1 files changed, 15 insertions, 0 deletions
diff --git a/test/Transforms/InstCombine/2004-02-23-ShiftShiftOverflow.ll b/test/Transforms/InstCombine/2004-02-23-ShiftShiftOverflow.ll
new file mode 100644
index 000000000000..3a4b66157dfe
--- /dev/null
+++ b/test/Transforms/InstCombine/2004-02-23-ShiftShiftOverflow.ll
@@ -0,0 +1,15 @@
+; RUN: llvm-as < %s | opt -instcombine | llvm-dis | not grep 34
+
+define i32 @test(i32 %X) {
+        ; Do not fold into shr X, 34, as this uses undefined behavior!
+        %Y = ashr i32 %X, 17            ; <i32> [#uses=1]
+        %Z = ashr i32 %Y, 17            ; <i32> [#uses=1]
+        ret i32 %Z
+}
+
+define i32 @test2(i32 %X) {
+        ; Do not fold into shl X, 34, as this uses undefined behavior!
+        %Y = shl i32 %X, 17             ; <i32> [#uses=1]
+        %Z = shl i32 %Y, 17             ; <i32> [#uses=1]
+        ret i32 %Z
+}