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@@ -1,5 +1,5 @@
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/*
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-** $Id: ltable.c,v 2.118 2016/11/07 12:38:35 roberto Exp $
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+** $Id: ltable.c $
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** Lua tables (hash)
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** See Copyright Notice in lua.h
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*/
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@@ -40,21 +40,34 @@
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/*
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-** Maximum size of array part (MAXASIZE) is 2^MAXABITS. MAXABITS is
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-** the largest integer such that MAXASIZE fits in an unsigned int.
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+** MAXABITS is the largest integer such that MAXASIZE fits in an
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+** unsigned int.
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*/
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#define MAXABITS cast_int(sizeof(int) * CHAR_BIT - 1)
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-#define MAXASIZE (1u << MAXABITS)
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+
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/*
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-** Maximum size of hash part is 2^MAXHBITS. MAXHBITS is the largest
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-** integer such that 2^MAXHBITS fits in a signed int. (Note that the
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-** maximum number of elements in a table, 2^MAXABITS + 2^MAXHBITS, still
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-** fits comfortably in an unsigned int.)
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+** MAXASIZE is the maximum size of the array part. It is the minimum
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+** between 2^MAXABITS and the maximum size that, measured in bytes,
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+** fits in a 'size_t'.
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+*/
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+#define MAXASIZE luaM_limitN(1u << MAXABITS, TValue)
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+
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+/*
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+** MAXHBITS is the largest integer such that 2^MAXHBITS fits in a
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+** signed int.
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*/
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#define MAXHBITS (MAXABITS - 1)
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+/*
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+** MAXHSIZE is the maximum size of the hash part. It is the minimum
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+** between 2^MAXHBITS and the maximum size such that, measured in bytes,
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+** it fits in a 'size_t'.
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+*/
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+#define MAXHSIZE luaM_limitN(1u << MAXHBITS, Node)
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+
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+
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#define hashpow2(t,n) (gnode(t, lmod((n), sizenode(t))))
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#define hashstr(t,str) hashpow2(t, (str)->hash)
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@@ -75,11 +88,15 @@
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#define dummynode (&dummynode_)
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static const Node dummynode_ = {
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- {NILCONSTANT}, /* value */
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- {{NILCONSTANT, 0}} /* key */
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+ {{NULL}, LUA_VEMPTY, /* value's value and type */
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+ LUA_VNIL, 0, {NULL}} /* key type, next, and key value */
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};
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+static const TValue absentkey = {ABSTKEYCONSTANT};
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+
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+
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+
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/*
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** Hash for floating-point numbers.
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** The main computation should be just
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@@ -103,51 +120,176 @@ static int l_hashfloat (lua_Number n) {
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return 0;
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}
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else { /* normal case */
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- unsigned int u = cast(unsigned int, i) + cast(unsigned int, ni);
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- return cast_int(u <= cast(unsigned int, INT_MAX) ? u : ~u);
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+ unsigned int u = cast_uint(i) + cast_uint(ni);
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+ return cast_int(u <= cast_uint(INT_MAX) ? u : ~u);
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}
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}
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#endif
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/*
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-** returns the 'main' position of an element in a table (that is, the index
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-** of its hash value)
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-*/
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-static Node *mainposition (const Table *t, const TValue *key) {
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- switch (ttype(key)) {
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- case LUA_TNUMINT:
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- return hashint(t, ivalue(key));
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- case LUA_TNUMFLT:
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- return hashmod(t, l_hashfloat(fltvalue(key)));
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- case LUA_TSHRSTR:
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- return hashstr(t, tsvalue(key));
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- case LUA_TLNGSTR:
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- return hashpow2(t, luaS_hashlongstr(tsvalue(key)));
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- case LUA_TBOOLEAN:
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- return hashboolean(t, bvalue(key));
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- case LUA_TLIGHTUSERDATA:
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- return hashpointer(t, pvalue(key));
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- case LUA_TLCF:
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- return hashpointer(t, fvalue(key));
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+** returns the 'main' position of an element in a table (that is,
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+** the index of its hash value). The key comes broken (tag in 'ktt'
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+** and value in 'vkl') so that we can call it on keys inserted into
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+** nodes.
