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-rw-r--r--3rdparty/lua/src/ltable.c769
1 files changed, 540 insertions, 229 deletions
diff --git a/3rdparty/lua/src/ltable.c b/3rdparty/lua/src/ltable.c
index d080189f28d..1b1cd2415b6 100644
--- a/3rdparty/lua/src/ltable.c
+++ b/3rdparty/lua/src/ltable.c
@@ -1,5 +1,5 @@
/*
-** $Id: ltable.c,v 2.118 2016/11/07 12:38:35 roberto Exp $
+** $Id: ltable.c $
** Lua tables (hash)
** See Copyright Notice in lua.h
*/
@@ -40,46 +40,80 @@
/*
-** Maximum size of array part (MAXASIZE) is 2^MAXABITS. MAXABITS is
-** the largest integer such that MAXASIZE fits in an unsigned int.
+** MAXABITS is the largest integer such that MAXASIZE fits in an
+** unsigned int.
*/
#define MAXABITS cast_int(sizeof(int) * CHAR_BIT - 1)
-#define MAXASIZE (1u << MAXABITS)
+
/*
-** Maximum size of hash part is 2^MAXHBITS. MAXHBITS is the largest
-** integer such that 2^MAXHBITS fits in a signed int. (Note that the
-** maximum number of elements in a table, 2^MAXABITS + 2^MAXHBITS, still
-** fits comfortably in an unsigned int.)
+** MAXASIZE is the maximum size of the array part. It is the minimum
+** between 2^MAXABITS and the maximum size that, measured in bytes,
+** fits in a 'size_t'.
+*/
+#define MAXASIZE luaM_limitN(1u << MAXABITS, TValue)
+
+/*
+** MAXHBITS is the largest integer such that 2^MAXHBITS fits in a
+** signed int.
*/
#define MAXHBITS (MAXABITS - 1)
-#define hashpow2(t,n) (gnode(t, lmod((n), sizenode(t))))
+/*
+** MAXHSIZE is the maximum size of the hash part. It is the minimum
+** between 2^MAXHBITS and the maximum size such that, measured in bytes,
+** it fits in a 'size_t'.
+*/
+#define MAXHSIZE luaM_limitN(1u << MAXHBITS, Node)
-#define hashstr(t,str) hashpow2(t, (str)->hash)
-#define hashboolean(t,p) hashpow2(t, p)
-#define hashint(t,i) hashpow2(t, i)
+/*
+** When the original hash value is good, hashing by a power of 2
+** avoids the cost of '%'.
+*/
+#define hashpow2(t,n) (gnode(t, lmod((n), sizenode(t))))
/*
-** for some types, it is better to avoid modulus by power of 2, as
-** they tend to have many 2 factors.
+** for other types, it is better to avoid modulo by power of 2, as
+** they can have many 2 factors.
*/
#define hashmod(t,n) (gnode(t, ((n) % ((sizenode(t)-1)|1))))
+#define hashstr(t,str) hashpow2(t, (str)->hash)
+#define hashboolean(t,p) hashpow2(t, p)
+
+
#define hashpointer(t,p) hashmod(t, point2uint(p))
#define dummynode (&dummynode_)
static const Node dummynode_ = {
- {NILCONSTANT}, /* value */
- {{NILCONSTANT, 0}} /* key */
+ {{NULL}, LUA_VEMPTY, /* value's value and type */
+ LUA_VNIL, 0, {NULL}} /* key type, next, and key value */
};
+static const TValue absentkey = {ABSTKEYCONSTANT};
+
+
+/*
+** Hash for integers. To allow a good hash, use the remainder operator
+** ('%'). If integer fits as a non-negative int, compute an int
+** remainder, which is faster. Otherwise, use an unsigned-integer
+** remainder, which uses all bits and ensures a non-negative result.
+*/
+static Node *hashint (const Table *t, lua_Integer i) {
+ lua_Unsigned ui = l_castS2U(i);
+ if (ui <= (unsigned int)INT_MAX)
+ return hashmod(t, cast_int(ui));
+ else
+ return hashmod(t, ui);
+}
+
+
/*
** Hash for floating-point numbers.
** The main computation should be just
@@ -103,51 +137,187 @@ static int l_hashfloat (lua_Number n) {
return 0;
}
else { /* normal case */
- unsigned int u = cast(unsigned int, i) + cast(unsigned int, ni);
- return cast_int(u <= cast(unsigned int, INT_MAX) ? u : ~u);
+ unsigned int u = cast_uint(i) + cast_uint(ni);
+ return cast_int(u <= cast_uint(INT_MAX) ? u : ~u);
}
}
#endif
/*
-** 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_TNUMINT:
- return hashint(t, ivalue(key));
- case LUA_TNUMFLT:
- return hashmod(t, l_hashfloat(fltvalue(key)));
- case LUA_TSHRSTR:
- return hashstr(t, tsvalue(key));
- case LUA_TLNGSTR:
- return hashpow2(t, luaS_hashlongstr(tsvalue(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));
+** returns the 'main' position of an element in a table (that is,
+** the index of its hash value).
