]>
git.saurik.com Git - bison.git/blob - src/output.c
4de58e9e1870d8bc84f64a0cd05f8d594cbe6316
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 struct obstack output_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 (&output_obstack
, token_translations
,
178 0, 1, max_user_token_number
+ 1);
179 muscle_insert ("translate", obstack_finish (&output_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 (&output_obstack
, values
,
197 muscle_insert ("prhs", obstack_finish (&output_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 (&output_obstack
, yyrhs
,
212 ritem
[0], 1, yyrhs_size
);
213 muscle_insert ("rhs", obstack_finish (&output_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 (&output_obstack
, values
,
234 muscle_insert ("stos", obstack_finish (&output_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 (&output_obstack
, values
,
251 muscle_insert ("rline", obstack_finish (&output_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 (&output_obstack
, "\n ");
273 obstack_sgrow (&output_obstack
, cp
);
274 obstack_sgrow (&output_obstack
, ", ");
277 /* add a NULL entry to list of tokens */
278 obstack_sgrow (&output_obstack
, "NULL");
280 /* Finish table and store. */
281 obstack_1grow (&output_obstack
, 0);
282 muscle_insert ("tname", obstack_finish (&output_obstack
));
284 /* Output YYTOKNUM. */
285 output_table_data (&output_obstack
, user_toknums
,
287 muscle_insert ("toknum", obstack_finish (&output_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 (&output_obstack
, values
,
296 muscle_insert ("r1", obstack_finish (&output_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 (&output_obstack
, short_tab
,
307 muscle_insert ("r2", obstack_finish (&output_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 (int state
)
341 int nodefault
= 0; /* set nonzero to inhibit having any default reduction */
343 for (i
= 0; i
< ntokens
; i
++)
348 redp
= state_table
[state
]->reductions
;
356 /* loop over all the rules available here which require
358 m
= state_table
[state
]->lookaheads
;
359 n
= state_table
[state
+ 1]->lookaheads
;
361 for (i
= n
- 1; i
>= m
; i
--)
362 /* and find each token which the rule finds acceptable
364 for (j
= 0; j
< ntokens
; j
++)
365 /* and record this rule as the rule to use if that
367 if (BITISSET (LA (i
), j
))
368 actrow
[j
] = -LAruleno
[i
];
372 /* Now see which tokens are allowed for shifts in this state. For
373 them, record the shift as the thing to do. So shift is preferred
375 shiftp
= state_table
[state
]->shifts
;
376 for (i
= 0; i
< shiftp
->nshifts
; i
++)
378 shift_state
= shiftp
->shifts
[i
];
382 symbol
= state_table
[shift_state
]->accessing_symbol
;
387 actrow
[symbol
] = shift_state
;
389 /* Do not use any default reduction if there is a shift for
391 if (symbol
== error_token_number
)
395 /* See which tokens are an explicit error in this state (due to
396 %nonassoc). For them, record MINSHORT as the action. */
397 errp
= state_table
[state
]->errs
;
403 for (i
= 0; i
< k
; i
++)
405 symbol
= errp
->errs
[i
];
406 actrow
[symbol
] = MINSHORT
;
410 /* Now find the most common reduction and make it the default action
413 if (nreds
>= 1 && !nodefault
)
415 if (state_table
[state
]->consistent
)
416 default_rule
= redp
->rules
[0];
420 for (i
= m
; i
< n
; i
++)
425 for (j
= 0; j
< ntokens
; j
++)
427 if (actrow
[j
] == rule
)
438 /* actions which match the default are replaced with zero,
439 which means "use the default" */
443 for (j
= 0; j
< ntokens
; j
++)
445 if (actrow
[j
] == default_rule
)
449 default_rule
= -default_rule
;
454 /* If have no default rule, the default is an error.
455 So replace any action which says "error" with "use default". */
457 if (default_rule
== 0)
458 for (j
= 0; j
< ntokens
; j
++)
460 if (actrow
[j
] == MINSHORT
)
478 for (i
= 0; i
< ntokens
; i
++)
487 froms
[state
] = sp1
= sp
= XCALLOC (short, count
);
488 tos
[state
] = sp2
= XCALLOC (short, count
);
490 for (i
= 0; i
< ntokens
; i
++)
499 tally
[state
] = count
;
500 width
[state
] = sp1
[-1] - sp
[0] + 1;
504 /*------------------------------------------------------------------.
