Use bitset operations when possible, not loops over bits.

[bison.git] / src / conflicts.c

diff --git a/src/conflicts.c b/src/conflicts.c
index 746fcb50cd6f3fc70e6075e5ef88aed1dc124aa4..e08256a161b8b9e8ec6eab7a67afebe3e0660da6 100644 (file)
--- a/src/conflicts.c
+++ b/src/conflicts.c
@@ -1,5 +1,5 @@
 /* Find and resolve or report look-ahead conflicts for bison,
-   Copyright 1984, 1989, 1992, 2000, 2001 Free Software Foundation, Inc.
+   Copyright 1984, 1989, 1992, 2000, 2001, 2002 Free Software Foundation, Inc.
 
    This file is part of Bison, the GNU Compiler Compiler.
 
@@ -19,6 +19,7 @@
    02111-1307, USA.  */
 
 #include "system.h"
+#include "bitset.h"
 #include "complain.h"
 #include "getargs.h"
 #include "symtab.h"
@@ -34,8 +35,8 @@
 int expected_conflicts = -1;
 static char *conflicts = NULL;
 
-static unsigned *shiftset = NULL;
-static unsigned *lookaheadset = NULL;
+static bitset shiftset;
+static bitset lookaheadset;
 \f
 
 static inline void
@@ -62,7 +63,7 @@ flush_shift (state_t *state, int token)
   shifts *shiftp = state->shifts;
   int i;
 
-  RESETBIT (lookaheadset, token);
+  bitset_reset (lookaheadset, token);
   for (i = 0; i < shiftp->nshifts; i++)
     if (!SHIFT_IS_DISABLED (shiftp, i) && SHIFT_SYMBOL (shiftp, i) == token)
       SHIFT_DISABLE (shiftp, i);
@@ -78,7 +79,7 @@ flush_shift (state_t *state, int token)
 static void
 flush_reduce (int lookahead, int token)
 {
-  RESETBIT (LA (lookahead), token);
+  bitset_reset (LA[lookahead], token);
 }
 
 
@@ -99,8 +100,8 @@ resolve_sr_conflict (state_t *state, int lookahead)
   errp->nerrs = 0;
 
   for (i = 0; i < ntokens; i++)
-    if (BITISSET (LA (lookahead), i)
-       && BITISSET (lookaheadset, i)
+    if (bitset_test (LA[lookahead], i)
+       && bitset_test (lookaheadset, i)
        && symbols[i]->prec)
       {
        /* Shift-reduce conflict occurs for token number i
@@ -160,21 +161,21 @@ set_conflicts (state_t *state)
   if (state->consistent)
     return;
 
-  for (i = 0; i < tokensetsize; i++)
-    lookaheadset[i] = 0;
+  bitset_zero (lookaheadset);
 
   shiftp = 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));
+      bitset_set (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 */
   for (i = 0; i < state->nlookaheads; ++i)
     if (rules[LAruleno[state->lookaheadsp + i]].prec)
-      for (j = 0; j < tokensetsize; ++j)
-       if (LA (state->lookaheadsp + i)[j] & lookaheadset[j])
+      for (j = 0; j < ntokens; ++j)
+       if (bitset_test (LA[state->lookaheadsp + i], j)
+           && bitset_test (lookaheadset, j))
          {
            resolve_sr_conflict (state, state->lookaheadsp + i);
            break;
@@ -185,23 +186,26 @@ set_conflicts (state_t *state)
      for conflicts not resolved above.  */
   for (i = 0; i < state->nlookaheads; ++i)
     {
-      for (j = 0; j < tokensetsize; ++j)
-       if (LA (state->lookaheadsp + i)[j] & lookaheadset[j])
+      /* FIXME: Here, I need something like `bitset_disjoint_p'. */
+      for (j = 0; j < ntokens; ++j)
+       if (bitset_test (LA[state->lookaheadsp + i], j)
+           && bitset_test (lookaheadset, j))
          conflicts[state->number] = 1;
 
-      for (j = 0; j < tokensetsize; ++j)
-       lookaheadset[j] |= LA (state->lookaheadsp + i)[j];
+      bitset_or (lookaheadset, lookaheadset, LA[state->lookaheadsp + i]);
     }
 }
 
 void
 solve_conflicts (void)
 {
-  int i;
+  size_t i;
 
   conflicts = XCALLOC (char, nstates);
-  shiftset = XCALLOC (unsigned, tokensetsize);
-  lookaheadset = XCALLOC (unsigned, tokensetsize);
+  shiftset = bitset_create (ntokens, BITSET_FIXED);
+  bitset_zero (shiftset);
+  lookaheadset = bitset_create (ntokens, BITSET_FIXED);
+  bitset_zero (lookaheadset);
 
   for (i = 0; i < nstates; i++)
     set_conflicts (states[i]);
@@ -215,32 +219,27 @@ solve_conflicts (void)
 static int
 count_sr_conflicts (state_t *state)
 {
-  int i, k;
+  int i;
   int src_count = 0;
   shifts *shiftp = state->shifts;
 
   if (!shiftp)
     return 0;
 
-  for (i = 0; i < tokensetsize; i++)
-    {
-      shiftset[i] = 0;
-      lookaheadset[i] = 0;
-    }
+  bitset_zero (lookaheadset);
+  bitset_zero (shiftset);
 
   for (i = 0; i < shiftp->nshifts && SHIFT_IS_SHIFT (shiftp, i); i++)
     if (!SHIFT_IS_DISABLED (shiftp, i))
-      SETBIT (shiftset, SHIFT_SYMBOL (shiftp, i));
+      bitset_set (shiftset, SHIFT_SYMBOL (shiftp, i));
 
   for (i = 0; i < state->nlookaheads; ++i)
-    for (k = 0; k < tokensetsize; ++k)
-      lookaheadset[k] |= LA (state->lookaheadsp + i)[k];
+    bitset_or (lookaheadset, lookaheadset, LA[state->lookaheadsp + i]);
 
-  for (k = 0; k < tokensetsize; ++k)
-    lookaheadset[k] &= shiftset[k];
+  bitset_and (lookaheadset, lookaheadset, shiftset);
 
   for (i = 0; i < ntokens; i++)
-    if (BITISSET (lookaheadset, i))
+    if (bitset_test (lookaheadset, i))
       src_count++;
 
   return src_count;
@@ -265,7 +264,7 @@ count_rr_conflicts (state_t *state)
       int count = 0;
       int j;
       for (j = 0; j < state->nlookaheads; ++j)
-       if (BITISSET (LA (state->lookaheadsp), state->lookaheadsp + j))
+       if (bitset_test (LA[state->lookaheadsp + j], i))
          count++;
 
       if (count >= 2)
@@ -322,7 +321,7 @@ void
 conflicts_output (FILE *out)
 {
   bool printed_sth = FALSE;
-  int i;
+  size_t i;
   for (i = 0; i < nstates; i++)
     if (conflicts[i])
       {
@@ -343,7 +342,7 @@ conflicts_output (FILE *out)
 void
 conflicts_print (void)
 {
-  int i;
+  size_t 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
@@ -403,6 +402,6 @@ void
 free_conflicts (void)
 {
   XFREE (conflicts);
-  XFREE (shiftset);
-  XFREE (lookaheadset);
+  bitset_free (shiftset);
+  bitset_free (lookaheadset);
 }