]> git.saurik.com Git - bison.git/blobdiff - src/conflicts.c
%expect-rr is for GLR only
[bison.git] / src / conflicts.c
index 16fa0ae0a4080ef8378fbe9a0c33c3be87ee55b8..0db0f575ef1026d14cdb28add79dca12a8c1c2dd 100644 (file)
@@ -1,24 +1,22 @@
 /* Find and resolve or report lookahead conflicts for bison,
 
-   Copyright (C) 1984, 1989, 1992, 2000, 2001, 2002, 2003, 2004, 2005, 2006
-   Free Software Foundation, Inc.
+   Copyright (C) 1984, 1989, 1992, 2000-2012 Free Software Foundation,
+   Inc.
 
    This file is part of Bison, the GNU Compiler Compiler.
 
-   Bison is free software; you can redistribute it and/or modify it
-   under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 2, or (at your option)
-   any later version.
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
 
-   Bison is distributed in the hope that it will be useful, but
-   WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-   General Public License for more details.
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
 
    You should have received a copy of the GNU General Public License
-   along with Bison; see the file COPYING.  If not, write to the Free
-   Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
-   02110-1301, USA.  */
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #include <config.h>
 #include "system.h"
@@ -32,6 +30,7 @@
 #include "getargs.h"
 #include "gram.h"
 #include "lalr.h"
+#include "print-xml.h"
 #include "reader.h"
 #include "state.h"
 #include "symtab.h"
@@ -41,6 +40,7 @@ int expected_sr_conflicts = -1;
 int expected_rr_conflicts = -1;
 static char *conflicts;
 static struct obstack solved_conflicts_obstack;
+static struct obstack solved_conflicts_xml_obstack;
 
 static bitset shift_set;
 static bitset lookahead_set;
@@ -64,81 +64,157 @@ enum conflict_resolution
 
 static inline void
 log_resolution (rule *r, symbol_number token,
-               enum conflict_resolution resolution)
+                enum conflict_resolution resolution)
 {
   if (report_flag & report_solved_conflicts)
     {
       /* The description of the resolution. */
       switch (resolution)
-       {
-       case shift_resolution:
-       case right_resolution:
-         obstack_fgrow2 (&solved_conflicts_obstack,
-                         _("\
-    Conflict between rule %d and token %s resolved as shift"),
-                         r->number,
-                         symbols[token]->tag);
-         break;
-       case reduce_resolution:
-       case left_resolution:
-         obstack_fgrow2 (&solved_conflicts_obstack,
-                         _("\
-    Conflict between rule %d and token %s resolved as reduce"),
-                         r->number,
-                         symbols[token]->tag);
-         break;
-       case nonassoc_resolution:
-         obstack_fgrow2 (&solved_conflicts_obstack,
-                         _("\
-    Conflict between rule %d and token %s resolved as an error"),
-                         r->number,
-                         symbols[token]->tag);
-         break;
-       }
+        {
+        case shift_resolution:
+        case right_resolution:
+          obstack_printf (&solved_conflicts_obstack,
+                          _("    Conflict between rule %d and token %s"
+                            " resolved as shift"),
+                          r->number,
+                          symbols[token]->tag);
+          break;
+
+        case reduce_resolution:
+        case left_resolution:
+          obstack_printf (&solved_conflicts_obstack,
+                          _("    Conflict between rule %d and token %s"
+                            " resolved as reduce"),
+                          r->number,
+                          symbols[token]->tag);
+          break;
+
+        case nonassoc_resolution:
+          obstack_printf (&solved_conflicts_obstack,
+                          _("    Conflict between rule %d and token %s"
+                            " resolved as an error"),
+                          r->number,
+                          symbols[token]->tag);
+          break;
+        }
 
