| //===------- 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(bool isVariadic) const { |
| if (!isVariadic && 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->getTypeForDecl()->isIncompleteType()) { |
| if (RD->hasAttr<SingleInheritanceAttr>()) |
| return 1; |
| else if (RD->hasAttr<MultipleInheritanceAttr>()) |
| return 2; |
| else |
| return 3; |
| } |
| |
| 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); |
| } |
| |