re PR bootstrap/57266 (comparison between signed and unsigned integer expressions...

2013-05-14  Marc Glisse  <marc.glisse@inria.fr>

	PR bootstrap/57266
	* fold-const.c (fold_binary_loc) <shift>: Use an unsigned
	variable for the shift amount. Check that we shift by non-negative
	amounts.

From-SVN: r198880

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 15cafbb..76ab15d 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,10 @@
+2013-05-14  Marc Glisse  <marc.glisse@inria.fr>
+
+       PR bootstrap/57266
+       * fold-const.c (fold_binary_loc) <shift>: Use an unsigned
+       variable for the shift amount. Check that we shift by non-negative
+       amounts.
+
 2013-05-14  Chung-Lin Tang  <cltang@codesourcery.com>
 
        PR target/42017

diff --git a/gcc/fold-const.c b/gcc/fold-const.c
index cbd3445..5d6bbbb 100644 (file)
--- a/gcc/fold-const.c
+++ b/gcc/fold-const.c
@@ -12423,13 +12423,13 @@ fold_binary_loc (location_t loc,
       prec = element_precision (type);
 
       /* Turn (a OP c1) OP c2 into a OP (c1+c2).  */
-      if (TREE_CODE (op0) == code && host_integerp (arg1, false)
+      if (TREE_CODE (op0) == code && host_integerp (arg1, true)
          && TREE_INT_CST_LOW (arg1) < prec
-         && host_integerp (TREE_OPERAND (arg0, 1), false)
+         && host_integerp (TREE_OPERAND (arg0, 1), true)
          && TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1)) < prec)
        {
-         HOST_WIDE_INT low = (TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1))
-                              + TREE_INT_CST_LOW (arg1));
+         unsigned int low = (TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1))
+                             + TREE_INT_CST_LOW (arg1));
 
          /* Deal with a OP (c1 + c2) being undefined but (a OP c1) OP c2
             being well defined.  */