nik/lush
1
1
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Lua closures are cached for reuse

Browse Source
This commit is contained in:
Roberto Ierusalimschy
2010-06-04 10:25:10 -03:00
parent 545f43065f
commit 575074fd85
5 changed files with 114 additions and 36 deletions
Download Patch File Download Diff File Expand all files Collapse all files

68
lvm.c
View File

@@ -1,5 +1,5 @@
/*
** $Id: lvm.c,v 2.119 2010/05/12 20:40:35 roberto Exp roberto $
** $Id: lvm.c,v 2.120 2010/05/13 19:53:05 roberto Exp roberto $
** Lua virtual machine
** See Copyright Notice in lua.h
*/
@@ -136,7 +136,7 @@ void luaV_settable (lua_State *L, const TValue *t, TValue *key, StkId val) {
if (!ttisnil(oldval) || /* result is not nil? */
(tm = fasttm(L, h->metatable, TM_NEWINDEX)) == NULL) { /* or no TM? */
setobj2t(L, oldval, val);
luaC_barriert(L, h, val);
luaC_barrierback(L, obj2gco(h), val);
return;
}
/* else will try the tag method */
@@ -345,6 +345,49 @@ void luaV_arith (lua_State *L, StkId ra, const TValue *rb,
}
/*
** check whether cached closure in prototype 'p' may be reused, that is,
** whether there is a cached closure with the same upvalues needed by
** new closure to be created.
*/
static Closure *getcached (Proto *p, UpVal **encup, StkId base) {
Closure *c = p->cache;
if (c != NULL) { /* is there a cached closure? */
int nup = p->sizeupvalues;
Upvaldesc *uv = p->upvalues;
int i;
for (i = 0; i < nup; i++) { /* check whether it has right upvalues */
TValue *v = uv[i].instack ? base + uv[i].idx : encup[uv[i].idx]->v;
if (c->l.upvals[i]->v != v)
return NULL; /* wrong upvalue; cannot reuse closure */
}
}
return c; /* return cached closure (or NULL if no cached closure) */
}
/*
** create a new Lua closure, push it in the stack, and initialize
** its upvalues
*/
static void pushclosure (lua_State *L, Proto *p, UpVal **encup, StkId base,
StkId ra) {
int nup = p->sizeupvalues;
Upvaldesc *uv = p->upvalues;
int i;
Closure *ncl = luaF_newLclosure(L, p);
setclvalue(L, ra, ncl); /* anchor new closure in stack */
for (i = 0; i < nup; i++) { /* fill in its upvalues */
if (uv[i].instack) /* upvalue refers to local variable? */
ncl->l.upvals[i] = luaF_findupval(L, base + uv[i].idx);
else /* get upvalue from enclosing function */
ncl->l.upvals[i] = encup[uv[i].idx];
}
p->cache = ncl; /* save it on cache, so it can be reused */
luaC_barrierproto(L, obj2gco(p));
}
/*
** finish execution of an opcode interrupted by an yield
*/
@@ -721,7 +764,7 @@ void luaV_execute (lua_State *L) {
for (; n > 0; n--) {
TValue *val = ra+n;
setobj2t(L, luaH_setint(L, h, last--), val);
luaC_barriert(L, h, val);
luaC_barrierback(L, obj2gco(h), val);
}
L->top = ci->top; /* correct top (in case of previous open call) */
)
@@ -729,19 +772,12 @@ void luaV_execute (lua_State *L) {
luaF_close(L, ra);
)
vmcase(OP_CLOSURE,
Proto *p = cl->p->p[GETARG_Bx(i)]; /* prototype for new closure */
int nup = p->sizeupvalues;
Closure *ncl = luaF_newLclosure(L, nup);
Upvaldesc *uv = p->upvalues;
int j;
ncl->l.p = p;
setclvalue(L, ra, ncl); /* anchor new closure in stack */
for (j = 0; j < nup; j++) { /* fill in upvalues */
if (uv[j].instack) /* upvalue refers to local variable? */
ncl->l.upvals[j] = luaF_findupval(L, base + uv[j].idx);
else /* get upvalue from enclosing function */
ncl->l.upvals[j] = cl->upvals[uv[j].idx];
}
Proto *p = cl->p->p[GETARG_Bx(i)];
Closure *ncl = getcached(p, cl->upvals, base); /* cached closure */
if (ncl == NULL) /* no match? */
pushclosure(L, p, cl->upvals, base, ra); /* create a new one */
else
setclvalue(L, ra, ncl); /* push cashed closure */
checkGC(L);
)
vmcase(OP_VARARG,