| //===--- Mangle.cpp - Mangle C++ Names --------------------------*- C++ -*-===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // Implements generic name mangling support for blocks and Objective-C. |
| // |
| //===----------------------------------------------------------------------===// |
| #include "clang/AST/Attr.h" |
| #include "clang/AST/ASTContext.h" |
| #include "clang/AST/Decl.h" |
| #include "clang/AST/DeclCXX.h" |
| #include "clang/AST/DeclObjC.h" |
| #include "clang/AST/DeclTemplate.h" |
| #include "clang/AST/ExprCXX.h" |
| #include "clang/AST/Mangle.h" |
| #include "clang/AST/VTableBuilder.h" |
| #include "clang/Basic/ABI.h" |
| #include "clang/Basic/SourceManager.h" |
| #include "clang/Basic/TargetInfo.h" |
| #include "llvm/ADT/StringExtras.h" |
| #include "llvm/IR/DataLayout.h" |
| #include "llvm/IR/Mangler.h" |
| #include "llvm/Support/ErrorHandling.h" |
| #include "llvm/Support/raw_ostream.h" |
| |
| using namespace clang; |
| |
| // FIXME: For blocks we currently mimic GCC's mangling scheme, which leaves |
| // much to be desired. Come up with a better mangling scheme. |
| |
| static void mangleFunctionBlock(MangleContext &Context, |
| StringRef Outer, |
| const BlockDecl *BD, |
| raw_ostream &Out) { |
| unsigned discriminator = Context.getBlockId(BD, true); |
| if (discriminator == 0) |
| Out << "__" << Outer << "_block_invoke"; |
| else |
| Out << "__" << Outer << "_block_invoke_" << discriminator+1; |
| } |
| |
| void MangleContext::anchor() { } |
| |
| enum CCMangling { |
| CCM_Other, |
| CCM_Fast, |
| CCM_RegCall, |
| CCM_Vector, |
| CCM_Std |
| }; |
| |
| static bool isExternC(const NamedDecl *ND) { |
| if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(ND)) |
| return FD->isExternC(); |
| return cast<VarDecl>(ND)->isExternC(); |
| } |
| |
| static CCMangling getCallingConvMangling(const ASTContext &Context, |
| const NamedDecl *ND) { |
| const TargetInfo &TI = Context.getTargetInfo(); |
| const llvm::Triple &Triple = TI.getTriple(); |
| if (!Triple.isOSWindows() || |
| !(Triple.getArch() == llvm::Triple::x86 || |
| Triple.getArch() == llvm::Triple::x86_64)) |
| return CCM_Other; |
| |
| if (Context.getLangOpts().CPlusPlus && !isExternC(ND) && |
| TI.getCXXABI() == TargetCXXABI::Microsoft) |
| return CCM_Other; |
| |
| const FunctionDecl *FD = dyn_cast<FunctionDecl>(ND); |
| if (!FD) |
| return CCM_Other; |
| QualType T = FD->getType(); |
| |
| const FunctionType *FT = T->castAs<FunctionType>(); |
| |
| CallingConv CC = FT->getCallConv(); |
| switch (CC) { |
| default: |
| return CCM_Other; |
| case CC_X86FastCall: |
| return CCM_Fast; |
| case CC_X86StdCall: |
| return CCM_Std; |
| case CC_X86VectorCall: |
| return CCM_Vector; |
| } |
| } |
| |
| bool MangleContext::shouldMangleDeclName(const NamedDecl *D) { |
| const ASTContext &ASTContext = getASTContext(); |
| |
| CCMangling CC = getCallingConvMangling(ASTContext, D); |
| if (CC != CCM_Other) |
| return true; |
| |
| // If the declaration has an owning module for linkage purposes that needs to |
| // be mangled, we must mangle its name. |
| if (!D->hasExternalFormalLinkage() && D->getOwningModuleForLinkage()) |
