1 files changed, 21 insertions, 0 deletions
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr21001.c b/gcc/testsuite/gcc.dg/tree-ssa/pr21001.c
new file mode 100644
index 000000000..84280b39c
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/pr21001.c
@@ -0,0 +1,21 @@
+/* PR tree-optimization/21001
+   VRP did not insert ASSERT_EXPRs when the variable tested in a
+   COND_EXPR is a single-use variable.  By propagating the definition
+   of the single-use variable into the COND_EXPR, we can get useful
+   range infomation out of the conditional.  */
+
+/* { dg-do compile } */
+/* { dg-options "-O2 -fno-tree-dominator-opts -fdump-tree-vrp1-details" } */
+
+int
+foo (int a)
+{
+  int b = a != 0;
+  if (b)
+    if (a != 0)
+      return 1;
+  return 0;
+}
+
+/* { dg-final { scan-tree-dump-times "Folding predicate" 1 "vrp1"} } */
+/* { dg-final { cleanup-tree-dump "vrp1" } } */