FYI: %nondeterministic-parser

[Akim Demaille]

Hi,

This change is needed for work in progress: the ability to generate
nondeterministic tables with other skeletons than just glr.c.  It is
premature to document it.


Index: ChangeLog
from  Akim Demaille  <address@hidden>

        * src/gram.h, src/gram.c (pure_parser, glr_parser): Move to...
        * src/getargs.c, src/getargs.h: here, as bool, not int.
        (nondeterministic_parser): New.
        * src/parse-gram.y, src/scan-gram.l: Support
        %nondeterministic-parser.
        * src/output.c (prepare): Use nondeterministic_parser instead
        of glr_parser where appropriate.
        * src/tables.c (conflict_row, action_row, save_row)
        (token_actions, token_actions, pack_vector): Ditto.

 2003-04-29  Akim Demaille  <address@hidden>
Index: src/getargs.c
===================================================================
RCS file: /cvsroot/bison/bison/src/getargs.c,v
retrieving revision 1.55
diff -u -u -r1.55 getargs.c
--- src/getargs.c 11 Jan 2003 08:11:32 -0000 1.55
+++ src/getargs.c 29 Apr 2003 12:52:08 -0000
@@ -54,6 +54,10 @@
 int graph_flag = 0;
 int trace_flag = trace_none;
 
+bool nondeterministic_parser = false;
+bool glr_parser = false;
+bool pure_parser = false;
+
 const char *skeleton = NULL;
 const char *include = NULL;
 
Index: src/getargs.h
===================================================================
RCS file: /cvsroot/bison/bison/src/getargs.h,v
retrieving revision 1.23
diff -u -u -r1.23 getargs.h
--- src/getargs.h 11 Dec 2002 06:31:14 -0000 1.23
+++ src/getargs.h 29 Apr 2003 12:52:08 -0000
@@ -1,5 +1,5 @@
 /* Parse command line arguments for bison.
-   Copyright (C) 1984, 1986, 1989, 1992, 2000, 2001, 2002
+   Copyright (C) 1984, 1986, 1989, 1992, 2000, 2001, 2002, 2003
    Free Software Foundation, Inc.
 
    This file is part of Bison, the GNU Compiler Compiler.
@@ -34,6 +34,23 @@
 extern int token_table_flag;           /* for -k */
 extern int graph_flag;         /* for -g */
 extern int yacc_flag;                  /* for -y */
+
+/* GLR_PARSER is true if the input file says to use the GLR
+   (Generalized LR) parser, and to output some additional information
+   used by the GLR algorithm.  */
+
+extern bool glr_parser;
+
+/* PURE_PARSER is true if should generate a parser that is all pure
+   and reentrant.  */
+
+extern bool pure_parser;
+
+/* NONDETERMINISTIC_PARSER is true iff conflicts are accepted.  This
+   is used by the GLR parser, and might be used in BackTracking
+   parsers too.  */
+
+extern bool nondeterministic_parser;
 
 /* --trace.  */
 enum trace
Index: src/gram.c
===================================================================
RCS file: /cvsroot/bison/bison/src/gram.c,v
retrieving revision 1.51
diff -u -u -r1.51 gram.c
--- src/gram.c 3 Feb 2003 15:35:56 -0000 1.51
+++ src/gram.c 29 Apr 2003 12:52:09 -0000
@@ -47,10 +47,6 @@
 
 int max_user_token_number = 256;
 
-int glr_parser = 0;
-int pure_parser = 0;
-
-
 /*--------------------------------------------------------------.
 | Return true IFF the rule has a `number' smaller than NRULES.  |
 `--------------------------------------------------------------*/
Index: src/gram.h
===================================================================
RCS file: /cvsroot/bison/bison/src/gram.h,v
retrieving revision 1.53
diff -u -u -r1.53 gram.h
--- src/gram.h 3 Feb 2003 15:33:19 -0000 1.53
+++ src/gram.h 29 Apr 2003 12:52:09 -0000
@@ -231,17 +231,6 @@
 
 
 
-/* GLR_PARSER is nonzero if the input file says to use the GLR
-   (Generalized LR) parser, and to output some additional
-   information used by the GLR algorithm. */
-
-extern int glr_parser;
-
-/* PURE_PARSER is nonzero if should generate a parser that is all pure
-   and reentrant.  */
-
-extern int pure_parser;
-
 /* Dump RITEM for traces. */
 void ritem_print (FILE *out);
 
