* simplify-rtx.c (simplify_relational_operation): Two signed

values with equal high words are less/greater than each other if
their low words are less/greater when considered as unsigned.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@35080 138bc75d-0d04-0410-961f-82ee72b054a4

gcc/ChangeLog

+2000-07-17  Geoffrey Keating  <geoffk@cygnus.com>
+
+	* simplify-rtx.c (simplify_relational_operation): Two signed
+	values with equal high words are less/greater than each other if
+	their low words are less/greater when considered as unsigned.
+
 Mon Jul 17 02:37:06 2000  Marc Espie <espie@openbsd.org>
 	* configure.in (vax-*-openbsd):  Change to new style configuration,

gcc/simplify-rtx.c

@@ -1792,8 +1792,8 @@ simplify_relational_operation (code, mode, op0, op1)
 	}
 
       equal = (h0u == h1u && l0u == l1u);
-      op0lt = (h0s < h1s || (h0s == h1s && l0s < l1s));
-      op1lt = (h1s < h0s || (h1s == h0s && l1s < l0s));
+      op0lt = (h0s < h1s || (h0s == h1s && l0u < l1u));
+      op1lt = (h1s < h0s || (h1s == h0s && l1u < l0u));
       op0ltu = (h0u < h1u || (h0u == h1u && l0u < l1u));
       op1ltu = (h1u < h0u || (h1u == h0u && l1u < l0u));
     }

gcc/testsuite/ChangeLog

+2000-07-17  Geoffrey Keating  <geoffk@cygnus.com>
+
+	* gcc.c-torture/execute/20000717-2.c: New test.
+
 2000-07-17  Joseph S. Myers  <jsm28@cam.ac.uk>
 
 	* gcc.dg/c90-digraph-1.c, gcc.dg/c94-digraph.c,

gcc/testsuite/gcc.c-torture/execute/20000717-2.c

+static void
+compare (long long foo)
+{
+  if (foo < 4294967297LL)
+    abort();
+}
+int main(void)
+{
+  compare (8589934591LL);
+  exit (0);
+}