated average
+  // length of (unpacked) code.
+  int line_count_estimate = src->length() >> 4;
+  List<int> line_ends(line_count_estimate);
+  Isolate* isolate = src->GetIsolate();
+  { DisallowHeapAllocation no_allocation;  // ensure vectors stay valid.
+    // Dispatch on type of strings.
+    String::FlatContent content = src->GetFlatContent();
+    ASSERT(content.IsFlat());
+    if (content.IsAscii()) {
+      CalculateLineEndsImpl(isolate,
+                            &line_ends,
+                            content.ToOneByteVector(),
+                            include_ending_line);
+    } else {
+      CalculateLineEndsImpl(isolate,
+                            &line_ends,
+                            content.ToUC16Vector(),
+                            include_ending_line);
+    }
+  }
+  int line_count = line_ends.length();
+  Handle<FixedArray> array = isolate->factory()->NewFixedArray(line_count);
+  for (int i = 0; i < line_count; i++) {
+    array->set(i, Smi::FromInt(line_ends[i]));
+  }
+  return array;
+}
+
+
 // Compares the contents of two strings by reading and comparing
 // int-sized blocks of characters.
 template <typename Char>
@@ -10110,6 +10410,161 @@ MaybeObject* Oddball::Initialize(Heap* heap,
 }
 
 
+void Script::InitLineEnds(Handle<Script> script) {
+  if (!script->line_ends()->IsUndefined()) return;
+
+  Isolate* isolate = script->GetIsolate();
+
+  if (!script->source()->IsString()) {
+    ASSERT(script->source()->IsUndefined());
+    Handle<FixedArray> empty = isolate->factory()->NewFixedArray(0);
+    script->set_line_ends(*empty);
+    ASSERT(script->line_ends()->IsFixedArray());
+    return;
+  }
+
+  Handle<String> src(String::cast(script->source()), isolate);
+
+  Handle<FixedArray> array = String::CalculateLineEnds(src, true);
+
+  if (*array != isolate->heap()->empty_fixed_array()) {
+    array->set_map(isolate->heap()->fixed_cow_array_map());
+  }
+
+  script->set_line_ends(*array);
+  ASSERT(script->line_ends()->IsFixedArray());
+}
+
+
+int Script::GetColumnNumber(Handle<Script> script, int code_pos) {
+  int line_number = GetLineNumber(script, code_pos);
+  if (line_number == -1) return -1;
+
+  DisallowHeapAllocation no_allocation;
+  FixedArray* line_ends_array = FixedArray::cast(script->line_ends());
+  line_number = line_number - script->line_offset()->value();
+  if (line_number == 0) return code_pos + script->column_offset()->value();
+  int prev_line_end_pos =
+      Smi::cast(line_ends_array->get(line_number - 1))->value();
+  return code_pos - (prev_line_end_pos + 1);
+}
+
+
+int Script::GetLineNumberWithArray(int code_pos) {
+  DisallowHeapAllocation no_allocation;
+  ASSERT(line_ends()->IsFixedArray());
+  FixedArray* line_ends_array = FixedArray::cast(line_ends());
+  int line_ends_len = line_ends_array->length();
+  if (line_ends_len == 0) return -1;
+
+  if ((Smi::cast(line_ends_array->get(0)))->value() >= code_pos) {
+    return line_offset()->value();
+  }
+
+  int left = 0;
+  int right = line_ends_len;
+  while (int half = (right - left) / 2) {
+    if ((Smi::cast(line_ends_array->get(left + half)))->value() > code_pos) {
+      right -= half;
+    } else {
+      left += half;
+    }
+  }
+  return right + line_offset()->value();
+}
+
+
+int Script::GetLineNumber(Handle<Script> script, int code_pos) {
+  InitLineEnds(script);
+  return script->GetLineNumberWithArray(code_pos);
+}
+
+
+int Script::GetLineNumber(int code_pos) {
+  DisallowHeapAllocation no_allocation;
+  if (!line_ends()->IsUndefined()) return GetLineNumberWithArray(code_pos);
+
+  // Slow mode: we do not have line_ends. We have to iterate through source.
+  if (!source()->IsString()) return -1;
+
+  String* source_string = String::cast(source());
+  int line = 0;
+  int len = source_string->length();
+  for (int pos = 0; pos < len; pos++) {
+    if (pos == code_pos) break;
+    if (source_string->Get(pos) == '\n') line++;
+  }
+  return line;
+}
+
+
+Handle<Object> Script::GetNameOrSourceURL(Handle<Script> script) {
+  Isolate* isolate = script->GetIsolate();
+  Handle<String> name_or_source_url_key =
+      isolate->factory()->InternalizeOneByteString(
+          STATIC_ASCII_VECTOR("nameOrSourceURL"));
+  Handle<JSObject> script_wrapper = Script::GetWrapper(script);
+  Handle<Object> property = Object::GetProperty(
+      script_wrapper, name_or_source_url_key).ToHandleChecked();
+  ASSERT(property->IsJSFunction());
+  Handle<JSFunction> method = Handle<JSFunction>::cast(property);
+  Handle<Object> result;
+  // Do not check against pending exception, since this function may be called
+  // when an exception has already been pending.
