* src/scan-gram.l: Complete the scanner with the missing patterns

[bison.git] / src / conflicts.c

diff --git a/src/conflicts.c b/src/conflicts.c
index 0ba2e5ac4315ec8953341395a4d188842810cd5d..e09b6d8772b6796b459417d57452d55d77973f57 100644 (file)
--- a/src/conflicts.c
+++ b/src/conflicts.c
@@ -48,12 +48,17 @@ enum conflict_resolution_e
     reduce_resolution,
     left_resolution,
     right_resolution,
-    nonassoc_resolution,
+    nonassoc_resolution
   };
 
 
+/*----------------------------------------------------------------.
+| Explain how an SR conflict between TOKEN and RULE was resolved: |
+| RESOLUTION.                                                     |
+`----------------------------------------------------------------*/
+
 static inline void
-log_resolution (int lookahead, int token,
+log_resolution (rule_t *rule, int token,
                enum conflict_resolution_e resolution)
 {
   if (report_flag & report_solved_conflicts)
@@ -66,7 +71,7 @@ log_resolution (int lookahead, int token,
          obstack_fgrow2 (&solved_conflicts_obstack,
                          _("\
     Conflict between rule %d and token %s resolved as shift"),
-                         LArule[lookahead]->number,
+                         rule->number,
                          symbols[token]->tag);
          break;
        case reduce_resolution:
@@ -74,14 +79,14 @@ log_resolution (int lookahead, int token,
          obstack_fgrow2 (&solved_conflicts_obstack,
                          _("\
     Conflict between rule %d and token %s resolved as reduce"),
-                         LArule[lookahead]->number,
+                         rule->number,
                          symbols[token]->tag);
          break;
        case nonassoc_resolution:
          obstack_fgrow2 (&solved_conflicts_obstack,
                          _("\
     Conflict between rule %d and token %s resolved as an error"),
-                         LArule[lookahead]->number,
+                         rule->number,
                          symbols[token]->tag);
          break;
        }
@@ -92,7 +97,7 @@ log_resolution (int lookahead, int token,
        case shift_resolution:
          obstack_fgrow2 (&solved_conflicts_obstack,
                          " (%s < %s)",
-                         LArule[lookahead]->prec->tag,
+                         rule->prec->tag,
                          symbols[token]->tag);
          break;
 
@@ -100,11 +105,11 @@ log_resolution (int lookahead, int token,
          obstack_fgrow2 (&solved_conflicts_obstack,
                          " (%s < %s)",
                          symbols[token]->tag,
-                         LArule[lookahead]->prec->tag);
+                         rule->prec->tag);
          break;
 
        case left_resolution:
-         obstack_printf (&solved_conflicts_obstack,
+         obstack_fgrow1 (&solved_conflicts_obstack,
                          " (%%left %s)",
                          symbols[token]->tag);
          break;
@@ -151,9 +156,9 @@ flush_shift (state_t *state, int token)
 `-------------------------------------------------------------------*/
 
 static void
-flush_reduce (int lookahead, int token)
+flush_reduce (bitset lookaheads, int token)
 {
-  bitset_reset (LA[lookahead], token);
+  bitset_reset (lookaheads, token);
 }
 
 
@@ -162,19 +167,23 @@ flush_reduce (int lookahead, 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.     |
+|                                                                   |
+| LOOKAHEAD is the number of the lookahead bitset to consider.      |
 `------------------------------------------------------------------*/
 
 static void
 resolve_sr_conflict (state_t *state, int lookahead)
 {
   int i;
-  /* find the rule to reduce by to get precedence of reduction  */
-  int redprec = LArule[lookahead]->prec->prec;
+  /* Find the rule to reduce by to get precedence of reduction.  */
+  rule_t *redrule = state->lookaheads_rule[lookahead];
+  int redprec = redrule->prec->prec;
+  bitset lookaheads = state->lookaheads[lookahead];
   errs *errp = errs_new (ntokens + 1);
   errp->nerrs = 0;
 