+*/
+static Node *mainpositionTV (const Table *t, const TValue *key) {
+ switch (ttypetag(key)) {
+ case LUA_VNUMINT: {
+ lua_Integer i = ivalue(key);
+ return hashint(t, i);
+ }
+ case LUA_VNUMFLT: {
+ lua_Number n = fltvalue(key);
+ return hashmod(t, l_hashfloat(n));
+ }
+ case LUA_VSHRSTR: {
+ TString *ts = tsvalue(key);
+ return hashstr(t, ts);
+ }
+ case LUA_VLNGSTR: {
+ TString *ts = tsvalue(key);
+ return hashpow2(t, luaS_hashlongstr(ts));
+ }
+ case LUA_VFALSE:
+ return hashboolean(t, 0);
+ case LUA_VTRUE:
+ return hashboolean(t, 1);
+ case LUA_VLIGHTUSERDATA: {
+ void *p = pvalue(key);
+ return hashpointer(t, p);
+ }
+ case LUA_VLCF: {
+ lua_CFunction f = fvalue(key);
+ return hashpointer(t, f);
+ }
+ default: {
+ GCObject *o = gcvalue(key);
+ return hashpointer(t, o);
+ }
+ }
+}
+
+
+l_sinline Node *mainpositionfromnode (const Table *t, Node *nd) {
+ TValue key;
+ getnodekey(cast(lua_State *, NULL), &key, nd);
+ return mainpositionTV(t, &key);
+}
+
+
+/*
+** Check whether key 'k1' is equal to the key in node 'n2'. This
+** equality is raw, so there are no metamethods. Floats with integer
+** values have been normalized, so integers cannot be equal to
+** floats. It is assumed that 'eqshrstr' is simply pointer equality, so
+** that short strings are handled in the default case.
+** A true 'deadok' means to accept dead keys as equal to their original
+** values. All dead keys are compared in the default case, by pointer
+** identity. (Only collectable objects can produce dead keys.) Note that
+** dead long strings are also compared by identity.
+** Once a key is dead, its corresponding value may be collected, and
+** then another value can be created with the same address. If this
+** other value is given to 'next', 'equalkey' will signal a false
+** positive. In a regular traversal, this situation should never happen,
+** as all keys given to 'next' came from the table itself, and therefore
+** could not have been collected. Outside a regular traversal, we
+** have garbage in, garbage out. What is relevant is that this false
+** positive does not break anything. (In particular, 'next' will return
+** some other valid item on the table or nil.)
+*/
+static int equalkey (const TValue *k1, const Node *n2, int deadok) {
+ if ((rawtt(k1) != keytt(n2)) && /* not the same variants? */
+ !(deadok && keyisdead(n2) && iscollectable(k1)))
+ return 0; /* cannot be same key */
+ switch (keytt(n2)) {
+ case LUA_VNIL: case LUA_VFALSE: case LUA_VTRUE:
+ return 1;
+ case LUA_VNUMINT:
+ return (ivalue(k1) == keyival(n2));
+ case LUA_VNUMFLT:
+ return luai_numeq(fltvalue(k1), fltvalueraw(keyval(n2)));
+ case LUA_VLIGHTUSERDATA:
+ return pvalue(k1) == pvalueraw(keyval(n2));
+ case LUA_VLCF:
+ return fvalue(k1) == fvalueraw(keyval(n2));
+ case ctb(LUA_VLNGSTR):
+ return luaS_eqlngstr(tsvalue(k1), keystrval(n2));
default:
- lua_assert(!ttisdeadkey(key));
- return hashpointer(t, gcvalue(key));
+ return gcvalue(k1) == gcvalueraw(keyval(n2));
+ }
+}
+
+
+/*
+** True if value of 'alimit' is equal to the real size of the array
+** part of table 't'. (Otherwise, the array part must be larger than
+** 'alimit'.)
+*/
+#define limitequalsasize(t) (isrealasize(t) || ispow2((t)->alimit))
+
+
+/*
+** Returns the real size of the 'array' array
+*/
+LUAI_FUNC unsigned int luaH_realasize (const Table *t) {
+ if (limitequalsasize(t))
+ return t->alimit; /* this is the size */
+ else {
+ unsigned int size = t->alimit;
+ /* compute the smallest power of 2 not smaller than 'n' */
+ size |= (size >> 1);
+ size |= (size >> 2);
+ size |= (size >> 4);
+ size |= (size >> 8);
+ size |= (size >> 16);
+#if (UINT_MAX >> 30) > 3
+ size |= (size >> 32); /* unsigned int has more than 32 bits */
+#endif
+ size++;
+ lua_assert(ispow2(size) && size/2 < t->alimit && t->alimit < size);
+ return size;
}
}
/*
-** returns the index for 'key' if 'key' is an appropriate key to live in
-** the array part of the table, 0 otherwise.
+** Check whether real size of the array is a power of 2.
+** (If it is not, 'alimit' cannot be changed to any other value
+** without changing the real size.)
