X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=perly.c;h=95779a014d1f94931cb37aba7563ad8f7ad306ac;hb=12bd6ede29d13c215438daf78d15695e487886b0;hp=016c7d7cdc5755a58cf40ea712637f4b813d1d3e;hpb=714c8e96dde801b3b2e73fc130d02c78db1eb06f;p=p5sagit%2Fp5-mst-13.2.git

diff --git a/perly.c b/perly.c
index 016c7d7..95779a0 100644
--- a/perly.c
+++ b/perly.c
@@ -1,6 +1,6 @@
 /*    perly.c
  *
- *    Copyright (c) 2004, 2005, 2006 Larry Wall and others
+ *    Copyright (c) 2004, 2005, 2006, 2007, by Larry Wall and others
  *
  *    You may distribute under the terms of either the GNU General Public
  *    License or the Artistic License, as specified in the README file.
@@ -45,7 +45,6 @@ typedef signed char yysigned_char;
 
 # define YYSIZE_T size_t
 
-#define YYEMPTY		(-2)
 #define YYEOF		0
 #define YYTERROR	1
 
@@ -107,12 +106,12 @@ yy_stack_print (pTHX_ const yy_parser *parser)
     const yy_stack_frame *ps, *min;
 
     min = parser->ps - 8 + 1;
-    if (min <= &parser->stack[0])
-	min = &parser->stack[0] + 1;
+    if (min <= parser->stack)
+	min = parser->stack + 1;
 
     PerlIO_printf(Perl_debug_log, "\nindex:");
     for (ps = min; ps <= parser->ps; ps++)
-	PerlIO_printf(Perl_debug_log, " %8d", ps - &parser->stack[0]);
+	PerlIO_printf(Perl_debug_log, " %8d", (int)(ps - parser->stack));
 
     PerlIO_printf(Perl_debug_log, "\nstate:");
     for (ps = min; ps <= parser->ps; ps++)
@@ -187,21 +186,16 @@ do {					\
 #  define YY_REDUCE_PRINT(Rule)
 #endif /* !DEBUGGING */
 
-
-/* YYINITDEPTH -- initial size of the parser's stacks.  */
-#define YYINITDEPTH 200
-
 /* called during cleanup (via SAVEDESTRUCTOR_X) to free any items on the
  * parse stack, thus avoiding leaks if we die  */
 
 static void
-S_clear_yystack(pTHX_ const void *p)
+S_clear_yystack(pTHX_  const yy_parser *parser)
 {
-    yy_parser      *parser = (yy_parser*) SvPVX((SV*)p);
     yy_stack_frame *ps     = parser->ps;
     int i;
 
-    if (ps == &parser->stack[0])
+    if (!parser->stack || ps == parser->stack)
 	return;
 
     YYDPRINTF ((Perl_debug_log, "clearing the parse stack\n"));
@@ -264,8 +258,17 @@ S_clear_yystack(pTHX_ const void *p)
      *   * a CV
      * but this would involve reworking all code (core and external) that
      * manipulate op trees.
-     */
+     *
+     * XXX DAPM 17/1/07 I've decided its too fragile for now, and so have
+     * disabled it */
+
+#define DISABLE_STACK_FREE
 
+
+#ifdef DISABLE_STACK_FREE
+    ps -= parser->yylen;
+    PERL_UNUSED_VAR(i);
+#else
     /* clear any reducing ops (1st pass) */
 
     for (i=0; i< parser->yylen; i++) {
@@ -281,10 +284,11 @@ S_clear_yystack(pTHX_ const void *p)
 	    }
 	}
     }
+#endif
 
     /* now free whole the stack, including the just-reduced ops */
 
-    while (ps > &parser->stack[0]) {
+    while (ps > parser->stack) {
 	if (yy_type_tab[yystos[ps->state]] == toketype_opval
 	    && ps->val.opval)
 	{
@@ -292,8 +296,10 @@ S_clear_yystack(pTHX_ const void *p)
 		PAD_RESTORE_LOCAL(ps->comppad);
 	    }
 	    YYDPRINTF ((Perl_debug_log, "(freeing op)\n"));
+#ifndef DISABLE_STACK_FREE
 	    ps->val.opval->op_latefree  = 0;
 	    if (!(ps->val.opval->op_attached && !ps->val.opval->op_latefreed))
+#endif
 		op_free(ps->val.opval);
 	}
 	ps--;
@@ -301,7 +307,6 @@ S_clear_yystack(pTHX_ const void *p)
 }
 
 
-
 /*----------.
 | yyparse.  |
 `----------*/
@@ -321,14 +326,13 @@ Perl_yyparse (pTHX)
     /* Lookahead token as an internal (translated) token number.  */
     int yytoken = 0;
 
-    SV *parser_sv;		    /* SV whose PVX holds the parser object */
     register yy_parser *parser;	    /* the parser object */
     register yy_stack_frame  *ps;   /* current parser stack frame */
 
