| Index: third_party/lua/src/ltable.c
|
| diff --git a/third_party/lua/src/ltable.c b/third_party/lua/src/ltable.c
|
| new file mode 100644
|
| index 0000000000000000000000000000000000000000..420391fc745d7da021965d2774957eaf22c794b8
|
| --- /dev/null
|
| +++ b/third_party/lua/src/ltable.c
|
| @@ -0,0 +1,588 @@
|
| +/*
|
| +** $Id: ltable.c,v 2.72 2012/09/11 19:37:16 roberto Exp $
|
| +** Lua tables (hash)
|
| +** See Copyright Notice in lua.h
|
| +*/
|
| +
|
| +
|
| +/*
|
| +** Implementation of tables (aka arrays, objects, or hash tables).
|
| +** Tables keep its elements in two parts: an array part and a hash part.
|
| +** Non-negative integer keys are all candidates to be kept in the array
|
| +** part. The actual size of the array is the largest `n' such that at
|
| +** least half the slots between 0 and n are in use.
|
| +** Hash uses a mix of chained scatter table with Brent's variation.
|
| +** A main invariant of these tables is that, if an element is not
|
| +** in its main position (i.e. the `original' position that its hash gives
|
| +** to it), then the colliding element is in its own main position.
|
| +** Hence even when the load factor reaches 100%, performance remains good.
|
| +*/
|
| +
|
| +#include <string.h>
|
| +
|
| +#define ltable_c
|
| +#define LUA_CORE
|
| +
|
| +#include "lua.h"
|
| +
|
| +#include "ldebug.h"
|
| +#include "ldo.h"
|
| +#include "lgc.h"
|
| +#include "lmem.h"
|
| +#include "lobject.h"
|
| +#include "lstate.h"
|
| +#include "lstring.h"
|
| +#include "ltable.h"
|
| +#include "lvm.h"
|
| +
|
| +
|
| +/*
|
| +** max size of array part is 2^MAXBITS
|
| +*/
|
| +#if LUAI_BITSINT >= 32
|
| +#define MAXBITS 30
|
| +#else
|
| +#define MAXBITS (LUAI_BITSINT-2)
|
| +#endif
|
| +
|
| +#define MAXASIZE (1 << MAXBITS)
|
| +
|
| +
|
| +#define hashpow2(t,n) (gnode(t, lmod((n), sizenode(t))))
|
| +
|
| +#define hashstr(t,str) hashpow2(t, (str)->tsv.hash)
|
| +#define hashboolean(t,p) hashpow2(t, p)
|
| +
|
| +
|
| +/*
|
| +** for some types, it is better to avoid modulus by power of 2, as
|
| +** they tend to have many 2 factors.
|
| +*/
|
| +#define hashmod(t,n) (gnode(t, ((n) % ((sizenode(t)-1)|1))))
|
| +
|
| +
|
| +#define hashpointer(t,p) hashmod(t, IntPoint(p))
|
| +
|
| +
|
| +#define dummynode (&dummynode_)
|
| +
|
| +#define isdummy(n) ((n) == dummynode)
|
| +
|
| +static const Node dummynode_ = {
|
| + {NILCONSTANT}, /* value */
|
| + {{NILCONSTANT, NULL}} /* key */
|
| +};
|
| +
|
| +
|
| +/*
|
| +** hash for lua_Numbers
|
| +*/
|
| +static Node *hashnum (const Table *t, lua_Number n) {
|
| + int i;
|
| + luai_hashnum(i, n);
|
| + if (i < 0) {
|
| + if (cast(unsigned int, i) == 0u - i) /* use unsigned to avoid overflows */
|
| + i = 0; /* handle INT_MIN */
|
| + i = -i; /* must be a positive value */
|
| + }
|
| + return hashmod(t, i);
|
| +}
|
| +
|
| +
|
| +
|
| +/*
|
| +** returns the `main' position of an element in a table (that is, the index
|
| +** of its hash value)
|
| +*/
|
| +static Node *mainposition (const Table *t, const TValue *key) {
|
| + switch (ttype(key)) {
|
| + case LUA_TNUMBER:
|
| + return hashnum(t, nvalue(key));
|
| + case LUA_TLNGSTR: {
|
| + TString *s = rawtsvalue(key);
|
| + if (s->tsv.extra == 0) { /* no hash? */
|
| + s->tsv.hash = luaS_hash(getstr(s), s->tsv.len, s->tsv.hash);
|
| + s->tsv.extra = 1; /* now it has its hash */
|
| + }
|
| + return hashstr(t, rawtsvalue(key));
|
| + }
|
| + case LUA_TSHRSTR:
|
| + return hashstr(t, rawtsvalue(key));
|
| + case LUA_TBOOLEAN:
|
| + return hashboolean(t, bvalue(key));
|
| + case LUA_TLIGHTUSERDATA:
|
| + return hashpointer(t, pvalue(key));
|
| + case LUA_TLCF:
|
| + return hashpointer(t, fvalue(key));
|
| + default:
|
| + return hashpointer(t, gcvalue(key));
|
| + }
|
| +}
|
| +
|
| +
|
| +/*
|
| +** returns the index for `key' if `key' is an appropriate key to live in
|
| +** the array part of the table, -1 otherwise.
