]>
git.saurik.com Git - bison.git/blob - src/output.c
34560bb5eeced167215f719e16833a72b612cbbe
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
)
340 int nodefault
= 0; /* set nonzero to inhibit having any default reduction */
342 for (i
= 0; i
< ntokens
; i
++)
347 redp
= state_table
[state
]->reductions
;
355 /* loop over all the rules available here which require
357 m
= state_table
[state
]->lookaheads
;
358 n
= state_table
[state
+ 1]->lookaheads
;
360 for (i
= n
- 1; i
>= m
; i
--)
361 /* and find each token which the rule finds acceptable
363 for (j
= 0; j
< ntokens
; j
++)
364 /* and record this rule as the rule to use if that
366 if (BITISSET (LA (i
), j
))
367 actrow
[j
] = -LAruleno
[i
];
371 /* Now see which tokens are allowed for shifts in this state. For
372 them, record the shift as the thing to do. So shift is preferred
374 shiftp
= state_table
[state
]->shifts
;
375 for (i
= 0; i
< shiftp
->nshifts
; i
++)
377 shift_state
= shiftp
->shifts
[i
];
381 symbol
= state_table
[shift_state
]->accessing_symbol
;
386 actrow
[symbol
] = shift_state
;
388 /* Do not use any default reduction if there is a shift for
390 if (symbol
== error_token_number
)
394 /* See which tokens are an explicit error in this state (due to
395 %nonassoc). For them, record MINSHORT as the action. */
396 errp
= state_table
[state
]->errs
;
399 for (i
= 0; i
< errp
->nerrs
; i
++)
401 symbol
= errp
->errs
[i
];
402 actrow
[symbol
] = MINSHORT
;
405 /* Now find the most common reduction and make it the default action
408 if (nreds
>= 1 && !nodefault
)
410 if (state_table
[state
]->consistent
)
411 default_rule
= redp
->rules
[0];
415 for (i
= m
; i
< n
; i
++)
420 for (j
= 0; j
< ntokens
; j
++)
422 if (actrow
[j
] == rule
)
433 /* actions which match the default are replaced with zero,
434 which means "use the default" */
438 for (j
= 0; j
< ntokens
; j
++)
440 if (actrow
[j
] == default_rule
)
444 default_rule
= -default_rule
;
449 /* If have no default rule, the default is an error.
450 So replace any action which says "error" with "use default". */
452 if (default_rule
== 0)
453 for (j
= 0; j
< ntokens
; j
++)
455 if (actrow
[j
] == MINSHORT
)
473 for (i
= 0; i
< ntokens
; i
++)
480 froms
[state
] = sp1
= sp
= XCALLOC (short, count
);
481 tos
[state
] = sp2
= XCALLOC (short, count
);
483 for (i
= 0; i
< ntokens
; i
++)
490 tally
[state
] = count
;
491 width
[state
] = sp1
[-1] - sp
[0] + 1;
495 /*------------------------------------------------------------------.
496 | Figure out the actions for the specified state, indexed by |
497 | lookahead token type. |
499 | The YYDEFACT table is output now. The detailed info is saved for |
500 | putting into YYTABLE later. |
501 `------------------------------------------------------------------*/
507 short *yydefact
= XCALLOC (short, nstates
);
509 actrow
= XCALLOC (short, ntokens
);
510 for (i
= 0; i
< nstates
; ++i
)
512 yydefact
[i
] = action_row (i
);
516 output_table_data (&output_obstack
, yydefact
,
517 yydefact
[0], 1, nstates
);
518 muscle_insert ("defact", obstack_finish (&output_obstack
));
525 /*-----------------------------.