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+*/
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+static Node *mainposition (const Table *t, int ktt, const Value *kvl) {
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+ switch (withvariant(ktt)) {
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+ case LUA_VNUMINT:
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+ return hashint(t, ivalueraw(*kvl));
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+ case LUA_VNUMFLT:
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+ return hashmod(t, l_hashfloat(fltvalueraw(*kvl)));
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+ case LUA_VSHRSTR:
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+ return hashstr(t, tsvalueraw(*kvl));
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+ case LUA_VLNGSTR:
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+ return hashpow2(t, luaS_hashlongstr(tsvalueraw(*kvl)));
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+ case LUA_VFALSE:
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+ return hashboolean(t, 0);
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+ case LUA_VTRUE:
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+ return hashboolean(t, 1);
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+ case LUA_VLIGHTUSERDATA:
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+ return hashpointer(t, pvalueraw(*kvl));
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+ case LUA_VLCF:
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+ return hashpointer(t, fvalueraw(*kvl));
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+ default:
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+ return hashpointer(t, gcvalueraw(*kvl));
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+ }
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+}
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+
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+
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+/*
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+** Returns the main position of an element given as a 'TValue'
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+*/
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+static Node *mainpositionTV (const Table *t, const TValue *key) {
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+ return mainposition(t, rawtt(key), valraw(key));
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+}
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+
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+
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+/*
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+** Check whether key 'k1' is equal to the key in node 'n2'. This
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+** equality is raw, so there are no metamethods. Floats with integer
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+** values have been normalized, so integers cannot be equal to
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+** floats. It is assumed that 'eqshrstr' is simply pointer equality, so
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+** that short strings are handled in the default case.
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+** A true 'deadok' means to accept dead keys as equal to their original
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+** values. All dead keys are compared in the default case, by pointer
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+** identity. (Only collectable objects can produce dead keys.) Note that
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+** dead long strings are also compared by identity.
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+** Once a key is dead, its corresponding value may be collected, and
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+** then another value can be created with the same address. If this
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+** other value is given to 'next', 'equalkey' will signal a false
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+** positive. In a regular traversal, this situation should never happen,
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+** as all keys given to 'next' came from the table itself, and therefore
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+** could not have been collected. Outside a regular traversal, we
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+** have garbage in, garbage out. What is relevant is that this false
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+** positive does not break anything. (In particular, 'next' will return
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+** some other valid item on the table or nil.)
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+*/
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+static int equalkey (const TValue *k1, const Node *n2, int deadok) {
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+ if ((rawtt(k1) != keytt(n2)) && /* not the same variants? */
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+ !(deadok && keyisdead(n2) && iscollectable(k1)))
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+ return 0; /* cannot be same key */
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+ switch (keytt(n2)) {
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+ case LUA_VNIL: case LUA_VFALSE: case LUA_VTRUE:
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+ return 1;
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+ case LUA_VNUMINT:
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+ return (ivalue(k1) == keyival(n2));
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+ case LUA_VNUMFLT:
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+ return luai_numeq(fltvalue(k1), fltvalueraw(keyval(n2)));
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+ case LUA_VLIGHTUSERDATA:
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+ return pvalue(k1) == pvalueraw(keyval(n2));
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+ case LUA_VLCF:
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+ return fvalue(k1) == fvalueraw(keyval(n2));
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+ case ctb(LUA_VLNGSTR):
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+ return luaS_eqlngstr(tsvalue(k1), keystrval(n2));
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default:
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- lua_assert(!ttisdeadkey(key));
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- return hashpointer(t, gcvalue(key));
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+ return gcvalue(k1) == gcvalueraw(keyval(n2));
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}
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}
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/*
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-** returns the index for 'key' if 'key' is an appropriate key to live in
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-** the array part of the table, 0 otherwise.
