better document smart match overloading

[perl5.git] / perly.c

diff --git a/perly.c b/perly.c
index 94da31f..eff36d1 100644 (file)
--- 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, 2008 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.
@@ -111,7 +111,7 @@ yy_stack_print (pTHX_ const yy_parser *parser)
 
     PerlIO_printf(Perl_debug_log, "\nindex:");
     for (ps = min; ps <= parser->ps; ps++)
-       PerlIO_printf(Perl_debug_log, " %8d", ps - parser->stack);
+       PerlIO_printf(Perl_debug_log, " %8d", (int)(ps - parser->stack));
 
     PerlIO_printf(Perl_debug_log, "\nstate:");
     for (ps = min; ps <= parser->ps; ps++)
@@ -193,7 +193,7 @@ static void
 S_clear_yystack(pTHX_  const yy_parser *parser)
 {
     yy_stack_frame *ps     = parser->ps;
-    int i;
+    int i = 0;
 
     if (!parser->stack || ps == parser->stack)
        return;
@@ -258,11 +258,21 @@ S_clear_yystack(pTHX_  const yy_parser *parser)
      *   * 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++) {
+       LEAVE_SCOPE(ps[-i].savestack_ix);
        if (yy_type_tab[yystos[ps[-i].state]] == toketype_opval
            && ps[-i].val.opval) {
            if ( ! (ps[-i].val.opval->op_attached
@@ -275,10 +285,12 @@ S_clear_yystack(pTHX_  const yy_parser *parser)
            }
        }
     }
+#endif
 
     /* now free whole the stack, including the just-reduced ops */
 
     while (ps > parser->stack) {
+       LEAVE_SCOPE(ps->savestack_ix);
        if (yy_type_tab[yystos[ps->state]] == toketype_opval
            && ps->val.opval)
        {
@@ -286,25 +298,16 @@ S_clear_yystack(pTHX_  const yy_parser *parser)
                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--;
     }
 }
 
-/* delete a parser object */
-
-#ifndef PERL_IN_MADLY_C
-void
-Perl_parser_free(pTHX_  const yy_parser *parser)
-{
-    S_clear_yystack(aTHX_ parser);
-    Safefree(parser->stack);
-    PL_parser = parser->old_parser;
-}
-#endif
 
 /*----------.
 | yyparse.  |
@@ -347,8 +350,8 @@ Perl_yyparse (pTHX)
     parser = PL_parser;
     ps = parser->ps;
 
-    ENTER;  /* force parser free before we return */
-    SAVEDESTRUCTOR_X(Perl_parser_free, (void*) parser);
+    ENTER;  /* force parser stack cleanup before we return */
+    SAVEDESTRUCTOR_X(S_clear_yystack, parser);
 
 /*------------------------------------------------------------.
 | yynewstate -- Push a new state, which is found in yystate.  |
@@ -359,10 +362,12 @@ 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;
 
@@ -372,7 +377,7 @@ Perl_yyparse (pTHX)
        /* 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;
            Renew(parser->stack, parser->stack_size, yy_stack_frame);
@@ -447,6 +452,7 @@ Perl_yyparse (pTHX)
     ps->state   = yyn;
     ps->val     = parser->yylval;
     ps->comppad = PL_comppad;
+    ps->savestack_ix = PL_savestack_ix;
 #ifdef DEBUGGING
     ps->name    = (const char *)(yytname[yytoken]);
 #endif
@@ -519,6 +525,7 @@ 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 */
     {
@@ -533,6 +540,7 @@ Perl_yyparse (pTHX)
            }
        }
     }
+#endif
 
     parser->ps = ps -= (parser->yylen-1);
 
@@ -542,6 +550,7 @@ Perl_yyparse (pTHX)
 
     ps->val     = yyval;
     ps->comppad = PL_comppad;
+    ps->savestack_ix = PL_savestack_ix;
 #ifdef DEBUGGING
     ps->name    = (const char *)(yytname [yyr1[yyn]]);
 #endif
@@ -579,6 +588,7 @@ Perl_yyparse (pTHX)
            /* Pop the rest of the stack.  */
            while (ps > parser->stack) {
                YYDSYMPRINTF ("Error: popping", yystos[ps->state], &ps->val);
+               LEAVE_SCOPE(ps->savestack_ix);
                if (yy_type_tab[yystos[ps->state]] == toketype_opval
                        && ps->val.opval)
                {
@@ -626,6 +636,7 @@ Perl_yyparse (pTHX)
            YYABORT;
 
        YYDSYMPRINTF ("Error: popping", yystos[ps->state], &ps->val);
+       LEAVE_SCOPE(ps->savestack_ix);
        if (yy_type_tab[yystos[ps->state]] == toketype_opval && ps->val.opval) {
            YYDPRINTF ((Perl_debug_log, "(freeing op)\n"));
            if (ps->comppad != PL_comppad) {
@@ -649,6 +660,7 @@ Perl_yyparse (pTHX)
     ps->state   = yyn;
     ps->val     = parser->yylval;
     ps->comppad = PL_comppad;
+    ps->savestack_ix = PL_savestack_ix;
 #ifdef DEBUGGING
     ps->name    ="<err>";
 #endif
@@ -672,7 +684,7 @@ Perl_yyparse (pTHX)
     goto yyreturn;
 
   yyreturn:
-    LEAVE;                     /* force parser free before we return */
+    LEAVE;     /* force parser stack cleanup before we return */
     return yyresult;
 }