+*/
+static int ispow2realasize (const Table *t) {
+ return (!isrealasize(t) || ispow2(t->alimit));
+}
+
+
+static unsigned int setlimittosize (Table *t) {
+ t->alimit = luaH_realasize(t);
+ setrealasize(t);
+ return t->alimit;
+}
+
+
+#define limitasasize(t) check_exp(isrealasize(t), t->alimit)
+
+
+
+/*
+** "Generic" get version. (Not that generic: not valid for integers,
+** which may be in array part, nor for floats with integral values.)
+** See explanation about 'deadok' in function 'equalkey'.
*/
-static unsigned int arrayindex (const TValue *key) {
- if (ttisinteger(key)) {
- lua_Integer k = ivalue(key);
- if (0 < k && (lua_Unsigned)k <= MAXASIZE)
- return cast(unsigned int, k); /* 'key' is an appropriate array index */
+static const TValue *getgeneric (Table *t, const TValue *key, int deadok) {
+ Node *n = mainpositionTV(t, key);
+ for (;;) { /* check whether 'key' is somewhere in the chain */
+ if (equalkey(key, n, deadok))
+ return gval(n); /* that's it */
+ else {
+ int nx = gnext(n);
+ if (nx == 0)
+ return &absentkey; /* not found */
+ n += nx;
+ }
}
- return 0; /* 'key' did not match some condition */
+}
+
+
+/*
+** returns the index for 'k' if 'k' is an appropriate key to live in
+** the array part of a table, 0 otherwise.
+*/
+static unsigned int arrayindex (lua_Integer k) {
+ if (l_castS2U(k) - 1u < MAXASIZE) /* 'k' in [1, MAXASIZE]? */
+ return cast_uint(k); /* 'key' is an appropriate array index */
+ else
+ return 0;
}
@@ -156,46 +326,39 @@ static unsigned int arrayindex (const TValue *key) {
** elements in the array part, then elements in the hash part. The
** beginning of a traversal is signaled by 0.
*/
-static unsigned int findindex (lua_State *L, Table *t, StkId key) {
+static unsigned int findindex (lua_State *L, Table *t, TValue *key,
+ unsigned int asize) {
unsigned int i;
if (ttisnil(key)) return 0; /* first iteration */
- i = arrayindex(key);
- if (i != 0 && i <= t->sizearray) /* is 'key' inside array part? */
+ i = ttisinteger(key) ? arrayindex(ivalue(key)) : 0;
+ if (i - 1u < asize) /* is 'key' inside array part? */
return i; /* yes; that's the index */
else {
- int nx;
- 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 + 1) + t->sizearray;
- }
- nx = gnext(n);
- if (nx == 0)
- luaG_runerror(L, "invalid key to 'next'"); /* key not found */
- else n += nx;
- }
+ const TValue *n = getgeneric(t, key, 1);
+ if (l_unlikely(isabstkey(n)))
+ luaG_runerror(L, "invalid key to 'next'"); /* key not found */
+ i = cast_int(nodefromval(n) - gnode(t, 0)); /* key index in hash table */
+ /* hash elements are numbered after array ones */
+ return (i + 1) + asize;
}
}
int luaH_next (lua_State *L, Table *t, StkId key) {
- unsigned int i = findindex(L, t, key); /* find original element */
- for (; i < t->sizearray; i++) { /* try first array part */
- if (!ttisnil(&t->array[i])) { /* a non-nil value? */
- setivalue(key, i + 1);
- setobj2s(L, key+1, &t->array[i]);
+ unsigned int asize = luaH_realasize(t);
+ unsigned int i = findindex(L, t, s2v(key), asize); /* find original key */
+ for (; i < asize; i++) { /* try first array part */
+ if (!isempty(&t->array[i])) { /* a non-empty entry? */
+ setivalue(s2v(key), i + 1);
+ setobj2s(L, key + 1, &t->array[i]);
return 1;
}
}
- for (i -= t->sizearray; cast_int(i) < sizenode(t); i++) { /* 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)));
+ for (i -= asize; cast_int(i) < sizenode(t); i++) { /* hash part */
+ if (!isempty(gval(gnode(t, i)))) { /* a non-empty entry? */
+ Node *n = gnode(t, i);
+ getnodekey(L, s2v(key), n);
+ setobj2s(L, key + 1, gval(n));
return 1;
}
}
@@ -203,6 +366,12 @@ int luaH_next (lua_State *L, Table *t, StkId key) {
}
+static void freehash (lua_State *L, Table *t) {
+ if (!isdummy(t))
+ luaM_freearray(L, t->node, cast_sizet(sizenode(t)));
+}
+
+
/*
** {=============================================================
** Rehash
@@ -214,7 +383,8 @@ int luaH_next (lua_State *L, Table *t, StkId key) {
** "count array" where 'nums[i]' is the number of integers in the table
** between 2^(i - 1) + 1 and 2^i. 'pna' enters with the total number of
** integer keys in the table and leaves with the number of keys that
-** will go to the array part; return the optimal size.
+** will go to the array part; return the optimal size. (The condition
+** 'twotoi > 0' in the for loop stops the loop if 'twotoi' overflows.)
