diff --git a/llvm/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp b/llvm/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp
index 5c56e474b3d6..ee5e1a115482 100644
--- a/llvm/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp
@@ -249,8 +249,10 @@ SDValue DAGTypeLegalizer::PromoteIntRes_BITCAST(SDNode *N) {
     return DAG.getNode(ISD::BITCAST, dl, NOutVT, InOp);
   }
   case TargetLowering::TypeWidenVector:
-    if (NOutVT.bitsEq(NInVT))
-      // The input is widened to the same size.  Convert to the widened value.
+    // The input is widened to the same size. Convert to the widened value.
+    // Make sure that the outgoing value is not a vector, because this would
+    // make us bitcast between two vectors which are legalized in different ways.
+    if (NOutVT.bitsEq(NInVT) && !NOutVT.isVector())
       return DAG.getNode(ISD::BITCAST, dl, NOutVT, GetWidenedVector(InOp));
   }
 
diff --git a/llvm/test/CodeGen/X86/2012-01-18-vbitcast.ll b/llvm/test/CodeGen/X86/2012-01-18-vbitcast.ll
new file mode 100644
index 000000000000..8a3ccc8dfda5
--- /dev/null
+++ b/llvm/test/CodeGen/X86/2012-01-18-vbitcast.ll
@@ -0,0 +1,14 @@
+; RUN: llc < %s -march=x86-64 -mcpu=corei7 -mtriple=x86_64-pc-win32 | FileCheck %s
+
+;CHECK: vcast
+define <2 x i32> @vcast(<2 x float> %a, <2 x float> %b) {
+;CHECK: pshufd
+;CHECK: pshufd
+  %af = bitcast <2 x float> %a to <2 x i32>
+  %bf = bitcast <2 x float> %b to <2 x i32>
+  %x = sub <2 x i32> %af, %bf
+;CHECK: psubq
+  ret <2 x i32> %x
+;CHECK: ret
+}
+