X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/52afa962d1e74968713f6b04123512f445f19851..d140056923f4942c645cf56e0f6940e28113cfdd:/src/conflicts.c

diff --git a/src/conflicts.c b/src/conflicts.c
index bb6f8ac7..0db0f575 100644
--- a/src/conflicts.c
+++ b/src/conflicts.c
@@ -1,77 +1,246 @@
-/* Find and resolve or report look-ahead conflicts for bison,
-   Copyright 1984, 1989, 1992, 2000, 2001 Free Software Foundation, Inc.
+/* Find and resolve or report lookahead conflicts for bison,
+
+   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., 59 Temple Place - Suite 330, Boston, MA
-   02111-1307, USA.  */
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 
+#include <config.h>
 #include "system.h"
+
+#include <bitset.h>
+
+#include "LR0.h"
 #include "complain.h"
-#include "getargs.h"
+#include "conflicts.h"
 #include "files.h"
+#include "getargs.h"
 #include "gram.h"
-#include "state.h"
 #include "lalr.h"
-#include "conflicts.h"
+#include "print-xml.h"
 #include "reader.h"
-#include "LR0.h"
+#include "state.h"
+#include "symtab.h"
 
-errs **err_table = NULL;
 /* -1 stands for not specified. */
-int expected_conflicts = -1;
-static char *conflicts = NULL;
+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;
 
-static unsigned *shiftset = NULL;
-static unsigned *lookaheadset = NULL;
 
 
+enum conflict_resolution
+  {
+    shift_resolution,
+    reduce_resolution,
+    left_resolution,
+    right_resolution,
+    nonassoc_resolution
+  };
+
+
+/*----------------------------------------------------------------.
+| Explain how an SR conflict between TOKEN and RULE was resolved: |
+| RESOLUTION.                                                     |
+`----------------------------------------------------------------*/
+
 static inline void
-log_resolution (int state, int LAno, int token, char *resolution)
+log_resolution (rule *r, symbol_number token,
+                enum conflict_resolution resolution)
 {
-  obstack_fgrow4 (&output_obstack,
-		  _("\
-Conflict in state %d between rule %d and token %s resolved as %s.\n"),
-		  state, LAruleno[LAno], tags[token], resolution);
+  if (report_flag & report_solved_conflicts)
+    {
+      /* The description of the resolution. */
+      switch (resolution)
+        {
+        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_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
-flush_shift (int state, int token)
+flush_shift (state *s, int token)
 {
-  shifts *shiftp;
-  int k, i;
+  transitions *trans = s->transitions;
+  int i;
 
-  shiftp = state_table[state].shift_table;
+  bitset_reset (lookahead_set, token);
+  for (i = 0; i < trans->num; i++)
+    if (!TRANSITION_IS_DISABLED (trans, i)
+        && TRANSITION_SYMBOL (trans, i) == token)
+      TRANSITION_DISABLE (trans, i);
+}
 
-  if (shiftp)
-    {
-      k = shiftp->nshifts;
-      for (i = 0; i < k; i++)
-	{
-	  if (shiftp->shifts[i]
-	      && token == state_table[shiftp->shifts[i]].accessing_symbol)
-	    (shiftp->shifts[i]) = 0;
-	}
-    }
+
+/*--------------------------------------------------------------------.
+| 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
+flush_reduce (bitset lookahead_tokens, int token)
+{
+  bitset_reset (lookahead_tokens, token);
 }
 
 
@@ -80,171 +249,172 @@ flush_shift (int state, int token)
 | precedence declarations.  It has already been checked that the    |
 | rule has a precedence.  A conflict is resolved by modifying the   |
 | shift or reduce tables so that there is no longer a conflict.     |
+|                                                                   |
+| RULENO is the number of the lookahead bitset to consider.         |
+|                                                                   |
+| ERRORS and NERRS can be used to store discovered explicit         |
+| errors.                                                           |
 `------------------------------------------------------------------*/
 