*/
static unsigned int computesizes (unsigned int nums[], unsigned int *pna) {
int i;
@@ -223,13 +393,13 @@ static unsigned int computesizes (unsigned int nums[], unsigned int *pna) {
unsigned int na = 0; /* number of elements to go to array part */
unsigned int optimal = 0; /* optimal size for array part */
/* loop while keys can fill more than half of total size */
- for (i = 0, twotoi = 1; *pna > twotoi / 2; i++, twotoi *= 2) {
- if (nums[i] > 0) {
- a += nums[i];
- if (a > twotoi/2) { /* more than half elements present? */
- optimal = twotoi; /* optimal size (till now) */
- na = a; /* all elements up to 'optimal' will go to array part */
- }
+ for (i = 0, twotoi = 1;
+ twotoi > 0 && *pna > twotoi / 2;
+ i++, twotoi *= 2) {
+ a += nums[i];
+ if (a > twotoi/2) { /* more than half elements present? */
+ optimal = twotoi; /* optimal size (till now) */
+ na = a; /* all elements up to 'optimal' will go to array part */
}
}
lua_assert((optimal == 0 || optimal / 2 < na) && na <= optimal);
@@ -238,7 +408,7 @@ static unsigned int computesizes (unsigned int nums[], unsigned int *pna) {
}
-static int countint (const TValue *key, unsigned int *nums) {
+static int countint (lua_Integer key, unsigned int *nums) {
unsigned int k = arrayindex(key);
if (k != 0) { /* is 'key' an appropriate array index? */
nums[luaO_ceillog2(k)]++; /* count as such */
@@ -259,18 +429,19 @@ static unsigned int numusearray (const Table *t, unsigned int *nums) {
unsigned int ttlg; /* 2^lg */
unsigned int ause = 0; /* summation of 'nums' */
unsigned int i = 1; /* count to traverse all array keys */
+ unsigned int asize = limitasasize(t); /* real array size */
/* traverse each slice */
for (lg = 0, ttlg = 1; lg <= MAXABITS; lg++, ttlg *= 2) {
unsigned int lc = 0; /* counter */
unsigned int lim = ttlg;
- if (lim > t->sizearray) {
- lim = t->sizearray; /* adjust upper limit */
+ if (lim > asize) {
+ lim = asize; /* 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]))
+ if (!isempty(&t->array[i-1]))
lc++;
}
nums[lg] += lc;
@@ -286,8 +457,9 @@ static int numusehash (const Table *t, unsigned int *nums, unsigned int *pna) {
int i = sizenode(t);
while (i--) {
Node *n = &t->node[i];
- if (!ttisnil(gval(n))) {
- ause += countint(gkey(n), nums);
+ if (!isempty(gval(n))) {
+ if (keyisinteger(n))
+ ause += countint(keyival(n), nums);
totaluse++;
}
}
@@ -296,15 +468,13 @@ static int numusehash (const Table *t, unsigned int *nums, unsigned int *pna) {
}
-static void setarrayvector (lua_State *L, Table *t, unsigned int size) {
- unsigned 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;
-}
-
-
+/*
+** Creates an array for the hash part of a table with the given
+** size, or reuses the dummy node if size is zero.
+** The computation for size overflow is in two steps: the first
+** comparison ensures that the shift in the second one does not
+** overflow.
+*/
static void setnodevector (lua_State *L, Table *t, unsigned int size) {
if (size == 0) { /* no elements to hash part? */
t->node = cast(Node *, dummynode); /* use common 'dummynode' */
@@ -314,15 +484,15 @@ static void setnodevector (lua_State *L, Table *t, unsigned int size) {
else {
int i;
int lsize = luaO_ceillog2(size);
- if (lsize > MAXHBITS)
+ if (lsize > MAXHBITS || (1u << lsize) > MAXHSIZE)
luaG_runerror(L, "table overflow");
size = twoto(lsize);
t->node = luaM_newvector(L, size, Node);
for (i = 0; i < (int)size; i++) {
Node *n = gnode(t, i);
gnext(n) = 0;
- setnilvalue(wgkey(n));
- setnilvalue(gval(n));
+ setnilkey(n);
+ setempty(gval(n));
}
t->lsizenode = cast_byte(lsize);
t->lastfree = gnode(t, size); /* all positions are free */
@@ -330,38 +500,88 @@ static void setnodevector (lua_State *L, Table *t, unsigned int size) {
}
-void luaH_resize (lua_State *L, Table *t, unsigned int nasize,
+/*
+** (Re)insert all elements from the hash part of 'ot' into table 't'.
+*/
+static void reinsert (lua_State *L, Table *ot, Table *t) {
+ int j;
+ int size = sizenode(ot);
+ for (j = 0; j < size; j++) {
+ Node *old = gnode(ot, j);
+ if (!isempty(gval(old))) {
+ /* doesn't need barrier/invalidate cache, as entry was
+ already present in the table */
+ TValue k;
+ getnodekey(L, &k, old);
+ luaH_set(L, t, &k, gval(old));
+ }
+ }
+}
+
+
+/*
+** Exchange the hash part of 't1' and 't2'.
