re PR middle-end/34070 (Wrong code for (int)x%4)

2007-11-12  Richard Guenther  <rguenther@suse.de>

	PR middle-end/34070
	* fold-const.c (fold_binary): If testing for non-negative
	operands with tree_expr_nonnegative_warnv_p make sure to
	use op0 which has all (sign) conversions retained.

	* gcc.c-torture/execute/pr34070-1.c: New testcase.
	* gcc.c-torture/execute/pr34070-2.c: Likewise.

From-SVN: r130098

gcc/ChangeLog

 2007-11-12  Richard Guenther  <rguenther@suse.de>
 
+	PR middle-end/34070
+	* fold-const.c (fold_binary): If testing for non-negative
+	operands with tree_expr_nonnegative_warnv_p make sure to
+	use op0 which has all (sign) conversions retained.
+
+2007-11-12  Richard Guenther  <rguenther@suse.de>
+
 	PR middle-end/34027
 	* fold-const.c (fold_binary): Fold n - (n / m) * m to n % m.
 	(fold_binary): Fold unsinged FLOOR_DIV_EXPR to TRUNC_DIV_EXPR.

gcc/fold-const.c

@@ -11230,7 +11230,7 @@ fold_binary (enum tree_code code, tree type, tree op0, tree op1)
       strict_overflow_p = false;
       if (TREE_CODE (arg1) == LSHIFT_EXPR
 	  && (TYPE_UNSIGNED (type)
-	      || tree_expr_nonnegative_warnv_p (arg0, &strict_overflow_p)))
+	      || tree_expr_nonnegative_warnv_p (op0, &strict_overflow_p)))
 	{
 	  tree sval = TREE_OPERAND (arg1, 0);
 	  if (integer_pow2p (sval) && tree_int_cst_sgn (sval) > 0)
@@ -11356,7 +11356,7 @@ fold_binary (enum tree_code code, tree type, tree op0, tree op1)
       strict_overflow_p = false;
       if ((code == TRUNC_MOD_EXPR || code == FLOOR_MOD_EXPR)
 	  && (TYPE_UNSIGNED (type)
-	      || tree_expr_nonnegative_warnv_p (arg0, &strict_overflow_p)))
+	      || tree_expr_nonnegative_warnv_p (op0, &strict_overflow_p)))
 	{
 	  tree c = arg1;
 	  /* Also optimize A % (C << N)  where C is a power of 2,

gcc/testsuite/ChangeLog

 2007-11-12  Richard Guenther  <rguenther@suse.de>
 
+	PR middle-end/34070
+	* gcc.c-torture/execute/pr34070-1.c: New testcase.
+	* gcc.c-torture/execute/pr34070-2.c: Likewise.
+
+2007-11-12  Richard Guenther  <rguenther@suse.de>
+
 	PR middle-end/34027
 	* gcc.dg/pr34027-1.c: New testcase.
 	* gcc.dg/pr34027-2.c: Likewise.

gcc/testsuite/gcc.c-torture/execute/pr34070-1.c

+extern void abort (void);
+
+int f(unsigned int x)
+{
+    return ((int)x) % 4;
+}
+
+int main()
+{
+  if (f(-1) != -1)
+    abort ();
+  return 0;
+}

gcc/testsuite/gcc.c-torture/execute/pr34070-2.c

+extern void abort (void);
+
+int f(unsigned int x, int n)
+{
+    return ((int)x) / (1 << n);
+}
+
+int main()
+{
+  if (f(-1, 1) != 0)
+    abort ();
+  return 0;
+}