526 | Output the actions to OOUT. |
527 `-----------------------------*/
530 actions_output (FILE *out
, size_t *line
)
533 for (rule
= 1; rule
< nrules
+ 1; ++rule
)
534 if (rule_table
[rule
].action
)
536 fprintf (out
, " case %d:\n", rule
);
539 fprintf (out
, muscle_find ("linef"),
540 rule_table
[rule
].action_line
,
541 quotearg_style (c_quoting_style
,
542 muscle_find ("filename")));
543 /* As a Bison extension, add the ending semicolon. Since some
544 Yacc don't do that, help people using bison as a Yacc
545 finding their missing semicolons. */
546 fprintf (out
, "{ %s%s }\n break;\n\n",
547 rule_table
[rule
].action
,
548 yacc_flag
? ";" : "");
550 /* We always output 4 '\n' per action. */
552 /* Plus one if !no_lines_flag. */
555 /* Get the number of lines written by the user. */
556 *line
+= get_lines_number (rule_table
[rule
].action
);
562 save_column (int symbol
, int default_state
)
571 short begin
= goto_map
[symbol
];
572 short end
= goto_map
[symbol
+ 1];
575 for (i
= begin
; i
< end
; i
++)
576 if (to_state
[i
] != default_state
)
582 symno
= symbol
- ntokens
+ nstates
;
584 froms
[symno
] = sp1
= sp
= XCALLOC (short, count
);
585 tos
[symno
] = sp2
= XCALLOC (short, count
);
587 for (i
= begin
; i
< end
; i
++)
588 if (to_state
[i
] != default_state
)
590 *sp1
++ = from_state
[i
];
591 *sp2
++ = to_state
[i
];
594 tally
[symno
] = count
;
595 width
[symno
] = sp1
[-1] - sp
[0] + 1;
599 default_goto (int symbol
)
607 m
= goto_map
[symbol
];
608 n
= goto_map
[symbol
+ 1];
613 for (i
= 0; i
< nstates
; i
++)
616 for (i
= m
; i
< n
; i
++)
617 state_count
[to_state
[i
]]++;
622 for (i
= 0; i
< nstates
; i
++)
623 if (state_count
[i
] > max
)
625 max
= state_count
[i
];
629 return default_state
;
633 /*-------------------------------------------------------------------.
634 | Figure out what to do after reducing with each rule, depending on |
635 | the saved state from before the beginning of parsing the data that |
636 | matched this rule. |
638 | The YYDEFGOTO table is output now. The detailed info is saved for |
639 | putting into YYTABLE later. |
640 `-------------------------------------------------------------------*/
646 short *yydefgoto
= XMALLOC (short, nsyms
- ntokens
);
648 state_count
= XCALLOC (short, nstates
);
649 for (i
= ntokens
; i
< nsyms
; ++i
)
651 int default_state
= default_goto (i
);
652 save_column (i
, default_state
);
653 yydefgoto
[i
- ntokens
] = default_state
;
656 output_table_data (&output_obstack
, yydefgoto
,
657 yydefgoto
[0], 1, nsyms
- ntokens
);
658 muscle_insert ("defgoto", obstack_finish (&output_obstack
));
665 /* The next few functions decide how to pack the actions and gotos
666 information into yytable. */
677 order
= XCALLOC (short, nvectors
);
680 for (i
= 0; i
< nvectors
; i
++)
687 while (j
>= 0 && (width
[order
[j
]] < w
))
690 while (j
>= 0 && (width
[order
[j
]] == w
) && (tally
[order
[j
]] < t
))
693 for (k
= nentries
- 1; k
> j
; k
--)
694 order
[k
+ 1] = order
[k
];
703 matching_state (int vector
)
720 for (prev
= vector
- 1; prev
>= 0; prev
--)
723 if (width
[j
] != w
|| tally
[j
] != t
)
727 for (k
= 0; match
&& k
< t
; k
++)
728 if (tos