       /* The reason. */
       switch (resolution)
-       {
-       case shift_resolution:
-         obstack_fgrow2 (&solved_conflicts_obstack,
-                         " (%s < %s)",
-                         r->prec->tag,
-                         symbols[token]->tag);
-         break;
-
-       case reduce_resolution:
-         obstack_fgrow2 (&solved_conflicts_obstack,
-                         " (%s < %s)",
-                         symbols[token]->tag,
-                         r->prec->tag);
-         break;
-
-       case left_resolution:
-         obstack_fgrow1 (&solved_conflicts_obstack,
-                         " (%%left %s)",
-                         symbols[token]->tag);
-         break;
-
-       case right_resolution:
-         obstack_fgrow1 (&solved_conflicts_obstack,
-                         " (%%right %s)",
-                         symbols[token]->tag);
-         break;
-       case nonassoc_resolution:
-         obstack_fgrow1 (&solved_conflicts_obstack,
-                         " (%%nonassoc %s)",
-                         symbols[token]->tag);
-         break;
-       }
+        {
+        case shift_resolution:
+          obstack_printf (&solved_conflicts_obstack,
+                          " (%s < %s)",
+                          r->prec->tag,
+                          symbols[token]->tag);
+          break;
+
+        case reduce_resolution:
+          obstack_printf (&solved_conflicts_obstack,
+                          " (%s < %s)",
+                          symbols[token]->tag,
+                          r->prec->tag);
+          break;
+
+        case left_resolution:
+          obstack_printf (&solved_conflicts_obstack,
+                          " (%%left %s)",
+                          symbols[token]->tag);
+          break;
+
+        case right_resolution:
+          obstack_printf (&solved_conflicts_obstack,
+                          " (%%right %s)",
+                          symbols[token]->tag);
+          break;
+
+        case nonassoc_resolution:
+          obstack_printf (&solved_conflicts_obstack,
+                          " (%%nonassoc %s)",
+                          symbols[token]->tag);
+          break;
+        }
+
       obstack_sgrow (&solved_conflicts_obstack, ".\n");
     }
+
+  /* XML report */
+  if (xml_flag)
+    {
+      /* The description of the resolution. */
+      switch (resolution)
+        {
+        case shift_resolution:
+        case right_resolution:
+          obstack_printf (&solved_conflicts_xml_obstack,
+                          "        <resolution rule=\"%d\" symbol=\"%s\""
+                          " type=\"shift\">",
+                          r->number,
+                          xml_escape (symbols[token]->tag));
+          break;
+
+        case reduce_resolution:
+        case left_resolution:
+          obstack_printf (&solved_conflicts_xml_obstack,
+                          "        <resolution rule=\"%d\" symbol=\"%s\""
+                          " type=\"reduce\">",
+                          r->number,
+                          xml_escape (symbols[token]->tag));
+          break;
+
+        case nonassoc_resolution:
+          obstack_printf (&solved_conflicts_xml_obstack,
+                          "        <resolution rule=\"%d\" symbol=\"%s\""
+                          " type=\"error\">",
+                          r->number,
+                          xml_escape (symbols[token]->tag));
+          break;
+        }
+
+      /* The reason. */
+      switch (resolution)
+        {
+        case shift_resolution:
+          obstack_printf (&solved_conflicts_xml_obstack,
+                          "%s &lt; %s",
+                          xml_escape_n (0, r->prec->tag),
+                          xml_escape_n (1, symbols[token]->tag));
+          break;
+
+        case reduce_resolution:
+          obstack_printf (&solved_conflicts_xml_obstack,
+                          "%s &lt; %s",
+                          xml_escape_n (0, symbols[token]->tag),
+                          xml_escape_n (1, r->prec->tag));
+          break;
+
+        case left_resolution:
+          obstack_printf (&solved_conflicts_xml_obstack,
+                          "%%left %s",
+                          xml_escape (symbols[token]->tag));
+          break;
+
+        case right_resolution:
+          obstack_printf (&solved_conflicts_xml_obstack,
+                          "%%right %s",
+                          xml_escape (symbols[token]->tag));
+          break;
+
+        case nonassoc_resolution:
+          obstack_printf (&solved_conflicts_xml_obstack,
+                          "%%nonassoc %s",
+                          xml_escape (symbols[token]->tag));
+      break;
+        }
+
+      obstack_sgrow (&solved_conflicts_xml_obstack, "</resolution>\n");
+    }
 }
 
 
 /*------------------------------------------------------------------.
 | Turn off the shift recorded for the specified token in the        |
 | specified state.  Used when we resolve a shift-reduce conflict in |
-| favor of the reduction.                                           |
+| favor of the reduction or as an error (%nonassoc).                |
 `------------------------------------------------------------------*/
 
 static void
@@ -150,15 +226,15 @@ flush_shift (state *s, int token)
   bitset_reset (lookahead_set, token);
   for (i = 0; i < trans->num; i++)
     if (!TRANSITION_IS_DISABLED (trans, i)
-       && TRANSITION_SYMBOL (trans, i) == token)
+        && TRANSITION_SYMBOL (trans, i) == token)
       TRANSITION_DISABLE (trans, i);
 }
 
