| //===------- ItaniumCXXABI.cpp - AST support for the Itanium 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 Itanium C++ ABI, which is |
| // documented at: |
| // http://www.codesourcery.com/public/cxx-abi/abi.html |
| // http://www.codesourcery.com/public/cxx-abi/abi-eh.html |
| // |
| // It also supports the closely-related ARM C++ ABI, documented at: |
| // http://infocenter.arm.com/help/topic/com.arm.doc.ihi0041c/IHI0041C_cppabi.pdf |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "CXXABI.h" |
| #include "clang/AST/ASTContext.h" |
| #include "clang/AST/DeclCXX.h" |
| #include "clang/AST/MangleNumberingContext.h" |
| #include "clang/AST/RecordLayout.h" |
| #include "clang/AST/Type.h" |
| #include "clang/Basic/TargetInfo.h" |
| |
| using namespace clang; |
| |
| namespace { |
| |
| /// \brief Keeps track of the mangled names of lambda expressions and block |
| /// literals within a particular context. |
| class ItaniumNumberingContext : public MangleNumberingContext { |
| llvm::DenseMap<IdentifierInfo*, unsigned> VarManglingNumbers; |
| |
| public: |
| /// Variable decls are numbered by identifier. |
| virtual unsigned getManglingNumber(const VarDecl *VD) { |
| return ++VarManglingNumbers[VD->getIdentifier()]; |
| } |
| }; |
| |
| class ItaniumCXXABI : public CXXABI { |
| protected: |
| ASTContext &Context; |
| public: |
| ItaniumCXXABI(ASTContext &Ctx) : Context(Ctx) { } |
| |
| std::pair<uint64_t, unsigned> |
| getMemberPointerWidthAndAlign(const MemberPointerType *MPT) const { |
| const TargetInfo &Target = Context.getTargetInfo(); |
| TargetInfo::IntType PtrDiff = Target.getPtrDiffType(0); |
| uint64_t Width = Target.getTypeWidth(PtrDiff); |
| unsigned Align = Target.getTypeAlign(PtrDiff); |
| if (MPT->getPointeeType()->isFunctionType()) |
| Width = 2 * Width; |
| return std::make_pair(Width, Align); |
| } |
| |
| CallingConv getDefaultMethodCallConv(bool isVariadic) const { |
| return CC_C; |
| } |
| |
| // We cheat and just check that the class has a vtable pointer, and that it's |
| // only big enough to have a vtable pointer and nothing more (or less). |
| bool isNearlyEmpty(const CXXRecordDecl *RD) const { |
| |
| // Check that the class has a vtable pointer. |
| if (!RD->isDynamicClass()) |
| return false; |
| |
| const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD); |
| CharUnits PointerSize = |
| Context.toCharUnitsFromBits(Context.getTargetInfo().getPointerWidth(0)); |
| return Layout.getNonVirtualSize() == PointerSize; |
| } |
| |
| virtual MangleNumberingContext *createMangleNumberingContext() const { |
| return new ItaniumNumberingContext(); |
| } |
| }; |
| |
| class ARMCXXABI : public ItaniumCXXABI { |
| public: |
| ARMCXXABI(ASTContext &Ctx) : ItaniumCXXABI(Ctx) { } |
| }; |
| } |
| |
| CXXABI *clang::CreateItaniumCXXABI(ASTContext &Ctx) { |
| return new ItaniumCXXABI(Ctx); |
| } |
| |
| CXXABI *clang::CreateARMCXXABI(ASTContext &Ctx) { |
| return new ARMCXXABI(Ctx); |
| } |