better implementation for list "for"

This commit is contained in:
Roberto Ierusalimschy
2001-01-29 11:14:49 -02:00
parent ca1f28b829
commit caf01b5bfa
5 changed files with 39 additions and 20 deletions

View File

@@ -1,5 +1,5 @@
/* /*
** $Id: lcode.c,v 1.56 2001/01/15 16:13:24 roberto Exp roberto $ ** $Id: lcode.c,v 1.57 2001/01/19 13:20:30 roberto Exp roberto $
** Code generator for Lua ** Code generator for Lua
** See Copyright Notice in lua.h ** See Copyright Notice in lua.h
*/ */
@@ -698,8 +698,8 @@ const OpProperties luaK_opproperties[NUM_OPCODES] = {
{iO, 0, 0}, /* OP_PUSHNILJMP */ {iO, 0, 0}, /* OP_PUSHNILJMP */
{iS, 0, 0}, /* OP_FORPREP */ {iS, 0, 0}, /* OP_FORPREP */
{iS, 0, 3}, /* OP_FORLOOP */ {iS, 0, 3}, /* OP_FORLOOP */
{iS, 2, 0}, /* OP_LFORPREP */ {iS, 3, 0}, /* OP_LFORPREP */
{iS, 0, 3}, /* OP_LFORLOOP */ {iS, 0, 4}, /* OP_LFORLOOP */
{iAB, VD, 0} /* OP_CLOSURE */ {iAB, VD, 0} /* OP_CLOSURE */
}; };

View File

@@ -1,5 +1,5 @@
/* /*
** $Id: lparser.c,v 1.124 2001/01/15 16:13:24 roberto Exp roberto $ ** $Id: lparser.c,v 1.125 2001/01/19 13:20:30 roberto Exp roberto $
** LL(1) Parser and code generator for Lua ** LL(1) Parser and code generator for Lua
** See Copyright Notice in lua.h ** See Copyright Notice in lua.h
*/ */
@@ -890,9 +890,10 @@ static void forlist (LexState *ls, TString *indexname) {
next(ls); /* skip `in' */ next(ls); /* skip `in' */
exp1(ls); /* table */ exp1(ls); /* table */
new_localvarstr(ls, "(table)", 0); new_localvarstr(ls, "(table)", 0);
new_localvar(ls, indexname, 1); new_localvarstr(ls, "(index)", 1);
new_localvar(ls, valname, 2); new_localvar(ls, indexname, 2);
forbody(ls, 3, OP_LFORPREP, OP_LFORLOOP); new_localvar(ls, valname, 3);
forbody(ls, 4, OP_LFORPREP, OP_LFORLOOP);
} }

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@@ -1,5 +1,5 @@
/* /*
** $Id: ltable.c,v 1.69 2001/01/26 14:16:35 roberto Exp roberto $ ** $Id: ltable.c,v 1.70 2001/01/26 15:58:50 roberto Exp roberto $
** Lua tables (hash) ** Lua tables (hash)
** See Copyright Notice in lua.h ** See Copyright Notice in lua.h
*/ */
@@ -72,6 +72,15 @@ Node *luaH_next (lua_State *L, Hash *t, const TObject *key) {
} }
int luaH_nexti (Hash *t, int i) {
for (i++; i<t->size; i++) {
if (ttype(val(node(t, i))) != LUA_TNIL) /* a non-nil value? */
return i;
}
return -1; /* no more elements */
}
static void setnodevector (lua_State *L, Hash *t, luint32 size) { static void setnodevector (lua_State *L, Hash *t, luint32 size) {
int i; int i;
if (size > MAX_INT) if (size > MAX_INT)

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@@ -1,5 +1,5 @@
/* /*
** $Id: ltable.h,v 1.28 2001/01/26 13:18:00 roberto Exp roberto $ ** $Id: ltable.h,v 1.29 2001/01/26 14:16:35 roberto Exp roberto $
** Lua tables (hash) ** Lua tables (hash)
** See Copyright Notice in lua.h ** See Copyright Notice in lua.h
*/ */
@@ -21,7 +21,8 @@
Hash *luaH_new (lua_State *L, int nhash); Hash *luaH_new (lua_State *L, int nhash);
void luaH_free (lua_State *L, Hash *t); void luaH_free (lua_State *L, Hash *t);
TObject *luaH_set (lua_State *L, Hash *t, const TObject *key); TObject *luaH_set (lua_State *L, Hash *t, const TObject *key);
Node * luaH_next (lua_State *L, Hash *t, const TObject *r); Node *luaH_next (lua_State *L, Hash *t, const TObject *r);
int luaH_nexti (Hash *t, int i);
TObject *luaH_setnum (lua_State *L, Hash *t, lua_Number key); TObject *luaH_setnum (lua_State *L, Hash *t, lua_Number key);
TObject *luaH_setstr (lua_State *L, Hash *t, TString *key); TObject *luaH_setstr (lua_State *L, Hash *t, TString *key);

28
lvm.c
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@@ -1,5 +1,5 @@
/* /*
** $Id: lvm.c,v 1.157 2001/01/24 16:20:54 roberto Exp roberto $ ** $Id: lvm.c,v 1.158 2001/01/26 18:43:22 roberto Exp roberto $
** Lua virtual machine ** Lua virtual machine
** See Copyright Notice in lua.h ** See Copyright Notice in lua.h
*/ */
@@ -644,28 +644,36 @@ StkId luaV_execute (lua_State *L, const Closure *cl, StkId base) {
break; break;
} }
case OP_LFORPREP: { case OP_LFORPREP: {
Node *node; int n;
Hash *t;
if (ttype(top-1) != LUA_TTABLE) if (ttype(top-1) != LUA_TTABLE)
luaD_error(L, "`for' table must be a table"); luaD_error(L, "`for' table must be a table");
node = luaH_next(L, hvalue(top-1), &luaO_nilobject); t = hvalue(top-1);
if (node == NULL) { /* `empty' loop? */ n = luaH_nexti(t, -1);
if (n == -1) { /* `empty' loop? */
top--; /* remove table */ top--; /* remove table */
dojump(pc, i); /* jump to loop end */ dojump(pc, i); /* jump to loop end */
} }
else { else {
top += 2; /* index,value */ Node *node = node(t, n);
top += 3; /* index,key,value */
setnvalue(top-3, n); /* index */
setobj(top-2, key(node)); setobj(top-2, key(node));
setobj(top-1, val(node)); setobj(top-1, val(node));
} }
break; break;
} }
case OP_LFORLOOP: { case OP_LFORLOOP: {
Node *node; Hash *t = hvalue(top-4);
lua_assert(ttype(top-3) == LUA_TTABLE); int n = (int)nvalue(top-3);
node = luaH_next(L, hvalue(top-3), top-2); lua_assert(ttype(top-3) == LUA_TNUMBER);
if (node == NULL) /* end loop? */ lua_assert(ttype(top-4) == LUA_TTABLE);
top -= 3; /* remove table, key, and value */ n = luaH_nexti(t, n);
if (n == -1) /* end loop? */
top -= 4; /* remove table, index, key, and value */
else { else {
Node *node = node(t, n);
setnvalue(top-3, n); /* index */
setobj(top-2, key(node)); setobj(top-2, key(node));
setobj(top-1, val(node)); setobj(top-1, val(node));
dojump(pc, i); /* repeat loop */ dojump(pc, i); /* repeat loop */