From ebc50b387ab209c9f9a0d92e340ac293d5697274 Mon Sep 17 00:00:00 2001 From: sanine Date: Sat, 11 Mar 2023 15:58:20 -0600 Subject: build & link with luajit instead of lua5.1 --- libs/luajit-cmake/luajit/src/lj_gc.c | 909 +++++++++++++++++++++++++++++++++++ 1 file changed, 909 insertions(+) create mode 100644 libs/luajit-cmake/luajit/src/lj_gc.c (limited to 'libs/luajit-cmake/luajit/src/lj_gc.c') diff --git a/libs/luajit-cmake/luajit/src/lj_gc.c b/libs/luajit-cmake/luajit/src/lj_gc.c new file mode 100644 index 0000000..2fc52ec --- /dev/null +++ b/libs/luajit-cmake/luajit/src/lj_gc.c @@ -0,0 +1,909 @@ +/* +** Garbage collector. +** Copyright (C) 2005-2022 Mike Pall. See Copyright Notice in luajit.h +** +** Major portions taken verbatim or adapted from the Lua interpreter. +** Copyright (C) 1994-2008 Lua.org, PUC-Rio. See Copyright Notice in lua.h +*/ + +#define lj_gc_c +#define LUA_CORE + +#include "lj_obj.h" +#include "lj_gc.h" +#include "lj_err.h" +#include "lj_buf.h" +#include "lj_str.h" +#include "lj_tab.h" +#include "lj_func.h" +#include "lj_udata.h" +#include "lj_meta.h" +#include "lj_state.h" +#include "lj_frame.h" +#if LJ_HASFFI +#include "lj_ctype.h" +#include "lj_cdata.h" +#endif +#include "lj_trace.h" +#include "lj_dispatch.h" +#include "lj_vm.h" + +#define GCSTEPSIZE 1024u +#define GCSWEEPMAX 40 +#define GCSWEEPCOST 10 +#define GCFINALIZECOST 100 + +/* Macros to set GCobj colors and flags. */ +#define white2gray(x) ((x)->gch.marked &= (uint8_t)~LJ_GC_WHITES) +#define gray2black(x) ((x)->gch.marked |= LJ_GC_BLACK) +#define isfinalized(u) ((u)->marked & LJ_GC_FINALIZED) + +/* -- Mark phase ---------------------------------------------------------- */ + +/* Mark a TValue (if needed). */ +#define gc_marktv(g, tv) \ + { lj_assertG(!tvisgcv(tv) || (~itype(tv) == gcval(tv)->gch.gct), \ + "TValue and GC type mismatch"); \ + if (tviswhite(tv)) gc_mark(g, gcV(tv)); } + +/* Mark a GCobj (if needed). */ +#define gc_markobj(g, o) \ + { if (iswhite(obj2gco(o))) gc_mark(g, obj2gco(o)); } + +/* Mark a string object. */ +#define gc_mark_str(s) ((s)->marked &= (uint8_t)~LJ_GC_WHITES) + +/* Mark a white GCobj. */ +static void gc_mark(global_State *g, GCobj *o) +{ + int gct = o->gch.gct; + lj_assertG(iswhite(o), "mark of non-white object"); + lj_assertG(!isdead(g, o), "mark of dead object"); + white2gray(o); + if (LJ_UNLIKELY(gct == ~LJ_TUDATA)) { + GCtab *mt = tabref(gco2ud(o)->metatable); + gray2black(o); /* Userdata are never gray. */ + if (mt) gc_markobj(g, mt); + gc_markobj(g, tabref(gco2ud(o)->env)); + if (LJ_HASBUFFER && gco2ud(o)->udtype == UDTYPE_BUFFER) { + SBufExt *sbx = (SBufExt *)uddata(gco2ud(o)); + if (sbufiscow(sbx) && gcref(sbx->cowref)) + gc_markobj(g, gcref(sbx->cowref)); + if (gcref(sbx->dict_str)) + gc_markobj(g, gcref(sbx->dict_str)); + if (gcref(sbx->dict_mt)) + gc_markobj(g, gcref(sbx->dict_mt)); + } + } else if (LJ_UNLIKELY(gct == ~LJ_TUPVAL)) { + GCupval *uv = gco2uv(o); + gc_marktv(g, uvval(uv)); + if (uv->closed) + gray2black(o); /* Closed upvalues are never gray. */ + } else if (gct != ~LJ_TSTR && gct != ~LJ_TCDATA) { + lj_assertG(gct == ~LJ_TFUNC || gct == ~LJ_TTAB || + gct == ~LJ_TTHREAD || gct == ~LJ_TPROTO || gct == ~LJ_TTRACE, + "bad GC type %d", gct); + setgcrefr(o->gch.gclist, g->gc.gray); + setgcref(g->gc.gray, o); + } +} + +/* Mark GC roots. */ +static void gc_mark_gcroot(global_State *g) +{ + ptrdiff_t i; + for (i = 0; i < GCROOT_MAX; i++) + if (gcref(g->gcroot[i]) != NULL) + gc_markobj(g, gcref(g->gcroot[i])); +} + +/* Start a GC cycle and mark the root set. */ +static void gc_mark_start(global_State *g) +{ + setgcrefnull(g->gc.gray); + setgcrefnull(g->gc.grayagain); + setgcrefnull(g->gc.weak); + gc_markobj(g, mainthread(g)); + gc_markobj(g, tabref(mainthread(g)->env)); + gc_marktv(g, &g->registrytv); + gc_mark_gcroot(g); + g->gc.state = GCSpropagate; +} + +/* Mark open upvalues. */ +static void gc_mark_uv(global_State *g) +{ + GCupval *uv; + for (uv = uvnext(&g->uvhead); uv != &g->uvhead; uv = uvnext(uv)) { + lj_assertG(uvprev(uvnext(uv)) == uv && uvnext(uvprev(uv)) == uv, + "broken upvalue chain"); + if (isgray(obj2gco(uv))) + gc_marktv(g, uvval(uv)); + } +} + +/* Mark userdata in mmudata list. */ +static void gc_mark_mmudata(global_State *g) +{ + GCobj *root = gcref(g->gc.mmudata); + GCobj *u = root; + if (u) { + do { + u = gcnext(u); + makewhite(g, u); /* Could be from previous GC. */ + gc_mark(g, u); + } while (u != root); + } +} + +/* Separate userdata objects to be finalized to mmudata list. */ +size_t lj_gc_separateudata(global_State *g, int all) +{ + size_t m = 0; + GCRef *p = &mainthread(g)->nextgc; + GCobj *o; + while ((o = gcref(*p)) != NULL) { + if (!(iswhite(o) || all) || isfinalized(gco2ud(o))) { + p = &o->gch.nextgc; /* Nothing to do. */ + } else if (!lj_meta_fastg(g, tabref(gco2ud(o)->metatable), MM_gc)) { + markfinalized(o); /* Done, as there's no __gc metamethod. */ + p = &o->gch.nextgc; + } else { /* Otherwise move userdata to be finalized to mmudata list. */ + m += sizeudata(gco2ud(o)); + markfinalized(o); + *p = o->gch.nextgc; + if (gcref(g->gc.mmudata)) { /* Link to end of mmudata list. */ + GCobj *root = gcref(g->gc.mmudata); + setgcrefr(o->gch.nextgc, root->gch.nextgc); + setgcref(root->gch.nextgc, o); + setgcref(g->gc.mmudata, o); + } else { /* Create circular list. */ + setgcref(o->gch.nextgc, o); + setgcref(g->gc.mmudata, o); + } + } + } + return m; +} + +/* -- Propagation phase --------------------------------------------------- */ + +/* Traverse a table. */ +static int gc_traverse_tab(global_State *g, GCtab *t) +{ + int weak = 0; + cTValue *mode; + GCtab *mt = tabref(t->metatable); + if (mt) + gc_markobj(g, mt); + mode = lj_meta_fastg(g, mt, MM_mode); + if (mode && tvisstr(mode)) { /* Valid __mode field? */ + const char *modestr = strVdata(mode); + int c; + while ((c = *modestr++)) { + if (c == 'k') weak |= LJ_GC_WEAKKEY; + else if (c == 'v') weak |= LJ_GC_WEAKVAL; + } + if (weak) { /* Weak tables are cleared in the atomic phase. */ +#if LJ_HASFFI + CTState *cts = ctype_ctsG(g); + if (cts && cts->finalizer == t) { + weak = (int)(~0u & ~LJ_GC_WEAKVAL); + } else +#endif + { + t->marked = (uint8_t)((t->marked & ~LJ_GC_WEAK) | weak); + setgcrefr(t->gclist, g->gc.weak); + setgcref(g->gc.weak, obj2gco(t)); + } + } + } + if (weak == LJ_GC_WEAK) /* Nothing to mark if both keys/values are weak. */ + return 1; + if (!(weak & LJ_GC_WEAKVAL)) { /* Mark array part. */ + MSize i, asize = t->asize; + for (i = 0; i < asize; i++) + gc_marktv(g, arrayslot(t, i)); + } + if (t->hmask > 0) { /* Mark hash part. */ + Node *node = noderef(t->node); + MSize i, hmask = t->hmask; + for (i = 0; i <= hmask; i++) { + Node *n = &node[i]; + if (!tvisnil(&n->val)) { /* Mark non-empty slot. */ + lj_assertG(!tvisnil(&n->key), "mark of nil key in non-empty slot"); + if (!(weak & LJ_GC_WEAKKEY)) gc_marktv(g, &n->key); + if (!