* src/system.h (LIST_FREE, shortcpy): New.

[bison.git] / src / lalr.c

diff --git a/src/lalr.c b/src/lalr.c
index ce076d4d3c887b04f6fc082de49ea9a29b50a5ac..42cd05ef938f287ae97866fccd98c1c7a02eb29d 100644 (file)
--- a/src/lalr.c
+++ b/src/lalr.c
@@ -1,5 +1,5 @@
 /* Compute look-ahead criteria for bison,
-   Copyright 1984, 1986, 1989, 2000 Free Software Foundation, Inc.
+   Copyright 1984, 1986, 1989, 2000, 2001  Free Software Foundation, Inc.
 
    This file is part of Bison, the GNU Compiler Compiler.
 
@@ -48,9 +48,13 @@ short *to_state;
 extern void berror PARAMS ((const char *));
 
 static int infinity;
-static int maxrhs;
 static int ngotos;
-static unsigned *F;
+
+/* And for the famous F variable, which named is so descriptive that a
+   comment is hardly needed.  <grin>.  */
+static unsigned *F = NULL;
+#define F(Rule)  (F + (Rule) * tokensetsize)
+
 static short **includes;
 static shorts **lookback;
 static short **R;
@@ -74,8 +78,8 @@ traverse (int i)
   VERTICES[++top] = i;
   INDEX[i] = height = top;
 
-  base = F + i * tokensetsize;
-  fp3 = base + tokensetsize;
+  base = F (i);
+  fp3 = F (i + 1);
 
   rp = R[i];
   if (rp)
@@ -89,7 +93,7 @@ traverse (int i)
            INDEX[i] = INDEX[j];
 
          fp1 = base;
-         fp2 = F + j * tokensetsize;
+         fp2 = F (j);
 
          while (fp1 < fp3)
            *fp1++ |= *fp2++;
@@ -107,7 +111,7 @@ traverse (int i)
            break;
 
          fp1 = base;
-         fp2 = F + j * tokensetsize;
+         fp2 = F (j);
 
          while (fp1 < fp3)
            *fp2++ = *fp1++;
@@ -132,15 +136,18 @@ digraph (short **relation)
     INDEX[i] = 0;
 
   for (i = 0; i < ngotos; i++)
-    {
-      if (INDEX[i] == 0 && R[i])
-       traverse (i);
-    }
+    if (INDEX[i] == 0 && R[i])
+      traverse (i);
 
   XFREE (INDEX);
   XFREE (VERTICES);
 }
 
+
+/*--------------------.
+| Build STATE_TABLE.  |
+`--------------------*/
+
 static void
 set_state_table (void)
 {
@@ -205,8 +212,9 @@ set_state_table (void)
 }
 
 
-static void
-set_maxrhs (void)
+/* Return the size of the longest ride hand side of the rules. */
+static size_t
+maxrhs (void)
 {
   short *itemp;
   int length;
@@ -228,7 +236,7 @@ set_maxrhs (void)
        }
     }
 
-  maxrhs = max;
+  return max;
 }
 
 
@@ -426,10 +434,7 @@ initialize_F (void)
   digraph (reads);
 
   for (i = 0; i < ngotos; i++)
-    {
-      if (reads[i])
-       XFREE (reads[i]);
-    }
+    XFREE (reads[i]);
 
   XFREE (reads);
   XFREE (edge);
@@ -542,7 +547,7 @@ build_relations (void)
 
   includes = XCALLOC (short *, ngotos);
   edge = XCALLOC (short, ngotos + 1);
-  states = XCALLOC (short, maxrhs + 1);
+  states = XCALLOC (short, maxrhs () + 1);
 
   for (i = 0; i < ngotos; i++)
     {
@@ -556,7 +561,7 @@ build_relations (void)
          states[0] = state1;
          stateno = state1;
 
-         for (rp = ritem + rrhs[*rulep]; *rp > 0; rp++)
+         for (rp = ritem + rule_table[*rulep].rhs; *rp > 0; rp++)
            {
              symbol2 = *rp;
              sp = state_table[stateno].shift_table;
@@ -625,10 +630,7 @@ compute_FOLLOWS (void)
   digraph (includes);
 
   for (i = 0; i < ngotos; i++)
-    {
-      if (includes[i])
-       XFREE (includes[i]);
-    }
+    XFREE (includes[i]);
 
   XFREE (includes);
 }
@@ -638,38 +640,20 @@ static void
 compute_lookaheads (void)
 {
   int i;
-  int n;
-  unsigned *fp1;
-  unsigned *fp2;
-  unsigned *fp3;
   shorts *sp;
-  unsigned *rowp;
-  shorts *sptmp;               /* JF */
 
-  rowp = LA;
   for (i = 0; i < state_table[nstates].lookaheads; i++)
-    {
-      fp3 = rowp + tokensetsize;
-      for (sp = lookback[i]; sp; sp = sp->next)
-       {
-         fp1 = rowp;
-         fp2 = F + tokensetsize * sp->value;
-         while (fp1 < fp3)
-           *fp1++ |= *fp2++;
-       }
-
-      rowp = fp3;
-    }
+    for (sp = lookback[i]; sp; sp = sp->next)
+      {
+       unsigned *fp1 = LA (i);
+       unsigned *fp2 = F (sp->value);
+       while (fp1 < LA (i + 1))
+         *fp1++ |= *fp2++;
+      }
 
+  /* Free LOOKBACK. */
   for (i = 0; i < state_table[nstates].lookaheads; i++)
-    {
-      /* JF removed ref to freed storage */
-      for (sp = lookback[i]; sp; sp = sptmp)
-       {
-         sptmp = sp->next;
-         XFREE (sp);
-       }
-    }
+    LIST_FREE (shorts, lookback[i]);
 
   XFREE (lookback);
   XFREE (F);
@@ -682,7 +666,6 @@ lalr (void)
   tokensetsize = WORDSIZE (ntokens);
 
   set_state_table ();
-  set_maxrhs ();
   initialize_LA ();
   set_goto_map ();
   initialize_F ();