* src/derives.c (print_derives): Display the ruleno.

* src/lalr.c (initialize_F, transpose): Better variable locality
to improve readability.
Avoid variables used as mere abbreviations.

ChangeLog

@@ -1,3 +1,10 @@
+2001-12-05  Akim Demaille  <akim@epita.fr>
+
+	* src/derives.c (print_derives): Display the ruleno.
+	* src/lalr.c (initialize_F, transpose): Better variable locality
+	to improve readability.
+	Avoid variables used as mere abbreviations.
+
 2001-12-05  Akim Demaille  <akim@epita.fr>
 
 	* src/lalr.c (traverse): Use arrays instead of pointers.

src/derives.c

@@ -19,11 +19,6 @@
    Boston, MA 02111-1307, USA.  */
 
 
-/* set_derives finds, for each variable (nonterminal), which rules can
-   derive it.  It sets up the value of derives so that derives[i -
-   ntokens] points to a vector of rule numbers, terminated with -1.
-   */
-
 #include "system.h"
 #include "getargs.h"
 #include "types.h"
@@ -31,8 +26,7 @@
 #include "gram.h"
 #include "derives.h"
 
-short **derives;
-
+short **derives = NULL;
 
 static void
 print_derives (void)
@@ -51,7 +45,7 @@ print_derives (void)
 	  fprintf (stderr, "\t\t%d:", *sp);
 	  for (rhsp = ritem + rule_table[*sp].rhs; *rhsp > 0; ++rhsp)
 	    fprintf (stderr, " %s", tags[*rhsp]);
-	  fputc ('\n', stderr);
+	  fprintf (stderr, " (rule %d)\n", -*rhsp);
 	}
     }
 

src/derives.h

@@ -1,5 +1,5 @@
 /* Match rules with nonterminals for bison,
-   Copyright 1984, 1989, 2000 Free Software Foundation, Inc.
+   Copyright 1984, 1989, 2000, 2001 Free Software Foundation, Inc.
 
    This file is part of Bison, the GNU Compiler Compiler.
 
@@ -21,12 +21,11 @@
 #ifndef DERIVES_H_
 # define DERIVES_H_
 
+/* DERIVES[SYMBOL - NTOKENS] points to a vector of the number of the
+   rules that SYMBOL derives, terminated with -1.  */
 extern short **derives;
 
-/* set_derives finds, for each variable (nonterminal), which rules can
-   derive it.  It sets up the value of derives so that derives[i -
-   ntokens] points to a vector of rule numbers, terminated with -1.
-   */
+/* Compute DERIVES.  */
 
 void set_derives PARAMS((void));
 void free_derives PARAMS((void));

src/lalr.c

@@ -358,14 +358,11 @@ initialize_F (void)
 {
   int i;
   int j;
-  int k;
-  shifts *sp;
   short *edge;
   unsigned *rowp;
   short *rp;
   short **reads;
   int nedges;
-  int stateno;
   int symbol;
   int nwords;
 
@@ -379,14 +376,12 @@ initialize_F (void)
   rowp = F;
   for (i = 0; i < ngotos; i++)
     {
-      stateno = to_state[i];
-      sp = state_table[stateno].shift_table;
+      int stateno = to_state[i];
+      shifts *sp = state_table[stateno].shift_table;
 
       if (sp)
 	{
-	  k = sp->nshifts;
-
-	  for (j = 0; j < k; j++)
+	  for (j = 0; j < sp->nshifts; j++)
 	    {
 	      symbol = state_table[sp->shifts[j]].accessing_symbol;
 	      if (ISVAR (symbol))
@@ -394,7 +389,7 @@ initialize_F (void)
 	      SETBIT (rowp, symbol);
 	    }
 
-	  for (; j < k; j++)
+	  for (; j < sp->nshifts; j++)
 	    {
 	      symbol = state_table[sp->shifts[j]].accessing_symbol;
 	      if (nullable[symbol])
@@ -460,15 +455,13 @@ transpose (short **R_arg, int n)
   short **new_R;
   short **temp_R;
   short *nedges;
-  short *sp;
   int i;
-  int k;
 
   nedges = XCALLOC (short, n);
 
   for (i = 0; i < n; i++)
     {
-      sp = R_arg[i];
+      short *sp = R_arg[i];
       if (sp)
 	{
 	  while (*sp >= 0)
@@ -480,27 +473,22 @@ transpose (short **R_arg, int n)
   temp_R = XCALLOC (short *, n);
 
   for (i = 0; i < n; i++)
-    {
-      k = nedges[i];
-      if (k > 0)
-	{
-	  sp = XCALLOC (short, k + 1);
-	  new_R[i] = sp;
-	  temp_R[i] = sp;
-	  sp[k] = -1;
-	}
-    }
+    if (nedges[i] > 0)
+      {
+	short *sp = XCALLOC (short, nedges[i] + 1);
+	new_R[i] = sp;
+	temp_R[i] = sp;
+	sp[nedges[i]] = -1;
+      }
 
   XFREE (nedges);
 
   for (i = 0; i < n; i++)
     {
-      sp = R_arg[i];
+      short *sp = R_arg[i];
       if (sp)
-	{
-	  while (*sp >= 0)
-	    *temp_R[*sp++]++ = i;
-	}
+	while (*sp >= 0)
+	  *temp_R[*sp++]++ = i;
     }
 
   XFREE (temp_R);
@@ -514,18 +502,13 @@ build_relations (void)
 {
   int i;
   int j;
-  int k;
   short *rulep;
   short *rp;
-  shifts *sp;
-  int length;
   int nedges;
   int done;
   int state1;
   int stateno;
   int symbol1;
-  int symbol2;
-  short *shortp;
   short *edge;
   short *states;
   short **new_includes;
@@ -542,17 +525,16 @@ build_relations (void)
 
       for (rulep = derives[symbol1]; *rulep > 0; rulep++)
 	{
-	  length = 1;
+	  int length = 1;
 	  states[0] = state1;
 	  stateno = state1;
 
 	  for (rp = ritem + rule_table[*rulep].rhs; *rp > 0; rp++)
 	    {
-	      symbol2 = *rp;
-	      sp = state_table[stateno].shift_table;
-	      k = sp->nshifts;
+	      int symbol2 = *rp;
+	      shifts *sp = state_table[stateno].shift_table;
 
-	      for (j = 0; j < k; j++)
+	      for (j = 0; j < sp->nshifts; j++)
 		{
 		  stateno = sp->shifts[j];
 		  if (state_table[stateno].accessing_symbol == symbol2)
@@ -584,19 +566,17 @@ build_relations (void)
 
       if (nedges)
 	{
-	  includes[i] = shortp = XCALLOC (short, nedges + 1);
+	  includes[i] = XCALLOC (short, nedges + 1);
 	  for (j = 0; j < nedges; j++)
-	    shortp[j] = edge[j];
-	  shortp[nedges] = -1;
+	    includes[i][j] = edge[j];
+	  includes[i][nedges] = -1;
 	}
     }
 
   new_includes = transpose (includes, ngotos);
 
   for (i = 0; i < ngotos; i++)
-    if (includes[i])
-      XFREE (includes[i]);
-
+    XFREE (includes[i]);
   XFREE (includes);
 
   includes = new_includes;