/script_binding/lua/lua/lgc.h
C++ Header | 110 lines | 60 code | 28 blank | 22 comment | 11 complexity | c24d8d859d1defa912e75d65a06e61c3 MD5 | raw file
1/* 2** $Id: lgc.h,v 2.15.1.1 2007/12/27 13:02:25 roberto Exp $ 3** Garbage Collector 4** See Copyright Notice in lua.h 5*/ 6 7#ifndef lgc_h 8#define lgc_h 9 10 11#include "lobject.h" 12 13 14/* 15** Possible states of the Garbage Collector 16*/ 17#define GCSpause 0 18#define GCSpropagate 1 19#define GCSsweepstring 2 20#define GCSsweep 3 21#define GCSfinalize 4 22 23 24/* 25** some userful bit tricks 26*/ 27#define resetbits(x,m) ((x) &= cast(lu_byte, ~(m))) 28#define setbits(x,m) ((x) |= (m)) 29#define testbits(x,m) ((x) & (m)) 30#define bitmask(b) (1<<(b)) 31#define bit2mask(b1,b2) (bitmask(b1) | bitmask(b2)) 32#define l_setbit(x,b) setbits(x, bitmask(b)) 33#define resetbit(x,b) resetbits(x, bitmask(b)) 34#define testbit(x,b) testbits(x, bitmask(b)) 35#define set2bits(x,b1,b2) setbits(x, (bit2mask(b1, b2))) 36#define reset2bits(x,b1,b2) resetbits(x, (bit2mask(b1, b2))) 37#define test2bits(x,b1,b2) testbits(x, (bit2mask(b1, b2))) 38 39 40 41/* 42** Layout for bit use in `marked' field: 43** bit 0 - object is white (type 0) 44** bit 1 - object is white (type 1) 45** bit 2 - object is black 46** bit 3 - for userdata: has been finalized 47** bit 3 - for tables: has weak keys 48** bit 4 - for tables: has weak values 49** bit 5 - object is fixed (should not be collected) 50** bit 6 - object is "super" fixed (only the main thread) 51*/ 52 53 54#define WHITE0BIT 0 55#define WHITE1BIT 1 56#define BLACKBIT 2 57#define FINALIZEDBIT 3 58#define KEYWEAKBIT 3 59#define VALUEWEAKBIT 4 60#define FIXEDBIT 5 61#define SFIXEDBIT 6 62#define WHITEBITS bit2mask(WHITE0BIT, WHITE1BIT) 63 64 65#define iswhite(x) test2bits((x)->gch.marked, WHITE0BIT, WHITE1BIT) 66#define isblack(x) testbit((x)->gch.marked, BLACKBIT) 67#define isgray(x) (!isblack(x) && !iswhite(x)) 68 69#define otherwhite(g) (g->currentwhite ^ WHITEBITS) 70#define isdead(g,v) ((v)->gch.marked & otherwhite(g) & WHITEBITS) 71 72#define changewhite(x) ((x)->gch.marked ^= WHITEBITS) 73#define gray2black(x) l_setbit((x)->gch.marked, BLACKBIT) 74 75#define valiswhite(x) (iscollectable(x) && iswhite(gcvalue(x))) 76 77#define luaC_white(g) cast(lu_byte, (g)->currentwhite & WHITEBITS) 78 79 80#define luaC_checkGC(L) { \ 81 condhardstacktests(luaD_reallocstack(L, L->stacksize - EXTRA_STACK - 1)); \ 82 if (G(L)->totalbytes >= G(L)->GCthreshold) \ 83 luaC_step(L); } 84 85 86#define luaC_barrier(L,p,v) { if (valiswhite(v) && isblack(obj2gco(p))) \ 87 luaC_barrierf(L,obj2gco(p),gcvalue(v)); } 88 89#define luaC_barriert(L,t,v) { if (valiswhite(v) && isblack(obj2gco(t))) \ 90 luaC_barrierback(L,t); } 91 92#define luaC_objbarrier(L,p,o) \ 93 { if (iswhite(obj2gco(o)) && isblack(obj2gco(p))) \ 94 luaC_barrierf(L,obj2gco(p),obj2gco(o)); } 95 96#define luaC_objbarriert(L,t,o) \ 97 { if (iswhite(obj2gco(o)) && isblack(obj2gco(t))) luaC_barrierback(L,t); } 98 99LUAI_FUNC size_t luaC_separateudata (lua_State *L, int all); 100LUAI_FUNC void luaC_callGCTM (lua_State *L); 101LUAI_FUNC void luaC_freeall (lua_State *L); 102LUAI_FUNC void luaC_step (lua_State *L); 103LUAI_FUNC void luaC_fullgc (lua_State *L); 104LUAI_FUNC void luaC_link (lua_State *L, GCObject *o, lu_byte tt); 105LUAI_FUNC void luaC_linkupval (lua_State *L, UpVal *uv); 106LUAI_FUNC void luaC_barrierf (lua_State *L, GCObject *o, GCObject *v); 107LUAI_FUNC void luaC_barrierback (lua_State *L, Table *t); 108 109 110#endif