From d7ca8ea57b3a189fae5d7f69693ca656e6deedae Mon Sep 17 00:00:00 2001 From: Alexander Harkness Date: Sun, 24 Nov 2013 14:27:32 +0000 Subject: Moved Lua --- lua-5.1.4/src/lgc.c | 711 ---------------------------------------------------- 1 file changed, 711 deletions(-) delete mode 100644 lua-5.1.4/src/lgc.c (limited to 'lua-5.1.4/src/lgc.c') diff --git a/lua-5.1.4/src/lgc.c b/lua-5.1.4/src/lgc.c deleted file mode 100644 index d9e0b7829..000000000 --- a/lua-5.1.4/src/lgc.c +++ /dev/null @@ -1,711 +0,0 @@ -/* -** $Id: lgc.c,v 2.38.1.1 2007/12/27 13:02:25 roberto Exp $ -** Garbage Collector -** See Copyright Notice in lua.h -*/ - -#include - -#define lgc_c -#define LUA_CORE - -#include "lua.h" - -#include "ldebug.h" -#include "ldo.h" -#include "lfunc.h" -#include "lgc.h" -#include "lmem.h" -#include "lobject.h" -#include "lstate.h" -#include "lstring.h" -#include "ltable.h" -#include "ltm.h" - - -#define GCSTEPSIZE 1024u -#define GCSWEEPMAX 40 -#define GCSWEEPCOST 10 -#define GCFINALIZECOST 100 - - -#define maskmarks cast_byte(~(bitmask(BLACKBIT)|WHITEBITS)) - -#define makewhite(g,x) \ - ((x)->gch.marked = cast_byte(((x)->gch.marked & maskmarks) | luaC_white(g))) - -#define white2gray(x) reset2bits((x)->gch.marked, WHITE0BIT, WHITE1BIT) -#define black2gray(x) resetbit((x)->gch.marked, BLACKBIT) - -#define stringmark(s) reset2bits((s)->tsv.marked, WHITE0BIT, WHITE1BIT) - - -#define isfinalized(u) testbit((u)->marked, FINALIZEDBIT) -#define markfinalized(u) l_setbit((u)->marked, FINALIZEDBIT) - - -#define KEYWEAK bitmask(KEYWEAKBIT) -#define VALUEWEAK bitmask(VALUEWEAKBIT) - - - -#define markvalue(g,o) { checkconsistency(o); \ - if (iscollectable(o) && iswhite(gcvalue(o))) reallymarkobject(g,gcvalue(o)); } - -#define markobject(g,t) { if (iswhite(obj2gco(t))) \ - reallymarkobject(g, obj2gco(t)); } - - -#define setthreshold(g) (g->GCthreshold = (g->estimate/100) * g->gcpause) - - -static void removeentry (Node *n) { - lua_assert(ttisnil(gval(n))); - if (iscollectable(gkey(n))) - setttype(gkey(n), LUA_TDEADKEY); /* dead key; remove it */ -} - - -static void reallymarkobject (global_State *g, GCObject *o) { - lua_assert(iswhite(o) && !isdead(g, o)); - white2gray(o); - switch (o->gch.tt) { - case LUA_TSTRING: { - return; - } - case LUA_TUSERDATA: { - Table *mt = gco2u(o)->metatable; - gray2black(o); /* udata are never gray */ - if (mt) markobject(g, mt); - markobject(g, gco2u(o)->env); - return; - } - case LUA_TUPVAL: { - UpVal *uv = gco2uv(o); - markvalue(g, uv->v); - if (uv->v == &uv->u.value) /* closed? */ - gray2black(o); /* open upvalues are never black */ - return; - } - case LUA_TFUNCTION: { - gco2cl(o)->c.gclist = g->gray; - g->gray = o; - break; - } - case LUA_TTABLE: { - gco2h(o)->gclist = g->gray; - g->gray = o; - break; - } - case LUA_TTHREAD: { - gco2th(o)->gclist = g->gray; - g->gray = o; - break; - } - case LUA_TPROTO: { - gco2p(o)->gclist = g->gray; - g->gray = o; - break; - } - default: lua_assert(0); - } -} - - -static void marktmu (global_State *g) { - GCObject *u = g->tmudata; - if (u) { - do { - u = u->gch.next; - makewhite(g, u); /* may be marked, if left from previous GC */ - reallymarkobject(g, u); - } while (u != g->tmudata); - } -} - - -/* move `dead' udata that need finalization to list `tmudata' */ -size_t luaC_separateudata (lua_State *L, int all) { - global_State *g = G(L); - size_t deadmem = 0; - GCObject **p = &g->mainthread->next; - GCObject *curr; - while ((curr = *p) != NULL) { - if (!