3 * Copyright (c) 2004, 2005, 2006 Larry Wall and others
5 * You may distribute under the terms of either the GNU General Public
6 * License or the Artistic License, as specified in the README file.
8 * Note that this file was originally generated as an output from
9 * GNU bison version 1.875, but now the code is statically maintained
10 * and edited; the bits that are dependent on perly.y are now
11 * #included from the files perly.tab and perly.act.
13 * Here is an important copyright statement from the original, generated
16 * As a special exception, when this file is copied by Bison into a
17 * Bison output file, you may use that output file without
18 * restriction. This special exception was added by the Free
19 * Software Foundation in version 1.24 of Bison.
21 * Note that this file is also #included in madly.c, to allow compilation
22 * of a second parser, Perl_madparse, that is identical to Perl_yyparse,
23 * but which includes extra code for dumping the parse tree.
24 * This is controlled by the PERL_IN_MADLY_C define.
28 #define PERL_IN_PERLY_C
31 typedef unsigned char yytype_uint8;
32 typedef signed char yytype_int8;
33 typedef unsigned short int yytype_uint16;
34 typedef short int yytype_int16;
35 typedef signed char yysigned_char;
43 /* contains all the parser state tables; auto-generated from perly.y */
46 # define YYSIZE_T size_t
52 #define YYACCEPT goto yyacceptlab
53 #define YYABORT goto yyabortlab
54 #define YYERROR goto yyerrlab1
56 /* Enable debugging if requested. */
59 # define yydebug (DEBUG_p_TEST)
61 # define YYFPRINTF PerlIO_printf
63 # define YYDPRINTF(Args) \
69 # define YYDSYMPRINTF(Title, Token, Value) \
72 YYFPRINTF (Perl_debug_log, "%s ", Title); \
73 yysymprint (aTHX_ Perl_debug_log, Token, Value); \
74 YYFPRINTF (Perl_debug_log, "\n"); \
78 /*--------------------------------.
79 | Print this symbol on YYOUTPUT. |
80 `--------------------------------*/
83 yysymprint(pTHX_ PerlIO * const yyoutput, int yytype, const YYSTYPE * const yyvaluep)
85 if (yytype < YYNTOKENS) {
86 YYFPRINTF (yyoutput, "token %s (", yytname[yytype]);
88 YYPRINT (yyoutput, yytoknum[yytype], *yyvaluep);
90 YYFPRINTF (yyoutput, "0x%"UVxf, (UV)yyvaluep->ival);
94 YYFPRINTF (yyoutput, "nterm %s (", yytname[yytype]);
96 YYFPRINTF (yyoutput, ")");
101 * print the top 8 items on the parse stack.
105 yy_stack_print (pTHX_ const yy_parser *parser)
107 const yy_stack_frame *ps, *min;
109 min = parser->ps - 8 + 1;
110 if (min <= parser->stack)
111 min = parser->stack + 1;
113 PerlIO_printf(Perl_debug_log, "\nindex:");
114 for (ps = min; ps <= parser->ps; ps++)
115 PerlIO_printf(Perl_debug_log, " %8d", ps - parser->stack);
117 PerlIO_printf(Perl_debug_log, "\nstate:");
118 for (ps = min; ps <= parser->ps; ps++)
119 PerlIO_printf(Perl_debug_log, " %8d", ps->state);
121 PerlIO_printf(Perl_debug_log, "\ntoken:");
122 for (ps = min; ps <= parser->ps; ps++)
123 PerlIO_printf(Perl_debug_log, " %8.8s", ps->name);
125 PerlIO_printf(Perl_debug_log, "\nvalue:");
126 for (ps = min; ps <= parser->ps; ps++) {
127 switch (yy_type_tab[yystos[ps->state]]) {
129 PerlIO_printf(Perl_debug_log, " %8.8s",
131 ? PL_op_name[ps->val.opval->op_type]
135 #ifndef PERL_IN_MADLY_C
136 case toketype_p_tkval:
137 PerlIO_printf(Perl_debug_log, " %8.8s",
138 ps->val.pval ? ps->val.pval : "(NULL)");
141 case toketype_i_tkval:
144 PerlIO_printf(Perl_debug_log, " %8"IVdf, (IV)ps->val.ival);
147 PerlIO_printf(Perl_debug_log, " %8"UVxf, (UV)ps->val.ival);
150 PerlIO_printf(Perl_debug_log, "\n\n");
153 # define YY_STACK_PRINT(parser) \
155 if (yydebug && DEBUG_v_TEST) \
156 yy_stack_print (aTHX_ parser); \
160 /*------------------------------------------------.