 static void
-resolve_sr_conflict (int state, int lookaheadnum)
+resolve_sr_conflict (state *s, int ruleno, symbol **errors, int *nerrs)
 {
-  int i;
-  int mask;
-  unsigned *fp1;
-  unsigned *fp2;
-  int redprec;
-  errs *errp = ERRS_ALLOC (ntokens + 1);
-  short *errtokens = errp->errs;
-
-  /* find the rule to reduce by to get precedence of reduction  */
-  redprec = rule_table[LAruleno[lookaheadnum]].prec;
-
-  mask = 1;
-  fp1 = LA (lookaheadnum);
-  fp2 = lookaheadset;
+  symbol_number i;
+  reductions *reds = s->reductions;
+  /* Find the rule to reduce by to get precedence of reduction.  */
+  rule *redrule = reds->rules[ruleno];
+  int redprec = redrule->prec->prec;
+  bitset lookahead_tokens = reds->lookahead_tokens[ruleno];
+
   for (i = 0; i < ntokens; i++)
-    {
-      if ((mask & *fp2 & *fp1) && sprec[i])
-	/* Shift-reduce conflict occurs for token number i
-	   and it has a precedence.
-	   The precedence of shifting is that of token i.  */
-	{
-	  if (sprec[i] < redprec)
-	    {
-	      log_resolution (state, lookaheadnum, i, _("reduce"));
-	      *fp2 &= ~mask;	/* flush the shift for this token */
-	      flush_shift (state, i);
-	    }
-	  else if (sprec[i] > redprec)
-	    {
-	      log_resolution (state, lookaheadnum, i, _("shift"));
-	      *fp1 &= ~mask;	/* flush the reduce for this token */
-	    }
-	  else
-	    {
-	      /* Matching precedence levels.
-	         For left association, keep only the reduction.
-	         For right association, keep only the shift.
-	         For nonassociation, keep neither.  */
-
-	      switch (sassoc[i])
-		{
-		case right_assoc:
-		  log_resolution (state, lookaheadnum, i, _("shift"));
-		  break;
-
-		case left_assoc:
-		  log_resolution (state, lookaheadnum, i, _("reduce"));
-		  break;
-
-		case non_assoc:
-		  log_resolution (state, lookaheadnum, i, _("an error"));
-		  break;
-		}
-
-	      if (sassoc[i] != right_assoc)
-		{
-		  *fp2 &= ~mask;	/* flush the shift for this token */
-		  flush_shift (state, i);
-		}
-	      if (sassoc[i] != left_assoc)
-		{
-		  *fp1 &= ~mask;	/* flush the reduce for this token */
-		}
-	      if (sassoc[i] == non_assoc)
-		{
-		  /* Record an explicit error for this token.  */
-		  *errtokens++ = i;
-		}
-	    }
-	}
-
-      mask <<= 1;
-      if (mask == 0)
-	{
-	  mask = 1;
-	  fp2++;
-	  fp1++;
-	}
-    }
-  errp->nerrs = errtokens - errp->errs;
-  if (errp->nerrs)
-    {
-      /* Some tokens have been explicitly made errors.  Allocate
-         a permanent errs structure for this state, to record them.  */
-      i = (char *) errtokens - (char *) errp;
-      err_table[state] = ERRS_ALLOC (i + 1);
-      bcopy (errp, err_table[state], i);
-    }
-  else
-    err_table[state] = 0;
-  free (errp);
+    if (bitset_test (lookahead_tokens, i)
+        && 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 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;
+            }
+      }
 }
 
 
+/*-------------------------------------------------------------------.
+| Solve the S/R conflicts of state S using the                       |
+| precedence/associativity, and flag it inconsistent if it still has |
+| conflicts.  ERRORS can be used as storage to compute the list of   |
+| lookahead tokens on which S raises a syntax error (%nonassoc).     |
+`-------------------------------------------------------------------*/
+
 static void
-set_conflicts (int state)
+set_conflicts (state *s, symbol **errors)
 {
-  int i, j;
-  shifts *shiftp;
-  int symbol;
+  int i;
+  transitions *trans = s->transitions;
+  reductions *reds = s->reductions;
+  int nerrs = 0;
 
-  if (state_table[state].consistent)
+  if (s->consistent)
     return;
 
-  for (i = 0; i < tokensetsize; i++)
-    lookaheadset[i] = 0;
+  bitset_zero (lookahead_set);
 
-  shiftp = state_table[state].shift_table;
-  if (shiftp)
-    for (i = 0; i < shiftp->nshifts; i++)
-      {
-	symbol = state_table[shiftp->shifts[i]].accessing_symbol;
-	if (ISVAR (symbol))
-	  break;
-	SETBIT (lookaheadset, symbol);
-      }
+  FOR_EACH_SHIFT (trans, i)
+    bitset_set (lookahead_set, TRANSITION_SYMBOL (trans, i));
 
