Make thunk this/return adjustment ABI-specific. Also, fix the return adjustment when using -cxx-abi microsoft

Reviewed at http://llvm-reviews.chandlerc.com/D2026

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@193679 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGCXXABI.h b/lib/CodeGen/CGCXXABI.h
index c76769f..44bdf66 100644
--- a/lib/CodeGen/CGCXXABI.h
+++ b/lib/CodeGen/CGCXXABI.h
@@ -356,6 +356,14 @@
 
   virtual void setThunkLinkage(llvm::Function *Thunk, bool ForVTable) = 0;
 
+  virtual llvm::Value *performThisAdjustment(CodeGenFunction &CGF,
+                                             llvm::Value *This,
+                                             const ThisAdjustment &TA) = 0;
+
+  virtual llvm::Value *performReturnAdjustment(CodeGenFunction &CGF,
+                                               llvm::Value *Ret,
+                                               const ReturnAdjustment &RA) = 0;
+
   virtual void EmitReturnFromThunk(CodeGenFunction &CGF,
                                    RValue RV, QualType ResultType);