|
| +*/
|
| +static int arrayindex (const TValue *key) {
|
| + if (ttisnumber(key)) {
|
| + lua_Number n = nvalue(key);
|
| + int k;
|
| + lua_number2int(k, n);
|
| + if (luai_numeq(cast_num(k), n))
|
| + return k;
|
| + }
|
| + return -1; /* `key' did not match some condition */
|
| +}
|
| +
|
| +
|
| +/*
|
| +** returns the index of a `key' for table traversals. First goes all
|
| +** elements in the array part, then elements in the hash part. The
|
| +** beginning of a traversal is signaled by -1.
|
| +*/
|
| +static int findindex (lua_State *L, Table *t, StkId key) {
|
| + int i;
|
| + if (ttisnil(key)) return -1; /* first iteration */
|
| + i = arrayindex(key);
|
| + if (0 < i && i <= t->sizearray) /* is `key' inside array part? */
|
| + return i-1; /* yes; that's the index (corrected to C) */
|
| + else {
|
| + Node *n = mainposition(t, key);
|
| + for (;;) { /* check whether `key' is somewhere in the chain */
|
| + /* key may be dead already, but it is ok to use it in `next' */
|
| + if (luaV_rawequalobj(gkey(n), key) ||
|
| + (ttisdeadkey(gkey(n)) && iscollectable(key) &&
|
| + deadvalue(gkey(n)) == gcvalue(key))) {
|
| + i = cast_int(n - gnode(t, 0)); /* key index in hash table */
|
| + /* hash elements are numbered after array ones */
|
| + return i + t->sizearray;
|
| + }
|
| + else n = gnext(n);
|
| + if (n == NULL)
|
| + luaG_runerror(L, "invalid key to " LUA_QL("next")); /* key not found */
|
| + }
|
| + }
|
| +}
|
| +
|
| +
|
| +int luaH_next (lua_State *L, Table *t, StkId key) {
|
| + int i = findindex(L, t, key); /* find original element */
|
| + for (i++; i < t->sizearray; i++) { /* try first array part */
|
| + if (!ttisnil(&t->array[i])) { /* a non-nil value? */
|
| + setnvalue(key, cast_num(i+1));
|
| + setobj2s(L, key+1, &t->array[i]);
|
| + return 1;
|
| + }
|
| + }
|
| + for (i -= t->sizearray; i < sizenode(t); i++) { /* then hash part */
|
| + if (!ttisnil(gval(gnode(t, i)))) { /* a non-nil value? */
|
| + setobj2s(L, key, gkey(gnode(t, i)));
|
| + setobj2s(L, key+1, gval(gnode(t, i)));
|
| + return 1;
|
| + }
|
| + }
|
| + return 0; /* no more elements */
|
| +}
|
| +
|
| +
|
| +/*
|
| +** {=============================================================
|
| +** Rehash
|
| +** ==============================================================
|
| +*/
|
| +
|
| +
|
| +static int computesizes (int nums[], int *narray) {
|
| + int i;
|
| + int twotoi; /* 2^i */
|
| + int a = 0; /* number of elements smaller than 2^i */
|
| + int na = 0; /* number of elements to go to array part */
|
| + int n = 0; /* optimal size for array part */
|
| + for (i = 0, twotoi = 1; twotoi/2 < *narray; i++, twotoi *= 2) {
|
| + if (nums[i] > 0) {
|
| + a += nums[i];
|
| + if (a > twotoi/2) { /* more than half elements present? */
|
| + n = twotoi; /* optimal size (till now) */
|
| + na = a; /* all elements smaller than n will go to array part */
|
| + }
|
| + }
|
| + if (a == *narray) break; /* all elements already counted */