[j
][k
] != tos
[i
][k
] || froms
[j
][k
] != froms
[i
][k
])
740 pack_vector (int vector
)
759 for (j
= lowzero
- from
[0]; j
< MAXTABLE
; j
++)
763 for (k
= 0; ok
&& k
< t
; k
++)
767 fatal (_("maximum table size (%d) exceeded"), MAXTABLE
);
773 for (k
= 0; ok
&& k
< vector
; k
++)
779 for (k
= 0; k
< t
; k
++)
783 check
[loc
] = from
[k
];
786 while (table
[lowzero
] != 0)
796 assert (!"pack_vector");
808 base
= XCALLOC (short, nvectors
);
809 pos
= XCALLOC (short, nentries
);
810 table
= XCALLOC (short, MAXTABLE
);
811 check
= XCALLOC (short, MAXTABLE
);
816 for (i
= 0; i
< nvectors
; i
++)
819 for (i
= 0; i
< MAXTABLE
; i
++)
822 for (i
= 0; i
< nentries
; i
++)
824 state
= matching_state (i
);
827 place
= pack_vector (i
);
832 base
[order
[i
]] = place
;
835 for (i
= 0; i
< nvectors
; i
++)
846 /* the following functions output yytable, yycheck
847 and the vectors whose elements index the portion starts */
853 output_table_data (&output_obstack
, base
,
854 base
[0], 1, nstates
);
855 muscle_insert ("pact", obstack_finish (&output_obstack
));
858 output_table_data (&output_obstack
, base
,
859 base
[nstates
], nstates
+ 1, nvectors
);
860 muscle_insert ("pgoto", obstack_finish (&output_obstack
));
869 output_table_data (&output_obstack
, table
,
870 table
[0], 1, high
+ 1);
871 muscle_insert ("table", obstack_finish (&output_obstack
));
879 output_table_data (&output_obstack
, check
,
880 check
[0], 1, high
+ 1);
881 muscle_insert ("check", obstack_finish (&output_obstack
));
885 /* compute and output yydefact, yydefgoto, yypact, yypgoto, yytable
889 output_actions (void)
892 nvectors
= nstates
+ nvars
;
894 froms
= XCALLOC (short *, nvectors
);
895 tos
= XCALLOC (short *, nvectors
);
896 tally
= XCALLOC (short, nvectors
);
897 width
= XCALLOC (short, nvectors
);
904 XFREE (goto_map
+ ntokens
);
916 for (i
= 0; i
< nstates
; ++i
)
918 XFREE (state_table
[i
]->shifts
);
919 XFREE (state_table
[i
]->reductions
);
920 XFREE (state_table
[i
]->errs
);
921 free (state_table
[i
]);
927 /*------------------------------------------------------------.
928 | Copy the parser code from SKEL_FILENAME into OOUT obstack. |
929 | and do the muscle substitution. |
930 `------------------------------------------------------------*/
933 output_parser (const char *skel_filename
, FILE *out
)
939 fskel
= xfopen (skel_filename
, "r");
941 /* New output code. */
953 else if ((c
= getc (fskel
)) == '%')
955 /* Read the muscle. */
956 const char *muscle_key
= 0;
957 const char *muscle_value
= 0;
959 while (isalnum (c
= getc (fskel
)) || c
== '-')
960 obstack_1grow (&muscle_obstack
, c
);
961 obstack_1grow (&muscle_obstack
, 0);
963 /* Output the right value, or see if it's something special. */
964 muscle_key
= obstack_finish (&muscle_obstack
);
965 muscle_value
= muscle_find (muscle_key
);
966 if (!strcmp (muscle_key
, "actions"))
967 actions_output (out
, &line
);
968 else if (!strcmp (muscle_key
, "line"))
969 fprintf (out
, "%d", line
);
970 else if (muscle_value
)
972 fputs (muscle_value
, out
);
973 line
+= get_lines_number (muscle_value
);
978 fputs (muscle_key
, out
);
989 /*----------------------------------------.
