re PR tree-optimization/31183 (ICE in int_cst_value, at tree.c:7684 with -O3 -ftree-loop-linear)

	PR tree-optimization/31183
	* tree-loop-linear.c (gather_interchange_stats, try_interchange_loops): 
	Use double_int instead of unsigned int for representing access_strides.
	* testsuite/gcc.dg/tree-ssa/pr31183.c: New.

From-SVN: r122988

gcc/ChangeLog

+2007-03-16  Sebastian Pop  <sebastian.pop@inria.fr>
+
+	PR tree-optimization/31183
+	* tree-loop-linear.c (gather_interchange_stats, try_interchange_loops): 
+	Use double_int instead of unsigned int for representing access_strides.
+	* testsuite/gcc.dg/tree-ssa/pr31183.c: New.
+
 2007-03-16  Richard Guenther  <rguenther@suse.de>
 
 	PR tree-optimization/31146

gcc/testsuite/gcc.dg/tree-ssa/pr31183.c

+/* { dg-do compile } */ 
+/* { dg-options "-O2 -ftree-loop-linear" } */
+
+int buf[256 * 9];
+int f() 
+{
+  int i, j;
+
+  for (i = 0; i < 256; ++i)
+    for (j = 0; j < 8; ++j)
+      buf[j + 1] = buf[j] + 1;
+
+  return buf[10];
+}

gcc/tree-loop-linear.c

@@ -95,7 +95,7 @@ gather_interchange_stats (VEC (ddr_p, heap) *dependence_relations,
 			  struct loop *first_loop,
 			  unsigned int *dependence_steps, 
 			  unsigned int *nb_deps_not_carried_by_loop, 
-			  unsigned int *access_strides)
+			  double_int *access_strides)
 {
   unsigned int i, j;
   struct data_dependence_relation *ddr;
@@ -103,7 +103,7 @@ gather_interchange_stats (VEC (ddr_p, heap) *dependence_relations,
 
   *dependence_steps = 0;
   *nb_deps_not_carried_by_loop = 0;
-  *access_strides = 0;
+  *access_strides = double_int_zero;
 
   for (i = 0; VEC_iterate (ddr_p, dependence_relations, i, ddr); i++)
     {
@@ -149,6 +149,7 @@ gather_interchange_stats (VEC (ddr_p, heap) *dependence_relations,
 	  tree chrec = DR_ACCESS_FN (dr, it);
 	  tree tstride = evolution_part_in_loop_num (chrec, loop->num);
 	  tree array_size = TYPE_SIZE (TREE_TYPE (ref));
+	  double_int dstride;
 
 	  if (tstride == NULL_TREE
 	      || array_size == NULL_TREE 
@@ -156,8 +157,9 @@ gather_interchange_stats (VEC (ddr_p, heap) *dependence_relations,
 	      || TREE_CODE (array_size) != INTEGER_CST)
 	    continue;
 
-	  (*access_strides) += 
-	    int_cst_value (array_size) * int_cst_value (tstride);
+	  dstride = double_int_mul (tree_to_double_int (array_size), 
+				    tree_to_double_int (tstride));
+	  (*access_strides) = double_int_add (*access_strides, dstride);
 	}
     }
 }
@@ -180,7 +182,7 @@ try_interchange_loops (lambda_trans_matrix trans,
   struct loop *loop_i;
   struct loop *loop_j;
   unsigned int dependence_steps_i, dependence_steps_j;
-  unsigned int access_strides_i, access_strides_j;
+  double_int access_strides_i, access_strides_j;
   unsigned int nb_deps_not_carried_by_i, nb_deps_not_carried_by_j;
   struct data_dependence_relation *ddr;
 
@@ -225,7 +227,7 @@ try_interchange_loops (lambda_trans_matrix trans,
 	*/
 	if (dependence_steps_i < dependence_steps_j 
 	    || nb_deps_not_carried_by_i > nb_deps_not_carried_by_j
-	    || access_strides_i < access_strides_j)
+	    || double_int_ucmp (access_strides_i, access_strides_j) < 0)
 	  {
 	    lambda_matrix_row_exchange (LTM_MATRIX (trans),
 					loop_i->depth - first_loop->depth,