|
| + }
|
| + *narray = n;
|
| + lua_assert(*narray/2 <= na && na <= *narray);
|
| + return na;
|
| +}
|
| +
|
| +
|
| +static int countint (const TValue *key, int *nums) {
|
| + int k = arrayindex(key);
|
| + if (0 < k && k <= MAXASIZE) { /* is `key' an appropriate array index? */
|
| + nums[luaO_ceillog2(k)]++; /* count as such */
|
| + return 1;
|
| + }
|
| + else
|
| + return 0;
|
| +}
|
| +
|
| +
|
| +static int numusearray (const Table *t, int *nums) {
|
| + int lg;
|
| + int ttlg; /* 2^lg */
|
| + int ause = 0; /* summation of `nums' */
|
| + int i = 1; /* count to traverse all array keys */
|
| + for (lg=0, ttlg=1; lg<=MAXBITS; lg++, ttlg*=2) { /* for each slice */
|
| + int lc = 0; /* counter */
|
| + int lim = ttlg;
|
| + if (lim > t->sizearray) {
|
| + lim = t->sizearray; /* adjust upper limit */
|
| + if (i > lim)
|
| + break; /* no more elements to count */
|
| + }
|
| + /* count elements in range (2^(lg-1), 2^lg] */
|
| + for (; i <= lim; i++) {
|
| + if (!ttisnil(&t->array[i-1]))
|
| + lc++;
|
| + }
|
| + nums[lg] += lc;
|
| + ause += lc;
|
| + }
|
| + return ause;
|
| +}
|
| +
|
| +
|
| +static int numusehash (const Table *t, int *nums, int *pnasize) {
|
| + int totaluse = 0; /* total number of elements */
|
| + int ause = 0; /* summation of `nums' */
|
| + int i = sizenode(t);
|
| + while (i--) {
|
| + Node *n = &t->node[i];
|
| + if (!ttisnil(gval(n))) {
|
| + ause += countint(gkey(n), nums);
|
| + totaluse++;
|
| + }
|
| + }
|
| + *pnasize += ause;
|
| + return totaluse;
|
| +}
|
| +
|
| +
|
| +static void setarrayvector (lua_State *L, Table *t, int size) {
|
| + int i;
|
| + luaM_reallocvector(L, t->array, t->sizearray, size, TValue);
|
| + for (i=t->sizearray; i<size; i++)
|
| + setnilvalue(&t->array[i]);
|
| + t->sizearray = size;
|
| +}
|
| +
|
| +
|
| +static void setnodevector (lua_State *L, Table *t, int size) {
|
| + int lsize;
|
| + if (size == 0) { /* no elements to hash part? */
|
| + t->node = cast(Node *, dummynode); /* use common `dummynode' */
|
| + lsize = 0;
|
| + }
|
| + else {
|
| + int i;
|
| + lsize = luaO_ceillog2(size);
|
| + if (lsize > MAXBITS)
|
| + luaG_runerror(L, "table overflow");
|
| + size = twoto(lsize);
|
| + t->node = luaM_newvector(L, size, Node);
|
| + for (i=0; i<size; i++) {
|
| + Node *n = gnode(t, i);
|
| + gnext(n) = NULL;
|
| + setnilvalue(gkey(n));
|
| + setnilvalue(gval(n));
|
| + }
|
| + }
|
| + t->lsizenode = cast_byte(lsize);
|
| + t->lastfree = gnode(t, size); /* all positions are free */
|
| +}
|
| +
|
| +
|
| +void luaH_resize (lua_State *L, Table *t, int nasize, int nhsize) {
|
| + int i;
|
| + int oldasize = t->sizearray;
|
| + int oldhsize = t->lsizenode;
|
| + Node *nold = t->node; /* save old hash ... */
|
| + if (nasize > oldasize) /* array part must grow? */
|
| + setarrayvector(L, t, nasize);
|
| + /* create new hash part with appropriate size */
|
| + setnodevector(L, t, nhsize);
|
| + if (nasize < oldasize) { /* array part must shrink? */