505 | Figure out the actions for the specified state, indexed by |
506 | lookahead token type. |
508 | The YYDEFACT table is output now. The detailed info is saved for |
509 | putting into YYTABLE later. |
510 `------------------------------------------------------------------*/
516 short *yydefact
= XCALLOC (short, nstates
);
518 actrow
= XCALLOC (short, ntokens
);
519 for (i
= 0; i
< nstates
; ++i
)
521 yydefact
[i
] = action_row (i
);
525 output_table_data (&output_obstack
, yydefact
,
526 yydefact
[0], 1, nstates
);
527 muscle_insert ("defact", obstack_finish (&output_obstack
));
534 /*-----------------------------.
535 | Output the actions to OOUT. |
536 `-----------------------------*/
539 actions_output (FILE *out
, size_t *line
)
542 for (rule
= 1; rule
< nrules
+ 1; ++rule
)
543 if (rule_table
[rule
].action
)
545 fprintf (out
, " case %d:\n", rule
);
548 fprintf (out
, muscle_find ("linef"),
549 rule_table
[rule
].action_line
,
550 quotearg_style (c_quoting_style
,
551 muscle_find ("filename")));
552 /* As a Bison extension, add the ending semicolon. Since some
553 Yacc don't do that, help people using bison as a Yacc
554 finding their missing semicolons. */
555 fprintf (out
, "{ %s%s }\n break;\n\n",
556 rule_table
[rule
].action
,
557 yacc_flag
? ";" : "");
559 /* We always output 5 '\n' per action. */
561 /* Get the number of lines written by the user. */
562 *line
+= get_lines_number (rule_table
[rule
].action
);
568 save_column (int symbol
, int default_state
)
577 short begin
= goto_map
[symbol
];
578 short end
= goto_map
[symbol
+ 1];
581 for (i
= begin
; i
< end
; i
++)
583 if (to_state
[i
] != default_state
)
590 symno
= symbol
- ntokens
+ nstates
;
592 froms
[symno
] = sp1
= sp
= XCALLOC (short, count
);
593 tos
[symno
] = sp2
= XCALLOC (short, count
);
595 for (i
= begin
; i
< end
; i
++)
597 if (to_state
[i
] != default_state
)
599 *sp1
++ = from_state
[i
];
600 *sp2
++ = to_state
[i
];
604 tally
[symno
] = count
;
605 width
[symno
] = sp1
[-1] - sp
[0] + 1;
609 default_goto (int symbol
)
617 m
= goto_map
[symbol
];
618 n
= goto_map
[symbol
+ 1];
623 for (i
= 0; i
< nstates
; i
++)
626 for (i
= m
; i
< n
; i
++)
627 state_count
[to_state
[i
]]++;
632 for (i
= 0; i
< nstates
; i
++)
634 if (state_count
[i
] > max
)
636 max
= state_count
[i
];
641 return default_state
;
645 /*-------------------------------------------------------------------.
646 | Figure out what to do after reducing with each rule, depending on |
647 | the saved state from before the beginning of parsing the data that |
648 | matched this rule. |
650 | The YYDEFGOTO table is output now. The detailed info is saved for |
651 | putting into YYTABLE later. |
652 `-------------------------------------------------------------------*/
658 short *yydefgoto
= XMALLOC (short, nsyms
- ntokens
);
660 state_count
= XCALLOC (short, nstates
);
661 for (i
= ntokens
; i
< nsyms
; ++i
)
663 int default_state
= default_goto (i
);
664 save_column (i
, default_state
);
665 yydefgoto
[i
- ntokens
] = default_state
;
668 output_table_data (&output_obstack
, yydefgoto
,
669 yydefgoto
[0], 1, nsyms
- ntokens
);
670 muscle_insert ("defgoto", obstack_finish (&output_obstack
));
677 /* The next few functions decide how to pack the actions and gotos
678 information into yytable. */
689 order
= XCALLOC (short, nvectors
);
692 for (i
= 0; i
< nvectors
; i
++)
700 while (j
>= 0 && (width
[order
[j
]] < w
))
703 while (j
>= 0 && (width
[order