 #define YYPOPSTACK   parser->ps = --ps
 #define YYPUSHSTACK  parser->ps = ++ps
 
-    /* The variables used to return semantic value and location from the
+    /* The variable used to return semantic value and location from the
 	  action routines: ie $$.  */
     YYSTYPE yyval;
 
@@ -341,25 +345,11 @@ Perl_yyparse (pTHX)
 
     YYDPRINTF ((Perl_debug_log, "Starting parse\n"));
 
-    ENTER;			/* force stack free before we return */
-    SAVEVPTR(PL_parser);
-
-    parser_sv = newSV(sizeof(yy_parser)
-			+ (YYINITDEPTH-1) * sizeof(yy_stack_frame));
-    SAVEFREESV(parser_sv);
-    PL_parser = parser = (yy_parser*)  SvPVX(parser_sv);
-    ps = (yy_stack_frame*) &parser->stack[0];
-    parser->ps = ps;
-
-    parser->stack_size = YYINITDEPTH;
-
-    /* cleanup the parse stack on premature exit */
-    SAVEDESTRUCTOR_X(S_clear_yystack, (void*) parser_sv);
+    parser = PL_parser;
+    ps = parser->ps;
 
-
-    ps->state = 0;
-    parser->yyerrstatus = 0;
-    parser->yychar = YYEMPTY;		/* Cause a token to be read.  */
+    ENTER;  /* force parser stack cleanup before we return */
+    SAVEDESTRUCTOR_X(S_clear_yystack, parser);
 
 /*------------------------------------------------------------.
 | yynewstate -- Push a new state, which is found in yystate.  |
@@ -370,28 +360,26 @@ Perl_yyparse (pTHX)
 
     YYDPRINTF ((Perl_debug_log, "Entering state %d\n", yystate));
 
+#ifndef DISABLE_STACK_FREE
     if (yy_type_tab[yystos[yystate]] == toketype_opval && ps->val.opval) {
 	ps->val.opval->op_latefree  = 1;
 	ps->val.opval->op_latefreed = 0;
     }
+#endif
 
     parser->yylen = 0;
 
     {
-	size_t size = ps - &parser->stack[0] + 1;
+	size_t size = ps - parser->stack + 1;
 
 	/* grow the stack? We always leave 1 spare slot,
 	 * in case of a '' -> 'foo' reduction */
 
-	if (size >= parser->stack_size - 1) {
+	if (size >= (size_t)parser->stack_size - 1) {
 	    /* this will croak on insufficient memory */
 	    parser->stack_size *= 2;
-	    PL_parser = parser =
-			(yy_parser*) SvGROW(parser_sv, sizeof(yy_parser)
-			    + (parser->stack_size-1) * sizeof(yy_stack_frame));
-
-	    /* readdress any pointers into realloced parser object */
-	    ps = parser->ps = &parser->stack[0] + size -1;
+	    Renew(parser->stack, parser->stack_size, yy_stack_frame);
+	    ps = parser->ps = parser->stack + size -1;
 
 	    YYDPRINTF((Perl_debug_log,
 			    "parser stack size increased to %lu frames\n",
@@ -534,6 +522,7 @@ Perl_yyparse (pTHX)
 
     }
 
+#ifndef DISABLE_STACK_FREE
     /* any just-reduced ops with the op_latefreed flag cleared need to be
      * freed; the rest need the flag resetting */
     {
@@ -548,6 +537,7 @@ Perl_yyparse (pTHX)
 	    }
 	}
     }
+#endif
 
     parser->ps = ps -= (parser->yylen-1);
 
@@ -592,7 +582,7 @@ Perl_yyparse (pTHX)
 	    /* Pop the error token.  */
 	    YYPOPSTACK;
 	    /* Pop the rest of the stack.  */
-	    while (ps > &parser->stack[0]) {
+	    while (ps > parser->stack) {
 		YYDSYMPRINTF ("Error: popping", yystos[ps->state], &ps->val);
 		if (yy_type_tab[yystos[ps->state]] == toketype_opval
 			&& ps->val.opval)
@@ -637,7 +627,7 @@ Perl_yyparse (pTHX)
 	}
 
 	/* Pop the current state because it cannot handle the error token.  */
-	if (ps == &parser->stack[0])
+	if (ps == parser->stack)
 	    YYABORT;
 
 	YYDSYMPRINTF ("Error: popping", yystos[ps->state], &ps->val);
@@ -676,7 +666,7 @@ Perl_yyparse (pTHX)
   `-------------------------------------*/
   yyacceptlab:
     yyresult = 0;
-    parser->ps = &parser->stack[0]; /* disable cleanup */
+    parser->ps = parser->stack; /* disable cleanup */
     goto yyreturn;
 
   /*-----------------------------------.
@@ -687,7 +677,7 @@ Perl_yyparse (pTHX)
     goto yyreturn;
 
   yyreturn:
-    LEAVE;			/* force stack free before we return */
+    LEAVE;	/* force parser stack cleanup before we return */
     return yyresult;
 }