(iswhite(curr) || all) || isfinalized(gco2u(curr))) - p = &curr->gch.next; /* don't bother with them */ - else if (fasttm(L, gco2u(curr)->metatable, TM_GC) == NULL) { - markfinalized(gco2u(curr)); /* don't need finalization */ - p = &curr->gch.next; - } - else { /* must call its gc method */ - deadmem += sizeudata(gco2u(curr)); - markfinalized(gco2u(curr)); - *p = curr->gch.next; - /* link `curr' at the end of `tmudata' list */ - if (g->tmudata == NULL) /* list is empty? */ - g->tmudata = curr->gch.next = curr; /* creates a circular list */ - else { - curr->gch.next = g->tmudata->gch.next; - g->tmudata->gch.next = curr; - g->tmudata = curr; - } - } - } - return deadmem; -} - - -static int traversetable (global_State *g, Table *h) { - int i; - int weakkey = 0; - int weakvalue = 0; - const TValue *mode; - if (h->metatable) - markobject(g, h->metatable); - mode = gfasttm(g, h->metatable, TM_MODE); - if (mode && ttisstring(mode)) { /* is there a weak mode? */ - weakkey = (strchr(svalue(mode), 'k') != NULL); - weakvalue = (strchr(svalue(mode), 'v') != NULL); - if (weakkey || weakvalue) { /* is really weak? */ - h->marked &= ~(KEYWEAK | VALUEWEAK); /* clear bits */ - h->marked |= cast_byte((weakkey << KEYWEAKBIT) | - (weakvalue << VALUEWEAKBIT)); - h->gclist = g->weak; /* must be cleared after GC, ... */ - g->weak = obj2gco(h); /* ... so put in the appropriate list */ - } - } - if (weakkey && weakvalue) return 1; - if (!weakvalue) { - i = h->sizearray; - while (i--) - markvalue(g, &h->array[i]); - } - i = sizenode(h); - while (i--) { - Node *n = gnode(h, i); - lua_assert(ttype(gkey(n)) != LUA_TDEADKEY || ttisnil(gval(n))); - if (ttisnil(gval(n))) - removeentry(n); /* remove empty entries */ - else { - lua_assert(!ttisnil(gkey(n))); - if (!weakkey) markvalue(g, gkey(n)); - if (!weakvalue) markvalue(g, gval(n)); - } - } - return weakkey || weakvalue; -} - - -/* -** All marks are conditional because a GC may happen while the -** prototype is still being created -*/ -static void traverseproto (global_State *g, Proto *f) { - int i; - if (f->source) stringmark(f->source); - for (i=0; isizek; i++) /* mark literals */ - markvalue(g, &f->k[i]); - for (i=0; isizeupvalues; i++) { /* mark upvalue names */ - if (f->upvalues[i]) - stringmark(f->upvalues[i]); - } - for (i=0; isizep; i++) { /* mark nested protos */ - if (f->p[i]) - markobject(g, f->p[i]); - } - for (i=0; isizelocvars; i++) { /* mark local-variable names */ - if (f->locvars[i].varname) - stringmark(f->locvars[i].varname); - } -} - - - -static void traverseclosure (global_State *g, Closure *cl) { - markobject(g, cl->c.env); - if (cl->c.isC) { - int i; - for (i=0; ic.nupvalues; i++) /* mark its upvalues */ - markvalue(g, &cl->c.upvalue[i]); - } - else { - int i; - lua_assert(cl->l.nupvalues == cl->l.p->nups); - markobject(g, cl->l.p); - for (i=0; il.nupvalues; i++) /* mark its upvalues */ - markobject(g, cl->l.upvals[i]); - } -} - - -static void checkstacksizes (lua_State *L, StkId