|
| + t->sizearray = nasize;
|
| + /* re-insert elements from vanishing slice */
|
| + for (i=nasize; i<oldasize; i++) {
|
| + if (!ttisnil(&t->array[i]))
|
| + luaH_setint(L, t, i + 1, &t->array[i]);
|
| + }
|
| + /* shrink array */
|
| + luaM_reallocvector(L, t->array, oldasize, nasize, TValue);
|
| + }
|
| + /* re-insert elements from hash part */
|
| + for (i = twoto(oldhsize) - 1; i >= 0; i--) {
|
| + Node *old = nold+i;
|
| + if (!ttisnil(gval(old))) {
|
| + /* doesn't need barrier/invalidate cache, as entry was
|
| + already present in the table */
|
| + setobjt2t(L, luaH_set(L, t, gkey(old)), gval(old));
|
| + }
|
| + }
|
| + if (!isdummy(nold))
|
| + luaM_freearray(L, nold, cast(size_t, twoto(oldhsize))); /* free old array */
|
| +}
|
| +
|
| +
|
| +void luaH_resizearray (lua_State *L, Table *t, int nasize) {
|
| + int nsize = isdummy(t->node) ? 0 : sizenode(t);
|
| + luaH_resize(L, t, nasize, nsize);
|
| +}
|
| +
|
| +
|
| +static void rehash (lua_State *L, Table *t, const TValue *ek) {
|
| + int nasize, na;
|
| + int nums[MAXBITS+1]; /* nums[i] = number of keys with 2^(i-1) < k <= 2^i */
|
| + int i;
|
| + int totaluse;
|
| + for (i=0; i<=MAXBITS; i++) nums[i] = 0; /* reset counts */
|
| + nasize = numusearray(t, nums); /* count keys in array part */
|
| + totaluse = nasize; /* all those keys are integer keys */
|
| + totaluse += numusehash(t, nums, &nasize); /* count keys in hash part */
|
| + /* count extra key */
|
| + nasize += countint(ek, nums);
|
| + totaluse++;
|
| + /* compute new size for array part */
|
| + na = computesizes(nums, &nasize);
|
| + /* resize the table to new computed sizes */
|
| + luaH_resize(L, t, nasize, totaluse - na);
|
| +}
|
| +
|
| +
|
| +
|
| +/*
|
| +** }=============================================================
|
| +*/
|
| +
|
| +
|
| +Table *luaH_new (lua_State *L) {
|
| + Table *t = &luaC_newobj(L, LUA_TTABLE, sizeof(Table), NULL, 0)->h;
|
| + t->metatable = NULL;
|
| + t->flags = cast_byte(~0);
|
| + t->array = NULL;
|
| + t->sizearray = 0;
|
| + setnodevector(L, t, 0);
|
| + return t;
|
| +}
|
| +
|
| +
|
| +void luaH_free (lua_State *L, Table *t) {
|
| + if (!isdummy(t->node))
|
| + luaM_freearray(L, t->node, cast(size_t, sizenode(t)));
|
| + luaM_freearray(L, t->array, t->sizearray);
|
| + luaM_free(L, t);
|
| +}
|
| +
|
| +
|
| +static Node *getfreepos (Table *t) {
|
| + while (t->lastfree > t->node) {
|
| + t->lastfree--;
|
| + if (ttisnil(gkey(t->lastfree)))
|
| + return t->lastfree;
|
| + }
|
| + return NULL; /* could not find a free place */
|
| +}
|
| +
|
| +
|
| +
|
| +/*
|
| +** inserts a new key into a hash table; first, check whether key's main
|
| +** position is free. If not, check whether colliding node is in its main
|
| +** position or not: if it is not, move colliding node to an empty place and
|
| +** put new key in its main position; otherwise (colliding node is in its main
|
| +** position), new key goes to an empty position.