   /* Loop over all rules which require lookahead in this state.  First
      check for shift-reduce conflict, and try to resolve using
-     precedence */
-  for (i = state_table[state].lookaheads;
-       i < state_table[state + 1].lookaheads;
-       ++i)
-    if (rule_table[LAruleno[i]].prec)
-      for (j = 0; j < tokensetsize; ++j)
-	if (LA (i)[j] & lookaheadset[j])
-	  {
-	    resolve_sr_conflict (state, i);
-	    break;
-	  }
+     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, &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 = state_table[state].lookaheads;
-       i < state_table[state + 1].lookaheads;
-       ++i)
+  for (i = 0; i < reds->num; ++i)
     {
-      for (j = 0; j < tokensetsize; ++j)
-	if (LA (i)[j] & lookaheadset[j])
-	  conflicts[state] = 1;
-
-      for (j = 0; j < tokensetsize; ++j)
-	lookaheadset[j] |= LA (i)[j];
+      if (!bitset_disjoint_p (reds->lookahead_tokens[i], lookahead_set))
+        conflicts[s->number] = 1;
+      bitset_or (lookahead_set, lookahead_set, reds->lookahead_tokens[i]);
     }
 }
 
+
+/*----------------------------------------------------------------.
+| Solve all the S/R conflicts using the precedence/associativity, |
+| and flag as inconsistent the states that still have conflicts.  |
+`----------------------------------------------------------------*/
+
 void
-solve_conflicts (void)
+conflicts_solve (void)
 {
-  int i;
-
-  conflicts = XCALLOC (char, nstates);
-  shiftset = XCALLOC (unsigned, tokensetsize);
-  lookaheadset = XCALLOC (unsigned, tokensetsize);
+  state_number i;
+  /* List of lookahead tokens on which we explicitly raise a syntax error.  */
+  symbol **errors = xnmalloc (ntokens + 1, sizeof *errors);
 
-  err_table = XCALLOC (errs *, nstates);
+  conflicts = xcalloc (nstates, sizeof *conflicts);
+  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 (i);
+    {
+      set_conflicts (states[i], errors);
+
+      /* For uniformity of the code, make sure all the states have a valid
+         `errs' member.  */
+      if (!states[i]->errs)
+        states[i]->errs = errs_new (0, 0);
+    }
+
+  free (errors);
+}
+
+
+void
+conflicts_update_state_numbers (state_number old_to_new[],
+                                state_number nstates_old)
+{
+  state_number i;
+  for (i = 0; i < nstates_old; ++i)
+    if (old_to_new[i] != nstates_old)
+      conflicts[old_to_new[i]] = conflicts[i];
 }
 
 
@@ -253,111 +423,77 @@ solve_conflicts (void)
 `---------------------------------------------*/
 
 static int
-count_sr_conflicts (int state)
+count_sr_conflicts (state *s)
 {
-  int i, k;
+  int i;
   int src_count = 0;
-  shifts *shiftp = state_table[state].shift_table;
+  transitions *trans = s->transitions;
+  reductions *reds = s->reductions;
 
-  if (!shiftp)
+  if (!trans)
     return 0;
 
-  for (i = 0; i < tokensetsize; i++)
-    {
-      shiftset[i] = 0;
-      lookaheadset[i] = 0;
-    }
+  bitset_zero (lookahead_set);
+  bitset_zero (shift_set);
 
-  for (i = 0; i < shiftp->nshifts && SHIFT_IS_SHIFT (shiftp, i); i++)
-    {
-      int symbol = state_table[shiftp->shifts[i]].accessing_symbol;
-      SETBIT (shiftset, symbol);
-    }
+  FOR_EACH_SHIFT (trans, i)
+    bitset_set (shift_set, TRANSITION_SYMBOL (trans, i));
 
-  for (i = state_table[state].lookaheads;
-       i < state_table[state + 1].lookaheads;
-       ++i)
-    for (k = 0; k < tokensetsize; ++k)
-      lookaheadset[k] |= LA (i)[k];
+  for (i = 0; i < reds->num; ++i)
+    bitset_or (lookahead_set, lookahead_set, reds->lookahead_tokens[i]);
 
-  for (k = 0; k < tokensetsize; ++k)
-    lookaheadset[k] &= shiftset[k];
+  bitset_and (lookahead_set, lookahead_set, shift_set);
 