max) { - int ci_used = cast_int(L->ci - L->base_ci); /* number of `ci' in use */ - int s_used = cast_int(max - L->stack); /* part of stack in use */ - if (L->size_ci > LUAI_MAXCALLS) /* handling overflow? */ - return; /* do not touch the stacks */ - if (4*ci_used < L->size_ci && 2*BASIC_CI_SIZE < L->size_ci) - luaD_reallocCI(L, L->size_ci/2); /* still big enough... */ - condhardstacktests(luaD_reallocCI(L, ci_used + 1)); - if (4*s_used < L->stacksize && - 2*(BASIC_STACK_SIZE+EXTRA_STACK) < L->stacksize) - luaD_reallocstack(L, L->stacksize/2); /* still big enough... */ - condhardstacktests(luaD_reallocstack(L, s_used)); -} - - -static void traversestack (global_State *g, lua_State *l) { - StkId o, lim; - CallInfo *ci; - markvalue(g, gt(l)); - lim = l->top; - for (ci = l->base_ci; ci <= l->ci; ci++) { - lua_assert(ci->top <= l->stack_last); - if (lim < ci->top) lim = ci->top; - } - for (o = l->stack; o < l->top; o++) - markvalue(g, o); - for (; o <= lim; o++) - setnilvalue(o); - checkstacksizes(l, lim); -} - - -/* -** traverse one gray object, turning it to black. -** Returns `quantity' traversed. -*/ -static l_mem propagatemark (global_State *g) { - GCObject *o = g->gray; - lua_assert(isgray(o)); - gray2black(o); - switch (o->gch.tt) { - case LUA_TTABLE: { - Table *h = gco2h(o); - g->gray = h->gclist; - if (traversetable(g, h)) /* table is weak? */ - black2gray(o); /* keep it gray */ - return sizeof(Table) + sizeof(TValue) * h->sizearray + - sizeof(Node) * sizenode(h); - } - case LUA_TFUNCTION: { - Closure *cl = gco2cl(o); - g->gray = cl->c.gclist; - traverseclosure(g, cl); - return (cl->c.isC) ? sizeCclosure(cl->c.nupvalues) : - sizeLclosure(cl->l.nupvalues); - } - case LUA_TTHREAD: { - lua_State *th = gco2th(o); - g->gray = th->gclist; - th->gclist = g->grayagain; - g->grayagain = o; - black2gray(o); - traversestack(g, th); - return sizeof(lua_State) + sizeof(TValue) * th->stacksize + - sizeof(CallInfo) * th->size_ci; - } - case LUA_TPROTO: { - Proto *p = gco2p(o); - g->gray = p->gclist; - traverseproto(g, p); - return sizeof(Proto) + sizeof(Instruction) * p->sizecode + - sizeof(Proto *) * p->sizep + - sizeof(TValue) * p->sizek + - sizeof(int) * p->sizelineinfo + - sizeof(LocVar) * p->sizelocvars + - sizeof(TString *) * p->sizeupvalues; - } - default: lua_assert(0); return 0; - } -} - - -static size_t propagateall (global_State *g) { - size_t m = 0; - while (g->gray) m += propagatemark(g); - return m; -} - - -/* -** The next function tells whether a key or value can be cleared from -** a weak table. Non-collectable objects are never removed from weak -** tables. Strings behave as `values', so are never removed too. for -** other objects: if really collected, cannot keep them; for userdata -** being finalized, keep them in keys, but not in values -*/ -static int iscleared (const TValue *o, int iskey) { - if (!iscollectable(o)) return 0; - if (ttisstring(o)) { - stringmark(rawtsvalue(o)); /* strings are `values', so are never weak */ - return 0; - } - return iswhite(gcvalue(o)) || - (ttisuserdata(o) && (!iskey && isfinalized(uvalue(o)))); -} - - -/* -** clear collected entries from weaktables -*/ -static void cleartable (GCObject *l) { - while (l) { - Table *h = gco2h(l); - int i = h->sizearray; - lua_assert(testbit(h->marked, VALUEWEAKBIT) || - testbit(h->marked, KEYWEAKBIT)); - if (testbit(h->marked, VALUEWEAKBIT)) { - while (i--) { - TValue *o = &h->array[i]; - if (iscleared(o, 0)) /* value was collected? */ - setnilvalue(o); /* remove value */ - } - } - i = sizenode(h); - while (i--) { - Node *n = gnode(h, i); - if (!ttisnil(gval(n)) && /* non-empty entry? */ - (iscleared(key2tval(n), 1) || iscleared(gval(n), 0))) { - setnilvalue(gval(n)); /* remove value ... */ - removeentry(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, gco2p(o)); break; - case LUA_TFUNCTION: luaF_freeclosure(L, gco2cl(o)); break; - case LUA_TUPVAL: luaF_freeupval(L, gco2uv(o)); break; - case LUA_TTABLE: luaH_free(L, gco2h(o)); break; - case LUA_TTHREAD: { - lua_assert(gco2th(o) != L && gco2th(o) != G(L)->mainthread); - luaE_freethread(L, gco2th(o)); - break; - } - case LUA_TSTRING: { - G(L)->strt.nuse--; - luaM_freemem(L, o, sizestring(gco2ts(o))); - break; - } - case LUA_TUSERDATA: { - luaM_freemem(L, o, sizeudata(gco2u(o))); - break; - } - default: lua_assert(0); - } -} - - - -#define sweepwholelist(L,p) sweeplist(L,p,MAX_LUMEM) - - -static GCObject **sweeplist (lua_State *L, GCObject **p, lu_mem count) { - GCObject *curr; - global_State *g = G(L); - int deadmask = otherwhite(g); - while ((curr = *p) != NULL && count-- > 0) { - if (curr->gch.tt == LUA_TTHREAD) /* sweep open upvalues of each thread */ - sweepwholelist(L, &gco2th(curr)->openupval); - if ((curr->gch.marked ^ WHITEBITS) & deadmask) { /* not dead? */ - lua_assert(!isdead(g, curr) || testbit(curr->gch.marked, FIXEDBIT)); - makewhite(g, curr); /* make it white (for next cycle) */ - p = &curr->gch.next; - } - else { /* must erase `curr' */ - lua_assert(isdead(g, curr) || deadmask == bitmask(SFIXEDBIT)); - *p = curr->gch.next; - if (curr == g->rootgc) /* is the first element of the list? */ - g->rootgc = curr->gch.next; /* adjust first */ - freeobj(L, curr); - } - } - return p; -} - - -static void checkSizes (lua_State *L) { - global_State *g = G(L); - /* check size of string hash */ - if (g->strt.nuse < cast(lu_int32, g->strt.size/4) && - g->strt.size > MINSTRTABSIZE*2) - luaS_resize(L, g->strt.size/2); /* table is too big */ - /* check size of buffer */ - if (luaZ_sizebuffer(&g->buff) > LUA_MINBUFFER*2) { /* buffer too big? */ - size_t newsize = luaZ_sizebuffer(&g->buff) / 2; - luaZ_resizebuffer(L, &g->buff, newsize); - } -} - - -static void GCTM (lua_State *L) { - global_State *g = G(L); - GCObject *o = g->tmudata->gch.next; /* get first element */ - Udata *udata = rawgco2u(o); - const TValue *tm; - /* remove udata from `tmudata' */ - if (o == g->tmudata) /* last element? */ - g->tmudata = NULL; - else - g->tmudata->gch.next = udata->uv.next; - udata->uv.next = g->mainthread->next; /* return it to `root' list */ - g->mainthread->next = o; - makewhite(g, o); - tm = fasttm(L, udata->uv.metatable, TM_GC); - if (tm != NULL) { - lu_byte oldah = L->allowhook; - lu_mem oldt = g->GCthreshold; - L->allowhook = 0; /* stop debug hooks during GC tag method */ - g->GCthreshold = 2*g->totalbytes; /* avoid GC steps */ - setobj2s(L, L->top, tm); - setuvalue(L, L->top+1, udata); - L->top += 