[CodeGen] Align rtti and vtable data

Previously the alignment on the newly created rtti/typeinfo data was largely
not set, meaning that DataLayout::getPreferredAlignment was free to overalign
it to 16 bytes. This causes unnecessary code bloat.

Differential Revision: https://reviews.llvm.org/D51416

llvm-svn: 342053
diff --git a/clang/lib/CodeGen/CodeGenModule.h b/clang/lib/CodeGen/CodeGenModule.h
index 91f3d94..ae7f7f3 100644
--- a/clang/lib/CodeGen/CodeGenModule.h
+++ b/clang/lib/CodeGen/CodeGenModule.h
@@ -764,7 +764,8 @@
   /// bitcast to the new variable.
   llvm::GlobalVariable *
   CreateOrReplaceCXXRuntimeVariable(StringRef Name, llvm::Type *Ty,
-                                    llvm::GlobalValue::LinkageTypes Linkage);
+                                    llvm::GlobalValue::LinkageTypes Linkage,
+                                    unsigned Alignment);
 
   llvm::Function *
   CreateGlobalInitOrDestructFunction(llvm::FunctionType *ty, const Twine &name,