-  for (i = 0; i < ntokens; i++)
-    if (BITISSET (lookaheadset, i))
-      src_count++;
+  src_count = bitset_count (lookahead_set);
 
   return src_count;
 }
 
 
-/*----------------------------------------------.
-| Count the number of reduce/reduce conflicts.  |
-`----------------------------------------------*/
+/*----------------------------------------------------------------.
+| Count the number of reduce/reduce conflicts.  If ONE_PER_TOKEN, |
+| count one conflict for each token that has any reduce/reduce    |
+| conflicts.  Otherwise, count one conflict for each pair of      |
+| conflicting reductions.                                         |
++`----------------------------------------------------------------*/
 
 static int
-count_rr_conflicts (int state)
+count_rr_conflicts (state *s, bool one_per_token)
 {
   int i;
+  reductions *reds = s->reductions;
   int rrc_count = 0;
 
-  int m = state_table[state].lookaheads;
-  int n = state_table[state + 1].lookaheads;
-
-  if (n - m < 2)
-    return 0;
-
   for (i = 0; i < ntokens; i++)
     {
       int count = 0;
       int j;
-      for (j = m; j < n; j++)
-	if (BITISSET (LA (m), j))
-	  count++;
+      for (j = 0; j < reds->num; ++j)
+        if (bitset_test (reds->lookahead_tokens[j], i))
+          count++;
 
       if (count >= 2)
-	rrc_count++;
+        rrc_count += one_per_token ? 1 : count-1;
     }
 
   return rrc_count;
 }
 
-/*--------------------------------------------------------------.
-| Return a human readable string which reports shift/reduce and |
-| reduce/reduce conflict numbers (SRC_NUM, RRC_NUM).            |
-`--------------------------------------------------------------*/
-
-static const char *
-conflict_report (int src_num, int rrc_num)
-{
-  static char res[4096];
-  char *cp = res;
-
-  if (src_num >= 1)
-    {
-      sprintf (cp, ngettext ("%d shift/reduce conflict",
-			     "%d shift/reduce conflicts", src_num), src_num);
-      cp += strlen (cp);
-    }
-
-  if (src_num > 0 && rrc_num > 0)
-    {
-      sprintf (cp, " %s ", _("and"));
-      cp += strlen (cp);
-    }
-
-  if (rrc_num >= 1)
-    {
-      sprintf (cp, ngettext ("%d reduce/reduce conflict",
-			     "%d reduce/reduce conflicts", rrc_num), rrc_num);
-      cp += strlen (cp);
-    }
 
-  *cp++ = '.';
-  *cp++ = '\n';
-  *cp++ = '\0';
+/*--------------------------------------------------------.
+| Report the number of conflicts, using the Yacc format.  |
+`--------------------------------------------------------*/
 
-  return res;
+static void
+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);
+  else if (src_num)
+    fprintf (out, _("conflicts: %d shift/reduce\n"), src_num);
+  else if (rrc_num)
+    fprintf (out, _("conflicts: %d reduce/reduce\n"), rrc_num);
 }
 
 
@@ -368,18 +504,45 @@ conflict_report (int src_num, int rrc_num)
 void
 conflicts_output (FILE *out)
 {
-  bool printed_sth = FALSE;
-  int i;
+  bool printed_sth = false;
+  state_number i;
+  for (i = 0; i < nstates; i++)
+    {
+      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;
+        }
+    }
+  if (printed_sth)
+    fputs ("\n\n", 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.                                               |
+`--------------------------------------------------------*/
+
+int
+conflicts_total_count (void)
+{
+  state_number i;
+  int count;
+
+  /* Conflicts by state.  */
+  count = 0;
   for (i = 0; i < nstates; i++)
     if (conflicts[i])
       {
-	fprintf (out, _("State %d contains "), i);
-	fputs (conflict_report (count_sr_conflicts (i),
-				count_rr_conflicts (i)), out);
-	printed_sth = TRUE;
+        count += count_sr_conflicts (states[i]);
+        count += count_rr_conflicts (states[i], false);
       }
-  if (printed_sth)
-    fputs ("\n\n", out);
+  return count;
 }
 
 
@@ -390,216 +553,84 @@ conflicts_output (FILE *out)
 void
 conflicts_print (void)
 {
-  int i;
-
   /* Is the number of SR conflicts OK?  Either EXPECTED_CONFLICTS is
      not set, and then we want 0 SR, or else it is specified, in which
      case we want equality.  */
-  int src_ok = 0;
+  bool src_ok;
+  bool rrc_ok;
 
   int src_total = 0;
   int rrc_total = 0;
+  int src_expected;
+  int rrc_expected;
 
