Factor code into CXXRecordDecl::getTemplateInstantiationPattern() helper

This moves some code from SemaType.cpp's hasVisibleDefinition() into
DeclCXX.cpp so that it can be used elsewhere. I found one other instance
of code trying to do the same thing, there are probably more. Search for
getInstantiatedFrom() to try to find more.

No functionality change.

Reviewed By: rsmith

Subscribers: cfe-commits

Differential Revision: http://reviews.llvm.org/D5783

llvm-svn: 219714

1 files changed, 2 insertions, 15 deletions

diff --git a/clang/lib/Sema/SemaLookup.cpp b/clang/lib/Sema/SemaLookup.cpp
index 639e6511217..cbeebb2ac98 100644
--- a/clang/lib/Sema/SemaLookup.cpp
+++ b/clang/lib/Sema/SemaLookup.cpp
@@ -1175,21 +1175,8 @@ static Module *getDefiningModule(Decl *Entity) {
     if (FunctionDecl *Pattern = FD->getTemplateInstantiationPattern())
       Entity = Pattern;
   } else if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Entity)) {
-    // If it's a class template specialization, find the template or partial
-    // specialization from which it was instantiated.
-    if (ClassTemplateSpecializationDecl *SpecRD =
-            dyn_cast<ClassTemplateSpecializationDecl>(RD)) {
-      llvm::PointerUnion<ClassTemplateDecl*,
-                         ClassTemplatePartialSpecializationDecl*> From =
-          SpecRD->getInstantiatedFrom();
-      if (ClassTemplateDecl *FromTemplate = From.dyn_cast<ClassTemplateDecl*>())
-        Entity = FromTemplate->getTemplatedDecl();
-      else if (From)
-        Entity = From.get<ClassTemplatePartialSpecializationDecl*>();
-      // Otherwise, it's an explicit specialization.
-    } else if (MemberSpecializationInfo *MSInfo =
-                   RD->getMemberSpecializationInfo())
-      Entity = getInstantiatedFrom(RD, MSInfo);
+    if (CXXRecordDecl *Pattern = RD->getTemplateInstantiationPattern())
+      Entity = Pattern;
   } else if (EnumDecl *ED = dyn_cast<EnumDecl>(Entity)) {
     if (MemberSpecializationInfo *MSInfo = ED->getMemberSpecializationInfo())
       Entity = getInstantiatedFrom(ED, MSInfo);