   for (i = 0; i < ntokens; i++)
-    if (bitset_test (LA[lookahead], i)
+    if (bitset_test (lookaheads, i)
        && bitset_test (lookaheadset, i)
        && symbols[i]->prec)
       {
@@ -183,13 +192,13 @@ resolve_sr_conflict (state_t *state, int lookahead)
           The precedence of shifting is that of token i.  */
        if (symbols[i]->prec < redprec)
          {
-           log_resolution (lookahead, i, reduce_resolution);
+           log_resolution (redrule, i, reduce_resolution);
            flush_shift (state, i);
          }
        else if (symbols[i]->prec > redprec)
          {
-           log_resolution (lookahead, i, shift_resolution);
-           flush_reduce (lookahead, i);
+           log_resolution (redrule, i, shift_resolution);
+           flush_reduce (lookaheads, i);
          }
        else
          /* Matching precedence levels.
@@ -200,22 +209,26 @@ resolve_sr_conflict (state_t *state, int lookahead)
          switch (symbols[i]->assoc)
            {
            case right_assoc:
-             log_resolution (lookahead, i, right_resolution);
-             flush_reduce (lookahead, i);
+             log_resolution (redrule, i, right_resolution);
+             flush_reduce (lookaheads, i);
              break;
 
            case left_assoc:
-             log_resolution (lookahead, i, left_resolution);
+             log_resolution (redrule, i, left_resolution);
              flush_shift (state, i);
              break;
 
            case non_assoc:
-             log_resolution (lookahead, i, nonassoc_resolution);
+             log_resolution (redrule, i, nonassoc_resolution);
              flush_shift (state, i);
-             flush_reduce (lookahead, i);
+             flush_reduce (lookaheads, i);
              /* Record an explicit error for this token.  */
              errp->errs[errp->nerrs++] = i;
              break;
+
+           case undef_assoc:
+             assert (symbols[i]->assoc != undef_assoc);
+             break;
            }
       }
 
@@ -250,13 +263,13 @@ set_conflicts (state_t *state)
 
   /* Loop over all rules which require lookahead in this state.  First
      check for shift-reduce conflict, and try to resolve using
-     precedence */
+     precedence.  */
   for (i = 0; i < state->nlookaheads; ++i)
-    if (LArule[state->lookaheadsp + i]->prec
-       && LArule[state->lookaheadsp + i]->prec->prec
-       && !bitset_disjoint_p (LA[state->lookaheadsp + i], lookaheadset))
+    if (state->lookaheads_rule[i]->prec
+       && state->lookaheads_rule[i]->prec->prec
+       && !bitset_disjoint_p (state->lookaheads[i], lookaheadset))
       {
-       resolve_sr_conflict (state, state->lookaheadsp + i);
+       resolve_sr_conflict (state, i);
        break;
       }
 
@@ -264,10 +277,10 @@ set_conflicts (state_t *state)
      for conflicts not resolved above.  */
   for (i = 0; i < state->nlookaheads; ++i)
     {
-      if (!bitset_disjoint_p (LA[state->lookaheadsp + i], lookaheadset))
+      if (!bitset_disjoint_p (state->lookaheads[i], lookaheadset))
        conflicts[state->number] = 1;
 
-      bitset_or (lookaheadset, lookaheadset, LA[state->lookaheadsp + i]);
+      bitset_or (lookaheadset, lookaheadset, state->lookaheads[i]);
     }
 }
 
@@ -308,7 +321,7 @@ count_sr_conflicts (state_t *state)
       bitset_set (shiftset, SHIFT_SYMBOL (shiftp, i));
 
   for (i = 0; i < state->nlookaheads; ++i)
-    bitset_or (lookaheadset, lookaheadset, LA[state->lookaheadsp + i]);
+    bitset_or (lookaheadset, lookaheadset, state->lookaheads[i]);
 
   bitset_and (lookaheadset, lookaheadset, shiftset);
 
@@ -336,7 +349,7 @@ count_rr_conflicts (state_t *state)
       int count = 0;
       int j;
       for (j = 0; j < state->nlookaheads; ++j)
-       if (bitset_test (LA[state->lookaheadsp + j], i))
+       if (bitset_test (state->lookaheads[j], i))
          count++;
 
       if (count >= 2)