diff --git a/test/CodeGen/X86/pr20088.ll b/test/CodeGen/X86/pr20088.ll
index d7aab7fcba4..3a829622424 100644
--- a/test/CodeGen/X86/pr20088.ll
+++ b/test/CodeGen/X86/pr20088.ll
@@ -1,4 +1,4 @@
-; RUN: llc < %s -mattr=+avx | FileCheck %s
+; RUN: llc < %s -march=x86-64 -mattr=+avx | FileCheck %s
 
 declare <16 x i8> @llvm.x86.sse41.pblendvb(<16 x i8>, <16 x i8>, <16 x i8>)