From 8ef9e8460e775793f760deb28d0c3d10dda31b49 Mon Sep 17 00:00:00 2001 From: Roberto Ierusalimschy Date: Fri, 30 Aug 2013 13:01:37 -0300 Subject: bug (GC can collect long identifier during parser) + change (using a single constant table for all functions in a chunk) --- lparser.c | 45 +++++++++++++++++---------------------------- 1 file changed, 17 insertions(+), 28 deletions(-) (limited to 'lparser.c') diff --git a/lparser.c b/lparser.c index c2386b82..0f53ff7c 100644 --- a/lparser.c +++ b/lparser.c @@ -1,5 +1,5 @@ /* -** $Id: lparser.c,v 2.133 2013/04/26 13:07:53 roberto Exp roberto $ +** $Id: lparser.c,v 2.134 2013/08/16 18:55:49 roberto Exp roberto $ ** Lua Parser ** See Copyright Notice in lua.h */ @@ -35,6 +35,10 @@ #define hasmultret(k) ((k) == VCALL || (k) == VVARARG) +/* because all strings are unified by the scanner, the parser + can use pointer equality for string equality */ +#define eqstr(a,b) ((a) == (b)) + /* ** nodes for block list (list of active blocks) @@ -57,16 +61,6 @@ static void statement (LexState *ls); static void expr (LexState *ls, expdesc *v); -static void anchor_token (LexState *ls) { - /* last token from outer function must be EOS */ - lua_assert(ls->fs != NULL || ls->t.token == TK_EOS); - if (ls->t.token == TK_NAME || ls->t.token == TK_STRING) { - TString *ts = ls->t.seminfo.ts; - luaX_newstring(ls, getstr(ts), ts->tsv.len); - } -} - - /* semantic error */ static l_noret semerror (LexState *ls, const char *msg) { ls->t.token = 0; /* remove 'near to' from final message */ @@ -222,7 +216,7 @@ static int searchupvalue (FuncState *fs, TString *name) { int i; Upvaldesc *up = fs->f->upvalues; for (i = 0; i < fs->nups; i++) { - if (luaS_eqstr(up[i].name, name)) return i; + if (eqstr(up[i].name, name)) return i; } return -1; /* not found */ } @@ -246,7 +240,7 @@ static int newupvalue (FuncState *fs, TString *name, expdesc *v) { static int searchvar (FuncState *fs, TString *n) { int i; for (i = cast_int(fs->nactvar) - 1; i >= 0; i--) { - if (luaS_eqstr(n, getlocvar(fs, i)->varname)) + if (eqstr(n, getlocvar(fs, i)->varname)) return i; } return -1; /* not found */ @@ -342,7 +336,7 @@ static void closegoto (LexState *ls, int g, Labeldesc *label) { FuncState *fs = ls->fs; Labellist *gl = &ls->dyd->gt; Labeldesc *gt = &gl->arr[g]; - lua_assert(luaS_eqstr(gt->name, label->name)); + lua_assert(eqstr(gt->name, label->name)); if (gt->nactvar < label->nactvar) { TString *vname = getlocvar(fs, gt->nactvar)->varname; const char *msg = luaO_pushfstring(ls->L, @@ -369,7 +363,7 @@ static int findlabel (LexState *ls, int g) { /* check labels in current block for a match */ for (i = bl->firstlabel; i < dyd->label.n; i++) { Labeldesc *lb = &dyd->label.arr[i]; - if (luaS_eqstr(lb->name, gt->name)) { /* correct label? */ + if (eqstr(lb->name, gt->name)) { /* correct label? */ if (gt->nactvar > lb->nactvar && (bl->upval || dyd->label.n > bl->firstlabel)) luaK_patchclose(ls->fs, gt->pc, lb->nactvar); @@ -403,7 +397,7 @@ static void findgotos (LexState *ls, Labeldesc *lb) { Labellist *gl = &ls->dyd->gt; int i = ls->fs->bl->firstgoto; while (i < gl->n) { - if (luaS_eqstr(gl->arr[i].name, lb->name)) + if (eqstr(gl->arr[i].name, lb->name)) closegoto(ls, i, lb); else i++; @@ -525,7 +519,6 @@ static void codeclosure (LexState *ls, expdesc *v) { static void open_func (LexState *ls, FuncState *fs, BlockCnt *bl) { - lua_State *L = ls->L; Proto *f; fs->prev = ls->fs; /* linked list of funcstates */ fs->ls = ls; @@ -544,10 +537,6 @@ static void open_func (LexState *ls, FuncState *fs, BlockCnt *bl) { f = fs->f; f->source = ls->source; f->maxstacksize = 2; /* registers 0/1 are always valid */ - fs->h = luaH_new(L); - /* anchor table of constants (to avoid being collected) */ - sethvalue2s(L, L->top, fs->h); - incr_top(L); enterblock(fs, bl, 0); } @@ -572,9 +561,6 @@ static void close_func (LexState *ls) { f->sizeupvalues = fs->nups; lua_assert(fs->bl == NULL); ls->fs = fs->prev; - /* last token read was anchored in defunct function; must re-anchor it */ - anchor_token(ls); - L->top--; /* pop table of constants */ luaC_checkGC(L); } @@ -1202,7 +1188,7 @@ static void gotostat (LexState *ls, int pc) { static void checkrepeated (FuncState *fs, Labellist *ll, TString *label) { int i; for (i = fs->bl->firstlabel; i < ll->n; i++) { - if (luaS_eqstr(label, ll->arr[i].name)) { + if (eqstr(label, ll->arr[i].name)) { const char *msg = luaO_pushfstring(fs->ls->L, "label " LUA_QS " already defined on line %d", getstr(label), ll->arr[i].line); @@ -1627,8 +1613,10 @@ Closure *luaY_parser (lua_State *L, ZIO *z, Mbuffer *buff, LexState lexstate; FuncState funcstate; Closure *cl = luaF_newLclosure(L, 1); /* create main closure */ - /* anchor closure (to avoid being collected) */ - setclLvalue(L, L->top, cl); + setclLvalue(L, L->top, cl); /* anchor it (to avoid being collected) */ + incr_top(L); + lexstate.h = luaH_new(L); /* create table for scanner */ + sethvalue(L, L->top, lexstate.h); /* anchor it */ incr_top(L); funcstate.f = cl->l.p = luaF_newproto(L); funcstate.f->source = luaS_new(L, name); /* create and anchor TString */ @@ -1641,6 +1629,7 @@ Closure *luaY_parser (lua_State *L, ZIO *z, Mbuffer *buff, lua_assert(!funcstate.prev && funcstate.nups == 1 && !lexstate.fs); /* all scopes should be correctly finished */ lua_assert(dyd->actvar.n == 0 && dyd->gt.n == 0 && dyd->label.n == 0); - return cl; /* it's on the stack too */ + L->top--; /* remove scanner's table */ + return cl; /* closure is on the stack, too */ } -- cgit v1.2.3-55-g6feb