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+** True if value of 'alimit' is equal to the real size of the array
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+** part of table 't'. (Otherwise, the array part must be larger than
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+** 'alimit'.)
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*/
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-static unsigned int arrayindex (const TValue *key) {
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- if (ttisinteger(key)) {
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- lua_Integer k = ivalue(key);
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- if (0 < k && (lua_Unsigned)k <= MAXASIZE)
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- return cast(unsigned int, k); /* 'key' is an appropriate array index */
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+#define limitequalsasize(t) (isrealasize(t) || ispow2((t)->alimit))
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+
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+
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+/*
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+** Returns the real size of the 'array' array
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+*/
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+LUAI_FUNC unsigned int luaH_realasize (const Table *t) {
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+ if (limitequalsasize(t))
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+ return t->alimit; /* this is the size */
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+ else {
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+ unsigned int size = t->alimit;
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+ /* compute the smallest power of 2 not smaller than 'n' */
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+ size |= (size >> 1);
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+ size |= (size >> 2);
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+ size |= (size >> 4);
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+ size |= (size >> 8);
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+ size |= (size >> 16);
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+#if (UINT_MAX >> 30) > 3
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+ size |= (size >> 32); /* unsigned int has more than 32 bits */
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+#endif
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+ size++;
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+ lua_assert(ispow2(size) && size/2 < t->alimit && t->alimit < size);
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+ return size;
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}
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- return 0; /* 'key' did not match some condition */
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+}
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+
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+
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+/*
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+** Check whether real size of the array is a power of 2.
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+** (If it is not, 'alimit' cannot be changed to any other value
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+** without changing the real size.)
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+*/
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+static int ispow2realasize (const Table *t) {
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+ return (!isrealasize(t) || ispow2(t->alimit));
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+}
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+
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+
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+static unsigned int setlimittosize (Table *t) {
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+ t->alimit = luaH_realasize(t);
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+ setrealasize(t);
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+ return t->alimit;
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+}
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+
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+
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+#define limitasasize(t) check_exp(isrealasize(t), t->alimit)
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+
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+
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+
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+/*
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+** "Generic" get version. (Not that generic: not valid for integers,
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+** which may be in array part, nor for floats with integral values.)
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+** See explanation about 'deadok' in function 'equalkey'.
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+*/
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+static const TValue *getgeneric (Table *t, const TValue *key, int deadok) {
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+ Node *n = mainpositionTV(t, key);
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+ for (;;) { /* check whether 'key' is somewhere in the chain */
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+ if (equalkey(key, n, deadok))
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+ return gval(n); /* that's it */
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+ else {
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+ int nx = gnext(n);
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+ if (nx == 0)
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+ return &absentkey; /* not found */
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+ n += nx;
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+ }
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+ }
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+}
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+
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+
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+/*
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+** returns the index for 'k' if 'k' is an appropriate key to live in
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+** the array part of a table, 0 otherwise.
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+*/
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+static unsigned int arrayindex (lua_Integer k) {
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+ if (l_castS2U(k) - 1u < MAXASIZE) /* 'k' in [1, MAXASIZE]? */
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+ return cast_uint(k); /* 'key' is an appropriate array index */
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+ else
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+ return 0;
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}
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@@ -156,46 +298,39 @@ static unsigned int arrayindex (const TValue *key) {
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** elements in the array part, then elements in the hash part. The
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** beginning of a traversal is signaled by 0.