161 | Report that the YYRULE is going to be reduced. |
162 `------------------------------------------------*/
165 yy_reduce_print (pTHX_ int yyrule)
168 const unsigned int yylineno = yyrline[yyrule];
169 YYFPRINTF (Perl_debug_log, "Reducing stack by rule %d (line %u), ",
170 yyrule - 1, yylineno);
171 /* Print the symbols being reduced, and their result. */
172 for (yyi = yyprhs[yyrule]; 0 <= yyrhs[yyi]; yyi++)
173 YYFPRINTF (Perl_debug_log, "%s ", yytname [yyrhs[yyi]]);
174 YYFPRINTF (Perl_debug_log, "-> %s\n", yytname [yyr1[yyrule]]);
177 # define YY_REDUCE_PRINT(Rule) \
180 yy_reduce_print (aTHX_ Rule); \
183 #else /* !DEBUGGING */
184 # define YYDPRINTF(Args)
185 # define YYDSYMPRINTF(Title, Token, Value)
186 # define YY_STACK_PRINT(parser)
187 # define YY_REDUCE_PRINT(Rule)
188 #endif /* !DEBUGGING */
190 /* YYINITDEPTH -- initial size of the parser's stacks. */
191 #define YYINITDEPTH 200
193 /* called during cleanup (via SAVEDESTRUCTOR_X) to free any items on the
194 * parse stack, thus avoiding leaks if we die */
197 S_clear_yystack(pTHX_ const yy_parser *parser)
199 yy_stack_frame *ps = parser->ps;
202 if (ps == parser->stack)
205 YYDPRINTF ((Perl_debug_log, "clearing the parse stack\n"));
207 /* Freeing ops on the stack, and the op_latefree / op_latefreed /
210 * When we pop tokens off the stack during error recovery, or when
211 * we pop all the tokens off the stack after a die during a shift or
212 * reduce (i.e. Perl_croak somewhere in yylex() or in one of the
213 * newFOO() functions), then it's possible that some of these tokens are
214 * of type opval, pointing to an OP. All these ops are orphans; each is
215 * its own miniature subtree that has not yet been attached to a
216 * larger tree. In this case, we should clearly free the op (making
217 * sure, for each op we free that we have PL_comppad pointing to the
218 * right place for freeing any SVs attached to the op in threaded
221 * However, there is a particular problem if we die in newFOO() called
222 * by a reducing action; e.g.
225 * { $$ = newFOO($1,$2,$3) }
228 * OP *newFOO { ....; if (...) croak; .... }
230 * In this case, when we come to clean bar baz and boz off the stack,
231 * we don't know whether newFOO() has already:
234 * * attached them to part of a larger tree
235 * * attached them to PL_compcv
236 * * attached them to PL_compcv then freed it (as in BEGIN {die } )
238 * To get round this problem, we set the flag op_latefree on every op
239 * that gets pushed onto the parser stack. If op_free() sees this
240 * flag, it clears the op and frees any children,, but *doesn't* free
241 * the op itself; instead it sets the op_latefreed flag. This means
242 * that we can safely call op_free() multiple times on each stack op.