2; - luaD_call(L, L->top - 2, 0); - L->allowhook = oldah; /* restore hooks */ - g->GCthreshold = oldt; /* restore threshold */ - } -} - - -/* -** Call all GC tag methods -*/ -void luaC_callGCTM (lua_State *L) { - while (G(L)->tmudata) - GCTM(L); -} - - -void luaC_freeall (lua_State *L) { - global_State *g = G(L); - int i; - g->currentwhite = WHITEBITS | bitmask(SFIXEDBIT); /* mask to collect all elements */ - sweepwholelist(L, &g->rootgc); - for (i = 0; i < g->strt.size; i++) /* free all string lists */ - sweepwholelist(L, &g->strt.hash[i]); -} - - -static void markmt (global_State *g) { - int i; - for (i=0; imt[i]) markobject(g, g->mt[i]); -} - - -/* mark root set */ -static void markroot (lua_State *L) { - global_State *g = G(L); - g->gray = NULL; - g->grayagain = NULL; - g->weak = NULL; - markobject(g, g->mainthread); - /* make global table be traversed before main stack */ - markvalue(g, gt(g->mainthread)); - markvalue(g, registry(L)); - markmt(g); - g->gcstate = GCSpropagate; -} - - -static void remarkupvals (global_State *g) { - UpVal *uv; - for (uv = g->uvhead.u.l.next; uv != &g->uvhead; uv = uv->u.l.next) { - lua_assert(uv->u.l.next->u.l.prev == uv && uv->u.l.prev->u.l.next == uv); - if (isgray(obj2gco(uv))) - markvalue(g, uv->v); - } -} - - -static void atomic (lua_State *L) { - global_State *g = G(L); - size_t udsize; /* total size of userdata to be finalized */ - /* remark occasional upvalues of (maybe) dead threads */ - remarkupvals(g); - /* traverse objects cautch by write barrier and by 'remarkupvals' */ - propagateall(g); - /* remark weak tables */ - g->gray = g->weak; - g->weak = NULL; - lua_assert(!iswhite(obj2gco(g->mainthread))); - markobject(g, L); /* mark running thread */ - markmt(g); /* mark basic metatables (again) */ - propagateall(g); - /* remark gray again */ - g->gray = g->grayagain; - g->grayagain = NULL; - propagateall(g); - udsize = luaC_separateudata(L, 0); /* separate userdata to be finalized */ - marktmu(g); /* mark `preserved' userdata */ - udsize += propagateall(g); /* remark, to propagate `preserveness' */ - cleartable(g->weak); /* remove collected objects from weak tables */ - /* flip current white */ - g->currentwhite = cast_byte(otherwhite(g)); - g->sweepstrgc = 0; - g->sweepgc = &g->rootgc; - g->gcstate = GCSsweepstring; - g->estimate = g->totalbytes - udsize; /* first estimate */ -} - - -static l_mem singlestep (lua_State *L) { - global_State *g = G(L); - /*lua_checkmemory(L);*/ - switch (g->gcstate) { - case GCSpause: { - markroot(L); /* start a new collection */ - return 0; - } - case GCSpropagate: { - if (g->gray) - return propagatemark(g); - else { /* no more `gray' objects */ - atomic(L); /* finish mark phase */ - return 0; - } - } - case GCSsweepstring: { - lu_mem old = g->totalbytes; - sweepwholelist(L, &g->strt.hash[g->sweepstrgc++]); - if (g->sweepstrgc >= g->strt.size) /* nothing more to sweep? */ - g->gcstate = GCSsweep; /* end sweep-string phase */ - lua_assert(old >= g->totalbytes); - g->estimate -= old - g->totalbytes; - return GCSWEEPCOST; - } - case GCSsweep: { - lu_mem old = g->totalbytes; - g->sweepgc = sweeplist(L, g->sweepgc, GCSWEEPMAX); - if (*g->sweepgc == NULL) { /* nothing more to sweep? */ - checkSizes(L); - g->gcstate = GCSfinalize; /* end sweep phase */ - } - lua_assert(old >= g->totalbytes); - g->estimate -= old - g->totalbytes; - return GCSWEEPMAX*GCSWEEPCOST; - } - case GCSfinalize: { - if (g->tmudata) { - GCTM(L); - if (g->estimate > GCFINALIZECOST) - g->estimate -= GCFINALIZECOST; - return GCFINALIZECOST; - } - else { - g->gcstate = GCSpause; /* end collection */ - g->gcdept = 0; - return 0; - } - } - default: lua_assert(0); return 0; - } -} - - -void luaC_step (lua_State *L) { - global_State *g = G(L); - l_mem lim = (GCSTEPSIZE/100) * g->gcstepmul; - if (lim == 0) - lim = (MAX_LUMEM-1)/2; /* no limit */ - g->gcdept += g->totalbytes - g->GCthreshold; - do { - lim -= singlestep(L); - if (g->gcstate == GCSpause) - break; - } while (lim > 0); - if (g->gcstate != GCSpause) { - if (g->gcdept < GCSTEPSIZE) - g->GCthreshold = g->totalbytes + GCSTEPSIZE; /* - lim/g->gcstepmul;*/ - else { - g->gcdept -= GCSTEPSIZE; - g->GCthreshold = g->totalbytes; - } - } - else { - lua_assert(g->totalbytes >= g->estimate); - setthreshold(g); - } -} - - -void luaC_fullgc (lua_State *L) { - global_State *g = G(L); - if (g->gcstate <= GCSpropagate) { - /* reset sweep marks to sweep all elements (returning them to white) */ - g->sweepstrgc = 0; - g->sweepgc = &g->rootgc; - /* reset other collector lists */ - g->gray = NULL; - g->grayagain = NULL; - g->weak = NULL; - g->gcstate = GCSsweepstring; - } - lua_assert(g->gcstate != GCSpause && g->gcstate != GCSpropagate); - /* finish any pending sweep phase */ - while (g->gcstate != GCSfinalize) { - lua_assert(g->gcstate == GCSsweepstring || g->gcstate == GCSsweep); - singlestep(L); - } - markroot(L); - while (g->gcstate != GCSpause) { - singlestep(L); - } - setthreshold(g); -} - - -void luaC_barrierf (lua_State *L, GCObject *o, GCObject *v) { - global_State *g = G(L); - lua_assert(isblack(o) && iswhite(v) && !isdead(g, v) && !isdead(g, o)); - lua_assert(g->gcstate != GCSfinalize && g->gcstate != GCSpause); - lua_assert(ttype(&o->gch) != LUA_TTABLE); - /* must keep invariant? */ - if (g->gcstate == GCSpropagate) - reallymarkobject(g, v); /* restore invariant */ - else /* don't mind */ - makewhite(g, o); /* mark as white just to avoid other barriers */ -} - - -void luaC_barrierback (lua_State *L, Table *t) { - global_State *g = G(L); - GCObject *o = obj2gco(t); - lua_assert(isblack(o) && !isdead(g, o)); - lua_assert(g->gcstate != GCSfinalize && g->gcstate != GCSpause); - black2gray(o); /* make table gray (again) */ - t->gclist = g->grayagain; - g->grayagain = o; -} - - -void luaC_link (lua_State *L, GCObject *o, lu_byte tt) { - global_State *g = G(L); - o->gch.next = g->rootgc; - g->rootgc = o; - o->gch.marked = luaC_white(g); - o->gch.tt = tt; -} - - -void luaC_linkupval (lua_State *L, UpVal *uv) { - global_State *g = G(L); - GCObject *o = obj2gco(uv); - o->gch.next = g->rootgc; /* link upvalue into `rootgc' list */ - g->rootgc = o; - if (isgray(o)) { - if (g->gcstate == GCSpropagate) { - gray2black(o); /* closed upvalues need barrier */ - luaC_barrier(L, uv, uv->v); - } - else { /* sweep phase: sweep it (turning it into white) */ - makewhite(g, o); - lua_assert(g->gcstate != GCSfinalize && g->gcstate != GCSpause); - } - } -} - -- cgit v1.2.3