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*/
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-static unsigned int findindex (lua_State *L, Table *t, StkId key) {
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+static unsigned int findindex (lua_State *L, Table *t, TValue *key,
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+ unsigned int asize) {
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unsigned int i;
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if (ttisnil(key)) return 0; /* first iteration */
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- i = arrayindex(key);
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- if (i != 0 && i <= t->sizearray) /* is 'key' inside array part? */
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+ i = ttisinteger(key) ? arrayindex(ivalue(key)) : 0;
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+ if (i - 1u < asize) /* is 'key' inside array part? */
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return i; /* yes; that's the index */
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else {
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- int nx;
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- Node *n = mainposition(t, key);
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- for (;;) { /* check whether 'key' is somewhere in the chain */
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- /* key may be dead already, but it is ok to use it in 'next' */
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- if (luaV_rawequalobj(gkey(n), key) ||
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- (ttisdeadkey(gkey(n)) && iscollectable(key) &&
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- deadvalue(gkey(n)) == gcvalue(key))) {
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- i = cast_int(n - gnode(t, 0)); /* key index in hash table */
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- /* hash elements are numbered after array ones */
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- return (i + 1) + t->sizearray;
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- }
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- nx = gnext(n);
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- if (nx == 0)
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- luaG_runerror(L, "invalid key to 'next'"); /* key not found */
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- else n += nx;
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- }
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+ const TValue *n = getgeneric(t, key, 1);
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+ if (unlikely(isabstkey(n)))
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+ luaG_runerror(L, "invalid key to 'next'"); /* key not found */
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+ i = cast_int(nodefromval(n) - gnode(t, 0)); /* key index in hash table */
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+ /* hash elements are numbered after array ones */
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+ return (i + 1) + asize;
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}
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}
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int luaH_next (lua_State *L, Table *t, StkId key) {
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- unsigned int i = findindex(L, t, key); /* find original element */
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- for (; i < t->sizearray; i++) { /* try first array part */
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- if (!ttisnil(&t->array[i])) { /* a non-nil value? */
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- setivalue(key, i + 1);
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- setobj2s(L, key+1, &t->array[i]);
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+ unsigned int asize = luaH_realasize(t);
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+ unsigned int i = findindex(L, t, s2v(key), asize); /* find original key */
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+ for (; i < asize; i++) { /* try first array part */
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+ if (!isempty(&t->array[i])) { /* a non-empty entry? */
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+ setivalue(s2v(key), i + 1);
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+ setobj2s(L, key + 1, &t->array[i]);
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return 1;
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}
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}
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- for (i -= t->sizearray; cast_int(i) < sizenode(t); i++) { /* hash part */
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- if (!ttisnil(gval(gnode(t, i)))) { /* a non-nil value? */
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- setobj2s(L, key, gkey(gnode(t, i)));
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- setobj2s(L, key+1, gval(gnode(t, i)));
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+ for (i -= asize; cast_int(i) < sizenode(t); i++) { /* hash part */
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+ if (!isempty(gval(gnode(t, i)))) { /* a non-empty entry? */
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+ Node *n = gnode(t, i);
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+ getnodekey(L, s2v(key), n);
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+ setobj2s(L, key + 1, gval(n));
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return 1;
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}
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}
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@@ -203,6 +338,12 @@ int luaH_next (lua_State *L, Table *t, StkId key) {
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}
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+static void freehash (lua_State *L, Table *t) {
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+ if (!isdummy(t))
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+ luaM_freearray(L, t->node, cast_sizet(sizenode(t)));
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+}
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+
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+
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/*
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** {=============================================================
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** Rehash
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@@ -214,7 +355,8 @@ int luaH_next (lua_State *L, Table *t, StkId key) {
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** "count array" where 'nums[i]' is the number of integers in the table
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** between 2^(i - 1) + 1 and 2^i. 'pna' enters with the total number of
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** integer keys in the table and leaves with the number of keys that
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-** will go to the array part; return the optimal size.
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+** will go to the array part; return the optimal size. (The condition
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+** 'twotoi > 0' in the for loop stops the loop if 'twotoi' overflows.)