990 | Prepare the master parser to be output |
991 `----------------------------------------*/
994 output_master_parser (void)
996 FILE *parser
= xfopen (parser_file_name
, "w");
1000 skeleton
= skeleton_find ("BISON_HAIRY", BISON_HAIRY
);
1002 skeleton
= skeleton_find ("BISON_SIMPLE", BISON_SIMPLE
);
1004 muscle_insert ("skeleton", skeleton
);
1005 muscle_insert ("parser-file-name", parser_file_name
);
1007 output_parser (skeleton
, parser
);
1014 #define MUSCLE_INSERT_INT(Key, Value) \
1016 obstack_fgrow1 (&muscle_obstack, "%d", Value); \
1017 obstack_1grow (&muscle_obstack, 0); \
1018 muscle_insert (Key, obstack_finish (&muscle_obstack)); \
1021 #define MUSCLE_INSERT_STRING(Key, Value) \
1023 obstack_sgrow (&muscle_obstack, Value); \
1024 obstack_1grow (&muscle_obstack, 0); \
1025 muscle_insert (Key, obstack_finish (&muscle_obstack)); \
1028 #define MUSCLE_INSERT_PREFIX(Key, Value) \
1030 obstack_fgrow2 (&muscle_obstack, "%s%s", spec_name_prefix, Value); \
1031 obstack_1grow (&muscle_obstack, 0); \
1032 muscle_insert (Key, obstack_finish (&muscle_obstack)); \
1038 MUSCLE_INSERT_INT ("last", high
);
1039 MUSCLE_INSERT_INT ("flag", MINSHORT
);
1040 MUSCLE_INSERT_INT ("pure", pure_parser
);
1041 MUSCLE_INSERT_INT ("nsym", nsyms
);
1042 MUSCLE_INSERT_INT ("debug", debug_flag
);
1043 MUSCLE_INSERT_INT ("final", final_state
);
1044 MUSCLE_INSERT_INT ("maxtok", max_user_token_number
);
1045 MUSCLE_INSERT_INT ("ntbase", ntokens
);
1046 MUSCLE_INSERT_INT ("error-verbose", error_verbose
);
1047 MUSCLE_INSERT_STRING ("prefix", spec_name_prefix
);
1049 MUSCLE_INSERT_INT ("nnts", nvars
);
1050 MUSCLE_INSERT_INT ("nrules", nrules
);
1051 MUSCLE_INSERT_INT ("nstates", nstates
);
1052 MUSCLE_INSERT_INT ("ntokens", ntokens
);
1054 MUSCLE_INSERT_INT ("locations-flag", locations_flag
);
1058 /*-------------------------.
1059 | Output the header file. |
1060 `-------------------------*/
1063 header_output (void)
1065 FILE *out
= xfopen (spec_defines_file
, "w");
1066 char *macro_name
= compute_header_macro ();
1068 fprintf (out
, "#ifndef %s\n", macro_name
);
1069 fprintf (out
, "# define %s\n\n", macro_name
);
1071 fputs (muscle_find ("tokendef"), out
);
1076 # define YYSTYPE yystype\n\
1078 muscle_find ("stype"));
1081 fprintf (out
, "\nextern YYSTYPE %slval;\n",
1083 if (semantic_parser
)
1087 for (i
= ntokens
; i
< nsyms
; i
++)
1088 /* don't make these for dummy nonterminals made by gensym. */
1089 if (*tags
[i
] != '@')
1090 fprintf (out
, "# define\tNT%s\t%d\n", tags
[i
], i
);
1093 fprintf (out
, "\n#endif /* not %s */\n", macro_name
);
1099 /*----------------------------------------------------------.
1100 | Output the parsing tables and the parser code to ftable. |
1101 `----------------------------------------------------------*/
1106 obstack_init (&output_obstack
);
1108 output_token_translations ();
1112 if (semantic_parser
)
1114 output_rule_data ();
1115 XFREE (user_toknums
);
1119 /* Copy definitions in directive. */
1120 obstack_1grow (&attrs_obstack
, 0);
1121 muscle_insert ("prologue", obstack_finish (&attrs_obstack
));
1123 /* Output the parser. */
1124 output_master_parser ();
1125 /* Output the header if needed. */
1129 free (rule_table
+ 1);
1130 obstack_free (&muscle_obstack
, 0);
1131 obstack_free (&output_obstack
, 0);
1132 obstack_free (&action_obstack
, 0);