(weak & LJ_GC_WEAKVAL)) gc_marktv(g, &n->val); + } + } + } + return weak; +} + +/* Traverse a function. */ +static void gc_traverse_func(global_State *g, GCfunc *fn) +{ + gc_markobj(g, tabref(fn->c.env)); + if (isluafunc(fn)) { + uint32_t i; + lj_assertG(fn->l.nupvalues <= funcproto(fn)->sizeuv, + "function upvalues out of range"); + gc_markobj(g, funcproto(fn)); + for (i = 0; i < fn->l.nupvalues; i++) /* Mark Lua function upvalues. */ + gc_markobj(g, &gcref(fn->l.uvptr[i])->uv); + } else { + uint32_t i; + for (i = 0; i < fn->c.nupvalues; i++) /* Mark C function upvalues. */ + gc_marktv(g, &fn->c.upvalue[i]); + } +} + +#if LJ_HASJIT +/* Mark a trace. */ +static void gc_marktrace(global_State *g, TraceNo traceno) +{ + GCobj *o = obj2gco(traceref(G2J(g), traceno)); + lj_assertG(traceno != G2J(g)->cur.traceno, "active trace escaped"); + if (iswhite(o)) { + white2gray(o); + setgcrefr(o->gch.gclist, g->gc.gray); + setgcref(g->gc.gray, o); + } +} + +/* Traverse a trace. */ +static void gc_traverse_trace(global_State *g, GCtrace *T) +{ + IRRef ref; + if (T->traceno == 0) return; + for (ref = T->nk; ref < REF_TRUE; ref++) { + IRIns *ir = &T->ir[ref]; + if (ir->o == IR_KGC) + gc_markobj(g, ir_kgc(ir)); + if (irt_is64(ir->t) && ir->o != IR_KNULL) + ref++; + } + if (T->link) gc_marktrace(g, T->link); + if (T->nextroot) gc_marktrace(g, T->nextroot); + if (T->nextside) gc_marktrace(g, T->nextside); + gc_markobj(g, gcref(T->startpt)); +} + +/* The current trace is a GC root while not anchored in the prototype (yet). */ +#define gc_traverse_curtrace(g) gc_traverse_trace(g, &G2J(g)->cur) +#else +#define gc_traverse_curtrace(g) UNUSED(g) +#endif + +/* Traverse a prototype. */ +static void gc_traverse_proto(global_State *g, GCproto *pt) +{ + ptrdiff_t i; + gc_mark_str(proto_chunkname(pt)); + for (i = -(ptrdiff_t)pt->sizekgc; i < 0; i++) /* Mark collectable consts. */ + gc_markobj(g, proto_kgc(pt, i)); +#if LJ_HASJIT + if (pt->trace) gc_marktrace(g, pt->trace); +#endif +} + +/* Traverse the frame structure of a stack. */ +static MSize gc_traverse_frames(global_State *g, lua_State *th) +{ + TValue *frame, *top = th->top-1, *bot = tvref(th->stack); + /* Note: extra vararg frame not skipped, marks function twice (harmless). */ + for (frame = th->base-1; frame > bot+LJ_FR2; frame = frame_prev(frame)) { + GCfunc *fn = frame_func(frame); + TValue *ftop = frame; + if (isluafunc(fn)) ftop += funcproto(fn)->framesize; + if (ftop > top) top = ftop; + if (!LJ_FR2) gc_markobj(g, fn); /* Need to mark hidden function (or L). */ + } + top++; /* Correct bias of -1 (frame == base-1). */ + if (top > tvref(th->maxstack)) top = tvref(th->maxstack); + return (MSize)(top - bot); /* Return minimum needed stack size. */ +} + +/* Traverse a thread object. */ +static void gc_traverse_thread(global_State *g, lua_State *th) +{ + TValue *o, *top = th->top; + for (o = tvref(th->stack)+1+LJ_FR2; o < top; o++) + gc_marktv(g, o); + if (g->gc.state == GCSatomic) { + top = tvref(th->stack) + th->stacksize; + for (; o < top; o++) /* Clear unmarked slots. */ + setnilV(o); + } + gc_markobj(g, tabref(th->env)); + lj_state_shrinkstack(th, gc_traverse_frames(g, th)); +} + +/* Propagate one gray object. Traverse it and turn it black. */ +static size_t propagatemark(global_State *g) +{ + GCobj *o = gcref(g->gc.gray); + int gct = o->gch.gct; + lj_assertG(isgray(o), "propagation of non-gray object"); + gray2black(o); + setgcrefr(g->gc.gray, o->gch.gclist); /* Remove from gray list. */ + if (LJ_LIKELY(gct == ~LJ_TTAB)) { + GCtab *t = gco2tab(o); + if (gc_traverse_tab(g, t) > 0) + black2gray(o); /* Keep weak tables gray. */ + return sizeof(GCtab) + sizeof(TValue) * t->asize + + (t->hmask ? sizeof(Node) * (t->hmask + 1) : 0); + } else if (LJ_LIKELY(gct == ~LJ_TFUNC)) { + GCfunc *fn = gco2func(o); + gc_traverse_func(g, fn); + return isluafunc(fn) ? sizeLfunc((MSize)fn->l.nupvalues) : + sizeCfunc((MSize)fn->c.nupvalues); + } else if (LJ_LIKELY(gct == ~LJ_TPROTO)) { + GCproto *pt = gco2pt(o); + gc_traverse_proto(g, pt); + return pt->sizept; + } else if (LJ_LIKELY(gct == ~LJ_TTHREAD)) { + lua_State *th = gco2th(o); + setgcrefr(th->gclist, g->gc.grayagain); + setgcref(g->gc.grayagain, o); + black2gray(o); /* Threads are never black. */ + gc_traverse_thread(g, th); + return sizeof(lua_State) + sizeof(TValue) * th->stacksize; + } else { +#if LJ_HASJIT + GCtrace *T = gco2trace(o); + gc_traverse_trace(g, T); + return ((sizeof(GCtrace)+7)&~7) + (T->nins-T->nk)*sizeof(IRIns) + + T->nsnap*sizeof(SnapShot) + T->nsnapmap*sizeof(SnapEntry); +#else + lj_assertG(0, "bad GC type %d", gct); + return 0; +#endif + } +} + +/* Propagate all gray objects. */ +static size_t gc_propagate_gray(global_State *g) +{ + size_t m = 0; + while (gcref(g->gc.gray) != NULL) + m += propagatemark(g); + return m; +} + +/* -- Sweep phase --------------------------------------------------------- */ + +/* Type of GC free functions. */ +typedef void (LJ_FASTCALL *GCFreeFunc)(global_State *g, GCobj *o); + +/* GC free functions for LJ_TSTR .. LJ_TUDATA. ORDER LJ_T */ +static const GCFreeFunc gc_freefunc[] = { + (GCFreeFunc)lj_str_free, + (GCFreeFunc)lj_func_freeuv, + (GCFreeFunc)lj_state_free, + (GCFreeFunc)lj_func_freeproto, + (GCFreeFunc)lj_func_free, +#if LJ_HASJIT + (GCFreeFunc)lj_trace_free, +#else + (GCFreeFunc)0, +#endif +#if LJ_HASFFI + (GCFreeFunc)lj_cdata_free, +#else + (GCFreeFunc)0, +#endif + (GCFreeFunc)lj_tab_free, + (GCFreeFunc)lj_udata_free +}; + +/* Full sweep of a GC list. */ +#define gc_fullsweep(g, p) gc_sweep(g, (p), ~(uint32_t)0) + +/* Partial sweep of a GC list. */ +static GCRef *gc_sweep(global_State *g, GCRef *p, uint32_t lim) +{ + /* Mask with other white and LJ_GC_FIXED. Or LJ_GC_SFIXED on shutdown. */ + int ow = otherwhite(g); + GCobj *o; + while ((o = gcref(*p)) != NULL && lim-- > 0) { + if (o->gch.gct == ~LJ_TTHREAD) /* Need to sweep open upvalues, too. */ + gc_fullsweep(g, &gco2th(o)->openupval); + if (((o->gch.marked ^ LJ_GC_WHITES) & ow)) { /* Black or current white? */ + lj_assertG(!isdead(g, o) || (o->gch.marked & LJ_GC_FIXED), + "sweep of undead object"); + makewhite(g, o); /* Value is alive, change to the current white. */ + p = &o->gch.nextgc; + } else { /* Otherwise value is dead, free it. */ + lj_assertG(isdead(g, o) || ow == LJ_GC_SFIXED, + "sweep of unlive object"); + setgcrefr(*p, o->gch.nextgc); + if (o == gcref(g->gc.root)) + setgcrefr(g->gc.root, o->gch.nextgc); /* Adjust list anchor. */ + gc_freefunc[o->gch.gct - ~LJ_TSTR](g, o); + } + } + return p; +} + +/* Sweep one string interning table chain. Preserves hashalg bit. */ +static void gc_sweepstr(global_State *g, GCRef *chain) +{ + /* Mask with other white and LJ_GC_FIXED. Or LJ_GC_SFIXED on shutdown. */ + int ow = otherwhite(g); + uintptr_t u = gcrefu(*chain); + GCRef q; + GCRef *p = &q; + GCobj *o; + setgcrefp(q, (u & ~(uintptr_t)1)); + while ((o = gcref(*p)) != NULL) { + if (((o->gch.marked ^ LJ_GC_WHITES) & ow)) { /* Black or current white? */ + lj_assertG(!isdead(g, o) || (o->gch.marked & LJ_GC_FIXED), + "sweep of undead string"); + makewhite(g, o); /* String is alive, change to the current white. */ + p = &o->gch.nextgc; + } else { /* Otherwise string is dead, free it. */ + lj_assertG(isdead(g, o) || ow == LJ_GC_SFIXED, + "sweep of unlive string"); + setgcrefr(*p, o->gch.nextgc); + lj_str_free(g, gco2str(o)); + } + } + setgcrefp(*chain, (gcrefu(q) | (u & 1))); +} + +/* Check whether we can clear a key or a value slot from a table. */ +static int gc_mayclear(cTValue *o, int val) +{ + if (tvisgcv(o)) { /* Only collectable objects can be weak references. */ + if (tvisstr(o)) { /* But strings cannot be used as weak references. */ + gc_mark_str(strV(o)); /* And need to be marked. */ + return 0; + } + if (iswhite(gcV(o))) + return 1; /* Object is about to be collected. */ + if (tvisudata(o) && val && isfinalized(udataV(o))) + return 1; /* Finalized userdata is dropped only from values. */ + } + return 0; /* Cannot clear. */ +} + +/* Clear collected entries from weak tables. */ +static void gc_clearweak(global_State *g, GCobj *o) +{ + UNUSED(g); + while (o) { + GCtab *t = gco2tab(o); + lj_assertG((t->marked & LJ_GC_WEAK), "clear of non-weak table"); + if ((t->marked & LJ_GC_WEAKVAL)) { + MSize i, asize = t->asize; + for (i = 0; i < asize; i++) { + /* Clear array slot when value is about to be collected. */ + TValue *tv = arrayslot(t, i); + if (gc_mayclear(tv, 1)) + setnilV(tv); + } + } + if (t->hmask > 0) { + Node *node = noderef(t->node); + MSize i, hmask = t->hmask; + for (i = 0; i <= hmask; i++) { + Node *n = &node[i]; + /* Clear hash slot when key or value is about to be collected. */ + if (!tvisnil(&n->val) && (gc_mayclear(&n->key, 0) || + gc_mayclear(&n->val, 1))) + setnilV(&n->val); + } + } + o = gcref(t->gclist); + } +} + +/* Call a userdata or cdata finalizer. */ +static void gc_call_finalizer(global_State *g, lua_State *L, + cTValue *mo, GCobj *o) +{ + /* Save and restore lots of state around the __gc callback. */ + uint8_t oldh = hook_save(g); + GCSize oldt = g->gc.threshold; + int errcode; + TValue *top; + lj_trace_abort(g); + hook_entergc(g); /* Disable hooks and new traces during __gc. */ + if (LJ_HASPROFILE && (oldh & HOOK_PROFILE)) lj_dispatch_update(g); + g->gc.threshold = LJ_MAX_MEM; /* Prevent GC steps. */ + top = L->top; + copyTV(L, top++, mo); + if (LJ_FR2) setnilV(top++); + setgcV(L, top, o, ~o->gch.gct); + L->top = top+1; + errcode = lj_vm_pcall(L, top, 1+0, -1); /* Stack: |mo|o| -> | */ + hook_restore(g, oldh); + if (LJ_HASPROFILE && (oldh & HOOK_PROFILE)) lj_dispatch_update(g); + g->gc.threshold = oldt; /* Restore GC threshold. */ + if (errcode) + lj_err_throw(L, errcode); /* Propagate errors. */ +} + +/* Finalize one userdata or cdata object from the mmudata list. */ +static void gc_finalize(lua_State *L) +{ + global_State *g = G(L); + GCobj *o = gcnext(gcref(g->gc.mmudata)); + cTValue *mo; + lj_assertG(tvref(g->jit_base) == NULL, "finalizer called on trace"); + /* Unchain from list of userdata to be finalized. */ + if (o == gcref(g->gc.mmudata)) + setgcrefnull(g->gc.mmudata); + else + setgcrefr(gcref(g->gc.mmudata)->gch.nextgc, o->gch.nextgc); +#if LJ_HASFFI + if (o->gch.gct == ~LJ_TCDATA) { + TValue tmp, *tv; + /* Add cdata back to the GC list and make it white. */ + setgcrefr(o->gch.nextgc, g->gc.root); + setgcref(g->gc.root, o); + makewhite(g, o); + o->gch.marked &= (uint8_t)~LJ_GC_CDATA_FIN; + /* Resolve finalizer. */ + setcdataV(L, &tmp, gco2cd(o)); + tv = lj_tab_set(L, ctype_ctsG(g)->finalizer, &tmp); + if (!tvisnil(tv)) { + g->gc.nocdatafin = 0; + copyTV(L, &tmp, tv); + setnilV(tv); /* Clear entry in finalizer table. */ + gc_call_finalizer(g, L, &tmp, o); + } + return; + } +#endif + /* Add userdata back to the main userdata list and make it white. */ + setgcrefr(o->gch.nextgc, mainthread(g)->nextgc); + setgcref(mainthread(g)->nextgc, o); + makewhite(g, o); + /* Resolve the __gc metamethod. */ + mo = lj_meta_fastg(g, tabref(gco2ud(o)->metatable), MM_gc); + if (mo) + gc_call_finalizer(g, L, mo, o); +} + +/* Finalize all userdata objects from mmudata list. */ +void lj_gc_finalize_udata(lua_State *L) +{ + while (gcref(G(L)->gc.mmudata) != NULL) + gc_finalize(L); +} + +#if LJ_HASFFI +/* Finalize all cdata objects from finalizer table. */ +void lj_gc_finalize_cdata(lua_State *L) +{ + global_State *g = G(L); + CTState *cts = ctype_ctsG(g); + if (cts) { + GCtab *t = cts->finalizer; + Node *node = noderef(t->node); + ptrdiff_t i; + setgcrefnull(t->metatable); /* Mark finalizer table as disabled. */ + for (i = (ptrdiff_t)t->hmask; i >= 0; i--) + if (!tvisnil(&node[i].val) && tviscdata(&node[i].key)) { + GCobj *o = gcV(&node[i].key); + TValue tmp; + makewhite(g, o); + o->gch.marked &= (uint8_t)~LJ_GC_CDATA_FIN; + copyTV(L, &tmp, &node[i].val); + setnilV(&node[i].val); + gc_call_finalizer(g, L, &tmp, o); + } + } +} +#endif + +/* Free all remaining GC objects. */ +void lj_gc_freeall(global_State *g) +{ + MSize i, strmask; + /* Free everything, except super-fixed objects (the main thread). */ + g->gc.currentwhite = LJ_GC_WHITES | LJ_GC_SFIXED; + gc_fullsweep(g, &g->gc.root); + strmask = g->str.mask; + for (i = 0; i <= strmask; i++) /* Free all string hash chains. */ + gc_sweepstr(g, &g->str.tab[i]); +} + +/* -- Collector ----------------------------------------------------------- */ + +/* Atomic part of the GC cycle, transitioning from mark to sweep phase. */ +static void atomic(global_State *g, lua_State *L) +{ + size_t udsize; + + gc_mark_uv(g); /* Need to remark open upvalues (the thread may be dead). */ + gc_propagate_gray(g); /* Propagate any left-overs. */ + + setgcrefr(g->gc.gray, g->gc.weak); /* Empty the list of weak tables. */ + setgcrefnull(g->gc.weak); + lj_assertG(!iswhite(obj2gco(mainthread(g))), "main thread turned white"); + gc_markobj(g, L); /* Mark running thread. */ + gc_traverse_curtrace(g); /* Traverse current trace. */ + gc_mark_gcroot(g); /* Mark GC roots (again). */ + gc_propagate_gray(g); /* Propagate all of the above. */ + + setgcrefr(g->gc.gray, g->gc.grayagain); /* Empty the 2nd chance list. */ + setgcrefnull(g->gc.grayagain); + gc_propagate_gray(g); /* Propagate it. */ + + udsize = lj_gc_separateudata(g, 0); /* Separate userdata to be finalized. */ + gc_mark_mmudata(g); /* Mark them. */ + udsize += gc_propagate_gray(g); /* And propagate the marks. */ + + /* All marking done, clear weak tables. */ + gc_clearweak(g, gcref(g->gc.weak)); + + lj_buf_shrink(L, &g->tmpbuf); /* Shrink temp buffer. */ + + /* Prepare for sweep phase. */ + g->gc.currentwhite = (uint8_t)otherwhite(g); /* Flip current white. */ + g->strempty.marked = g->gc.currentwhite; + setmref(g->gc.sweep, &g->gc.root); + g->gc.estimate = g->gc.total - (GCSize)udsize; /* Initial estimate. */ +} + +/* GC state machine. Returns a cost estimate for each step performed. */ +static size_t gc_onestep(lua_State *L) +{ + global_State *g = G(L); + switch (g->gc.state) { + case GCSpause: + gc_mark_start(g); /* Start a new GC cycle by marking all GC roots. */ + return 0; + case GCSpropagate: + if (gcref(g->gc.gray) != NULL) + return propagatemark(g); /* Propagate one gray object. */ + g->gc.state = GCSatomic; /* End of mark phase. */ + return 0; + case GCSatomic: + if (tvref(g->jit_base)) /* Don't run atomic phase on trace. */ + return LJ_MAX_MEM; + atomic(g, L); + g->gc.state = GCSsweepstring; /* Start of sweep phase. */ + g->gc.sweepstr = 0; + return 0; + case GCSsweepstring: { + GCSize old = g->gc.total; + gc_sweepstr(g, &g->str.tab[g->gc.sweepstr++]); /* Sweep one chain. */ + if (g->gc.sweepstr > g->str.mask) + g->gc.state = GCSsweep; /* All string hash chains sweeped. */ + lj_assertG(old >= g->gc.total, "sweep increased memory"); + g->gc.estimate -= old - g->gc.total; + return GCSWEEPCOST; + } + case GCSsweep: { + GCSize old = g->gc.total; + setmref(g->gc.sweep, gc_sweep(g, mref(g->gc.sweep, GCRef), GCSWEEPMAX)); + lj_assertG(old >= g->gc.total, "sweep increased memory"); + g->gc.estimate -= old - g->gc.total; + if (gcref(*mref(g->gc.sweep, GCRef)) == NULL) { + if (g->str.num <= (g->str.mask >> 2) && g->str.mask > LJ_MIN_STRTAB*2-1) + lj_str_resize(L, g->str.mask >> 1); /* Shrink string table. */ + if (gcref(g->gc.mmudata)) { /* Need any finalizations? */ + g->gc.state = GCSfinalize; +#if LJ_HASFFI + g->gc.nocdatafin = 1; +#endif + } else { /* Otherwise skip this phase to help the JIT. */ + g->gc.state = GCSpause; /* End of GC cycle. */ + g->gc.debt = 0; + } + } + return GCSWEEPMAX*GCSWEEPCOST; + } + case GCSfinalize: + if (gcref(g->gc.mmudata) != NULL) { + GCSize old = g->gc.total; + if (tvref(g->jit_base)) /* Don't call finalizers on trace. */ + return LJ_MAX_MEM; + gc_finalize(L); /* Finalize one userdata object. */ + if (old >= g->gc.total && g->gc.estimate > old - g->gc.total) + g->gc.estimate -= old - g->gc.total; + if (g->gc.estimate > GCFINALIZECOST) + g->gc.estimate -= GCFINALIZECOST; + return GCFINALIZECOST; + } +#if LJ_HASFFI + if (!g->gc.nocdatafin) lj_tab_rehash(L, ctype_ctsG(g)->finalizer); +#endif + g->gc.state = GCSpause; /* End of GC cycle. */ + g->gc.debt = 0; + return 0; + default: + lj_assertG(0, "bad GC state"); + return 0; + } +} + +/* Perform a limited amount of incremental GC steps. */ +int LJ_FASTCALL lj_gc_step(lua_State *L) +{ + global_State *g = G(L); + GCSize lim; + int32_t ostate = g->vmstate; + setvmstate(g, GC); + lim = (GCSTEPSIZE/100) * g->gc.stepmul; + if (lim == 0) + lim = LJ_MAX_MEM; + if (g->gc.total > g->gc.threshold) + g->gc.debt += g->gc.total - g->gc.threshold; + do { + lim -= (GCSize)gc_onestep(L); + if (g->gc.state == GCSpause) { + g->gc.threshold = (g->gc.estimate/100) * g->gc.pause; + g->vmstate = ostate; + return 1; /* Finished a GC cycle. */ + } + } while (sizeof(lim) == 8 ? ((int64_t)lim > 0) : ((int32_t)lim > 0)); + if (g->gc.debt < GCSTEPSIZE) { + g->gc.threshold = g->gc.total + GCSTEPSIZE; + g->vmstate = ostate; + return -1; + } else { + g->gc.debt -= GCSTEPSIZE; + g->gc.threshold = g->gc.total; + g->vmstate = ostate; + return 0; + } +} + +/* Ditto, but fix the stack top first. */ +void LJ_FASTCALL lj_gc_step_fixtop(lua_State *L) +{ + if (curr_funcisL(L)) L->top = curr_topL(L); + lj_gc_step(L); +} + +#if LJ_HASJIT +/* Perform multiple GC steps. Called from JIT-compiled code. */ +int LJ_FASTCALL lj_gc_step_jit(global_State *g, MSize steps) +{ + lua_State *L = gco2th(gcref(g->cur_L)); + L->base = tvref(G(L)->jit_base); + L->top = curr_topL(L); + while (steps-- > 0 && lj_gc_step(L) == 0) + ; + /* Return 1 to force a trace exit. */ + return (G(L)->gc.state == GCSatomic || G(L)->gc.state == GCSfinalize); +} +#endif + +/* Perform a full GC cycle. */ +void lj_gc_fullgc(lua_State *L) +{ + global_State *g = G(L); + int32_t ostate = g->vmstate; + setvmstate(g, GC); + if (g->gc.state <= GCSatomic) { /* Caught somewhere in the middle. */ + setmref(g->gc.sweep, &g->gc.root); /* Sweep everything (preserving it). */ + setgcrefnull(g->gc.gray); /* Reset lists from partial propagation. */ + setgcrefnull(g->gc.grayagain); + setgcrefnull(g->gc.weak); + g->gc.state = GCSsweepstring; /* Fast forward to the sweep phase. */ + g->gc.sweepstr = 0; + } + while (g->gc.state == GCSsweepstring || g->gc.state == GCSsweep) + gc_onestep(L); /* Finish sweep. */ + lj_assertG(g->gc.state == GCSfinalize || g->gc.state == GCSpause, + "bad GC state"); + /* Now perform a full GC. */ + g->gc.state = GCSpause; + do { gc_onestep(L); } while (g->gc.state != GCSpause); + g->gc.threshold = (g->gc.estimate/100) * g->gc.pause; + g->vmstate = ostate; +} + +/* -- Write barriers ------------------------------------------------------ */ + +/* Move the GC propagation frontier forward. */ +void lj_gc_barrierf(global_State *g, GCobj *o, GCobj *v) +{ + lj_assertG(isblack(o) && iswhite(v) && !isdead(g, v) && !isdead(g, o), + "bad object states for forward barrier"); + lj_assertG(g->gc.state != GCSfinalize && g->gc.state != GCSpause, + "bad GC state"); + lj_assertG(o->gch.gct != ~LJ_TTAB, "barrier object is not a table"); + /* Preserve invariant during propagation. Otherwise it doesn't matter. */ + if (g->gc.state == GCSpropagate || g->gc.state == GCSatomic) + gc_mark(g, v); /* Move frontier forward. */ + else + makewhite(g, o); /* Make it white to avoid the following barrier. */ +} + +/* Specialized barrier for closed upvalue. Pass &uv->tv. */ +void LJ_FASTCALL lj_gc_barrieruv(global_State *g, TValue *tv) +{ +#define TV2MARKED(x) \ + (*((uint8_t *)(x) - offsetof(GCupval, tv) + offsetof(GCupval, marked))) + if (g->gc.state == GCSpropagate || g->gc.state == GCSatomic) + gc_mark(g, gcV(tv)); + else + TV2MARKED(tv) = (TV2MARKED(tv) & (uint8_t)~LJ_GC_COLORS) | curwhite(g); +#undef TV2MARKED +} + +/* Close upvalue. Also needs a write barrier. */ +void lj_gc_closeuv(global_State *g, GCupval *uv) +{ + GCobj *o = obj2gco(uv); + /* Copy stack slot to upvalue itself and point to the copy. */ + copyTV(mainthread(g), &uv->tv, uvval(uv)); + setmref(uv->v, &uv->tv); + uv->closed = 1; + setgcrefr(o->gch.nextgc, g->gc.root); + setgcref(g->gc.root, o); + if (isgray(o)) { /* A closed upvalue is never gray, so fix this. */ + if (g->gc.state == GCSpropagate || g->gc.state == GCSatomic) { + gray2black(o); /* Make it black and preserve invariant. */ + if (tviswhite(&uv->tv)) + lj_gc_barrierf(g, o, gcV(&uv->tv)); + } else { + makewhite(g, o); /* Make it white, i.e. sweep the upvalue. */ + lj_assertG(g->gc.state != GCSfinalize && g->gc.state != GCSpause, + "bad GC state"); + } + } +} + +#if LJ_HASJIT +/* Mark a trace if it's saved during the propagation phase. */ +void lj_gc_barriertrace(global_State *g, uint32_t traceno) +{ + if (g->gc.state == GCSpropagate || g->gc.state == GCSatomic) + gc_marktrace(g, traceno); +} +#endif + +/* -- Allocator ----------------------------------------------------------- */ + +/* Call pluggable memory allocator to allocate or resize a fragment. */ +void *lj_mem_realloc(lua_State *L, void *p, GCSize osz, GCSize nsz) +{ + global_State *g = G(L); + lj_assertG((osz == 0) == (p == NULL), "realloc API violation"); + p = g->allocf(g->allocd, p, osz, nsz); + if (p == NULL && nsz > 0) + lj_err_mem(L); + lj_assertG((nsz == 0) == (p == NULL), "allocf API violation"); + lj_assertG(checkptrGC(p), + "allocated memory address %p outside required range", p); + g->gc.total = (g->gc.total - osz) + nsz; + return p; +} + +/* Allocate new GC object and link it to the root set. */ +void * LJ_FASTCALL lj_mem_newgco(lua_State *L, GCSize size) +{ + global_State *g = G(L); + GCobj *o = (GCobj *)g->allocf(g->allocd, NULL, 0, size); + if (o == NULL) + lj_err_mem(L); + lj_assertG(checkptrGC(o), + "allocated memory address %p outside required range", o); + g->gc.total += size; + setgcrefr(o->gch.nextgc, g->gc.root); + setgcref(g->gc.root, o); + newwhite(g, o); + return o; +} + +/* Resize growable vector. */ +void *lj_mem_grow(lua_State *L, void *p, MSize *szp, MSize lim, MSize esz) +{ + MSize sz = (*szp) << 1; + if (sz < LJ_MIN_VECSZ) + sz = LJ_MIN_VECSZ; + if (sz > lim) + sz = lim; + p = lj_mem_realloc(L, p, (*szp)*esz, sz*esz); + *szp = sz; + return p; +} + -- cgit v1.2.1