+*/
+static void exchangehashpart (Table *t1, Table *t2) {
+ lu_byte lsizenode = t1->lsizenode;
+ Node *node = t1->node;
+ Node *lastfree = t1->lastfree;
+ t1->lsizenode = t2->lsizenode;
+ t1->node = t2->node;
+ t1->lastfree = t2->lastfree;
+ t2->lsizenode = lsizenode;
+ t2->node = node;
+ t2->lastfree = lastfree;
+}
+
+
+/*
+** Resize table 't' for the new given sizes. Both allocations (for
+** the hash part and for the array part) can fail, which creates some
+** subtleties. If the first allocation, for the hash part, fails, an
+** error is raised and that is it. Otherwise, it copies the elements from
+** the shrinking part of the array (if it is shrinking) into the new
+** hash. Then it reallocates the array part. If that fails, the table
+** is in its original state; the function frees the new hash part and then
+** raises the allocation error. Otherwise, it sets the new hash part
+** into the table, initializes the new part of the array (if any) with
+** nils and reinserts the elements of the old hash back into the new
+** parts of the table.
+*/
+void luaH_resize (lua_State *L, Table *t, unsigned int newasize,
unsigned int nhsize) {
unsigned int i;
- int j;
- unsigned int oldasize = t->sizearray;
- int oldhsize = allocsizenode(t);
- 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]))
+ Table newt; /* to keep the new hash part */
+ unsigned int oldasize = setlimittosize(t);
+ TValue *newarray;
+ /* create new hash part with appropriate size into 'newt' */
+ setnodevector(L, &newt, nhsize);
+ if (newasize < oldasize) { /* will array shrink? */
+ t->alimit = newasize; /* pretend array has new size... */
+ exchangehashpart(t, &newt); /* and new hash */
+ /* re-insert into the new hash the elements from vanishing slice */
+ for (i = newasize; i < oldasize; i++) {
+ if (!isempty(&t->array[i]))
luaH_setint(L, t, i + 1, &t->array[i]);
}
- /* shrink array */
- luaM_reallocvector(L, t->array, oldasize, nasize, TValue);
+ t->alimit = oldasize; /* restore current size... */
+ exchangehashpart(t, &newt); /* and hash (in case of errors) */
}
- /* re-insert elements from hash part */
- for (j = oldhsize - 1; j >= 0; j--) {
- Node *old = nold + j;
- 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));
- }
+ /* allocate new array */
+ newarray = luaM_reallocvector(L, t->array, oldasize, newasize, TValue);
+ if (l_unlikely(newarray == NULL && newasize > 0)) { /* allocation failed? */
+ freehash(L, &newt); /* release new hash part */
+ luaM_error(L); /* raise error (with array unchanged) */
}
- if (oldhsize > 0) /* not the dummy node? */
- luaM_freearray(L, nold, cast(size_t, oldhsize)); /* free old hash */
+ /* allocation ok; initialize new part of the array */
+ exchangehashpart(t, &newt); /* 't' has the new hash ('newt' has the old) */
+ t->array = newarray; /* set new array part */
+ t->alimit = newasize;
+ for (i = oldasize; i < newasize; i++) /* clear new slice of the array */
+ setempty(&t->array[i]);
+ /* re-insert elements from old hash part into new parts */
+ reinsert(L, &newt, t); /* 'newt' now has the old hash */
+ freehash(L, &newt); /* free old hash part */
}
@@ -380,11 +600,13 @@ static void rehash (lua_State *L, Table *t, const TValue *ek) {
int i;
int totaluse;
for (i = 0; i <= MAXABITS; i++) nums[i] = 0; /* reset counts */
+ setlimittosize(t);
na = numusearray(t, nums); /* count keys in array part */
totaluse = na; /* all those keys are integer keys */
totaluse += numusehash(t, nums, &na); /* count keys in hash part */
/* count extra key */
- na += countint(ek, nums);
+ if (ttisinteger(ek))
+ na += countint(ivalue(ek), nums);
totaluse++;
/* compute new size for array part */
asize = computesizes(nums, &na);
@@ -400,21 +622,20 @@ static void rehash (lua_State *L, Table *t, const TValue *ek) {
Table *luaH_new (lua_State *L) {
- GCObject *o = luaC_newobj(L, LUA_TTABLE, sizeof(Table));
+ GCObject *o = luaC_newobj(L, LUA_VTABLE, sizeof(Table));
Table *t = gco2t(o);
t->metatable = NULL;
- t->flags = cast_byte(~0);
+ t->flags = cast_byte(maskflags); /* table has no metamethod fields */
t->array = NULL;
- t->sizearray = 0;
+ t->alimit = 0;
setnodevector(L, t, 0);
return t;
}
void luaH_free (lua_State *L, Table *t) {
- if (!isdummy(t))
- luaM_freearray(L, t->node, cast(size_t, sizenode(t)));
- luaM_freearray(L, t->array, t->sizearray);
+ freehash(L, t);
+ luaM_freearray(L, t->array, luaH_realasize(t));
luaM_free(L, t);
}
@@ -423,7 +644,7 @@ static Node *getfreepos (Table *t) {
