]>
git.saurik.com Git - bison.git/blob - src/output.c
705db814fccafdf6216065b8a9dc8c8db3d63a6b
1 /* Output the generated parsing program for bison,
2 Copyright 1984, 1986, 1989, 1992, 2000, 2001 Free Software Foundation, Inc.
4 This file is part of Bison, the GNU Compiler Compiler.
6 Bison is free software; you can redistribute it and/or modify it
7 under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
11 Bison is distributed in the hope that it will be useful, but
12 WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with Bison; see the file COPYING. If not, write to the Free
18 Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
22 /* The parser tables consist of these tables.
23 Starred ones needed only for the semantic parser.
24 Double starred are output only if switches are set.
26 yytranslate = vector mapping yylex's token numbers into bison's token
29 ** yytname = vector of string-names indexed by bison token number
31 ** yytoknum = vector of yylex token numbers corresponding to entries
34 yyrline = vector of line-numbers of all rules. For yydebug printouts.
36 yyrhs = vector of items of all rules.
37 This is exactly what ritems contains. For yydebug and for semantic
40 yyprhs[r] = index in yyrhs of first item for rule r.
42 yyr1[r] = symbol number of symbol that rule r derives.
44 yyr2[r] = number of symbols composing right hand side of rule r.
46 * yystos[s] = the symbol number of the symbol that leads to state s.
48 yydefact[s] = default rule to reduce with in state s,
49 when yytable doesn't specify something else to do.
50 Zero means the default is an error.
52 yydefgoto[i] = default state to go to after a reduction of a rule that
53 generates variable ntokens + i, except when yytable
54 specifies something else to do.
56 yypact[s] = index in yytable of the portion describing state s.
57 The lookahead token's type is used to index that portion
58 to find out what to do.
60 If the value in yytable is positive,
61 we shift the token and go to that state.
63 If the value is negative, it is minus a rule number to reduce by.
65 If the value is zero, the default action from yydefact[s] is used.
67 yypgoto[i] = the index in yytable of the portion describing
68 what to do after reducing a rule that derives variable i + ntokens.
69 This portion is indexed by the parser state number, s,
70 as of before the text for this nonterminal was read.
71 The value from yytable is the state to go to if
72 the corresponding value in yycheck is s.
74 yytable = a vector filled with portions for different uses,
75 found via yypact and yypgoto.
77 yycheck = a vector indexed in parallel with yytable.
78 It indicates, in a roundabout way, the bounds of the
79 portion you are trying to examine.
81 Suppose that the portion of yytable starts at index p
82 and the index to be examined within the portion is i.
83 Then if yycheck[p+i] != i, i is outside the bounds
84 of what is actually allocated, and the default
85 (from yydefact or yydefgoto) should be used.