243 * So, when clearing the stack, we first, for each op that was being
244 * reduced, call op_free with op_latefree=1. This ensures that all ops
245 * hanging off these op are freed, but the reducing ops themselces are
246 * just undefed. Then we set op_latefreed=0 on *all* ops on the stack
247 * and free them. A little thought should convince you that this
248 * two-part approach to the reducing ops should handle the first three
249 * cases above safely.
251 * In the case of attaching to PL_compcv (currently just newATTRSUB
252 * does this), then we set the op_attached flag on the op that has
253 * been so attached, then avoid doing the final op_free during
254 * cleanup, on the assumption that it will happen (or has already
255 * happened) when PL_compcv is freed.
257 * Note this is fairly fragile mechanism. A more robust approach
258 * would be to use two of these flag bits as 2-bit reference count
259 * field for each op, indicating whether it is pointed to from:
263 * but this would involve reworking all code (core and external) that
264 * manipulate op trees.
267 /* clear any reducing ops (1st pass) */
269 for (i=0; i< parser->yylen; i++) {
270 if (yy_type_tab[yystos[ps[-i].state]] == toketype_opval
271 && ps[-i].val.opval) {
272 if ( ! (ps[-i].val.opval->op_attached
273 && !ps[-i].val.opval->op_latefreed))
275 if (ps[-i].comppad != PL_comppad) {
276 PAD_RESTORE_LOCAL(ps[-i].comppad);
278 op_free(ps[-i].val.opval);
283 /* now free whole the stack, including the just-reduced ops */
285 while (ps > parser->stack) {
286 if (yy_type_tab[yystos[ps->state]] == toketype_opval
289 if (ps->comppad != PL_comppad) {
290 PAD_RESTORE_LOCAL(ps->comppad);
292 YYDPRINTF ((Perl_debug_log, "(freeing op)\n"));
293 ps->val.opval->op_latefree = 0;
294 if (!(ps->val.opval->op_attached && !ps->val.opval->op_latefreed))
295 op_free(ps->val.opval);
301 /* delete a parser object */
304 S_parser_free(pTHX_ const yy_parser *parser)
306 S_clear_yystack(aTHX_ parser);
307 Safefree(parser->stack);
308 PL_parser = parser->old_parser;
317 #ifdef PERL_IN_MADLY_C
324 register int yystate;
328 /* Lookahead token as an internal (translated) token number. */
331 register yy_parser *parser; /* the parser object */
332 register yy_stack_frame *ps; /* current parser stack frame */
334 #define YYPOPSTACK parser->ps = --ps
335 #define YYPUSHSTACK parser->ps = ++ps
337 /* The variables used to return semantic value and location from the
338 action routines: ie $$. */
341 #ifndef PERL_IN_MADLY_C
348 YYDPRINTF ((Perl_debug_log, "Starting parse\n"));
350 Newx(parser, 1, yy_parser);
351 parser->old_parser = PL_parser;
354 Newx(ps, YYINITDEPTH, yy_stack_frame);
357 parser->stack_size = YYINITDEPTH;
359 ENTER; /* force parser free before we return */
360 SAVEDESTRUCTOR_X(S_parser_free, (void*) parser);
364 parser->yyerrstatus = 0;
365 parser->yychar = YYEMPTY; /* Cause a token to be read. */
367 /*------------------------------------------------------------.