| return true; |
| |
| // In C, functions with no attributes never need to be mangled. Fastpath them. |
| if (!getASTContext().getLangOpts().CPlusPlus && !D->hasAttrs()) |
| return false; |
| |
| // Any decl can be declared with __asm("foo") on it, and this takes precedence |
| // over all other naming in the .o file. |
| if (D->hasAttr<AsmLabelAttr>()) |
| return true; |
| |
| return shouldMangleCXXName(D); |
| } |
| |
| void MangleContext::mangleName(const NamedDecl *D, raw_ostream &Out) { |
| // Any decl can be declared with __asm("foo") on it, and this takes precedence |
| // over all other naming in the .o file. |
| if (const AsmLabelAttr *ALA = D->getAttr<AsmLabelAttr>()) { |
| // If we have an asm name, then we use it as the mangling. |
| |
| // If the label isn't literal, or if this is an alias for an LLVM intrinsic, |
| // do not add a "\01" prefix. |
| if (!ALA->getIsLiteralLabel() || ALA->getLabel().startswith("llvm.")) { |
| Out << ALA->getLabel(); |
| return; |
| } |
| |
| // Adding the prefix can cause problems when one file has a "foo" and |
| // another has a "\01foo". That is known to happen on ELF with the |
| // tricks normally used for producing aliases (PR9177). Fortunately the |
| // llvm mangler on ELF is a nop, so we can just avoid adding the \01 |
| // marker. |
| char GlobalPrefix = |
| getASTContext().getTargetInfo().getDataLayout().getGlobalPrefix(); |
| if (GlobalPrefix) |
| Out << '\01'; // LLVM IR Marker for __asm("foo") |
| |
| Out << ALA->getLabel(); |
| return; |
| } |
| |
| const ASTContext &ASTContext = getASTContext(); |
| CCMangling CC = getCallingConvMangling(ASTContext, D); |
| bool MCXX = shouldMangleCXXName(D); |
| const TargetInfo &TI = Context.getTargetInfo(); |
| if (CC == CCM_Other || (MCXX && TI.getCXXABI() == TargetCXXABI::Microsoft)) { |
| if (const ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(D)) |
| mangleObjCMethodName(OMD, Out); |
| else |
| mangleCXXName(D, Out); |
| return; |
| } |
| |
| Out << '\01'; |
| if (CC == CCM_Std) |
| Out << '_'; |
| else if (CC == CCM_Fast) |
| Out << '@'; |
| else if (CC == CCM_RegCall) |
| Out << "__regcall3__"; |
| |
| if (!MCXX) |
| Out << D->getIdentifier()->getName(); |
| else if (const ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(D)) |
| mangleObjCMethodName(OMD, Out); |
| else |
| mangleCXXName(D, Out); |
| |
| const FunctionDecl *FD = cast<FunctionDecl>(D); |
| const FunctionType *FT = FD->getType()->castAs<FunctionType>(); |
| const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FT); |
| if (CC == CCM_Vector) |
| Out << '@'; |
| Out << '@'; |
| if (!Proto) { |
| Out << '0'; |
| return; |
| } |
| assert(!Proto->isVariadic()); |
| unsigned ArgWords = 0; |
| if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) |
| if (!MD->isStatic()) |
| ++ArgWords; |
| for (const auto &AT : Proto->param_types()) |
| // Size should be aligned to pointer size. |
| ArgWords += |
| llvm::alignTo(ASTContext.getTypeSize(AT), TI.getPointerWidth(0)) / |
| TI.getPointerWidth(0); |
| Out << ((TI.getPointerWidth(0) / 8) * ArgWords); |
| } |
| |
| void MangleContext::mangleGlobalBlock(const BlockDecl *BD, |
| const NamedDecl *ID, |