[j
]] == w
) && (tally
[order
[j
]] < t
))
706 for (k
= nentries
- 1; k
> j
; k
--)
707 order
[k
+ 1] = order
[k
];
717 matching_state (int vector
)
734 for (prev
= vector
- 1; prev
>= 0; prev
--)
737 if (width
[j
] != w
|| tally
[j
] != t
)
741 for (k
= 0; match
&& k
< t
; k
++)
743 if (tos
[j
][k
] != tos
[i
][k
] || froms
[j
][k
] != froms
[i
][k
])
756 pack_vector (int vector
)
775 for (j
= lowzero
- from
[0]; j
< MAXTABLE
; j
++)
779 for (k
= 0; ok
&& k
< t
; k
++)
783 fatal (_("maximum table size (%d) exceeded"), MAXTABLE
);
789 for (k
= 0; ok
&& k
< vector
; k
++)
797 for (k
= 0; k
< t
; k
++)
801 check
[loc
] = from
[k
];
804 while (table
[lowzero
] != 0)
814 assert (!"pack_vector");
826 base
= XCALLOC (short, nvectors
);
827 pos
= XCALLOC (short, nentries
);
828 table
= XCALLOC (short, MAXTABLE
);
829 check
= XCALLOC (short, MAXTABLE
);
834 for (i
= 0; i
< nvectors
; i
++)
837 for (i
= 0; i
< MAXTABLE
; i
++)
840 for (i
= 0; i
< nentries
; i
++)
842 state
= matching_state (i
);
845 place
= pack_vector (i
);
850 base
[order
[i
]] = place
;
853 for (i
= 0; i
< nvectors
; i
++)
866 /* the following functions output yytable, yycheck
867 and the vectors whose elements index the portion starts */
873 output_table_data (&output_obstack
, base
,
874 base
[0], 1, nstates
);
875 muscle_insert ("pact", obstack_finish (&output_obstack
));
878 output_table_data (&output_obstack
, base
,
879 base
[nstates
], nstates
+ 1, nvectors
);
880 muscle_insert ("pgoto", obstack_finish (&output_obstack
));
889 output_table_data (&output_obstack
, table
,
890 table
[0], 1, high
+ 1);
891 muscle_insert ("table", obstack_finish (&output_obstack
));
899 output_table_data (&output_obstack
, check
,
900 check
[0], 1, high
+ 1);
901 muscle_insert ("check", obstack_finish (&output_obstack
));
905 /* compute and output yydefact, yydefgoto, yypact, yypgoto, yytable
909 output_actions (void)
912 nvectors
= nstates
+ nvars
;
914 froms
= XCALLOC (short *, nvectors
);
915 tos
= XCALLOC (short *, nvectors
);
916 tally
= XCALLOC (short, nvectors
);
917 width
= XCALLOC (short, nvectors
);
924 XFREE (goto_map
+ ntokens
);
936 for (i
= 0; i
< nstates
; ++i
)
938 XFREE (state_table
[i
]->shifts
);
939 XFREE (state_table
[i
]->reductions
);
940 XFREE (state_table
[i
]->errs
);
941 free (state_table
[i
]);
947 /*------------------------------------------------------------.
948 | Copy the parser code from SKEL_FILENAME into OOUT obstack. |
949 | and do the muscle substitution. |
950 `------------------------------------------------------------*/
953 output_parser (const char *skel_filename
, FILE *out
)
959 fskel
= xfopen (skel_filename
, "r");
961 /* New output code. */
973 else if ((c
= getc (fskel
)) == '%')
975 /* Read the muscle. */
976 const char *muscle_key
= 0;
977 const char *muscle_value
= 0;
979 while (isalnum (c
= getc (fskel
)) || c
== '-')
980 obstack_1grow (&muscle_obstack
, c
);
981 obstack_1grow (&muscle_obstack
, 0);
983 /* Output the right value, or see if it's something special. */
984 muscle_key
= obstack_finish (&muscle_obstack
);
985 muscle_value
= muscle_find (muscle_key
);
986 if (!strcmp (muscle_key
, "actions"))
987 actions_output (out
, &line
);
988 else if (!strcmp (muscle_key
, "line"))
989 fprintf (out
, "%d", line
);
990 else if (muscle_value
)
992 fputs (muscle_value
, out
);
993 line
+= get_lines_number (muscle_value
);
998 fputs (muscle_key
, out
);
1009 /*----------------------------------------.