368 | yynewstate -- Push a new state, which is found in yystate. |
369 `------------------------------------------------------------*/
374 YYDPRINTF ((Perl_debug_log, "Entering state %d\n", yystate));
376 if (yy_type_tab[yystos[yystate]] == toketype_opval && ps->val.opval) {
377 ps->val.opval->op_latefree = 1;
378 ps->val.opval->op_latefreed = 0;
384 size_t size = ps - parser->stack + 1;
386 /* grow the stack? We always leave 1 spare slot,
387 * in case of a '' -> 'foo' reduction */
389 if (size >= parser->stack_size - 1) {
390 /* this will croak on insufficient memory */
391 parser->stack_size *= 2;
392 Renew(parser->stack, parser->stack_size, yy_stack_frame);
393 ps = parser->ps = parser->stack + size -1;
395 YYDPRINTF((Perl_debug_log,
396 "parser stack size increased to %lu frames\n",
397 (unsigned long int)parser->stack_size));
401 /* Do appropriate processing given the current state. */
402 /* Read a lookahead token if we need one and don't already have one. */
404 /* First try to decide what to do without reference to lookahead token. */
406 yyn = yypact[yystate];
407 if (yyn == YYPACT_NINF)
410 /* Not known => get a lookahead token if don't already have one. */
412 /* YYCHAR is either YYEMPTY or YYEOF or a valid lookahead symbol. */
413 if (parser->yychar == YYEMPTY) {
414 YYDPRINTF ((Perl_debug_log, "Reading a token: "));
415 #ifdef PERL_IN_MADLY_C
416 parser->yychar = PL_madskills ? madlex() : yylex();
418 parser->yychar = yylex();
422 if (parser->yychar >= 0 && parser->yychar < 255) {
423 parser->yychar = NATIVE_TO_ASCII(parser->yychar);
428 if (parser->yychar <= YYEOF) {
429 parser->yychar = yytoken = YYEOF;
430 YYDPRINTF ((Perl_debug_log, "Now at end of input.\n"));
433 yytoken = YYTRANSLATE (parser->yychar);
434 YYDSYMPRINTF ("Next token is", yytoken, &parser->yylval);
437 /* If the proper action on seeing token YYTOKEN is to reduce or to
438 detect an error, take that action. */
440 if (yyn < 0 || YYLAST < yyn || yycheck[yyn] != yytoken)
444 if (yyn == 0 || yyn == YYTABLE_NINF)
453 /* Shift the lookahead token. */
454 YYDPRINTF ((Perl_debug_log, "Shifting token %s, ", yytname[yytoken]));
456 /* Discard the token being shifted unless it is eof. */
457 if (parser->yychar != YYEOF)
458 parser->yychar = YYEMPTY;
462 ps->val = parser->yylval;
463 ps->comppad = PL_comppad;
465 ps->name = (const char *)(yytname[yytoken]);
468 /* Count tokens shifted since error; after three, turn off error
470 if (parser->yyerrstatus)
471 parser->yyerrstatus--;
476 /*-----------------------------------------------------------.
477 | yydefault -- do the default action for the current state. |
478 `-----------------------------------------------------------*/
480 yyn = yydefact[yystate];
486 /*-----------------------------.
487 | yyreduce -- Do a reduction. |
488 `-----------------------------*/
490 /* yyn is the number of a rule to reduce with. */
491 parser->yylen = yyr2[yyn];
493 /* If YYLEN is nonzero, implement the default value of the action:
496 Otherwise, the following line sets YYVAL to garbage.
497 This behavior is undocumented and Bison
498 users should not rely upon it. Assigning to YYVAL
499 unconditionally makes the parser a bit smaller, and it avoids a
500 GCC warning that YYVAL may be used uninitialized. */
501 yyval = ps[1-parser->yylen].val;
503 YY_STACK_PRINT(parser);
504 YY_REDUCE_PRINT (yyn);
509 #define dep() deprecate("\"do\" to call subroutines")
511 #ifdef PERL_IN_MADLY_C
512 # define IVAL(i) (i)->tk_lval.ival
513 # define PVAL(p) (p)->tk_lval.pval
514 # define TOKEN_GETMAD(a,b,c) token_getmad((a),(b),(c))
515 # define TOKEN_FREE(a) token_free(a)
516 # define OP_GETMAD(a,b,c) op_getmad((a),(b),(c))
517 # define IF_MAD(a,b) (a)
523 # define TOKEN_GETMAD(a,b,c)
524 # define TOKEN_FREE(a)
525 # define OP_GETMAD(a,b,c)
526 # define IF_MAD(a,b) (b)
531 /* contains all the rule actions; auto-generated from perly.y */
536 /* any just-reduced ops with the op_latefreed flag cleared need to be
537 * freed; the rest need the flag resetting */
540 for (i=0; i< parser->yylen; i++) {
541 if (yy_type_tab[yystos[ps[-i].state]] == toketype_opval
544 ps[-i].val.opval->op_latefree = 0;
545 if (ps[-i].val.opval->op_latefreed)
546 op_free(ps[-i].val.opval);
551 parser->ps = ps -= (parser->yylen-1);
553 /* Now shift the result of the reduction. Determine what state
554 that goes to, based on the state we popped back to and the rule
555 number reduced by. */
558 ps->comppad = PL_comppad;
560 ps->name = (const char *)(yytname [yyr1[yyn]]);
565 yystate = yypgoto[yyn - YYNTOKENS] + ps[-1].state;
566 if (0 <= yystate && yystate <= YYLAST && yycheck[yystate] == ps[-1].state)
567 yystate = yytable[yystate];
569 yystate = yydefgoto[yyn - YYNTOKENS];
575 /*------------------------------------.
