re PR tree-optimization/47155 (ccp caused miscompilation)

	PR tree-optimization/47155
	* tree-ssa-ccp.c (bit_value_binop_1): Use r1type instead of type
	when computing uns.

	* gcc.c-torture/execute/pr47155.c: New test.

From-SVN: r168440

gcc/ChangeLog

 2011-01-03  Jakub Jelinek  <jakub@redhat.com>
 
+	PR tree-optimization/47155
+	* tree-ssa-ccp.c (bit_value_binop_1): Use r1type instead of type
+	when computing uns.
+
 	PR rtl-optimization/47157
 	* combine.c (try_combine): If undobuf.other_insn becomes
 	(set (pc) (pc)) jump, call update_cfg_for_uncondjump on it

gcc/testsuite/ChangeLog

 2011-01-03  Jakub Jelinek  <jakub@redhat.com>
 
+	PR tree-optimization/47155
+	* gcc.c-torture/execute/pr47155.c: New test.
+
 	PR rtl-optimization/47157
 	* gcc.c-torture/compile/pr47157.c: New test.
 

gcc/testsuite/gcc.c-torture/execute/pr47155.c

+/* PR tree-optimization/47155 */
+
+unsigned int a;
+static signed char b = -127;
+int c = 1;
+
+int
+main (void)
+{
+  a = b <= (unsigned char) (-6 * c);
+  if (!a)
+    __builtin_abort ();
+  return 0;
+}

gcc/tree-ssa-ccp.c

@@ -1764,8 +1764,8 @@ bit_value_binop_1 (enum tree_code code, tree type,
 		   tree r1type, double_int r1val, double_int r1mask,
 		   tree r2type, double_int r2val, double_int r2mask)
 {
-  bool uns = (TREE_CODE (type) == INTEGER_TYPE
-	      && TYPE_IS_SIZETYPE (type) ? 0 : TYPE_UNSIGNED (type));
+  bool uns = (TREE_CODE (r1type) == INTEGER_TYPE
+	      && TYPE_IS_SIZETYPE (r1type) ? 0 : TYPE_UNSIGNED (r1type));
   /* Assume we'll get a constant result.  Use an initial varying value,
      we fall back to varying in the end if necessary.  */
   *mask = double_int_minus_one;