   /* Conflicts by state.  */
-  for (i = 0; i < nstates; i++)
-    if (conflicts[i])
-      {
-	src_total += count_sr_conflicts (i);
-	rrc_total += count_rr_conflicts (i);
-      }
+  {
+    state_number i;
+
+    for (i = 0; i < nstates; i++)
+      if (conflicts[i])
+        {
+          src_total += count_sr_conflicts (states[i]);
+          rrc_total += count_rr_conflicts (states[i], true);
+        }
+  }
+
+  if (! glr_parser && expected_rr_conflicts != -1)
+    {
+      complain (Wother, _("%%expect-rr applies only to GLR parsers"));
+      expected_rr_conflicts = -1;
+    }
 
-  src_ok = src_total == (expected_conflicts == -1 ? 0 : expected_conflicts);
+  src_expected = expected_sr_conflicts == -1 ? 0 : expected_sr_conflicts;
+  rrc_expected = expected_rr_conflicts == -1 ? 0 : expected_rr_conflicts;
+  src_ok = src_total == src_expected;
+  rrc_ok = rrc_total == rrc_expected;
 
-  /* If there are no RR conflicts, and as many SR conflicts as
+  /* If there are as many RR conflicts and SR conflicts as
      expected, then there is nothing to report.  */
-  if (!rrc_total && src_ok)
+  if (rrc_ok & src_ok)
     return;
 
   /* Report the total number of conflicts on STDERR.  */
-  if (yacc_flag)
+  if (expected_sr_conflicts == -1 && expected_rr_conflicts == -1)
     {
-      /* If invoked with `--yacc', use the output format specified by
-	 POSIX.  */
-      fprintf (stderr, _("conflicts: "));
-      if (src_total > 0)
-	fprintf (stderr, _(" %d shift/reduce"), src_total);
-      if (src_total > 0 && rrc_total > 0)
-	fprintf (stderr, ",");
-      if (rrc_total > 0)
-	fprintf (stderr, _(" %d reduce/reduce"), rrc_total);
-      putc ('\n', stderr);
+      if (!(warnings_flag & Wconflicts_sr))
+        src_total = 0;
+      if (!(warnings_flag & Wconflicts_rr))
+        rrc_total = 0;
     }
-  else
+  if (src_total | rrc_total)
     {
-      fprintf (stderr, _("%s contains "), infile);
-      fputs (conflict_report (src_total, rrc_total), stderr);
+      if (expected_sr_conflicts == -1 && expected_rr_conflicts == -1)
+        set_warning_issued ();
+      if (! yacc_flag)
+        fprintf (stderr, "%s: ", current_file);
+      conflict_report (stderr, src_total, rrc_total);
     }
 
