[Review, -cxx-abi microsoft] Implement proper handling of virtual destructors (single-inheritance case)

[John McCall]

On Feb 12, 2013, at 5:28 AM, Timur Iskhodzhanov <timurrrr at google.com> wrote:
> I've renamed the -constructors test to -structors in r174966,
> updating the patch accoridngly.

+void MicrosoftCXXNameMangler::mangleCXXDtorType(CXXDtorType T) {
+  switch (T) {
+  case Dtor_Deleting:
+    Out << "?_G";
+    break;
+  case Dtor_Base:
+    // FIXME: We should be asked to mangle base dtors.
+    // However, fixing this would require larger changes to the CodeGenModule.
+    // Please put llvm_unreachable here when CGM is changed.
+    // For now, just mangle a base dtor the same way as a complete dtor...
+  case Dtor_Complete:
+    Out << "?1";
+    break;
+  default:
+    llvm_unreachable("Unsupported dtor type?");
+  }

Please have the concrete cases return, remove the default case, and
put the unreachable after the switch.

-  ImplicitParamDecl *&getVTTDecl(CodeGenFunction &CGF) {
-    return CGF.CXXVTTDecl;
+  ImplicitParamDecl *&getStructorImplicitParamDecl(CodeGenFunction &CGF) {
+    return CGF.CXXStructorImplicitParamDecl;
   }
-  llvm::Value *&getVTTValue(CodeGenFunction &CGF) {
-    return CGF.CXXVTTValue;
+  llvm::Value *&getStructorImplicitParamValue(CodeGenFunction &CGF) {
+    return CGF.CXXStructorImplicitParamValue;
   }

Adding the new functions makes sense, but for now, please leave the old
functions in-place.  Every place that calls getVTT{Decl,Value} is something
that needs to be abstracted properly.

Otherwise, looks fine.

John.