From 4f88418170d298b065a7f71d86b1127153919ae9 Mon Sep 17 00:00:00 2001 From: Roberto Ierusalimschy Date: Fri, 17 Apr 2009 11:28:06 -0300 Subject: 'CallInfo' stack implemented as double-linked list instead of an array --- ldo.c | 69 +++++++++++++++++++++---------------------------------------------- 1 file changed, 21 insertions(+), 48 deletions(-) (limited to 'ldo.c') diff --git a/ldo.c b/ldo.c index 28560e0a..1a051222 100644 --- a/ldo.c +++ b/ldo.c @@ -1,5 +1,5 @@ /* -** $Id: ldo.c,v 2.58 2009/04/08 18:04:33 roberto Exp roberto $ +** $Id: ldo.c,v 2.59 2009/04/15 16:53:39 roberto Exp roberto $ ** Stack and Call structure of Lua ** See Copyright Notice in lua.h */ @@ -70,12 +70,8 @@ void luaD_seterrorobj (lua_State *L, int errcode, StkId oldtop) { static void restore_stack_limit (lua_State *L) { - lua_assert(L->stack_last - L->stack == L->stacksize - EXTRA_STACK - 1); - if (L->size_ci > LUAI_MAXCALLS) { /* there was an overflow? */ - int inuse = cast_int(L->ci - L->base_ci); - if (inuse + 1 < LUAI_MAXCALLS) /* can `undo' overflow? */ - luaD_reallocCI(L, LUAI_MAXCALLS); - } + if (L->nci >= LUAI_MAXCALLS) /* stack overflow? */ + luaE_freeCI(L); /* erase all extras CIs */ } @@ -124,7 +120,7 @@ static void correctstack (lua_State *L, TValue *oldstack) { L->top = (L->top - oldstack) + L->stack; for (up = L->openupval; up != NULL; up = up->gch.next) gco2uv(up)->v = (gco2uv(up)->v - oldstack) + L->stack; - for (ci = L->base_ci; ci <= L->ci; ci++) { + for (ci = L->ci; ci != NULL; ci = ci->previous) { ci->top = (ci->top - oldstack) + L->stack; ci->base = (ci->base - oldstack) + L->stack; ci->func = (ci->func - oldstack) + L->stack; @@ -144,15 +140,6 @@ void luaD_reallocstack (lua_State *L, int newsize) { } -void luaD_reallocCI (lua_State *L, int newsize) { - CallInfo *oldci = L->base_ci; - luaM_reallocvector(L, L->base_ci, L->size_ci, newsize, CallInfo); - L->size_ci = newsize; - L->ci = (L->ci - oldci) + L->base_ci; - L->end_ci = L->base_ci + L->size_ci - 1; -} - - void luaD_growstack (lua_State *L, int n) { if (n <= L->stacksize) /* double size is enough? */ luaD_reallocstack(L, 2*L->stacksize); @@ -161,18 +148,6 @@ void luaD_growstack (lua_State *L, int n) { } -static CallInfo *growCI (lua_State *L) { - if (L->size_ci > LUAI_MAXCALLS) /* overflow while handling overflow? */ - luaD_throw(L, LUA_ERRERR); - else { - luaD_reallocCI(L, 2*L->size_ci); - if (L->size_ci > LUAI_MAXCALLS) - luaG_runerror(L, "stack overflow"); - } - return ++L->ci; -} - - void luaD_callhook (lua_State *L, int event, int line) { lua_Hook hook = L->hook; if (hook && L->allowhook) { @@ -182,9 +157,9 @@ void luaD_callhook (lua_State *L, int event, int line) { ar.event = event; ar.currentline = line; if (event == LUA_HOOKTAILRET) - ar.i_ci = 0; /* tail call; no debug information about it */ + ar.i_ci = NULL; /* tail call; no debug information about it */ else - ar.i_ci = cast_int(L->ci - L->base_ci); + ar.i_ci = L->ci; luaD_checkstack(L, LUA_MINSTACK); /* ensure minimum stack size */ L->ci->top = L->top + LUA_MINSTACK; lua_assert(L->ci->top <= L->stack_last); @@ -235,9 +210,7 @@ static StkId tryfuncTM (lua_State *L, StkId func) { -#define inc_ci(L) \ - ((L->ci == L->end_ci) ? growCI(L) : \ - (condhardstacktests(luaD_reallocCI(L, L->size_ci)), ++L->ci)) +#define next_ci(L) (L->ci = (L->ci->next ? L->ci->next : luaE_extendCI(L))) /* @@ -265,7 +238,7 @@ int luaD_precall (lua_State *L, StkId func, int nresults) { base = adjust_varargs(L, p, nargs); func = restorestack(L, funcr); /* previous call may change the stack */ } - ci = inc_ci(L); /* now `enter' new function */ + ci = next_ci(L); /* now 'enter' new function */ ci->func = func; L->base = ci->base = base; ci->top = L->base + p->maxstacksize; @@ -287,7 +260,7 @@ int luaD_precall (lua_State *L, StkId func, int nresults) { CallInfo *ci; int n; luaD_checkstack(L, LUA_MINSTACK); /* ensure minimum stack size */ - ci = inc_ci(L); /* now `enter' new function */ + ci = next_ci(L); /* now 'enter' new function */ ci->func = restorestack(L, funcr); L->base = ci->base = ci->func + 1; ci->top = L->top + LUA_MINSTACK; @@ -318,17 +291,17 @@ static StkId callrethooks (lua_State *L, StkId firstResult) { int luaD_poscall (lua_State *L, StkId firstResult) { StkId res; int wanted, i; - CallInfo *ci; + CallInfo *ci = L->ci; if (L->hookmask & (LUA_MASKRET | LUA_MASKLINE)) { if (L->hookmask & LUA_MASKRET) firstResult = callrethooks(L, firstResult); - L->oldpc = (L->ci - 1)->savedpc; /* set 'oldpc' for returning function */ + L->oldpc = L->ci->previous->savedpc; /* 'oldpc' for returning function */ } - ci = L->ci--; res = ci->func; /* res == final position of 1st result */ - wanted = (ci - 1)->nresults; - L->base = (ci - 1)->base; /* restore base */ - L->savedpc = (ci - 1)->savedpc; /* restore savedpc */ + L->ci = ci = L->ci->previous; /* back to caller */ + wanted = ci->nresults; + L->base = ci->base; /* restore base */ + L->savedpc = ci->savedpc; /* restore savedpc */ /* move results to correct place */ for (i = wanted; i != 0 && firstResult < L->top; i--) setobjs2s(L, res++, firstResult++); @@ -387,7 +360,7 @@ static void finishCcall (lua_State *L) { static void unroll (lua_State *L, void *ud) { UNUSED(ud); for (;;) { - if (L->ci == L->base_ci) /* stack is empty? */ + if (L->ci == &L->base_ci) /* stack is empty? */ return; /* coroutine finished normally */ if (!isLua(L->ci)) /* C function? */ finishCcall(L); @@ -403,7 +376,7 @@ static void resume (lua_State *L, void *ud) { StkId firstArg = cast(StkId, ud); CallInfo *ci = L->ci; if (L->status == LUA_OK) { /* start coroutine? */ - lua_assert(ci == L->base_ci && firstArg > L->base); + lua_assert(ci == &L->base_ci && firstArg > L->base); if (!luaD_precall(L, firstArg - 1, LUA_MULTRET)) /* Lua function? */ luaV_execute(L); /* call it */ } @@ -437,7 +410,7 @@ static int resume_error (lua_State *L, const char *msg) { */ static CallInfo *findpcall (lua_State *L) { CallInfo *ci; - for (ci = L->ci; ci > L->base_ci; ci--) { /* search for first pcall */ + for (ci = L->ci; ci != NULL; ci = ci->previous) { /* search for a pcall */ if (ci->callstatus & CIST_YPCALL) return ci; } @@ -471,7 +444,7 @@ LUA_API int lua_resume (lua_State *L, int nargs) { if (L->status != LUA_YIELD) { if (L->status != LUA_OK) return resume_error(L, "cannot resume dead coroutine"); - else if (L->ci != L->base_ci) + else if (L->ci != &L->base_ci) return resume_error(L, "cannot resume non-suspended coroutine"); } luai_userstateresume(L, nargs); @@ -515,7 +488,7 @@ LUA_API int lua_yield (lua_State *L, int nresults) { int luaD_pcall (lua_State *L, Pfunc func, void *u, ptrdiff_t old_top, ptrdiff_t ef) { int status; - ptrdiff_t old_ci = saveci(L, L->ci); + CallInfo *old_ci = L->ci; lu_byte old_allowhooks = L->allowhook; unsigned short old_nny = L->nny; ptrdiff_t old_errfunc = L->errfunc; @@ -525,7 +498,7 @@ int luaD_pcall (lua_State *L, Pfunc func, void *u, StkId oldtop = restorestack(L, old_top); luaF_close(L, oldtop); /* close possible pending closures */ luaD_seterrorobj(L, status, oldtop); - L->ci = restoreci(L, old_ci); + L->ci = old_ci; L->base = L->ci->base; L->savedpc = L->ci->savedpc; L->allowhook = old_allowhooks; -- cgit v1.2.3-55-g6feb