+  if (!Execution::TryCall(method, script_wrapper, 0, NULL).ToHandle(&result)) {
+    return isolate->factory()->undefined_value();
+  }
+  return result;
+}
+
+
+// Wrappers for scripts are kept alive and cached in weak global
+// handles referred from foreign objects held by the scripts as long as
+// they are used. When they are not used anymore, the garbage
+// collector will call the weak callback on the global handle
+// associated with the wrapper and get rid of both the wrapper and the
+// handle.
+static void ClearWrapperCache(
+    const v8::WeakCallbackData<v8::Value, void>& data) {
+  Object** location = reinterpret_cast<Object**>(data.GetParameter());
+  JSValue* wrapper = JSValue::cast(*location);
+  Foreign* foreign = Script::cast(wrapper->value())->wrapper();
+  ASSERT_EQ(foreign->foreign_address(), reinterpret_cast<Address>(location));
+  foreign->set_foreign_address(0);
+  GlobalHandles::Destroy(location);
+  Isolate* isolate = reinterpret_cast<Isolate*>(data.GetIsolate());
+  isolate->counters()->script_wrappers()->Decrement();
+}
+
+
+Handle<JSObject> Script::GetWrapper(Handle<Script> script) {
+  if (script->wrapper()->foreign_address() != NULL) {
+    // Return a handle for the existing script wrapper from the cache.
+    return Handle<JSValue>(
+        *reinterpret_cast<JSValue**>(script->wrapper()->foreign_address()));
+  }
+  Isolate* isolate = script->GetIsolate();
+  // Construct a new script wrapper.
+  isolate->counters()->script_wrappers()->Increment();
+  Handle<JSFunction> constructor = isolate->script_function();
+  Handle<JSValue> result =
+      Handle<JSValue>::cast(isolate->factory()->NewJSObject(constructor));
+
+  result->set_value(*script);
+
+  // Create a new weak global handle and use it to cache the wrapper
+  // for future use. The cache will automatically be cleared by the
+  // garbage collector when it is not used anymore.
+  Handle<Object> handle = isolate->global_handles()->Create(*result);
+  GlobalHandles::MakeWeak(handle.location(),
+                          reinterpret_cast<void*>(handle.location()),
+                          &ClearWrapperCache);
+  script->wrapper()->set_foreign_address(
+      reinterpret_cast<Address>(handle.location()));
+  return result;
+}
+
+
 String* SharedFunctionInfo::DebugName() {
   Object* n = name();
   if (!n->IsString() || String::cast(n)->length() == 0) return inferred_name();
@@ -13437,6 +13892,55 @@ MaybeHandle<Object> JSObject::GetPropertyWithInterceptor(
 }
 
 
+// Compute the property keys from the interceptor.
+// TODO(rossberg): support symbols in API, and filter here if needed.
+MaybeHandle<JSArray> JSObject::GetKeysForNamedInterceptor(
+    Handle<JSObject> object, Handle<JSReceiver> receiver) {
+  Isolate* isolate = receiver->GetIsolate();
+  Handle<InterceptorInfo> interceptor(object->GetNamedInterceptor());
+  PropertyCallbackArguments
+      args(isolate, interceptor->data(), *receiver, *object);
+  v8::Handle<v8::Array> result;
+  if (!interceptor->enumerator()->IsUndefined()) {
+    v8::NamedPropertyEnumeratorCallback enum_fun =
+        v8::ToCData<v8::NamedPropertyEnumeratorCallback>(
+            interceptor->enumerator());
+    LOG(isolate, ApiObjectAccess("interceptor-named-enum", *object));
+    result = args.Call(enum_fun);
+  }
+  if (result.IsEmpty()) return MaybeHandle<JSArray>();
+#if ENABLE_EXTRA_CHECKS
+  CHECK(v8::Utils::OpenHandle(*result)->IsJSObject());
+#endif
+  // Rebox before returning.
+  return handle(*v8::Utils::OpenHandle(*result), isolate);
+}
+
+
+// Compute the element keys from the interceptor.
+MaybeHandle<JSArray> JSObject::GetKeysForIndexedInterceptor(
+    Handle<JSObject> object, Handle<JSReceiver> receiver) {
+  Isolate* isolate = receiver->GetIsolate();
+  Handle<InterceptorInfo> interceptor(object->GetIndexedInterceptor());
+  PropertyCallbackArguments
+      args(isolate, interceptor->data(), *receiver, *object);
+  v8::Handle<v8::Array> result;
+  if (!interceptor->enumerator()->IsUndefined()) {
+    v8::IndexedPropertyEnumeratorCallback enum_fun =
+        v8::ToCData<v8::IndexedPropertyEnumeratorCallback>(
+            interceptor->enumerator());
+    LOG(isolate, ApiObjectAccess("interceptor-indexed-enum", *object));
+    result = args.Call(enum_fun);
+  }
+  if (result.IsEmpty()) return MaybeHandle<JSArray>();
+#if ENABLE_EXTRA_CHECKS
+  CHECK(v8::Utils::OpenHandle(*result)->IsJSObject());
+#endif
+  // Rebox before returning.
+  return handle(*v8::Utils::OpenHandle(*result), isolate);
+}
+
+
 bool JSObject::HasRealNamedProperty(Handle<JSObject> object,
                                     Handle<Name> key) {
   Isolate* isolate = object->GetIsolate();