gcc/

	PR tree-optimization/22026
	* tree-vrp.c (extract_range_from_binary_expr): Drop to
	VR_VARYING if a binary expression involving VR_ANTI_RANGE is
	PLUS_EXPR, MINUS_EXPR, or unsigned MULT_EXPR.

testsuite/
	PR tree-optimization/22026
	* gcc.dg/tree-ssa/pr22026.c: New.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@101328 138bc75d-0d04-0410-961f-82ee72b054a4

2 files changed, 54 insertions, 0 deletions

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 419e012bd44..71961848bd3 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2005-06-26  Kazu Hirata  <kazu@codesourcery.com>
+
+	PR tree-optimization/22026
+	* gcc.dg/tree-ssa/pr22026.c: New.
+
 2005-06-25  Thomas Koenig <Thomas.Koenig@online.de>
 
 	PR libfortran/21144
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr22026.c b/gcc/testsuite/gcc.dg/tree-ssa/pr22026.c
new file mode 100644
index 00000000000..e56e4a124ad
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/pr22026.c
@@ -0,0 +1,49 @@
+/* PR tree-optimization/22026
+   VRP used think that ~[0,0] + ~[0,0] = ~[0,0], which is wrong.  The
+   same applies to subtraction and unsigned multiplication.  */
+
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-vrp" } */
+
+int
+plus (int x, int y)
+{
+  if (x != 0)
+    if (y != 0)
+      {
+        int z = x + y;
+        if (z != 0)
+          return 1;
+      }
+  return 0;
+}
+
+int
+minus (int x, int y)
+{
+  if (x != 0)
+    if (y != 0)
+      {
+        int z = x - y;
+        if (z != 0)
+          return 1;
+      }
+  return 0;
+}
+
+int
+mult (unsigned x, unsigned y)
+{
+  if (x != 0)
+    if (y != 0)
+      {
+	unsigned z = x * y;
+	if (z != 0)
+	  return 1;
+      }
+  return 0;
+}
+
+/* None of the predicates can be folded in these functions.  */
+/* { dg-final { scan-tree-dump-times "Folding predicate" 0 "vrp" } } */
+/* { dg-final { cleanup-tree-dump "vrp" } } */