576 | yyerrlab -- here on detecting error |
577 `------------------------------------*/
579 /* If not already recovering from an error, report this error. */
580 if (!parser->yyerrstatus) {
581 yyerror ("syntax error");
585 if (parser->yyerrstatus == 3) {
586 /* If just tried and failed to reuse lookahead token after an
587 error, discard it. */
589 /* Return failure if at end of input. */
590 if (parser->yychar == YYEOF) {
591 /* Pop the error token. */
593 /* Pop the rest of the stack. */
594 while (ps > parser->stack) {
595 YYDSYMPRINTF ("Error: popping", yystos[ps->state], &ps->val);
596 if (yy_type_tab[yystos[ps->state]] == toketype_opval
599 YYDPRINTF ((Perl_debug_log, "(freeing op)\n"));
600 if (ps->comppad != PL_comppad) {
601 PAD_RESTORE_LOCAL(ps->comppad);
603 ps->val.opval->op_latefree = 0;
604 op_free(ps->val.opval);
611 YYDSYMPRINTF ("Error: discarding", yytoken, &parser->yylval);
612 parser->yychar = YYEMPTY;
616 /* Else will try to reuse lookahead token after shifting the error
621 /*----------------------------------------------------.
622 | yyerrlab1 -- error raised explicitly by an action. |
623 `----------------------------------------------------*/
625 parser->yyerrstatus = 3; /* Each real token shifted decrements this. */
628 yyn = yypact[yystate];
629 if (yyn != YYPACT_NINF) {
631 if (0 <= yyn && yyn <= YYLAST && yycheck[yyn] == YYTERROR) {
638 /* Pop the current state because it cannot handle the error token. */
639 if (ps == parser->stack)
642 YYDSYMPRINTF ("Error: popping", yystos[ps->state], &ps->val);
643 if (yy_type_tab[yystos[ps->state]] == toketype_opval && ps->val.opval) {
644 YYDPRINTF ((Perl_debug_log, "(freeing op)\n"));
645 if (ps->comppad != PL_comppad) {
646 PAD_RESTORE_LOCAL(ps->comppad);
648 ps->val.opval->op_latefree = 0;
649 op_free(ps->val.opval);
654 YY_STACK_PRINT(parser);
660 YYDPRINTF ((Perl_debug_log, "Shifting error token, "));
664 ps->val = parser->yylval;
665 ps->comppad = PL_comppad;
673 /*-------------------------------------.
674 | yyacceptlab -- YYACCEPT comes here. |
675 `-------------------------------------*/
678 parser->ps = parser->stack; /* disable cleanup */
681 /*-----------------------------------.
682 | yyabortlab -- YYABORT comes here. |
683 `-----------------------------------*/
689 LEAVE; /* force parser free before we return */
695 * c-indentation-style: bsd
697 * indent-tabs-mode: t
700 * ex: set ts=8 sts=4 sw=4 noet: