* src/conflicts.c (flush_shift): Also adjust lookaheadset.

[bison.git] / src / conflicts.c

diff --git a/src/conflicts.c b/src/conflicts.c
index a9bf9519c3bd011d64470dbbd8583282a61fa233..cbd002d513114defbdb2c7d1da80c4e37fb63aa0 100644 (file)
--- a/src/conflicts.c
+++ b/src/conflicts.c
@@ -29,7 +29,6 @@
 #include "reader.h"
 #include "LR0.h"
 
 #include "reader.h"
 #include "LR0.h"
 

-errs **err_table = NULL;

 /* -1 stands for not specified. */
 int expected_conflicts = -1;
 static char *conflicts = NULL;
 /* -1 stands for not specified. */
 int expected_conflicts = -1;
 static char *conflicts = NULL;


@@ -41,10 +40,11 @@ static unsigned *lookaheadset = NULL;
 static inline void
 log_resolution (int state, int LAno, int token, char *resolution)
 {
 static inline void
 log_resolution (int state, int LAno, int token, char *resolution)
 {

-  obstack_fgrow4 (&output_obstack,
-                 _("\
+  if (verbose_flag)
+    obstack_fgrow4 (&output_obstack,
+                   _("\

 Conflict in state %d between rule %d and token %s resolved as %s.\n"),
 Conflict in state %d between rule %d and token %s resolved as %s.\n"),

-                 state, LAruleno[LAno], tags[token], resolution);
+                   state, LAruleno[LAno], tags[token], resolution);

 }
 
 
 }
 
 


@@ -57,13 +57,26 @@ Conflict in state %d between rule %d and token %s resolved as %s.\n"),
 static void
 flush_shift (int state, int token)
 {
 static void
 flush_shift (int state, int token)
 {

-  shifts *shiftp = state_table[state].shift_table;
+  shifts *shiftp = state_table[state]->shifts;

   int i;
 
   int i;
 

-  if (shiftp)
-    for (i = 0; i < shiftp->nshifts; i++)
-      if (!SHIFT_IS_DISABLED (shiftp, i) && SHIFT_SYMBOL (shiftp, i) == token)
-       SHIFT_DISABLE (shiftp, i);
+  RESETBIT (lookaheadset, token);
+  for (i = 0; i < shiftp->nshifts; i++)
+    if (!SHIFT_IS_DISABLED (shiftp, i) && SHIFT_SYMBOL (shiftp, i) == token)
+      SHIFT_DISABLE (shiftp, 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.                                             |
+`-------------------------------------------------------------------*/
+
+static void
+flush_reduce (int lookahead, int token)
+{
+  RESETBIT (LA (lookahead), token);

 }
 
 
 }
 
 


@@ -75,88 +88,66 @@ flush_shift (int state, int token)
 `------------------------------------------------------------------*/
 
 static void
 `------------------------------------------------------------------*/
 
 static void

-resolve_sr_conflict (int state, int lookaheadnum)
+resolve_sr_conflict (int state, int lookahead)

 {
   int i;
   /* find the rule to reduce by to get precedence of reduction  */
 {
   int i;
   /* find the rule to reduce by to get precedence of reduction  */

-  int redprec = rule_table[LAruleno[lookaheadnum]].prec;
+  int redprec = rule_table[LAruleno[lookahead]].prec;

   errs *errp = ERRS_ALLOC (ntokens + 1);
   short *errtokens = errp->errs;
 
   for (i = 0; i < ntokens; i++)
   errs *errp = ERRS_ALLOC (ntokens + 1);
   short *errtokens = errp->errs;
 
   for (i = 0; i < ntokens; i++)

-    {
-      if (BITISSET (LA (lookaheadnum), i)
-         && BITISSET (lookaheadset, i)
-         && sprec[i])
+    if (BITISSET (LA (lookahead), i)
+       && BITISSET (lookaheadset, i)
+       && sprec[i])
+      {

        /* Shift-reduce conflict occurs for token number i
           and it has a precedence.
           The precedence of shifting is that of token 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"));
-             /* flush the shift for this token */
-             RESETBIT (lookaheadset, i);
-             flush_shift (state, i);
-           }
-         else if (sprec[i] > redprec)
-           {
-             log_resolution (state, lookaheadnum, i, _("shift"));
-             /* flush the reduce for this token */
-             RESETBIT (LA (lookaheadnum), i);
-           }
-         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;
+       if (sprec[i] < redprec)
+         {
+           log_resolution (state, lookahead, i, _("reduce"));
+           flush_shift (state, i);
+         }
+       else if (sprec[i] > redprec)
+         {
+           log_resolution (state, lookahead, i, _("shift"));
+           flush_reduce (lookahead, i);
+         }
+       else
+         /* Matching precedence levels.
+            For left association, keep only the reduction.
+            For right association, keep only the shift.
+            For nonassociation, keep neither.  */

 
 

-               case left_assoc:
-                 log_resolution (state, lookaheadnum, i, _("reduce"));
-                 break;
+         switch (sassoc[i])
+           {
+           case right_assoc:
+             log_resolution (state, lookahead, i, _("shift"));
+             flush_reduce (lookahead, i);
+             break;

 
 

-               case non_assoc:
-                 log_resolution (state, lookaheadnum, i, _("an error"));
-                 break;
-               }
+           case left_assoc:
+             log_resolution (state, lookahead, i, _("reduce"));
+             flush_shift (state, i);
+             break;

 
 

-             if (sassoc[i] != right_assoc)
-               {
-                 /* flush the shift for this token */
-                 RESETBIT (lookaheadset, i);
-                 flush_shift (state, i);
-               }
-             if (sassoc[i] != left_assoc)
-               {
-                 /* flush the reduce for this token */
-                 RESETBIT (LA (lookaheadnum), i);
-               }
-             if (sassoc[i] == non_assoc)
-               {
-                 /* Record an explicit error for this token.  */
-                 *errtokens++ = i;
-               }
+           case non_assoc:
+             log_resolution (state, lookahead, i, _("an error"));
+             flush_shift (state, i);
+             flush_reduce (lookahead, i);
+             /* Record an explicit error for this token.  */
+             *errtokens++ = i;
+             break;

            }
            }

-       }
-    }
+      }
+

   errp->nerrs = errtokens - errp->errs;
   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;
+  /* Some tokens have been explicitly made errors.  Allocate a
+     permanent errs structure for this state, to record them.  */
+  i = (char *) errtokens - (char *) errp;
+  state_table[state]->errs = ERRS_ALLOC (i + 1);
+  memcpy (state_table[state]->errs, errp, i);

   free (errp);
 }
 
   free (errp);
 }
 


@@ -167,23 +158,22 @@ set_conflicts (int state)
   int i, j;
   shifts *shiftp;
 
   int i, j;
   shifts *shiftp;
 

-  if (state_table[state].consistent)
+  if (state_table[state]->consistent)

     return;
 
   for (i = 0; i < tokensetsize; i++)
     lookaheadset[i] = 0;
 
     return;
 
   for (i = 0; i < tokensetsize; i++)
     lookaheadset[i] = 0;
 

-  shiftp = state_table[state].shift_table;
-  if (shiftp)
-    for (i = 0; i < shiftp->nshifts && SHIFT_IS_SHIFT (shiftp, i); i++)
-      if (!SHIFT_IS_DISABLED (shiftp, i))
-       SETBIT (lookaheadset, SHIFT_SYMBOL (shiftp, i));
+  shiftp = state_table[state]->shifts;
+  for (i = 0; i < shiftp->nshifts && SHIFT_IS_SHIFT (shiftp, i); i++)
+    if (!SHIFT_IS_DISABLED (shiftp, i))
+      SETBIT (lookaheadset, SHIFT_SYMBOL (shiftp, i));

 
   /* Loop over all rules which require lookahead in this state.  First
      check for shift-reduce conflict, and try to resolve using
      precedence */
 
   /* 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;
+  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)
        ++i)
     if (rule_table[LAruleno[i]].prec)
       for (j = 0; j < tokensetsize; ++j)


@@ -196,8 +186,8 @@ set_conflicts (int state)
 
   /* Loop over all rules which require lookahead in this state.  Check
      for conflicts not resolved above.  */
 
   /* 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;
+  for (i = state_table[state]->lookaheads;
+       i < state_table[state + 1]->lookaheads;

        ++i)
     {
       for (j = 0; j < tokensetsize; ++j)
        ++i)
     {
       for (j = 0; j < tokensetsize; ++j)


@@ -218,8 +208,6 @@ solve_conflicts (void)
   shiftset = XCALLOC (unsigned, tokensetsize);
   lookaheadset = XCALLOC (unsigned, tokensetsize);
 
   shiftset = XCALLOC (unsigned, tokensetsize);
   lookaheadset = XCALLOC (unsigned, tokensetsize);
 

-  err_table = XCALLOC (errs *, nstates);
-

   for (i = 0; i < nstates; i++)
     set_conflicts (i);
 }
   for (i = 0; i < nstates; i++)
     set_conflicts (i);
 }


@@ -234,7 +222,7 @@ count_sr_conflicts (int state)
 {
   int i, k;
   int src_count = 0;
 {
   int i, k;
   int src_count = 0;

-  shifts *shiftp = state_table[state].shift_table;
+  shifts *shiftp = state_table[state]->shifts;

 
   if (!shiftp)
     return 0;
 
   if (!shiftp)
     return 0;


@@ -249,8 +237,8 @@ count_sr_conflicts (int state)
     if (!SHIFT_IS_DISABLED (shiftp, i))
       SETBIT (shiftset, SHIFT_SYMBOL (shiftp, i));
 
     if (!SHIFT_IS_DISABLED (shiftp, i))
       SETBIT (shiftset, SHIFT_SYMBOL (shiftp, i));
 

-  for (i = state_table[state].lookaheads;
-       i < state_table[state + 1].lookaheads;
+  for (i = state_table[state]->lookaheads;
+       i < state_table[state + 1]->lookaheads;

        ++i)
     for (k = 0; k < tokensetsize; ++k)
       lookaheadset[k] |= LA (i)[k];
        ++i)
     for (k = 0; k < tokensetsize; ++k)
       lookaheadset[k] |= LA (i)[k];


@@ -276,8 +264,8 @@ count_rr_conflicts (int state)
   int i;
   int rrc_count = 0;
 
   int i;
   int rrc_count = 0;
 

-  int m = state_table[state].lookaheads;
-  int n = state_table[state + 1].lookaheads;
+  int m = state_table[state]->lookaheads;
+  int n = state_table[state + 1]->lookaheads;

 
   if (n - m < 2)
     return 0;
 
   if (n - m < 2)
     return 0;


@@ -435,26 +423,25 @@ print_reductions (FILE *out, int state)
   for (i = 0; i < tokensetsize; i++)
     shiftset[i] = 0;
 
   for (i = 0; i < tokensetsize; i++)
     shiftset[i] = 0;
 

-  shiftp = state_table[state].shift_table;
-  if (shiftp)
-    for (i = 0; i < shiftp->nshifts && SHIFT_IS_SHIFT (shiftp, i); i++)
-      if (!SHIFT_IS_DISABLED (shiftp, i))
-       {
-         /* if this state has a shift for the error token, don't use a
-            default rule.  */
-         if (SHIFT_IS_ERROR (shiftp, i))
-           nodefault = 1;
-         SETBIT (shiftset, SHIFT_SYMBOL (shiftp, i));
-       }
+  shiftp = state_table[state]->shifts;
+  for (i = 0; i < shiftp->nshifts && SHIFT_IS_SHIFT (shiftp, i); i++)
+    if (!SHIFT_IS_DISABLED (shiftp, i))
+      {
+       /* if this state has a shift for the error token, don't use a
+          default rule.  */
+       if (SHIFT_IS_ERROR (shiftp, i))
+         nodefault = 1;
+       SETBIT (shiftset, SHIFT_SYMBOL (shiftp, i));
+      }

 
 

-  errp = err_table[state];
+  errp = state_table[state]->errs;

   if (errp)
     for (i = 0; i < errp->nerrs; i++)
       if (errp->errs[i])
        SETBIT (shiftset, errp->errs[i]);
 
   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;
+  m = state_table[state]->lookaheads;
+  n = state_table[state + 1]->lookaheads;

 
   if (n - m == 1 && !nodefault)
     {
 
   if (n - m == 1 && !nodefault)
     {


@@ -507,10 +494,9 @@ print_reductions (FILE *out, int state)
       for (i = 0; i < tokensetsize; i++)
        shiftset[i] = 0;
 
       for (i = 0; i < tokensetsize; i++)
        shiftset[i] = 0;
 

-      if (shiftp)
-       for (i = 0; i < shiftp->nshifts && SHIFT_IS_SHIFT (shiftp, i); i++)
-         if (!SHIFT_IS_DISABLED (shiftp, i))
-           SETBIT (shiftset, SHIFT_SYMBOL (shiftp, i));
+      for (i = 0; i < shiftp->nshifts && SHIFT_IS_SHIFT (shiftp, i); i++)
+       if (!SHIFT_IS_DISABLED (shiftp, i))
+         SETBIT (shiftset, SHIFT_SYMBOL (shiftp, i));

 
       for (i = 0; i < ntokens; i++)
        {
 
       for (i = 0; i < ntokens; i++)
        {