 
 /*--------------------------------------------------------------------.
-| Turn off the reduce recorded for the specified token for the        |
-| specified lookahead.  Used when we resolve a shift-reduce conflict  |
-| in favor of the shift.                                              |
+| Turn off the reduce recorded for the specified token in the         |
+| specified lookahead set.  Used when we resolve a shift-reduce       |
+| conflict in favor of the shift or as an error (%nonassoc).          |
 `--------------------------------------------------------------------*/
 
 static void
@@ -176,11 +252,12 @@ flush_reduce (bitset lookahead_tokens, int token)
 |                                                                   |
 | RULENO is the number of the lookahead bitset to consider.         |
 |                                                                   |
-| ERRORS can be used to store discovered explicit errors.           |
+| ERRORS and NERRS can be used to store discovered explicit         |
+| errors.                                                           |
 `------------------------------------------------------------------*/
 
 static void
-resolve_sr_conflict (state *s, int ruleno, symbol **errors)
+resolve_sr_conflict (state *s, int ruleno, symbol **errors, int *nerrs)
 {
   symbol_number i;
   reductions *reds = s->reductions;
@@ -188,69 +265,60 @@ resolve_sr_conflict (state *s, int ruleno, symbol **errors)
   rule *redrule = reds->rules[ruleno];
   int redprec = redrule->prec->prec;
   bitset lookahead_tokens = reds->lookahead_tokens[ruleno];
-  int nerrs = 0;
 
   for (i = 0; i < ntokens; i++)
     if (bitset_test (lookahead_tokens, i)
-       && bitset_test (lookahead_set, i)
-       && symbols[i]->prec)
+        && bitset_test (lookahead_set, i)
+        && symbols[i]->prec)
       {
-       /* Shift-reduce conflict occurs for token number i
-          and it has a precedence.
-          The precedence of shifting is that of token i.  */
-       if (symbols[i]->prec < redprec)
-         {
-           log_resolution (redrule, i, reduce_resolution);
-           flush_shift (s, i);
-         }
-       else if (symbols[i]->prec > redprec)
-         {
-           log_resolution (redrule, i, shift_resolution);
-           flush_reduce (lookahead_tokens, i);
-         }
-       else
-         /* Matching precedence levels.
-            For left association, keep only the reduction.
-            For right association, keep only the shift.
-            For nonassociation, keep neither.  */
-
-         switch (symbols[i]->assoc)
-           {
-           default:
-             abort ();
-
-           case right_assoc:
-             log_resolution (redrule, i, right_resolution);
-             flush_reduce (lookahead_tokens, i);
-             break;
-
-           case left_assoc:
-             log_resolution (redrule, i, left_resolution);
-             flush_shift (s, i);
-             break;
-
-           case non_assoc:
-             log_resolution (redrule, i, nonassoc_resolution);
-             flush_shift (s, i);
-             flush_reduce (lookahead_tokens, i);
-             /* Record an explicit error for this token.  */
-             errors[nerrs++] = symbols[i];
-             break;
-           }
+        /* Shift-reduce conflict occurs for token number i
+           and it has a precedence.
+           The precedence of shifting is that of token i.  */
+        if (symbols[i]->prec < redprec)
+          {
+            log_resolution (redrule, i, reduce_resolution);
+            flush_shift (s, i);
+          }
+        else if (symbols[i]->prec > redprec)
+          {
+            log_resolution (redrule, i, shift_resolution);
+            flush_reduce (lookahead_tokens, i);
+          }
+        else
+          /* Matching precedence levels.
+             For non-defined associativity, keep both: unexpected
+             associativity conflict.
+             For left associativity, keep only the reduction.
+             For right associativity, keep only the shift.
+             For nonassociativity, keep neither.  */
+
+          switch (symbols[i]->assoc)
+            {
+            case undef_assoc:
+              abort ();
+
+            case precedence_assoc:
+              break;
+
+            case right_assoc:
+              log_resolution (redrule, i, right_resolution);
+              flush_reduce (lookahead_tokens, i);
+              break;
+
+            case left_assoc:
+              log_resolution (redrule, i, left_resolution);
+              flush_shift (s, i);
+              break;
+
+            case non_assoc:
+              log_resolution (redrule, i, nonassoc_resolution);
+              flush_shift (s, i);
+              flush_reduce (lookahead_tokens, i);
+              /* Record an explicit error for this token.  */
+              errors[(*nerrs)++] = symbols[i];
+              break;
+            }
       }
-
-  if (nerrs)
-    {
-      /* Some tokens have been explicitly made errors.  Allocate a
-        permanent errs structure for this state, to record them.  */
-      state_errs_set (s, nerrs, errors);
-    }
-
-  if (obstack_object_size (&solved_conflicts_obstack))
-    {
-      obstack_1grow (&solved_conflicts_obstack, '\0');
-      s->solved_conflicts = obstack_finish (&solved_conflicts_obstack);
-    }
 }
 