86 Otherwise, yytable[p+i] should be used.
88 YYFINAL = the state number of the termination state.
89 YYFLAG = most negative short int. Used to flag ??
103 #include "conflicts.h"
104 #include "muscle_tab.h"
109 static short **froms
= NULL
;
110 static short **tos
= NULL
;
111 static short *tally
= NULL
;
112 static short *width
= NULL
;
113 static short *actrow
= NULL
;
114 static short *state_count
= NULL
;
115 static short *order
= NULL
;
116 static short *base
= NULL
;
117 static short *pos
= NULL
;
118 static short *table
= NULL
;
119 static short *check
= NULL
;
123 struct obstack muscle_obstack
;
124 static struct obstack format_obstack
;
126 int error_verbose
= 0;
128 /* Returns the number of lines of S. */
130 get_lines_number (const char *s
)
135 for (i
= 0; s
[i
]; ++i
)
148 output_table_data (struct obstack
*oout
,
157 obstack_fgrow1 (oout
, "%6d", first
);
158 for (i
= begin
; i
< end
; ++i
)
160 obstack_1grow (oout
, ',');
163 obstack_sgrow (oout
, "\n ");
168 obstack_fgrow1 (oout
, "%6d", table_data
[i
]);
170 obstack_1grow (oout
, 0);
175 output_token_translations (void)
177 output_table_data (&format_obstack
, token_translations
,
178 0, 1, max_user_token_number
+ 1);
179 muscle_insert ("translate", obstack_finish (&format_obstack
));
180 XFREE (token_translations
);
189 short *values
= XCALLOC (short, nrules
+ 1);
190 for (i
= 0; i
< nrules
+ 1; ++i
)
191 values
[i
] = rule_table
[i
].rhs
;
192 output_table_data (&format_obstack
, values
,
197 muscle_insert ("prhs", obstack_finish (&format_obstack
));
200 size_t yyrhs_size
= 1;
204 for (sp
= ritem
+ 1; *sp
; sp
++)
206 yyrhs
= XMALLOC (short, yyrhs_size
);
208 for (sp
= ritem
+ 1, i
= 1; *sp
; ++sp
, ++i
)
209 yyrhs
[i
] = *sp
> 0 ? *sp
: 0;
211 output_table_data (&format_obstack
, yyrhs
,
212 ritem
[0], 1, yyrhs_size
);
213 muscle_insert ("rhs", obstack_finish (&format_obstack
));
219 if (!semantic_parser
)
220 obstack_sgrow (&table_obstack
, "\n#endif\n");
229 short *values
= (short *) alloca (sizeof (short) * nstates
);
230 for (i
= 0; i
< nstates
; ++i
)
231 values
[i
] = state_table
[i
]->accessing_symbol
;
232 output_table_data (&format_obstack
, values
,
234 muscle_insert ("stos", obstack_finish (&format_obstack
));
239 output_rule_data (void)
243 short *short_tab
= NULL
;
246 short *values
= XCALLOC (short, nrules
+ 1);
247 for (i
= 0; i
< nrules
+ 1; ++i
)
248 values
[i
] = rule_table
[i
].line
;
249 output_table_data (&format_obstack
, values
,
251 muscle_insert ("rline", obstack_finish (&format_obstack
));
257 for (i
= 0; i
< nsyms
; i
++)
259 /* Be sure not to use twice the same quotearg slot. */
261 quotearg_n_style (1, c_quoting_style
,
262 quotearg_style (escape_quoting_style
, tags
[i
]));
263 /* Width of the next token, including the two quotes, the coma
265 int strsize
= strlen (cp
) + 2;
267 if (j
+ strsize
> 75)
269 obstack_sgrow (&format_obstack
, "\n ");
273 obstack_sgrow (&format_obstack
, cp
);
274 obstack_sgrow (&format_obstack
, ", ");
277 /* add a NULL entry to list of tokens */
278 obstack_sgrow (&format_obstack
, "NULL");
280 /* Finish table and store. */
281 obstack_1grow (&format_obstack
, 0);
282 muscle_insert ("tname", obstack_finish (&format_obstack
));
284 /* Output YYTOKNUM. */
285 output_table_data (&format_obstack
, user_toknums
,
287 muscle_insert ("toknum", obstack_finish (&format_obstack
));
291 short *values
= XCALLOC (short, nrules
+ 1);
292 for (i
= 0; i
< nrules
+ 1; ++i
)
293 values
[i
] = rule_table
[i
].lhs
;
294 output_table_data (&format_obstack
, values
,
296 muscle_insert ("r1", obstack_finish (&format_obstack
));
301 short_tab
= XMALLOC (short, nrules
+ 1);
302 for (i
= 1; i
< nrules
; i
++)
303 short_tab
[i
] = rule_table
[i
+ 1].rhs
- rule_table
[i
].rhs
- 1;
304 short_tab
[nrules
] = nitems
- rule_table
[nrules
].rhs
- 1;
305 output_table_data (&format_obstack
, short_tab
,
307 muscle_insert ("r2", obstack_finish (&format_obstack
));
311 /*------------------------------------------------------------------.
