Handle a special case xor undef, undef -> 0. Technically this should be transformed to undef. But this is such a common idiom (misuse) we are going to handle it.

llvm-svn: 48792

1 files changed, 11 insertions, 0 deletions

diff --git a/llvm/test/CodeGen/X86/xor-undef.ll b/llvm/test/CodeGen/X86/xor-undef.ll
new file mode 100644
index 00000000000..0e60d4ef087
--- /dev/null
+++ b/llvm/test/CodeGen/X86/xor-undef.ll
@@ -0,0 +1,11 @@
+; RUN: llvm-as < %s | llc -march=x86 -mattr=+sse2 | grep xor | count 2
+
+define <4 x i32> @t1() {
+	%tmp = xor <4 x i32> undef, undef
+	ret <4 x i32> %tmp
+}
+
+define i32 @t2() {
+	%tmp = xor i32 undef, undef
+	ret i32 %tmp
+}