 
@@ -267,6 +335,7 @@ set_conflicts (state *s, symbol **errors)
   int i;
   transitions *trans = s->transitions;
   reductions *reds = s->reductions;
+  int nerrs = 0;
 
   if (s->consistent)
     return;
@@ -281,16 +350,26 @@ set_conflicts (state *s, symbol **errors)
      precedence.  */
   for (i = 0; i < reds->num; ++i)
     if (reds->rules[i]->prec && reds->rules[i]->prec->prec
-       && !bitset_disjoint_p (reds->lookahead_tokens[i], lookahead_set))
-      resolve_sr_conflict (s, i, errors);
+        && !bitset_disjoint_p (reds->lookahead_tokens[i], lookahead_set))
+      resolve_sr_conflict (s, i, errors, &nerrs);
+
+  if (nerrs)
+    {
+      /* Some tokens have been explicitly made errors.  Allocate a
+         permanent errs structure for this state, to record them.  */
+      state_errs_set (s, nerrs, errors);
+    }
+  if (obstack_object_size (&solved_conflicts_obstack))
+    s->solved_conflicts = obstack_finish0 (&solved_conflicts_obstack);
+  if (obstack_object_size (&solved_conflicts_xml_obstack))
+    s->solved_conflicts_xml = obstack_finish0 (&solved_conflicts_xml_obstack);
 
   /* Loop over all rules which require lookahead in this state.  Check
      for conflicts not resolved above.  */
   for (i = 0; i < reds->num; ++i)
     {
       if (!bitset_disjoint_p (reds->lookahead_tokens[i], lookahead_set))
-       conflicts[s->number] = 1;
-
+        conflicts[s->number] = 1;
       bitset_or (lookahead_set, lookahead_set, reds->lookahead_tokens[i]);
     }
 }
@@ -312,15 +391,16 @@ conflicts_solve (void)
   shift_set = bitset_create (ntokens, BITSET_FIXED);
   lookahead_set = bitset_create (ntokens, BITSET_FIXED);
   obstack_init (&solved_conflicts_obstack);
+  obstack_init (&solved_conflicts_xml_obstack);
 
   for (i = 0; i < nstates; i++)
     {
       set_conflicts (states[i], errors);
 
       /* For uniformity of the code, make sure all the states have a valid
-        `errs' member.  */
+         `errs' member.  */
       if (!states[i]->errs)
-       states[i]->errs = errs_new (0, 0);
+        states[i]->errs = errs_new (0, 0);
     }
 
   free (errors);
@@ -331,7 +411,8 @@ void
 conflicts_update_state_numbers (state_number old_to_new[],
                                 state_number nstates_old)
 {
-  for (state_number i = 0; i < nstates_old; ++i)
+  state_number i;
+  for (i = 0; i < nstates_old; ++i)
     if (old_to_new[i] != nstates_old)
       conflicts[old_to_new[i]] = conflicts[i];
 }
@@ -388,11 +469,11 @@ count_rr_conflicts (state *s, bool one_per_token)
       int count = 0;
       int j;
       for (j = 0; j < reds->num; ++j)
-       if (bitset_test (reds->lookahead_tokens[j], i))
-         count++;
+        if (bitset_test (reds->lookahead_tokens[j], i))
+          count++;
 
       if (count >= 2)
-       rrc_count += one_per_token ? 1 : count-1;
+        rrc_count += one_per_token ? 1 : count-1;
     }
 
