diff --git a/lgc.c b/lgc.c index 6fd41d34..72984d2a 100644 --- a/lgc.c +++ b/lgc.c @@ -1,5 +1,5 @@ /* -** $Id: lgc.c,v 1.155 2002/11/07 15:37:10 roberto Exp roberto $ +** $Id: lgc.c,v 1.156 2002/11/11 11:52:43 roberto Exp roberto $ ** Garbage Collector ** See Copyright Notice in lua.h */ @@ -21,11 +21,11 @@ typedef struct GCState { - Table *tmark; /* list of marked tables to be visited */ - Table *wk; /* list of visited key-weak tables (to be cleared after GC) */ - Table *wv; /* list of visited value-weak tables */ - Table *wkv; /* list of visited key-value weak tables */ - lua_State *L; + GCObject *tmark; /* list of marked objects to be traversed */ + GCObject *wk; /* list of traversed key-weak tables (to be cleared) */ + GCObject *wv; /* list of traversed value-weak tables */ + GCObject *wkv; /* list of traversed key-value weak tables */ + global_State *G; } GCState; @@ -47,8 +47,6 @@ typedef struct GCState { #define markfinalized(u) resetbit((u)->uv.marked, 1) -static void reallymarkobject (GCState *st, GCObject *o); - #define markobject(st,o) { checkconsistency(o); \ if (iscollectable(o) && !ismarked(gcvalue(o))) reallymarkobject(st,gcvalue(o)); } @@ -56,30 +54,138 @@ static void reallymarkobject (GCState *st, GCObject *o); if (iscollectable(o) && !ismarked(gcvalue(o)) && (c)) \ reallymarkobject(st,gcvalue(o)); } -#define marktable(st,t) { if (!ismarked(cast(GCObject *, t))) \ - reallymarkobject(st, cast(GCObject *, (t))); } +#define markvalue(st,t) { if (!ismarked(valtogco(t))) \ + reallymarkobject(st, valtogco(t)); } -static void markproto (Proto *f) { - if (!f->marked) { - int i; - f->marked = 1; - strmark(f->source); - for (i=0; isizek; i++) { - if (ttisstring(f->k+i)) - strmark(tsvalue(f->k+i)); + +static void reallymarkobject (GCState *st, GCObject *o) { + lua_assert(!ismarked(o)); + setbit(o->gch.marked, 0); /* mark object */ + switch (o->gch.tt) { + case LUA_TUSERDATA: { + markvalue(st, gcotou(o)->uv.metatable); + break; } - for (i=0; isizep; i++) - markproto(f->p[i]); - for (i=0; isizelocvars; i++) /* mark local-variable names */ - strmark(f->locvars[i].varname); + case LUA_TFUNCTION: { + gcotocl(o)->c.gclist = st->tmark; + st->tmark = o; + break; + } + case LUA_TTABLE: { + gcotoh(o)->gclist = st->tmark; + st->tmark = o; + break; + } + case LUA_TTHREAD: { + gcototh(o)->gclist = st->tmark; + st->tmark = o; + break; + } + case LUA_TPROTO: { + gcotop(o)->gclist = st->tmark; + st->tmark = o; + break; + } + default: lua_assert(o->gch.tt == LUA_TSTRING); } +} + + +static void marktmu (GCState *st) { + GCObject *u; + for (u = st->G->tmudata; u; u = u->gch.next) { + unmark(u); /* may be marked, if left from previous GC */ + reallymarkobject(st, u); + } +} + + +/* move `dead' udata that need finalization to list `tmudata' */ +static void separateudata (lua_State *L) { + GCObject **p = &G(L)->rootudata; + GCObject *curr; + GCObject *collected = NULL; /* to collect udata with gc event */ + GCObject **lastcollected = &collected; + while ((curr = *p) != NULL) { + lua_assert(curr->gch.tt == LUA_TUSERDATA); + if (ismarked(curr) || isfinalized(gcotou(curr))) + p = &curr->gch.next; /* don't bother with them */ + + else if (fasttm(L, gcotou(curr)->uv.metatable, TM_GC) == NULL) { + markfinalized(gcotou(curr)); /* don't need finalization */ + p = &curr->gch.next; + } + else { /* must call its gc method */ + *p = curr->gch.next; + curr->gch.next = NULL; /* link `curr' at the end of `collected' list */ + *lastcollected = curr; + lastcollected = &curr->gch.next; + } + } + /* insert collected udata with gc event into `tmudata' list */ + *lastcollected = G(L)->tmudata; + G(L)->tmudata = collected; +} + + +static void removekey (Node *n) { + setnilvalue(val(n)); /* remove corresponding value ... */ + if (iscollectable(key(n))) + setttype(key(n), LUA_TNONE); /* dead key; remove it */ +} + + +static void traversetable (GCState *st, Table *h) { + int i; + int weakkey = 0; + int weakvalue = 0; + markvalue(st, h->metatable); + lua_assert(h->lsizenode || h->node == st->G->dummynode); + if (h->mode & (WEAKKEY | WEAKVALUE)) { /* weak table? */ + GCObject **weaklist; + weakkey = h->mode & WEAKKEY; + weakvalue = h->mode & WEAKVALUE; + weaklist = (weakkey && weakvalue) ? &st->wkv : + (weakkey) ? &st->wk : + &st->wv; + h->gclist = *weaklist; /* must be cleared after GC, ... */ + *weaklist = valtogco(h); /* ... so put in the appropriate list */ + } + if (!weakvalue) { + i = sizearray(h); + while (i--) + markobject(st, &h->array[i]); + } + i = sizenode(h); + while (i--) { + Node *n = node(h, i); + if (!ttisnil(val(n))) { + lua_assert(!ttisnil(key(n))); + condmarkobject(st, key(n), !weakkey); + condmarkobject(st, val(n), !weakvalue); + } + } +} + + +static void traverseproto (GCState *st, Proto *f) { + int i; + strmark(f->source); + for (i=0; isizek; i++) { + if (ttisstring(f->k+i)) + strmark(tsvalue(f->k+i)); + } + for (i=0; isizep; i++) + markvalue(st, f->p[i]); + for (i=0; isizelocvars; i++) /* mark local-variable names */ + strmark(f->locvars[i].varname); lua_assert(luaG_checkcode(f)); } -static void markclosure (GCState *st, Closure *cl) { +static void traverseclosure (GCState *st, Closure *cl) { if (cl->c.isC) { int i; for (i=0; ic.nupvalues; i++) /* mark its upvalues */ @@ -88,8 +194,8 @@ static void markclosure (GCState *st, Closure *cl) { else { int i; lua_assert(cl->l.nupvalues == cl->l.p->nupvalues); - marktable(st, hvalue(&cl->l.g)); - markproto(cl->l.p); + markvalue(st, hvalue(&cl->l.g)); + markvalue(st, cl->l.p); for (i=0; il.nupvalues; i++) { /* mark its upvalues */ UpVal *u = cl->l.upvals[i]; if (!u->marked) { @@ -111,7 +217,7 @@ static void checkstacksizes (lua_State *L, StkId max) { } -static void markstack (GCState *st, lua_State *L1) { +static void traversestack (GCState *st, lua_State *L1) { StkId o, lim; CallInfo *ci; markobject(st, gt(L1)); @@ -127,110 +233,35 @@ static void markstack (GCState *st, lua_State *L1) { } -static void reallymarkobject (GCState *st, GCObject *o) { - setbit(o->gch.marked, 0); /* mark object */ - switch (o->gch.tt) { - case LUA_TFUNCTION: { - markclosure(st, &o->cl); - break; - } - case LUA_TUSERDATA: { - marktable(st, (&o->u)->uv.metatable); - break; - } - case LUA_TTABLE: { - (&o->h)->gclist = st->tmark; /* chain it for later traversal */ - st->tmark = &o->h; - break; - } - case LUA_TTHREAD: { - markstack(st, &o->th); - break; - } - } -} - - -static void marktmu (GCState *st) { - GCObject *u; - for (u = G(st->L)->tmudata; u; u = u->uv.next) - reallymarkobject(st, u); -} - - -/* move `dead' udata that need finalization to list `tmudata' */ -static void separateudata (lua_State *L) { - GCObject **p = &G(L)->rootudata; - GCObject *curr; - GCObject *collected = NULL; /* to collect udata with gc event */ - GCObject **lastcollected = &collected; - while ((curr = *p) != NULL) { - lua_assert(curr->gch.tt == LUA_TUSERDATA); - if (ismarked(curr) || isfinalized(&curr->u)) - p = &curr->uv.next; /* don't bother with them */ - - else if (fasttm(L, (&curr->u)->uv.metatable, TM_GC) == NULL) { - markfinalized(&curr->u); /* don't need finalization */ - p = &curr->uv.next; - } - else { /* must call its gc method */ - *p = curr->uv.next; - curr->uv.next = NULL; /* link `curr' at the end of `collected' list */ - *lastcollected = curr; - lastcollected = &curr->uv.next; - } - } - /* insert collected udata with gc event into `tmudata' list */ - *lastcollected = G(L)->tmudata; - G(L)->tmudata = collected; -} - - -static void removekey (Node *n) { - setnilvalue(val(n)); /* remove corresponding value ... */ - if (iscollectable(key(n))) - setttype(key(n), LUA_TNONE); /* dead key; remove it */ -} - - -static void traversetable (GCState *st, Table *h) { - int i; - int weakkey = 0; - int weakvalue = 0; - marktable(st, h->metatable); - lua_assert(h->lsizenode || h->node == G(st->L)->dummynode); - if (h->mode & (WEAKKEY | WEAKVALUE)) { /* weak table? */ - Table **weaklist; - weakkey = h->mode & WEAKKEY; - weakvalue = h->mode & WEAKVALUE; - weaklist = (weakkey && weakvalue) ? &st->wkv : - (weakkey) ? &st->wk : - &st->wv; - h->gclist = *weaklist; /* must be cleared after GC, ... */ - *weaklist = h; /* ... so put in the appropriate list */ - } - if (!weakvalue) { - i = sizearray(h); - while (i--) - markobject(st, &h->array[i]); - } - i = sizenode(h); - while (i--) { - Node *n = node(h, i); - if (!ttisnil(val(n))) { - lua_assert(!ttisnil(key(n))); - condmarkobject(st, key(n), !weakkey); - condmarkobject(st, val(n), !weakvalue); - } - } -} - - static void propagatemarks (GCState *st) { - while (st->tmark) { /* traverse marked tables */ - Table *h = st->tmark; /* get first table from list */ - st->tmark = h->gclist; /* remove it from list */ - traversetable(st, h); + while (st->tmark) { /* traverse marked objects */ + switch (st->tmark->gch.tt) { + case LUA_TTABLE: { + Table *h = gcotoh(st->tmark); + st->tmark = h->gclist; + traversetable(st, h); + break; + } + case LUA_TFUNCTION: { + Closure *cl = gcotocl(st->tmark); + st->tmark = cl->c.gclist; + traverseclosure(st, cl); + break; + } + case LUA_TTHREAD: { + lua_State *th = gcototh(st->tmark); + st->tmark = th->gclist; + traversestack(st, th); + break; + } + case LUA_TPROTO: { + Proto *p = gcotop(st->tmark); + st->tmark = p->gclist; + traverseproto(st, p); + break; + } + default: lua_assert(0); + } } } @@ -245,8 +276,9 @@ static int valismarked (const TObject *o) { /* ** clear collected keys from weaktables */ -static void cleartablekeys (Table *h) { - for (; h; h = h->gclist) { +static void cleartablekeys (GCObject *l) { + while (l) { + Table *h = gcotoh(l); int i = sizenode(h); lua_assert(h->mode & WEAKKEY); while (i--) { @@ -254,6 +286,7 @@ static void cleartablekeys (Table *h) { if (!valismarked(key(n))) /* key was collected? */ removekey(n); /* remove entry from table */ } + l = h->gclist; } } @@ -261,8 +294,9 @@ static void cleartablekeys (Table *h) { /* ** clear collected values from weaktables */ -static void cleartablevalues (Table *h) { - for (; h; h = h->gclist) { +static void cleartablevalues (GCObject *l) { + while (l) { + Table *h = gcotoh(l); int i = sizearray(h); lua_assert(h->mode & WEAKVALUE); while (i--) { @@ -276,27 +310,28 @@ static void cleartablevalues (Table *h) { if (!valismarked(val(n))) /* value was collected? */ removekey(n); /* remove entry from table */ } + l = h->gclist; } } static void freeobj (lua_State *L, GCObject *o) { switch (o->gch.tt) { - case LUA_TPROTO: luaF_freeproto(L, &o->p); break; - case LUA_TFUNCTION: luaF_freeclosure(L, &o->cl); break; - case LUA_TUPVAL: luaM_freelem(L, &o->uv); break; - case LUA_TTABLE: luaH_free(L, &o->h); break; + case LUA_TPROTO: luaF_freeproto(L, gcotop(o)); break; + case LUA_TFUNCTION: luaF_freeclosure(L, gcotocl(o)); break; + case LUA_TUPVAL: luaM_freelem(L, gcotouv(o)); break; + case