if (!isdummy(t)) {
while (t->lastfree > t->node) {
t->lastfree--;
- if (ttisnil(gkey(t->lastfree)))
+ if (keyisnil(t->lastfree))
return t->lastfree;
}
}
@@ -439,30 +660,35 @@ static Node *getfreepos (Table *t) {
** 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) {
+void luaH_newkey (lua_State *L, Table *t, const TValue *key, TValue *value) {
Node *mp;
TValue aux;
- if (ttisnil(key)) luaG_runerror(L, "table index is nil");
+ if (l_unlikely(ttisnil(key)))
+ luaG_runerror(L, "table index is nil");
else if (ttisfloat(key)) {
+ lua_Number f = fltvalue(key);
lua_Integer k;
- if (luaV_tointeger(key, &k, 0)) { /* does index fit in an integer? */
+ if (luaV_flttointeger(f, &k, F2Ieq)) { /* does key fit in an integer? */
setivalue(&aux, k);
key = &aux; /* insert it as an integer */
}
- else if (luai_numisnan(fltvalue(key)))
+ else if (l_unlikely(luai_numisnan(f)))
luaG_runerror(L, "table index is NaN");
}
- mp = mainposition(t, key);
- if (!ttisnil(gval(mp)) || isdummy(t)) { /* main position is taken? */
+ if (ttisnil(value))
+ return; /* do not insert nil values */
+ mp = mainpositionTV(t, key);
+ if (!isempty(gval(mp)) || isdummy(t)) { /* main position is taken? */
Node *othern;
Node *f = getfreepos(t); /* get a free place */
if (f == NULL) { /* cannot find a free place? */
rehash(L, t, key); /* grow table */
/* whatever called 'newkey' takes care of TM cache */
- return luaH_set(L, t, key); /* insert key into grown table */
+ luaH_set(L, t, key, value); /* insert key into grown table */
+ return;
}
lua_assert(!isdummy(t));
- othern = mainposition(t, gkey(mp));
+ othern = mainpositionfromnode(t, mp);
if (othern != mp) { /* is colliding node out of its main position? */
/* yes; move colliding node into free position */
while (othern + gnext(othern) != mp) /* find previous */
@@ -473,7 +699,7 @@ TValue *luaH_newkey (lua_State *L, Table *t, const TValue *key) {
gnext(f) += cast_int(mp - f); /* correct 'next' */
gnext(mp) = 0; /* now 'mp' is free */
}
- setnilvalue(gval(mp));
+ setempty(gval(mp));
}
else { /* colliding node is in its own main position */
/* new node will go into free position */
@@ -484,24 +710,34 @@ TValue *luaH_newkey (lua_State *L, Table *t, const TValue *key) {
mp = f;
}
}
- setnodekey(L, &mp->i_key, key);
- luaC_barrierback(L, t, key);
- lua_assert(ttisnil(gval(mp)));
- return gval(mp);
+ setnodekey(L, mp, key);
+ luaC_barrierback(L, obj2gco(t), key);
+ lua_assert(isempty(gval(mp)));
+ setobj2t(L, gval(mp), value);
}
/*
-** search function for integers
+** Search function for integers. If integer is inside 'alimit', get it
+** directly from the array part. Otherwise, if 'alimit' is not equal to
+** the real size of the array, key still can be in the array part. In
+** this case, try to avoid a call to 'luaH_realasize' when key is just
+** one more than the limit (so that it can be incremented without
+** changing the real size of the array).
*/
const TValue *luaH_getint (Table *t, lua_Integer key) {
- /* (1 <= key && key <= t->sizearray) */
- if (l_castS2U(key) - 1 < t->sizearray)
+ if (l_castS2U(key) - 1u < t->alimit) /* 'key' in [1, t->alimit]? */
+ return &t->array[key - 1];
+ else if (!limitequalsasize(t) && /* key still may be in the array part? */
+ (l_castS2U(key) == t->alimit + 1 ||
+ l_castS2U(key) - 1u < luaH_realasize(t))) {
+ t->alimit = cast_uint(key); /* probably '#t' is here now */
return &t->array[key - 1];
+ }
else {
Node *n = hashint(t, key);
for (;;) { /* check whether 'key' is somewhere in the chain */
- if (ttisinteger(gkey(n)) && ivalue(gkey(n)) == key)
+ if (keyisinteger(n) && keyival(n) == key)
return gval(n); /* that's it */
else {
int nx = gnext(n);
@@ -509,7 +745,7 @@ const TValue *luaH_getint (Table *t, lua_Integer key) {
n += nx;
}
}
- return luaO_nilobject;
+ return &absentkey;
}
}
@@ -519,34 +755,14 @@ const TValue *luaH_getint (Table *t, lua_Integer key) {
*/
const TValue *luaH_getshortstr (Table *t, TString *key) {
Node *n = hashstr(t, key);
- lua_assert(key->tt == LUA_TSHRSTR);
- for (;;) { /* check whether 'key' is somewhere in the chain */
- const TValue *k = gkey(n);
- if (ttisshrstring(k) && eqshrstr(tsvalue(k), key))
- return gval(n); /* that's it */
- else {
- int nx = gnext(n);
- if (nx == 0)
- return luaO_nilobject; /* not found */
- n += nx;
- }
- }
-}
-
-
-/*
-** "Generic" get version. (Not that generic: not valid for integers,
-** which may be in array part, nor for floats with integral values.)