   return rrc_count;
@@ -408,7 +489,7 @@ conflict_report (FILE *out, int src_num, int rrc_num)
 {
   if (src_num && rrc_num)
     fprintf (out, _("conflicts: %d shift/reduce, %d reduce/reduce\n"),
-            src_num, rrc_num);
+             src_num, rrc_num);
   else if (src_num)
     fprintf (out, _("conflicts: %d shift/reduce\n"), src_num);
   else if (rrc_num)
@@ -429,12 +510,12 @@ conflicts_output (FILE *out)
     {
       state *s = states[i];
       if (conflicts[i])
-       {
-         fprintf (out, _("State %d "), i);
-         conflict_report (out, count_sr_conflicts (s),
-                          count_rr_conflicts (s, true));
-         printed_sth = true;
-       }
+        {
+          fprintf (out, _("State %d "), i);
+          conflict_report (out, count_sr_conflicts (s),
+                           count_rr_conflicts (s, true));
+          printed_sth = true;
+        }
     }
   if (printed_sth)
     fputs ("\n\n", out);
@@ -444,7 +525,7 @@ conflicts_output (FILE *out)
 | Total the number of S/R and R/R conflicts.  Unlike the  |
 | code in conflicts_output, however, count EACH pair of   |
 | reductions for the same state and lookahead as one      |
-| conflict.                                              |
+| conflict.                                               |
 `--------------------------------------------------------*/
 
 int
@@ -458,8 +539,8 @@ conflicts_total_count (void)
   for (i = 0; i < nstates; i++)
     if (conflicts[i])
       {
-       count += count_sr_conflicts (states[i]);
-       count += count_rr_conflicts (states[i], false);
+        count += count_sr_conflicts (states[i]);
+        count += count_rr_conflicts (states[i], false);
       }
   return count;
 }
@@ -489,15 +570,15 @@ conflicts_print (void)
 
     for (i = 0; i < nstates; i++)
       if (conflicts[i])
-       {
-         src_total += count_sr_conflicts (states[i]);
-         rrc_total += count_rr_conflicts (states[i], true);
-       }
+        {
+          src_total += count_sr_conflicts (states[i]);
+          rrc_total += count_rr_conflicts (states[i], true);
+        }
   }
 
-  if (! glr_parser && rrc_total > 0 && expected_rr_conflicts != -1)
+  if (! glr_parser && expected_rr_conflicts != -1)
     {
-      warn (_("%%expect-rr applies only to GLR parsers"));
+      complain (Wother, _("%%expect-rr applies only to GLR parsers"));
       expected_rr_conflicts = -1;
     }
 
@@ -512,25 +593,34 @@ conflicts_print (void)
     return;
 
   /* Report the total number of conflicts on STDERR.  */
+  if (expected_sr_conflicts == -1 && expected_rr_conflicts == -1)
+    {
+      if (!(warnings_flag & Wconflicts_sr))
+        src_total = 0;
+      if (!(warnings_flag & Wconflicts_rr))
+        rrc_total = 0;
+    }
   if (src_total | rrc_total)
     {
+      if (expected_sr_conflicts == -1 && expected_rr_conflicts == -1)
+        set_warning_issued ();
       if (! yacc_flag)
-       fprintf (stderr, "%s: ", current_file);
+        fprintf (stderr, "%s: ", current_file);
       conflict_report (stderr, src_total, rrc_total);
     }
 
   if (expected_sr_conflicts != -1 || expected_rr_conflicts != -1)
     {
       if (! src_ok)
-       complain (ngettext ("expected %d shift/reduce conflict",
-                           "expected %d shift/reduce conflicts",
-                           src_expected),
-                 src_expected);
+        complain (complaint, ngettext ("expected %d shift/reduce conflict",
+                                       "expected %d shift/reduce conflicts",
+                                       src_expected),
+                  src_expected);
       if (! rrc_ok)
-       complain (ngettext ("expected %d reduce/reduce conflict",
-                           "expected %d reduce/reduce conflicts",
-                           rrc_expected),
-                 rrc_expected);
+        complain (complaint, ngettext ("expected %d reduce/reduce conflict",
+                                       "expected %d reduce/reduce conflicts",
+                                       rrc_expected),
+                  rrc_expected);
     }
 }
 
@@ -542,4 +632,5 @@ conflicts_free (void)
   bitset_free (shift_set);
   bitset_free (lookahead_set);
   obstack_free (&solved_conflicts_obstack, NULL);
+  obstack_free (&solved_conflicts_xml_obstack, NULL);
 }