LUA_TTABLE: luaH_free(L, gcotoh(o)); break; case LUA_TTHREAD: { - lua_assert(&o->th != L && &o->th != G(L)->mainthread); - luaE_freethread(L, &o->th); + lua_assert(gcototh(o) != L && gcototh(o) != G(L)->mainthread); + luaE_freethread(L, gcototh(o)); break; } case LUA_TSTRING: { - luaM_free(L, o, sizestring((&o->ts)->tsv.len)); + luaM_free(L, o, sizestring(gcotots(o)->tsv.len)); break; } case LUA_TUSERDATA: { - luaM_free(L, o, sizeudata((&o->u)->uv.len)); + luaM_free(L, o, sizeudata(gcotou(o)->uv.len)); break; } default: lua_assert(0); @@ -360,14 +395,15 @@ static void callGCTM (lua_State *L) { setallowhook(L, 0); /* stop debug hooks during GC tag methods */ L->top++; /* reserve space to keep udata while runs its gc method */ while (G(L)->tmudata != NULL) { - GCObject *udata = G(L)->tmudata; + GCObject *o = G(L)->tmudata; + Udata *udata = gcotou(o); G(L)->tmudata = udata->uv.next; /* remove udata from `tmudata' */ udata->uv.next = G(L)->rootudata; /* return it to `root' list */ - G(L)->rootudata = udata; - setuvalue(L->top - 1, &udata->u); /* keep a reference to it */ - unmark(udata); - markfinalized(&udata->u); - do1gcTM(L, &udata->u); + G(L)->rootudata = o; + setuvalue(L->top - 1, udata); /* keep a reference to it */ + unmark(o); + markfinalized(udata); + do1gcTM(L, udata); } L->top--; setallowhook(L, oldah); /* restore hooks */ @@ -389,23 +425,23 @@ void luaC_sweep (lua_State *L, int all) { /* mark root set */ -static void markroot (GCState *st) { - lua_State *L = st->L; +static void markroot (GCState *st, lua_State *L) { + global_State *G = st->G; markobject(st, defaultmeta(L)); markobject(st, registry(L)); - markstack(st, G(L)->mainthread); - if (L != G(L)->mainthread) /* another thread is running? */ - reallymarkobject(st, cast(GCObject *, L)); /* cannot collect it */ + traversestack(st, G->mainthread); + if (L != G->mainthread) /* another thread is running? */ + markvalue(st, L); /* cannot collect it */ } static void mark (lua_State *L) { GCState st; - Table *wkv; - st.L = L; + GCObject *wkv; + st.G = G(L); st.tmark = NULL; st.wkv = st.wk = st.wv = NULL; - markroot(&st); + markroot(&st, L); propagatemarks(&st); /* mark all reachable objects */ cleartablevalues(st.wkv); cleartablevalues(st.wv); diff --git a/lobject.h b/lobject.h index 1867ee99..d0352c10 100644 --- a/lobject.h +++ b/lobject.h @@ -1,5 +1,5 @@ /* -** $Id: lobject.h,v 1.151 2002/11/04 12:31:44 roberto Exp roberto $ +** $Id: lobject.h,v 1.152 2002/11/07 15:37:10 roberto Exp roberto $ ** Type definitions for Lua objects ** See Copyright Notice in lua.h */ @@ -219,6 +219,7 @@ typedef struct Proto { int sizep; /* size of `p' */ int sizelocvars; int lineDefined; + GCObject *gclist; lu_byte nupvalues; lu_byte numparams; lu_byte is_vararg; @@ -249,19 +250,18 @@ typedef struct UpVal { ** Closures */ +#define ClosureHeader \ + CommonHeader; lu_byte isC; lu_byte nupvalues; GCObject *gclist + typedef struct CClosure { - CommonHeader; - lu_byte isC; /* 0 for Lua functions, 1 for C functions */ - lu_byte nupvalues; + ClosureHeader; lua_CFunction f; TObject upvalue[1]; } CClosure; typedef struct LClosure { - CommonHeader; - lu_byte isC; - lu_byte nupvalues; /* first five fields must be equal to CClosure!! */ + ClosureHeader; struct Proto *p; TObject g; /* global table for this closure */ UpVal *upvals[1]; @@ -298,7 +298,7 @@ typedef struct Table { TObject *array; /* array part */ Node *node; Node *firstfree; /* this position is free; all positions after it are full */ - struct Table *gclist; + GCObject *gclist; int sizearray; /* size of `array' array */ } Table;