test that reassociate can handle shifts

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@21760 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/test/Transforms/Reassociate/shifttest.ll b/test/Transforms/Reassociate/shifttest.ll
new file mode 100644 (file)
index 0000000..6ca6622
--- /dev/null
+++ b/test/Transforms/Reassociate/shifttest.ll
@@ -0,0 +1,10 @@
+; With shl->mul reassociation, we can see that this is (shl A, 9) * A
+;
+; RUN: llvm-as < %s | opt -reassociate -instcombine | llvm-dis | grep 'shl .*, ubyte 9'
+
+int %test(int %A, int %B) {
+       %X = shl int %A, ubyte 5
+       %Y = shl int %A, ubyte 4
+       %Z = mul int %Y, %X
+       ret int %Z
+}