312 | Decide what to do for each type of token if seen as the lookahead |
313 | token in specified state. The value returned is used as the |
314 | default action (yydefact) for the state. In addition, actrow is |
315 | filled with what to do for each kind of token, index by symbol |
316 | number, with zero meaning do the default action. The value |
317 | MINSHORT, a very negative number, means this situation is an |
318 | error. The parser recognizes this value specially. |
320 | This is where conflicts are resolved. The loop over lookahead |
321 | rules considered lower-numbered rules last, and the last rule |
322 | considered that likes a token gets to handle it. |
323 `------------------------------------------------------------------*/
326 action_row (state_t
*state
)
329 int default_rule
= 0;
330 reductions
*redp
= state
->reductions
;
331 int nreds
= redp
? redp
->nreds
: 0;
332 shifts
*shiftp
= state
->shifts
;
333 errs
*errp
= state
->errs
;
334 /* set nonzero to inhibit having any default reduction */
337 for (i
= 0; i
< ntokens
; i
++)
343 /* loop over all the rules available here which require
345 for (i
= state
->nlookaheads
- 1; i
>= 0; --i
)
346 /* and find each token which the rule finds acceptable
348 for (j
= 0; j
< ntokens
; j
++)
349 /* and record this rule as the rule to use if that
351 if (BITISSET (LA (state
->lookaheadsp
+ i
), j
))
352 actrow
[j
] = -LAruleno
[state
->lookaheadsp
+ i
];
355 /* Now see which tokens are allowed for shifts in this state. For
356 them, record the shift as the thing to do. So shift is preferred
358 for (i
= 0; i
< shiftp
->nshifts
; i
++)
361 int shift_state
= shiftp
->shifts
[i
];
365 symbol
= state_table
[shift_state
]->accessing_symbol
;
370 actrow
[symbol
] = shift_state
;
372 /* Do not use any default reduction if there is a shift for
374 if (symbol
== error_token_number
)
378 /* See which tokens are an explicit error in this state (due to
379 %nonassoc). For them, record MINSHORT as the action. */
381 for (i
= 0; i
< errp
->nerrs
; i
++)
383 int symbol
= errp
->errs
[i
];
384 actrow
[symbol
] = MINSHORT
;
387 /* Now find the most common reduction and make it the default action
390 if (nreds
>= 1 && !nodefault
)
392 if (state
->consistent
)
393 default_rule
= redp
->rules
[0];
397 for (i
= 0; i
< state
->nlookaheads
; i
++)
400 int rule
= -LAruleno
[state
->lookaheadsp
+ i
];
403 for (j
= 0; j
< ntokens
; j
++)
404 if (actrow
[j
] == rule
)
414 /* actions which match the default are replaced with zero,
415 which means "use the default" */
420 for (j
= 0; j
< ntokens
; j
++)
421 if (actrow
[j
] == default_rule
)
424 default_rule
= -default_rule
;
429 /* If have no default rule, the default is an error.
430 So replace any action which says "error" with "use default". */
432 if (default_rule
== 0)
433 for (i
= 0; i
< ntokens
; i
++)
434 if (actrow
[i
] == MINSHORT
)
451 for (i
= 0; i
< ntokens
; i
++)
458 froms
[state
] = sp1
= sp
= XCALLOC (short, count
);
459 tos
[state
] = sp2
= XCALLOC (short, count
);
461 for (i
= 0; i
< ntokens
; i
++)
468 tally
[state
] = count
;
469 width
[state
] = sp1
[-1] - sp
[0] + 1;
473 /*------------------------------------------------------------------.
474 | Figure out the actions for the specified state, indexed by |
475 | lookahead token type. |
477 | The YYDEFACT table is output now. The detailed info is saved for |
478 | putting into YYTABLE later. |
479 `------------------------------------------------------------------*/
485 short *yydefact
= XCALLOC (short, nstates
);
487 actrow
= XCALLOC (short, ntokens
);
488 for (i
= 0; i
< nstates
; ++i
)
490 yydefact
[i
] = action_row (state_table
[i
]);
494 output_table_data (&format_obstack
, yydefact
,
495 yydefact
[0], 1, nstates
);
496 muscle_insert ("defact", obstack_finish (&format_obstack
));
503 /*-----------------------------.