-*/
-static const TValue *getgeneric (Table *t, const TValue *key) {
- Node *n = mainposition(t, key);
+ lua_assert(key->tt == LUA_VSHRSTR);
for (;;) { /* check whether 'key' is somewhere in the chain */
- if (luaV_rawequalobj(gkey(n), key))
+ if (keyisshrstr(n) && eqshrstr(keystrval(n), key))
return gval(n); /* that's it */
else {
int nx = gnext(n);
if (nx == 0)
- return luaO_nilobject; /* not found */
+ return &absentkey; /* not found */
n += nx;
}
}
@@ -554,12 +770,12 @@ static const TValue *getgeneric (Table *t, const TValue *key) {
const TValue *luaH_getstr (Table *t, TString *key) {
- if (key->tt == LUA_TSHRSTR)
+ if (key->tt == LUA_VSHRSTR)
return luaH_getshortstr(t, key);
else { /* for long strings, use generic case */
TValue ko;
setsvalue(cast(lua_State *, NULL), &ko, key);
- return getgeneric(t, &ko);
+ return getgeneric(t, &ko, 0);
}
}
@@ -568,66 +784,102 @@ const TValue *luaH_getstr (Table *t, TString *key) {
** main search function
*/
const TValue *luaH_get (Table *t, const TValue *key) {
- switch (ttype(key)) {
- case LUA_TSHRSTR: return luaH_getshortstr(t, tsvalue(key));
- case LUA_TNUMINT: return luaH_getint(t, ivalue(key));
- case LUA_TNIL: return luaO_nilobject;
- case LUA_TNUMFLT: {
+ switch (ttypetag(key)) {
+ case LUA_VSHRSTR: return luaH_getshortstr(t, tsvalue(key));
+ case LUA_VNUMINT: return luaH_getint(t, ivalue(key));
+ case LUA_VNIL: return &absentkey;
+ case LUA_VNUMFLT: {
lua_Integer k;
- if (luaV_tointeger(key, &k, 0)) /* index is int? */
+ if (luaV_flttointeger(fltvalue(key), &k, F2Ieq)) /* integral index? */
return luaH_getint(t, k); /* use specialized version */
/* else... */
} /* FALLTHROUGH */
default:
- return getgeneric(t, key);
+ return getgeneric(t, key, 0);
}
}
/*
+** Finish a raw "set table" operation, where 'slot' is where the value
+** should have been (the result of a previous "get table").
+** Beware: when using this function you probably need to check a GC
+** barrier and invalidate the TM cache.
+*/
+void luaH_finishset (lua_State *L, Table *t, const TValue *key,
+ const TValue *slot, TValue *value) {
+ if (isabstkey(slot))
+ luaH_newkey(L, t, key, value);
+ else
+ setobj2t(L, cast(TValue *, slot), value);
+}
+
+
+/*
** 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_set (lua_State *L, Table *t, const TValue *key, TValue *value) {
+ const TValue *slot = luaH_get(t, key);
+ luaH_finishset(L, t, key, slot, value);
}
void luaH_setint (lua_State *L, Table *t, lua_Integer key, TValue *value) {
const TValue *p = luaH_getint(t, key);
- TValue *cell;
- if (p != luaO_nilobject)
- cell = cast(TValue *, p);
- else {
+ if (isabstkey(p)) {
TValue k;
setivalue(&k, key);
- cell = luaH_newkey(L, t, &k);
+ luaH_newkey(L, t, &k, value);
}
- setobj2t(L, cell, value);
+ else
+ setobj2t(L, cast(TValue *, p), 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;
- if (j > cast(unsigned int, MAX_INT)/2) { /* overflow? */
- /* table was built with bad purposes: resort to linear search */
- i = 1;
- while (!ttisnil(luaH_getint(t, i))) i++;
- return i - 1;
+/*
+** Try to find a boundary in the hash part of table 't'. From the
+** caller, we know that 'j' is zero or present and that 'j + 1' is
+** present. We want to find a larger key that is absent from the
+** table, so that we can do a binary search between the two keys to
+** find a boundary. We keep doubling 'j' until we get an absent index.
+** If the doubling would overflow, we try LUA_MAXINTEGER. If it is
+** absent, we are ready for the binary search. ('j', being max integer,
+** is larger or equal to 'i', but it cannot be equal because it is
+** absent while 'i' is present; so 'j > i'.) Otherwise, 'j' is a
+** boundary. ('j + 1' cannot be a present integer key because it is
+** not a valid integer in Lua.)
+*/
+static lua_Unsigned hash_search (Table *t, lua_Unsigned j) {
+ lua_Unsigned i;
+ if (j == 0) j++; /* the caller ensures 'j + 1' is present */
+ do {
+ i = j; /* 'i' is a present index */
+ if (j <= l_castS2U(LUA_MAXINTEGER) / 2)
+ j *= 2;
+ else {
+ j = LUA_MAXINTEGER;
+ if (isempty(luaH_getint(t, j))) /* t[j] not present? */
+ break; /* 'j' now is an absent index */
+ else /* weird case */
+ return j; /* well, max integer is a boundary... */
}
- j *= 2;
+ } while (!isempty(luaH_getint(t, j))); /* repeat until an absent t[j] */
+ /* i < j && t[i] present && t[j] absent */
+ while (j - i > 1u) { /* do a binary search between them */
+ lua_Unsigned m = (i + j) / 2;
+ if (isempty(luaH_getint(t, m))) j = m;
+ else i = m;
}
- /* 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;
+ return i;
+}
+
+
+static unsigned int binsearch (const TValue *array, unsigned int i,
+ unsigned int j) {
+ while (j - i > 1u) { /* binary search */
+ unsigned int m = (i + j) / 2;
+ if (isempty(&array[m - 1])) j = m;
else i = m;
}
return i;
@@ -635,33 +887,92 @@ static int unbound_search (Table *t, unsigned int j) {
/*
-** 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).
+** Try to find a boundary in table 't'. (A 'boundary' is an integer index
+** such that t[i] is present and t[i+1] is absent, or 0 if t[1] is absent
+** and 'maxinteger' if t[maxinteger] is present.)
+** (In the next explanation, we use Lua indices, that is, with base 1.
+** The code itself uses base 0 when indexing the array part of the table.)
+** The code starts with 'limit = t->alimit', a position in the array
+** part that may be a boundary.
+**
+** (1) If 't[limit]' is empty, there must be a boundary before it.
+** As a common case (e.g., after 't[#t]=nil'), check whether 'limit-1'
+** is present. If so, it is a boundary. Otherwise, do a binary search
+** between 0 and limit to find a boundary. In both cases, try to
+** use this boundary as the new 'alimit', as a hint for the next call.
+**
+** (2) If 't[limit]' is not empty and the array has more elements
+** after 'limit', try to find a boundary there. Again, try first
+** the special case (which should be quite frequent) where 'limit+1'
+** is empty, so that 'limit' is a boundary. Otherwise, check the
+** last element of the array part. If it is empty, there must be a
+** boundary between the old limit (present) and the last element
+** (absent), which is found with a binary search. (This boundary always
+** can be a new limit.)
+**
+** (3) The last case is when there are no elements in the array part
+** (limit == 0) or its last element (the new limit) is present.
+** In this case, must check the hash part. If there is no hash part
+** or 'limit+1' is absent, 'limit' is a boundary. Otherwise, call
+** 'hash_search' to find a boundary in the hash part of the table.
+** (In those cases, the boundary is not inside the array part, and
+** therefore cannot be used as a new limit.)
*/
-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;
+lua_Unsigned luaH_getn (Table *t) {
+ unsigned int limit = t->alimit;
+ if (limit > 0 && isempty(&t->array[limit - 1])) { /* (1)? */
+ /* there must be a boundary before 'limit' */
+ if (limit >= 2 && !isempty(&t->array[limit - 2])) {
+ /* 'limit - 1' is a boundary; can it be a new limit? */
+ if (ispow2realasize(t) && !ispow2(limit - 1)) {
+ t->alimit = limit - 1;
+ setnorealasize(t); /* now 'alimit' is not the real size */
+ }
+ return limit - 1;
}
- return i;
+ else { /* must search for a boundary in [0, limit] */
+ unsigned int boundary = binsearch(t->array, 0, limit);
+ /* can this boundary represent the real size of the array? */
+ if (ispow2realasize(t) && boundary > luaH_realasize(t) / 2) {
+ t->alimit = boundary; /* use it as the new limit */
+ setnorealasize(t);
+ }
+ return boundary;
+ }
+ }
+ /* 'limit' is zero or present in table */
+ if (!limitequalsasize(t)) { /* (2)? */
+ /* 'limit' > 0 and array has more elements after 'limit' */
+ if (isempty(&t->array[limit])) /* 'limit + 1' is empty? */
+ return limit; /* this is the boundary */
+ /* else, try last element in the array */
+ limit = luaH_realasize(t);
+ if (isempty(&t->array[limit - 1])) { /* empty? */
+ /* there must be a boundary in the array after old limit,
+ and it must be a valid new limit */
+ unsigned int boundary = binsearch(t->array, t->alimit, limit);
+ t->alimit = boundary;
+ return boundary;
+ }
+ /* else, new limit is present in the table; check the hash part */
}
- /* else must find a boundary in hash part */
- else if (isdummy(t)) /* hash part is empty? */
- return j; /* that is easy... */
- else return unbound_search(t, j);
+ /* (3) 'limit' is the last element and either is zero or present in table */
+ lua_assert(limit == luaH_realasize(t) &&
+ (limit == 0 || !isempty(&t->array[limit - 1])));
+ if (isdummy(t) || isempty(luaH_getint(t, cast(lua_Integer, limit + 1))))
+ return limit; /* 'limit + 1' is absent */
+ else /* 'limit + 1' is also present */
+ return hash_search(t, limit);
}
#if defined(LUA_DEBUG)
+/* export these functions for the test library */
+
Node *luaH_mainposition (const Table *t, const TValue *key) {
- return mainposition(t, key);
+ return mainpositionTV(t, key);
}
int luaH_isdummy (const Table *t) { return isdummy(t); }