-  if (expected_conflicts != -1 && !src_ok)
-    {
-      complain_message_count++;
-      fprintf (stderr, ngettext ("expected %d shift/reduce conflict\n",
-				 "expected %d shift/reduce conflicts\n",
-				 expected_conflicts),
-	       expected_conflicts);
-    }
-}
-
-
-void
-print_reductions (FILE *out, int state)
-{
-  int i;
-  int j;
-  int symbol;
-  int m;
-  int n;
-  shifts *shiftp;
-  errs *errp;
-  int nodefault = 0;
-
-  for (i = 0; i < tokensetsize; i++)
-    shiftset[i] = 0;
-
-  shiftp = state_table[state].shift_table;
-  if (shiftp)
-    for (i = 0; i < shiftp->nshifts; i++)
-      {
-	if (!shiftp->shifts[i])
-	  continue;
-	symbol = state_table[shiftp->shifts[i]].accessing_symbol;
-	if (ISVAR (symbol))
-	  break;
-	/* if this state has a shift for the error token,
-	   don't use a default rule.  */
-	if (symbol == error_token_number)
-	  nodefault = 1;
-	SETBIT (shiftset, symbol);
-      }
-
-  errp = err_table[state];
-  if (errp)
-    for (i = 0; i < errp->nerrs; i++)
-      if (errp->errs[i])
-	SETBIT (shiftset, errp->errs[i]);
-
-  m = state_table[state].lookaheads;
-  n = state_table[state + 1].lookaheads;
-
-  if (n - m == 1 && !nodefault)
-    {
-      int k;
-      int default_rule = LAruleno[m];
-
-      for (k = 0; k < tokensetsize; ++k)
-	lookaheadset[k] = LA (m)[k] & shiftset[k];
-
-      for (i = 0; i < ntokens; i++)
-	if (BITISSET (lookaheadset, i))
-	  fprintf (out, _("    %-4s\t[reduce using rule %d (%s)]\n"),
-		   tags[i], default_rule,
-		   tags[rule_table[default_rule].lhs]);
-
-      fprintf (out, _("    $default\treduce using rule %d (%s)\n\n"),
-	       default_rule, tags[rule_table[default_rule].lhs]);
-    }
-  else if (n - m >= 1)
+  if (expected_sr_conflicts != -1 || expected_rr_conflicts != -1)
     {
-      int k;
-
-      int cmax = 0;
-      int default_LA = -1;
-      int default_rule = 0;
-
-      if (!nodefault)
-	for (i = m; i < n; i++)
-	  {
-	    int count = 0;
-
-	    for (k = 0; k < tokensetsize; ++k)
-	      lookaheadset[k] = LA (i)[k] & ~shiftset[k];
-
-	    for (j = 0; j < ntokens; j++)
-	      if (BITISSET (lookaheadset, j))
-		count++;
-
-	    if (count > cmax)
-	      {
-		cmax = count;
-		default_LA = i;
-		default_rule = LAruleno[i];
-	      }
-
-	    for (k = 0; k < tokensetsize; ++k)
-	      shiftset[k] |= lookaheadset[k];
-	  }
-
-      for (i = 0; i < tokensetsize; i++)
-	shiftset[i] = 0;
-
-      if (shiftp)
-	for (i = 0; i < shiftp->nshifts; i++)
-	  {
-	    if (!shiftp->shifts[i])
-	      continue;
-	    symbol = state_table[shiftp->shifts[i]].accessing_symbol;
-	    if (ISVAR (symbol))
-	      break;
-	    SETBIT (shiftset, symbol);
-	  }
-
-      for (i = 0; i < ntokens; i++)
-	{
-	  int defaulted = 0;
-	  int count = BITISSET (shiftset, i);
-
-	  for (j = m; j < n; j++)
-	    {
-	      if (BITISSET (LA (m), j))
-		{
-		  if (count == 0)
-		    {
-		      if (j != default_LA)
-			fprintf (out,
-				 _("    %-4s\treduce using rule %d (%s)\n"),
-				 tags[i],
-				 LAruleno[j],
-				 tags[rule_table[LAruleno[j]].lhs]);
-		      else
-			defaulted = 1;
-
-		      count++;
-		    }
-		  else
-		    {
-		      if (defaulted)
-			fprintf (out,
-				 _("    %-4s\treduce using rule %d (%s)\n"),
-				 tags[i],
-				 LAruleno[default_LA],
-				 tags[rule_table[LAruleno[default_LA]].lhs]);
-		      defaulted = 0;
-		      fprintf (out,
-			       _("    %-4s\t[reduce using rule %d (%s)]\n"),
-			       tags[i],
-			       LAruleno[j],
-			       tags[rule_table[LAruleno[j]].lhs]);
-		    }
-		}
-	    }
-	}
-
-      if (default_LA >= 0)
-	fprintf (out, _("    $default\treduce using rule %d (%s)\n"),
-		 default_rule, tags[rule_table[default_rule].lhs]);
+      if (! src_ok)
+        complain (complaint, ngettext ("expected %d shift/reduce conflict",
+                                       "expected %d shift/reduce conflicts",
+                                       src_expected),
+                  src_expected);
+      if (! rrc_ok)
+        complain (complaint, ngettext ("expected %d reduce/reduce conflict",
+                                       "expected %d reduce/reduce conflicts",
+                                       rrc_expected),
+                  rrc_expected);
     }
 }
 
 
 void
-free_conflicts (void)
+conflicts_free (void)
 {
-  XFREE (conflicts);
-  XFREE (shiftset);
-  XFREE (lookaheadset);
+  free (conflicts);
+  bitset_free (shift_set);
+  bitset_free (lookahead_set);
+  obstack_free (&solved_conflicts_obstack, NULL);
+  obstack_free (&solved_conflicts_xml_obstack, NULL);
 }