504 | Output the actions to OOUT. |
505 `-----------------------------*/
508 actions_output (FILE *out
, size_t *line
)
511 for (rule
= 1; rule
< nrules
+ 1; ++rule
)
512 if (rule_table
[rule
].action
)
514 fprintf (out
, " case %d:\n", rule
);
517 fprintf (out
, muscle_find ("linef"),
518 rule_table
[rule
].action_line
,
519 quotearg_style (c_quoting_style
,
520 muscle_find ("filename")));
521 /* As a Bison extension, add the ending semicolon. Since some
522 Yacc don't do that, help people using bison as a Yacc
523 finding their missing semicolons. */
524 fprintf (out
, "{ %s%s }\n break;\n\n",
525 rule_table
[rule
].action
,
526 yacc_flag
? ";" : "");
528 /* We always output 4 '\n' per action. */
530 /* Plus one if !no_lines_flag. */
533 /* Get the number of lines written by the user. */
534 *line
+= get_lines_number (rule_table
[rule
].action
);
540 save_column (int symbol
, int default_state
)
547 int symno
= symbol
- ntokens
+ nstates
;
549 short begin
= goto_map
[symbol
];
550 short end
= goto_map
[symbol
+ 1];
553 for (i
= begin
; i
< end
; i
++)
554 if (to_state
[i
] != default_state
)
560 froms
[symno
] = sp1
= sp
= XCALLOC (short, count
);
561 tos
[symno
] = sp2
= XCALLOC (short, count
);
563 for (i
= begin
; i
< end
; i
++)
564 if (to_state
[i
] != default_state
)
566 *sp1
++ = from_state
[i
];
567 *sp2
++ = to_state
[i
];
570 tally
[symno
] = count
;
571 width
[symno
] = sp1
[-1] - sp
[0] + 1;
575 default_goto (int symbol
)
578 int m
= goto_map
[symbol
];
579 int n
= goto_map
[symbol
+ 1];
580 int default_state
= -1;
586 for (i
= 0; i
< nstates
; i
++)
589 for (i
= m
; i
< n
; i
++)
590 state_count
[to_state
[i
]]++;
592 for (i
= 0; i
< nstates
; i
++)
593 if (state_count
[i
] > max
)
595 max
= state_count
[i
];
599 return default_state
;
603 /*-------------------------------------------------------------------.
604 | Figure out what to do after reducing with each rule, depending on |
605 | the saved state from before the beginning of parsing the data that |
606 | matched this rule. |
608 | The YYDEFGOTO table is output now. The detailed info is saved for |
609 | putting into YYTABLE later. |
610 `-------------------------------------------------------------------*/
616 short *yydefgoto
= XMALLOC (short, nsyms
- ntokens
);
618 state_count
= XCALLOC (short, nstates
);
619 for (i
= ntokens
; i
< nsyms
; ++i
)
621 int default_state
= default_goto (i
);
622 save_column (i
, default_state
);
623 yydefgoto
[i
- ntokens
] = default_state
;
626 output_table_data (&format_obstack
, yydefgoto
,
627 yydefgoto
[0], 1, nsyms
- ntokens
);
628 muscle_insert ("defgoto", obstack_finish (&format_obstack
));
635 /* The next few functions decide how to pack the actions and gotos
636 information into yytable. */
643 order
= XCALLOC (short, nvectors
);
646 for (i
= 0; i
< nvectors
; i
++)
652 int j
= nentries
- 1;
654 while (j
>= 0 && (width
[order
[j
]] < w
))
657 while (j
>= 0 && (width
[order
[j
]] == w
) && (tally
[order
[j
]] < t
))
660 for (k
= nentries
- 1; k
> j
; k
--)
661 order
[k
+ 1] = order
[k
];
670 matching_state (int vector
)
672 int i
= order
[vector
];
683 for (prev
= vector
- 1; prev
>= 0; prev
--)
689 if (width
[j
] != w
|| tally
[j
] != t
)
692 for (k
= 0; match
&& k
< t
; k
++)
693 if (tos
[j
][k
] != tos
[i
][k
] || froms
[j
][k
] != froms
[i
][k
])
