re PR tree-optimization/53550 (ICE with -O{1,2,3} -fprefetch-loop-arrays in…

re PR tree-optimization/53550 (ICE with -O{1,2,3} -fprefetch-loop-arrays in build2_stat, at tree.c:3803)

	PR tree-optimization/53550
	* tree-ssa-loop-niter.c (number_of_iterations_cond): If type
	is POINTER_TYPE_P, use sizetype as step type instead of type.

	* gcc.dg/pr53550.c: New test.

From-SVN: r188169

gcc/ChangeLog

+2012-06-04  Jakub Jelinek  <jakub@redhat.com>
+
+	PR tree-optimization/53550
+	* tree-ssa-loop-niter.c (number_of_iterations_cond): If type
+	is POINTER_TYPE_P, use sizetype as step type instead of type.
+
 2012-06-04  Richard Guenther  <rguenther@suse.de>
 
 	* tree-data-ref.c (have_similar_memory_accesses_1): Remove.

gcc/testsuite/ChangeLog

+2012-06-04  Jakub Jelinek  <jakub@redhat.com>
+
+	PR tree-optimization/53550
+	* gcc.dg/pr53550.c: New test.
+
 2012-06-04  Richard Guenther  <rguenther@suse.de>
 
 	* gcc.dg/tree-ssa/ldist-11.c: Enable -ftree-loop-distribute-patterns.

gcc/testsuite/gcc.dg/pr53550.c

+/* PR tree-optimization/53550 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -fprefetch-loop-arrays -w" } */
+
+int *
+foo (int *x)
+{
+  int *a = x + 10, *b = x, *c = a;
+  while (b != c)
+    *--c = *b++;
+  return x;
+}

gcc/tree-ssa-loop-niter.c

@@ -1275,13 +1275,14 @@ number_of_iterations_cond (struct loop *loop,
      practice, but it is simple enough to manage.  */
   if (!integer_zerop (iv0->step) && !integer_zerop (iv1->step))
     {
+      tree step_type = POINTER_TYPE_P (type) ? sizetype : type;
       if (code != NE_EXPR)
 	return false;
 
-      iv0->step = fold_binary_to_constant (MINUS_EXPR, type,
+      iv0->step = fold_binary_to_constant (MINUS_EXPR, step_type,
 					   iv0->step, iv1->step);
       iv0->no_overflow = false;
-      iv1->step = build_int_cst (type, 0);
+      iv1->step = build_int_cst (step_type, 0);
       iv1->no_overflow = true;
     }