1010 | Prepare the master parser to be output |
1011 `----------------------------------------*/
1014 output_master_parser (void)
1016 FILE *parser
= xfopen (parser_file_name
, "w");
1019 if (semantic_parser
)
1020 skeleton
= skeleton_find ("BISON_HAIRY", BISON_HAIRY
);
1022 skeleton
= skeleton_find ("BISON_SIMPLE", BISON_SIMPLE
);
1024 muscle_insert ("skeleton", skeleton
);
1025 muscle_insert ("parser-file-name", parser_file_name
);
1027 output_parser (skeleton
, parser
);
1034 #define MUSCLE_INSERT_INT(Key, Value) \
1036 obstack_fgrow1 (&muscle_obstack, "%d", Value); \
1037 obstack_1grow (&muscle_obstack, 0); \
1038 muscle_insert (Key, obstack_finish (&muscle_obstack)); \
1041 #define MUSCLE_INSERT_STRING(Key, Value) \
1043 obstack_sgrow (&muscle_obstack, Value); \
1044 obstack_1grow (&muscle_obstack, 0); \
1045 muscle_insert (Key, obstack_finish (&muscle_obstack)); \
1048 #define MUSCLE_INSERT_PREFIX(Key, Value) \
1050 obstack_fgrow2 (&muscle_obstack, "%s%s", spec_name_prefix, Value); \
1051 obstack_1grow (&muscle_obstack, 0); \
1052 muscle_insert (Key, obstack_finish (&muscle_obstack)); \
1058 MUSCLE_INSERT_INT ("last", high
);
1059 MUSCLE_INSERT_INT ("flag", MINSHORT
);
1060 MUSCLE_INSERT_INT ("pure", pure_parser
);
1061 MUSCLE_INSERT_INT ("nsym", nsyms
);
1062 MUSCLE_INSERT_INT ("debug", debug_flag
);
1063 MUSCLE_INSERT_INT ("final", final_state
);
1064 MUSCLE_INSERT_INT ("maxtok", max_user_token_number
);
1065 MUSCLE_INSERT_INT ("ntbase", ntokens
);
1066 MUSCLE_INSERT_INT ("error-verbose", error_verbose
);
1067 MUSCLE_INSERT_STRING ("prefix", spec_name_prefix
);
1069 MUSCLE_INSERT_INT ("nnts", nvars
);
1070 MUSCLE_INSERT_INT ("nrules", nrules
);
1071 MUSCLE_INSERT_INT ("nstates", nstates
);
1072 MUSCLE_INSERT_INT ("ntokens", ntokens
);
1074 MUSCLE_INSERT_INT ("locations-flag", locations_flag
);
1078 /*-------------------------.
1079 | Output the header file. |
1080 `-------------------------*/
1083 header_output (void)
1085 FILE *out
= xfopen (spec_defines_file
, "w");
1086 char *macro_name
= compute_header_macro ();
1088 fprintf (out
, "#ifndef %s\n", macro_name
);
1089 fprintf (out
, "# define %s\n\n", macro_name
);
1091 fputs (muscle_find ("tokendef"), out
);
1096 # define YYSTYPE yystype\n\
1098 muscle_find ("stype"));
1101 fprintf (out
, "\nextern YYSTYPE %slval;\n",
1103 if (semantic_parser
)
1107 for (i
= ntokens
; i
< nsyms
; i
++)
1108 /* don't make these for dummy nonterminals made by gensym. */
1109 if (*tags
[i
] != '@')
1110 fprintf (out
, "# define\tNT%s\t%d\n", tags
[i
], i
);
1113 fprintf (out
, "\n#endif /* not %s */\n", macro_name
);
1119 /*----------------------------------------------------------.
1120 | Output the parsing tables and the parser code to ftable. |
1121 `----------------------------------------------------------*/
1126 obstack_init (&output_obstack
);
1128 output_token_translations ();
1132 if (semantic_parser
)
1134 output_rule_data ();
1135 XFREE (user_toknums
);
1139 /* Copy definitions in directive. */
1140 obstack_1grow (&attrs_obstack
, 0);
1141 muscle_insert ("prologue", obstack_finish (&attrs_obstack
));
1143 /* Output the parser. */
1144 output_master_parser ();
1145 /* Output the header if needed. */
1149 free (rule_table
+ 1);
1150 obstack_free (&muscle_obstack
, 0);
1151 obstack_free (&output_obstack
, 0);
1152 obstack_free (&action_obstack
, 0);