Index: src/output.c
===================================================================
RCS file: /cvsroot/bison/bison/src/output.c,v
retrieving revision 1.219
diff -u -u -r1.219 output.c
--- src/output.c 31 Mar 2003 09:17:40 -0000 1.219
+++ src/output.c 29 Apr 2003 12:52:09 -0000
@@ -614,7 +614,7 @@
   /* Find the right skeleton file.  */
   if (!skeleton)
     {
-      if (glr_parser)
+      if (glr_parser || nondeterministic_parser)
        skeleton = "glr.c";
       else
        skeleton = "yacc.c";
Index: src/parse-gram.y
===================================================================
RCS file: /cvsroot/bison/bison/src/parse-gram.y,v
retrieving revision 1.39
diff -u -u -r1.39 parse-gram.y
--- src/parse-gram.y 3 Feb 2003 15:35:56 -0000 1.39
+++ src/parse-gram.y 29 Apr 2003 12:52:10 -0000
@@ -120,6 +120,7 @@
   PERCENT_LOCATIONS     "%locations"
   PERCENT_NAME_PREFIX   "%name-prefix"
   PERCENT_NO_LINES      "%no-lines"
+  PERCENT_NONDETERMINISTIC_PARSER    "%nondeterministic-parser"
   PERCENT_OUTPUT        "%output"
   PERCENT_PARSE_PARAM   "%parse-param {...}"
   PERCENT_PURE_PARSER   "%pure-parser"
@@ -180,14 +181,16 @@
 | "%error-verbose"                         { error_verbose = 1; }
 | "%expect" INT                            { expected_conflicts = $2; }
 | "%file-prefix" "=" string_content        { spec_file_prefix = $3; }
-| "%glr-parser"                           { glr_parser = 1; }
+| "%glr-parser"                           { nondeterministic_parser = true;
+                                             glr_parser = true; }
 | "%lex-param {...}"                      { add_param ("lex_param", $1, @1); }
 | "%locations"                             { locations_flag = 1; }
 | "%name-prefix" "=" string_content        { spec_name_prefix = $3; }
 | "%no-lines"                              { no_lines_flag = 1; }
+| "%nondeterministic-parser"              { nondeterministic_parser = true; }
 | "%output" "=" string_content             { spec_outfile = $3; }
 | "%parse-param {...}"                  { add_param ("parse_param", $1, @1); }
-| "%pure-parser"                           { pure_parser = 1; }
+| "%pure-parser"                           { pure_parser = true; }
 | "%skeleton" string_content               { skeleton = $2; }
 | "%token-table"                           { token_table_flag = 1; }
 | "%verbose"                               { report_flag = report_states; }
Index: src/scan-gram.l
===================================================================
RCS file: /cvsroot/bison/bison/src/scan-gram.l,v
retrieving revision 1.59
diff -u -u -r1.59 scan-gram.l
--- src/scan-gram.l 18 Apr 2003 07:26:19 -0000 1.59
+++ src/scan-gram.l 29 Apr 2003 12:52:11 -0000
@@ -198,6 +198,7 @@
   "%name"[-_]"prefix"     return PERCENT_NAME_PREFIX;
   "%no"[-_]"lines"        return PERCENT_NO_LINES;
   "%nonassoc"             return PERCENT_NONASSOC;
+  "%nondeterministic-parser"   return PERCENT_NONDETERMINISTIC_PARSER;
   "%nterm"                return PERCENT_NTERM;
   "%output"               return PERCENT_OUTPUT;
   "%parse-param"         token_type = PERCENT_PARSE_PARAM; BEGIN SC_PRE_CODE;
Index: src/tables.c
===================================================================
RCS file: /cvsroot/bison/bison/src/tables.c,v
retrieving revision 1.17
diff -u -u -r1.17 tables.c
--- src/tables.c 3 Feb 2003 15:35:57 -0000 1.17
+++ src/tables.c 29 Apr 2003 12:52:13 -0000
@@ -183,7 +183,7 @@
   int i, j;
   reductions *reds = s->reductions;
 
-  if (! glr_parser)
+  if (!nondeterministic_parser)
     return;
 
   for (j = 0; j < ntokens; j += 1)
@@ -334,7 +334,7 @@
              int j;
              for (j = 0; j < ntokens; j++)
                if (actrow[j] == rule_number_as_item_number 
(default_rule->number)
-                   && ! (glr_parser && conflrow[j]))
+                   && ! (nondeterministic_parser && conflrow[j]))
                  actrow[j] = 0;
            }
        }
@@ -381,7 +381,7 @@
   /* Allocate non defaulted actions.  */
   froms[s] = sp = CALLOC (sp1, count);
   tos[s] = CALLOC (sp2, count);
-  conflict_tos[s] = glr_parser ? CALLOC (sp3, count) : NULL;
+  conflict_tos[s] = nondeterministic_parser ? CALLOC (sp3, count) : NULL;
 
   /* Store non defaulted actions.  */
   for (i = 0; i < ntokens; i++)
@@ -389,7 +389,7 @@
       {
        *sp1++ = i;
        *sp2++ = actrow[i];
-       if (glr_parser)
+       if (nondeterministic_parser)
          *sp3++ = conflrow[i];
       }
 
@@ -413,7 +413,7 @@
   symbol_number j;
   rule_number r;
 
-  int nconflict = glr_parser ? conflicts_total_count () : 0;
+  int nconflict = nondeterministic_parser ? conflicts_total_count () : 0;
 
   CALLOC (yydefact, nstates);
 
@@ -425,7 +425,7 @@
   conflict_list_cnt = 1;
 
   /* Find the rules which are reduced.  */
-  if (!glr_parser)
+  if (!nondeterministic_parser)
     for (r = 0; r < nrules; ++r)
       rules[r].useful = false;
 
@@ -438,7 +438,7 @@
       /* Now that the parser was computed, we can find which rules are
         really reduced, and which are not because of SR or RR
         conflicts.  */
-      if (!glr_parser)
+      if (!nondeterministic_parser)
        {
          for (j = 0; j < ntokens; ++j)
            if (actrow[j] < 0 && actrow[j] != ACTION_NUMBER_MINIMUM)
@@ -663,7 +663,7 @@
   base_number *to = tos[i];
   unsigned int *conflict_to = conflict_tos[i];
 
-  if (! t)
+  if (!t)
     abort ();
 
   for (j = lowzero - from[0]; ; j++)
@@ -694,7 +694,7 @@
            {
              loc = j + from[k];
              table[loc] = to[k];
-             if (glr_parser && conflict_to != NULL)
+             if (nondeterministic_parser && conflict_to != NULL)
                conflict_table[loc] = conflict_to[k];
              check[loc] = from[k];
            }