1 files changed, 71 insertions, 0 deletions
diff --git a/clang/lib/AST/MicrosoftCXXABI.cpp b/clang/lib/AST/MicrosoftCXXABI.cpp
new file mode 100644
index 0000000..f33d6fe
--- /dev/null
+++ b/clang/lib/AST/MicrosoftCXXABI.cpp
@@ -0,0 +1,71 @@
+//===------- MicrosoftCXXABI.cpp - AST support for the Microsoft C++ ABI --===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This provides C++ AST support targeting the Microsoft Visual C++
+// ABI.
+//
+//===----------------------------------------------------------------------===//
+
+#include "CXXABI.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/AST/DeclCXX.h"
+#include "clang/AST/RecordLayout.h"
+#include "clang/AST/Type.h"
+#include "clang/Basic/TargetInfo.h"
+
+using namespace clang;
+
+namespace {
+class MicrosoftCXXABI : public CXXABI {
+  ASTContext &Context;
+public:
+  MicrosoftCXXABI(ASTContext &Ctx) : Context(Ctx) { }
+
+  unsigned getMemberPointerSize(const MemberPointerType *MPT) const;
+
+  CallingConv getDefaultMethodCallConv() const {
+    if (Context.getTargetInfo().getTriple().getArch() == llvm::Triple::x86)
+      return CC_X86ThisCall;
+    else
+      return CC_C;
+  }
+
+  bool isNearlyEmpty(const CXXRecordDecl *RD) const {
+    // FIXME: Audit the corners
+    if (!RD->isDynamicClass())
+      return false;
+
+    const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
+    
+    // In the Microsoft ABI, classes can have one or two vtable pointers.
+    CharUnits PointerSize = 
+      Context.toCharUnitsFromBits(Context.getTargetInfo().getPointerWidth(0));
+    return Layout.getNonVirtualSize() == PointerSize ||
+      Layout.getNonVirtualSize() == PointerSize * 2;
+  }    
+};
+}
+
+unsigned MicrosoftCXXABI::getMemberPointerSize(const MemberPointerType *MPT) const {
+  QualType Pointee = MPT->getPointeeType();
+  CXXRecordDecl *RD = MPT->getClass()->getAsCXXRecordDecl();
+  if (RD->getNumVBases() > 0) {
+    if (Pointee->isFunctionType())
+      return 3;
+    else
+      return 2;
+  } else if (RD->getNumBases() > 1 && Pointee->isFunctionType())
+    return 2;
+  return 1;
+}
+
+CXXABI *clang::CreateMicrosoftCXXABI(ASTContext &Ctx) {
+  return new MicrosoftCXXABI(Ctx);
+}
+