MS ABI: Implement copy-ctor closures, finish implementing throw

This adds support for copy-constructor closures.  These are generated
when the C++ runtime has to call a copy-constructor with a particular
calling convention or with default arguments substituted in to the call.

Because the runtime has no mechanism to call the function with a
different calling convention or know-how to evaluate the default
arguments at run-time, we create a thunk which will do all the
appropriate work and package it in a way the runtime can use.

Differential Revision: http://reviews.llvm.org/D8225

llvm-svn: 231952

1 files changed, 12 insertions, 0 deletions

diff --git a/clang/lib/AST/MicrosoftCXXABI.cpp b/clang/lib/AST/MicrosoftCXXABI.cpp
index 71b21bff77c..fb3beff4beb 100644
--- a/clang/lib/AST/MicrosoftCXXABI.cpp
+++ b/clang/lib/AST/MicrosoftCXXABI.cpp
@@ -64,6 +64,8 @@ public:
 class MicrosoftCXXABI : public CXXABI {
   ASTContext &Context;
   llvm::SmallDenseMap<CXXRecordDecl *, CXXConstructorDecl *> RecordToCopyCtor;
+  llvm::SmallDenseMap<std::pair<const CXXConstructorDecl *, unsigned>, Expr *>
+      CtorToDefaultArgExpr;
 
 public:
   MicrosoftCXXABI(ASTContext &Ctx) : Context(Ctx) { }
@@ -92,6 +94,16 @@ public:
       Layout.getNonVirtualSize() == PointerSize * 2;
   }
 
+  void addDefaultArgExprForConstructor(const CXXConstructorDecl *CD,
+                                       unsigned ParmIdx, Expr *DAE) override {
+    CtorToDefaultArgExpr[std::make_pair(CD, ParmIdx)] = DAE;
+  }
+
+  Expr *getDefaultArgExprForConstructor(const CXXConstructorDecl *CD,
+                                        unsigned ParmIdx) override {
+    return CtorToDefaultArgExpr[std::make_pair(CD, ParmIdx)];
+  }
+
   const CXXConstructorDecl *
   getCopyConstructorForExceptionObject(CXXRecordDecl *RD) override {
     return RecordToCopyCtor[RD];