Relanding r357928 with fixed debuginfo check.

[MS] Add metadata for __declspec(allocator)

Original summary:
Emit !heapallocsite in the metadata for calls to functions marked with
__declspec(allocator). Eventually this will be emitted as S_HEAPALLOCSITE debug
info in codeview.

Differential Revision: https://reviews.llvm.org/D60237

llvm-svn: 358307
diff --git a/clang/lib/CodeGen/CGDebugInfo.h b/clang/lib/CodeGen/CGDebugInfo.h
index 67331b6..fd7df08 100644
--- a/clang/lib/CodeGen/CGDebugInfo.h
+++ b/clang/lib/CodeGen/CGDebugInfo.h
@@ -476,6 +476,10 @@
   /// Emit standalone debug info for a type.
   llvm::DIType *getOrCreateStandaloneType(QualType Ty, SourceLocation Loc);
 
+  /// Add heapallocsite metadata for MSAllocator calls.
+  void addHeapAllocSiteMetadata(llvm::Instruction *CallSite, QualType Ty,
+                                SourceLocation Loc);
+
   void completeType(const EnumDecl *ED);
   void completeType(const RecordDecl *RD);
   void completeRequiredType(const RecordDecl *RD);