[VectorUtils] Use namespace for InterleaveGroup template specialization.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346759 91177308-0d34-0410-b5e6-96231b3b80d8

Author: fhahn

lib/Analysis/VectorUtils.cpp

@@ -966,15 +966,17 @@ void InterleavedAccessInfo::invalidateGroupsRequiringScalarEpilogue() {
   RequiresScalarEpilogue = false;
 }
 
+template <typename InstT>
+void InterleaveGroup<InstT>::addMetadata(InstT *NewInst) const {
+  llvm_unreachable("addMetadata can only be used for Instruction");
+}
+
+namespace llvm {
 template <>
 void InterleaveGroup<Instruction>::addMetadata(Instruction *NewInst) const {
   SmallVector<Value *, 4> VL;
   std::transform(Members.begin(), Members.end(), std::back_inserter(VL),
                  [](std::pair<int, Instruction *> p) { return p.second; });
   propagateMetadata(NewInst, VL);
 }
-
-template <typename InstT>
-void InterleaveGroup<InstT>::addMetadata(InstT *NewInst) const {
-  llvm_unreachable("addMetadata can only be used for Instruction");
 }