|
| +*/
|
| +TValue *luaH_newkey (lua_State *L, Table *t, const TValue *key) {
|
| + Node *mp;
|
| + if (ttisnil(key)) luaG_runerror(L, "table index is nil");
|
| + else if (ttisnumber(key) && luai_numisnan(L, nvalue(key)))
|
| + luaG_runerror(L, "table index is NaN");
|
| + mp = mainposition(t, key);
|
| + if (!ttisnil(gval(mp)) || isdummy(mp)) { /* main position is taken? */
|
| + Node *othern;
|
| + Node *n = getfreepos(t); /* get a free place */
|
| + if (n == NULL) { /* cannot find a free place? */
|
| + rehash(L, t, key); /* grow table */
|
| + /* whatever called 'newkey' take care of TM cache and GC barrier */
|
| + return luaH_set(L, t, key); /* insert key into grown table */
|
| + }
|
| + lua_assert(!isdummy(n));
|
| + othern = mainposition(t, gkey(mp));
|
| + if (othern != mp) { /* is colliding node out of its main position? */
|
| + /* yes; move colliding node into free position */
|
| + while (gnext(othern) != mp) othern = gnext(othern); /* find previous */
|
| + gnext(othern) = n; /* redo the chain with `n' in place of `mp' */
|
| + *n = *mp; /* copy colliding node into free pos. (mp->next also goes) */
|
| + gnext(mp) = NULL; /* now `mp' is free */
|
| + setnilvalue(gval(mp));
|
| + }
|
| + else { /* colliding node is in its own main position */
|
| + /* new node will go into free position */
|
| + gnext(n) = gnext(mp); /* chain new position */
|
| + gnext(mp) = n;
|
| + mp = n;
|
| + }
|
| + }
|
| + setobj2t(L, gkey(mp), key);
|
| + luaC_barrierback(L, obj2gco(t), key);
|
| + lua_assert(ttisnil(gval(mp)));
|
| + return gval(mp);
|
| +}
|
| +
|
| +
|
| +/*
|
| +** search function for integers
|
| +*/
|
| +const TValue *luaH_getint (Table *t, int key) {
|
| + /* (1 <= key && key <= t->sizearray) */
|
| + if (cast(unsigned int, key-1) < cast(unsigned int, t->sizearray))
|
| + return &t->array[key-1];
|
| + else {
|
| + lua_Number nk = cast_num(key);
|
| + Node *n = hashnum(t, nk);
|
| + do { /* check whether `key' is somewhere in the chain */
|
| + if (ttisnumber(gkey(n)) && luai_numeq(nvalue(gkey(n)), nk))
|
| + return gval(n); /* that's it */
|
| + else n = gnext(n);
|
| + } while (n);
|
| + return luaO_nilobject;
|
| + }
|
| +}
|
| +
|
| +
|
| +/*
|
| +** search function for short strings
|
| +*/
|
| +const TValue *luaH_getstr (Table *t, TString *key) {
|
| + Node *n = hashstr(t, key);
|
| + lua_assert(key->tsv.tt == LUA_TSHRSTR);
|
| + do { /* check whether `key' is somewhere in the chain */
|
| + if (ttisshrstring(gkey(n)) && eqshrstr(rawtsvalue(gkey(n)), key))
|
| + return gval(n); /* that's it */
|
| + else n = gnext(n);
|
| + } while (n);
|
| + return luaO_nilobject;
|
| +}
|
| +
|
| +
|
| +/*
|
| +** main search function
|
| +*/
|
| +const TValue *luaH_get (Table *t, const TValue *key) {
|
| + switch (ttype(key)) {
|
| + case LUA_TSHRSTR: return luaH_getstr(t, rawtsvalue(key));
|
| + case LUA_TNIL: return luaO_nilobject;
|
| + case LUA_TNUMBER: {
|
| + int k;
|
| + lua_Number n = nvalue(key);
|
| + lua_number2int(k, n);
|
| + if (luai_numeq(cast_num(k), n)) /* index is int? */
|
| + return luaH_getint(t, k); /* use specialized version */
|
| + /* else go through */
|
| + }
|
| + default: {
|
| + Node *n = mainposition(t, key);
|
| + do { /* check whether `key' is somewhere in the chain */
|
| + if (luaV_rawequalobj(gkey(n), key))
|
| + return gval(n); /* that's it */
|
| + else n = gnext(n);
|
| + } while (n);
|
| + return luaO_nilobject;
|
| + }
|
| + }
|
| +}
|
| +
|
| +
|
| +/*
|
| +** beware: when using this function you probably need to check a GC
|
| +** barrier and invalidate the TM cache.