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*/
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static unsigned int computesizes (unsigned int nums[], unsigned int *pna) {
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int i;
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@@ -223,13 +365,13 @@ static unsigned int computesizes (unsigned int nums[], unsigned int *pna) {
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unsigned int na = 0; /* number of elements to go to array part */
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unsigned int optimal = 0; /* optimal size for array part */
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/* loop while keys can fill more than half of total size */
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- for (i = 0, twotoi = 1; *pna > twotoi / 2; i++, twotoi *= 2) {
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- if (nums[i] > 0) {
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- a += nums[i];
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|
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- 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 +380,7 @@ 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 +401,19 @@ 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 +429,9 @@ 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 +440,13 @@ 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 +456,15 @@ 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 +472,88 @@ 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);
|
|
|
+ setobjt2t(L, 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 (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 +572,13 @@ 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 +594,20 @@ 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 +616,7 @@ 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;
|
|
|
}
|
|
|
}
|
|
@@ -442,18 +635,20 @@ static Node *getfreepos (Table *t) {
|
|
|
TValue *luaH_newkey (lua_State *L, Table *t, const TValue *key) {
|
|
|
Node *mp;
|
|
|
TValue aux;
|
|
|
- if (ttisnil(key)) luaG_runerror(L, "table index is nil");
|
|
|
+ if (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 (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? */
|
|
|
+ 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? */
|
|
@@ -462,7 +657,7 @@ TValue *luaH_newkey (lua_State *L, Table *t, const TValue *key) {
|
|
|
return luaH_set(L, t, key); /* insert key into grown table */
|
|
|
}
|
|
|
lua_assert(!isdummy(t));
|
|
|
- othern = mainposition(t, gkey(mp));
|
|
|
+ othern = mainposition(t, keytt(mp), &keyval(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 +668,7 @@ 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 +679,34 @@ 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)));
|
|
|
+ setnodekey(L, mp, key);
|
|
|
+ luaC_barrierback(L, obj2gco(t), key);
|
|
|
+ lua_assert(isempty(gval(mp)));
|
|
|
return gval(mp);
|
|
|
}
|
|
|
|
|
|
|
|
|
/*
|
|
|
-** 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 +714,7 @@ const TValue *luaH_getint (Table *t, lua_Integer key) {
|
|
|
n += nx;
|
|
|
}
|
|
|
}
|
|
|
- return luaO_nilobject;
|
|
|
+ return &absentkey;
|
|
|
}
|
|
|
}
|
|
|
|
|
@@ -519,34 +724,14 @@ 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);
|
|
|
+ lua_assert(key->tt == LUA_VSHRSTR);
|
|
|
for (;;) { /* check whether 'key' is somewhere in the chain */
|
|
|
- const TValue *k = gkey(n);
|
|
|
- if (ttisshrstring(k) && eqshrstr(tsvalue(k), 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 */
|
|
|
- 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);
|
|
|
- for (;;) { /* check whether 'key' is somewhere in the chain */
|
|
|
- if (luaV_rawequalobj(gkey(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 +739,12 @@ 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);
|
|
|
}
|
|
|
}
|
|
|
|
|
@@ -568,18 +753,18 @@ 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);
|
|
|
}
|
|
|
}
|
|
|
|
|
@@ -590,7 +775,7 @@ const TValue *luaH_get (Table *t, const TValue *key) {
|
|
|
*/
|
|
|
TValue *luaH_set (lua_State *L, Table *t, const TValue *key) {
|
|
|
const TValue *p = luaH_get(t, key);
|
|
|
- if (p != luaO_nilobject)
|
|
|
+ if (!isabstkey(p))
|
|
|
return cast(TValue *, p);
|
|
|
else return luaH_newkey(L, t, key);
|
|
|
}
|
|
@@ -599,7 +784,7 @@ TValue *luaH_set (lua_State *L, Table *t, const TValue *key) {
|
|
|
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)
|
|
|
+ if (!isabstkey(p))
|
|
|
cell = cast(TValue *, p);
|
|
|
else {
|
|
|
TValue k;
|
|
@@ -610,24 +795,49 @@ void luaH_setint (lua_State *L, Table *t, lua_Integer key, TValue *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 +845,92 @@ 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;
|
|
|
+ }
|
|
|
+ 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;
|
|
|
}
|
|
|
- return i;
|
|
|
+ /* 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); }
|