705 pack_vector (int vector
)
707 int i
= order
[vector
];
711 short *from
= froms
[i
];
716 for (j
= lowzero
- from
[0]; j
< MAXTABLE
; j
++)
721 for (k
= 0; ok
&& k
< t
; k
++)
725 fatal (_("maximum table size (%d) exceeded"), MAXTABLE
);
731 for (k
= 0; ok
&& k
< vector
; k
++)
737 for (k
= 0; k
< t
; k
++)
741 check
[loc
] = from
[k
];
744 while (table
[lowzero
] != 0)
753 #define pack_vector_succeeded 0
754 assert (pack_vector_succeeded
);
766 base
= XCALLOC (short, nvectors
);
767 pos
= XCALLOC (short, nentries
);
768 table
= XCALLOC (short, MAXTABLE
);
769 check
= XCALLOC (short, MAXTABLE
);
774 for (i
= 0; i
< nvectors
; i
++)
777 for (i
= 0; i
< MAXTABLE
; i
++)
780 for (i
= 0; i
< nentries
; i
++)
782 state
= matching_state (i
);
785 place
= pack_vector (i
);
790 base
[order
[i
]] = place
;
793 for (i
= 0; i
< nvectors
; i
++)
804 /* the following functions output yytable, yycheck
805 and the vectors whose elements index the portion starts */
811 output_table_data (&format_obstack
, base
,
812 base
[0], 1, nstates
);
813 muscle_insert ("pact", obstack_finish (&format_obstack
));
816 output_table_data (&format_obstack
, base
,
817 base
[nstates
], nstates
+ 1, nvectors
);
818 muscle_insert ("pgoto", obstack_finish (&format_obstack
));
827 output_table_data (&format_obstack
, table
,
828 table
[0], 1, high
+ 1);
829 muscle_insert ("table", obstack_finish (&format_obstack
));
837 output_table_data (&format_obstack
, check
,
838 check
[0], 1, high
+ 1);
839 muscle_insert ("check", obstack_finish (&format_obstack
));
843 /* compute and output yydefact, yydefgoto, yypact, yypgoto, yytable
847 output_actions (void)
850 nvectors
= nstates
+ nvars
;
852 froms
= XCALLOC (short *, nvectors
);
853 tos
= XCALLOC (short *, nvectors
);
854 tally
= XCALLOC (short, nvectors
);
855 width
= XCALLOC (short, nvectors
);
862 XFREE (goto_map
+ ntokens
);
874 for (i
= 0; i
< nstates
; ++i
)
876 XFREE (state_table
[i
]->shifts
);
877 XFREE (state_table
[i
]->reductions
);
878 XFREE (state_table
[i
]->errs
);
879 free (state_table
[i
]);
885 /*------------------------------------------------------------.
886 | Copy the parser code from SKEL_FILENAME into OOUT obstack. |
887 | and do the muscle substitution. |
888 `------------------------------------------------------------*/
891 output_parser (const char *skel_filename
, FILE *out
)
896 size_t skeleton_line
;
898 fskel
= xfopen (skel_filename
, "r");
900 /* New output code. */
916 else if ((c
= getc (fskel
)) == '%')
918 /* Read the muscle. */
919 const char *muscle_key
= 0;
920 const char *muscle_value
= 0;
922 while (isalnum (c
= getc (fskel
)) || c
== '-')
923 obstack_1grow (&muscle_obstack
, c
);
924 obstack_1grow (&muscle_obstack
, 0);
926 /* Output the right value, or see if it's something special. */
927 muscle_key
= obstack_finish (&muscle_obstack
);
928 muscle_value
= muscle_find (muscle_key
);
929 if (!strcmp (muscle_key
, "actions"))
930 actions_output (out
, &output_line
);
931 else if (!strcmp (muscle_key
, "line"))
932 fprintf (out
, "%d", output_line
);
933 else if (!strcmp (muscle_key
, "skeleton-line"))
934 fprintf (out
, "%d", skeleton_line
);
935 else if (muscle_value
)
937 fputs (muscle_value
, out
);
938 output_line
+= get_lines_number (muscle_value
);
943 fputs (muscle_key
, out
);
954 /*----------------------------------------.
955 | Prepare the master parser to be output |
956 `----------------------------------------*/
959 output_master_parser (void)
961 FILE *parser
= xfopen (parser_file_name
, "w");
965 skeleton
= skeleton_find ("BISON_HAIRY", BISON_HAIRY
);
967 skeleton
= skeleton_find ("BISON_SIMPLE", BISON_SIMPLE
);
969 muscle_insert ("skeleton", skeleton
);
970 muscle_insert ("parser-file-name", parser_file_name
);
972 output_parser (skeleton
, parser
);
979 #define MUSCLE_INSERT_INT(Key, Value) \
981 obstack_fgrow1 (&muscle_obstack, "%d", Value); \
982 obstack_1grow (&muscle_obstack, 0); \
983 muscle_insert (Key, obstack_finish (&muscle_obstack)); \
986 #define MUSCLE_INSERT_STRING(Key, Value) \
988 obstack_sgrow (&muscle_obstack, Value); \
989 obstack_1grow (&muscle_obstack, 0); \
990 muscle_insert (Key, obstack_finish (&muscle_obstack)); \
993 #define MUSCLE_INSERT_PREFIX(Key, Value) \
995 obstack_fgrow2 (&muscle_obstack, "%s%s", spec_name_prefix, Value); \
996 obstack_1grow (&muscle_obstack, 0); \
997 muscle_insert (Key, obstack_finish (&muscle_obstack)); \
1003 MUSCLE_INSERT_INT ("last", high
);
1004 MUSCLE_INSERT_INT ("flag", MINSHORT
);
1005 MUSCLE_INSERT_INT ("pure", pure_parser
);
1006 MUSCLE_INSERT_INT ("nsym", nsyms
);
1007 MUSCLE_INSERT_INT ("debug", debug_flag
);
1008 MUSCLE_INSERT_INT ("final", final_state
);
1009 MUSCLE_INSERT_INT ("maxtok", max_user_token_number
);
1010 MUSCLE_INSERT_INT ("error-verbose", error_verbose
);
1011 MUSCLE_INSERT_STRING ("prefix", spec_name_prefix
);
1013 MUSCLE_INSERT_INT ("nnts", nvars
);
1014 MUSCLE_INSERT_INT ("nrules", nrules
);
1015 MUSCLE_INSERT_INT ("nstates", nstates
);
1016 MUSCLE_INSERT_INT ("ntokens", ntokens
);
1018 MUSCLE_INSERT_INT ("locations-flag", locations_flag
);
1022 /*-------------------------.
1023 | Output the header file. |
1024 `-------------------------*/
1027 header_output (void)
1029 FILE *out
= xfopen (spec_defines_file
, "w");
1030 char *macro_name
= compute_header_macro ();
1032 fprintf (out
, "#ifndef %s\n", macro_name
);
1033 fprintf (out
, "# define %s\n\n", macro_name
);
1035 fputs (muscle_find ("tokendef"), out
);
1040 # define YYSTYPE yystype\n\
1042 muscle_find ("stype"));
1045 fprintf (out
, "\nextern YYSTYPE %slval;\n",
1047 if (semantic_parser
)
1051 for (i
= ntokens
; i
< nsyms
; i
++)
1052 /* don't make these for dummy nonterminals made by gensym. */
1053 if (*tags
[i
] != '@')
1054 fprintf (out
, "# define NT%s\t%d\n", tags
[i
], i
);
1057 fprintf (out
, "\n#endif /* not %s */\n", macro_name
);
1063 /*----------------------------------------------------------.
1064 | Output the parsing tables and the parser code to ftable. |
1065 `----------------------------------------------------------*/
1070 obstack_init (&format_obstack
);
1072 output_token_translations ();
1076 if (semantic_parser
)
1078 output_rule_data ();
1079 XFREE (user_toknums
);
1083 /* Copy definitions in directive. */
1084 obstack_1grow (&attrs_obstack
, 0);
1085 muscle_insert ("prologue", obstack_finish (&attrs_obstack
));
1087 /* Output the parser. */
1088 output_master_parser ();
1089 /* Output the header if needed. */
1093 free (rule_table
+ 1);
1094 obstack_free (&muscle_obstack
, 0);
1095 obstack_free (&format_obstack
, 0);
1096 obstack_free (&action_obstack
, 0);