|
| +*/
|
| +TValue *luaH_set (lua_State *L, Table *t, const TValue *key) {
|
| + const TValue *p = luaH_get(t, key);
|
| + if (p != luaO_nilobject)
|
| + return cast(TValue *, p);
|
| + else return luaH_newkey(L, t, key);
|
| +}
|
| +
|
| +
|
| +void luaH_setint (lua_State *L, Table *t, int key, TValue *value) {
|
| + const TValue *p = luaH_getint(t, key);
|
| + TValue *cell;
|
| + if (p != luaO_nilobject)
|
| + cell = cast(TValue *, p);
|
| + else {
|
| + TValue k;
|
| + setnvalue(&k, cast_num(key));
|
| + cell = luaH_newkey(L, t, &k);
|
| + }
|
| + setobj2t(L, cell, value);
|
| +}
|
| +
|
| +
|
| +static int unbound_search (Table *t, unsigned int j) {
|
| + unsigned int i = j; /* i is zero or a present index */
|
| + j++;
|
| + /* find `i' and `j' such that i is present and j is not */
|
| + while (!ttisnil(luaH_getint(t, j))) {
|
| + i = j;
|
| + j *= 2;
|
| + if (j > cast(unsigned int, MAX_INT)) { /* overflow? */
|
| + /* table was built with bad purposes: resort to linear search */
|
| + i = 1;
|
| + while (!ttisnil(luaH_getint(t, i))) i++;
|
| + return i - 1;
|
| + }
|
| + }
|
| + /* now do a binary search between them */
|
| + while (j - i > 1) {
|
| + unsigned int m = (i+j)/2;
|
| + if (ttisnil(luaH_getint(t, m))) j = m;
|
| + else i = m;
|
| + }
|
| + return i;
|
| +}
|
| +
|
| +
|
| +/*
|
| +** Try to find a boundary in table `t'. A `boundary' is an integer index
|
| +** such that t[i] is non-nil and t[i+1] is nil (and 0 if t[1] is nil).
|
| +*/
|
| +int luaH_getn (Table *t) {
|
| + unsigned int j = t->sizearray;
|
| + if (j > 0 && ttisnil(&t->array[j - 1])) {
|
| + /* there is a boundary in the array part: (binary) search for it */
|
| + unsigned int i = 0;
|
| + while (j - i > 1) {
|
| + unsigned int m = (i+j)/2;
|
| + if (ttisnil(&t->array[m - 1])) j = m;
|
| + else i = m;
|
| + }
|
| + return i;
|
| + }
|
| + /* else must find a boundary in hash part */
|
| + else if (isdummy(t->node)) /* hash part is empty? */
|
| + return j; /* that is easy... */
|
| + else return unbound_search(t, j);
|
| +}
|
| +
|
| +
|
| +
|
| +#if defined(LUA_DEBUG)
|
| +
|
| +Node *luaH_mainposition (const Table *t, const TValue *key) {
|
| + return mainposition(t, key);
|
| +}
|
| +
|
| +int luaH_isdummy (Node *n) { return isdummy(n); }
|
| +
|
| +#endif
|
|
|
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