1 files changed, 33 insertions, 0 deletions
diff --git a/llvm/test/Transforms/IPConstantProp/user-with-multiple-uses.ll b/llvm/test/Transforms/IPConstantProp/user-with-multiple-uses.ll
new file mode 100644
index 00000000000..3146709aec6
--- /dev/null
+++ b/llvm/test/Transforms/IPConstantProp/user-with-multiple-uses.ll
@@ -0,0 +1,33 @@
+; RUN: opt < %s -S -ipsccp | FileCheck %s
+; PR5596
+
+; IPSCCP should propagate the 0 argument, eliminate the switch, and propagate
+; the result.
+
+; CHECK: define i32 @main() #0 {
+; CHECK-NEXT: entry:
+; CHECK-NEXT: %call2 = tail call i32 @wwrite(i64 0) [[NUW:#[0-9]+]]
+; CHECK-NEXT: ret i32 123
+
+define i32 @main() noreturn nounwind {
+entry:
+  %call2 = tail call i32 @wwrite(i64 0) nounwind
+  ret i32 %call2
+}
+
+define internal i32 @wwrite(i64 %i) nounwind {
+entry:
+  switch i64 %i, label %sw.default [
+    i64 3, label %return
+    i64 10, label %return
+  ]
+
+sw.default:
+  ret i32 123
+
+return:
+  ret i32 0
+}
+
+; CHECK: attributes #0 = { noreturn nounwind }
+; CHECK: attributes #1 = { nounwind }