[PATCH] Testcase for VRP range-anti-range merging

[Richard Guenther]

Tested on x86_64-unknown-linux-gnu, applied.

Richard.

2012-06-14  Richard Guenther  <rguent...@suse.de>

        * gcc.dg/tree-ssa/vrp.h: New testcase.
        * gcc.dg/tree-ssa/vrp68.c: Likewise.

Index: gcc/testsuite/gcc.dg/tree-ssa/vrp.h
===================================================================
--- gcc/testsuite/gcc.dg/tree-ssa/vrp.h (revision 0)
+++ gcc/testsuite/gcc.dg/tree-ssa/vrp.h (revision 0)
@@ -0,0 +1,27 @@
+extern void link_error(void);
+
+#define RANGE(name, min, max) \
+  if (name < min || name > max) \
+    return;
+#define ANTI_RANGE(name, min, max) \
+  if (name >= min && name <= max) \
+    return;
+#define MERGE(cond, name1, name2) \
+  if (cond) \
+    name1 = name2;
+#define CHECK_RANGE(expr, min, max) \
+  do { \
+     __typeof__ (expr) v = (expr); \
+     if (v < min) link_error(); \
+     if (v > max) link_error(); \
+     if (v < min || v > max) link_error (); \
+  } while (0) 
+#define CHECK_ANTI_RANGE(expr, min, max) \
+  do { \
+    __typeof__ (expr) v = (expr); \
+    if (v >= min) \
+      if (v <= max) \
+        link_error(); \
+    if (v >= min && v <= max) \
+      link_error(); \
+  } while (0)
Index: gcc/testsuite/gcc.dg/tree-ssa/vrp68.c
===================================================================
--- gcc/testsuite/gcc.dg/tree-ssa/vrp68.c       (revision 0)
+++ gcc/testsuite/gcc.dg/tree-ssa/vrp68.c       (revision 0)
@@ -0,0 +1,24 @@
+/* { dg-do link } */
+/* { dg-options "-O2 -fdump-tree-vrp1" } */
+
+#include "vrp.h"
+
+void test1 (int i, int j, int b)
+{
+  RANGE(i, 2, 6);
+  ANTI_RANGE(j, 1, 7);
+  MERGE(b, i, j);
+  CHECK_ANTI_RANGE(i, 7, 7);
+  CHECK_ANTI_RANGE(i, 1, 1);
+  /* If we swap the anti-range tests the ~[6, 6] test is never eliminated.  */
+}
+int main() { }
+
+/* While subsequent VRP/DOM passes manage to even recognize the ~[6, 6]
+   test as redundant a single VRP run will arbitrarily choose ~[0, 0] when
+   merging [1, 5] with ~[0, 6] so the first VRP pass can only eliminate
+   the ~[0, 0] check as redundant.  */
+
+/* { dg-final { scan-tree-dump-times "vrp1" 0 "link_error" { xfail *-*-* } } } 
*/
+/* { dg-final { scan-tree-dump-times "vrp1" 1 "link_error" } } */
+/* { dg-final { cleanup-tree-dump "vrp1" } } */