| raw_ostream &Out) { |
| unsigned discriminator = getBlockId(BD, false); |
| if (ID) { |
| if (shouldMangleDeclName(ID)) |
| mangleName(ID, Out); |
| else { |
| Out << ID->getIdentifier()->getName(); |
| } |
| } |
| if (discriminator == 0) |
| Out << "_block_invoke"; |
| else |
| Out << "_block_invoke_" << discriminator+1; |
| } |
| |
| void MangleContext::mangleCtorBlock(const CXXConstructorDecl *CD, |
| CXXCtorType CT, const BlockDecl *BD, |
| raw_ostream &ResStream) { |
| SmallString<64> Buffer; |
| llvm::raw_svector_ostream Out(Buffer); |
| mangleCXXCtor(CD, CT, Out); |
| mangleFunctionBlock(*this, Buffer, BD, ResStream); |
| } |
| |
| void MangleContext::mangleDtorBlock(const CXXDestructorDecl *DD, |
| CXXDtorType DT, const BlockDecl *BD, |
| raw_ostream &ResStream) { |
| SmallString<64> Buffer; |
| llvm::raw_svector_ostream Out(Buffer); |
| mangleCXXDtor(DD, DT, Out); |
| mangleFunctionBlock(*this, Buffer, BD, ResStream); |
| } |
| |
| void MangleContext::mangleBlock(const DeclContext *DC, const BlockDecl *BD, |
| raw_ostream &Out) { |
| assert(!isa<CXXConstructorDecl>(DC) && !isa<CXXDestructorDecl>(DC)); |
| |
| SmallString<64> Buffer; |
| llvm::raw_svector_ostream Stream(Buffer); |
| if (const ObjCMethodDecl *Method = dyn_cast<ObjCMethodDecl>(DC)) { |
| mangleObjCMethodName(Method, Stream); |
| } else { |
| assert((isa<NamedDecl>(DC) || isa<BlockDecl>(DC)) && |
| "expected a NamedDecl or BlockDecl"); |
| if (isa<BlockDecl>(DC)) |
| for (; DC && isa<BlockDecl>(DC); DC = DC->getParent()) |
| (void) getBlockId(cast<BlockDecl>(DC), true); |
| assert((isa<TranslationUnitDecl>(DC) || isa<NamedDecl>(DC)) && |
| "expected a TranslationUnitDecl or a NamedDecl"); |
| if (const auto *CD = dyn_cast<CXXConstructorDecl>(DC)) |
| mangleCtorBlock(CD, /*CT*/ Ctor_Complete, BD, Out); |
| else if (const auto *DD = dyn_cast<CXXDestructorDecl>(DC)) |
| mangleDtorBlock(DD, /*DT*/ Dtor_Complete, BD, Out); |
| else if (auto ND = dyn_cast<NamedDecl>(DC)) { |
| if (!shouldMangleDeclName(ND) && ND->getIdentifier()) |
| Stream << ND->getIdentifier()->getName(); |
| else { |
| // FIXME: We were doing a mangleUnqualifiedName() before, but that's |
| // a private member of a class that will soon itself be private to the |
| // Itanium C++ ABI object. What should we do now? Right now, I'm just |
| // calling the mangleName() method on the MangleContext; is there a |
| // better way? |
| mangleName(ND, Stream); |
| } |
| } |
| } |
| mangleFunctionBlock(*this, Buffer, BD, Out); |
| } |
| |
| void MangleContext::mangleObjCMethodNameWithoutSize(const ObjCMethodDecl *MD, |
| raw_ostream &OS) { |
| const ObjCContainerDecl *CD = |
| dyn_cast<ObjCContainerDecl>(MD->getDeclContext()); |
| assert (CD && "Missing container decl in GetNameForMethod"); |
| OS << (MD->isInstanceMethod() ? '-' : '+') << '['; |
| if (const ObjCCategoryImplDecl *CID = dyn_cast<ObjCCategoryImplDecl>(CD)) { |
| OS << CID->getClassInterface()->getName(); |
| OS << '(' << *CID << ')'; |
| } else { |
| OS << CD->getName(); |
| } |
| OS << ' '; |
| MD->getSelector().print(OS); |
| OS << ']'; |
| } |
| |
| void MangleContext::mangleObjCMethodName(const ObjCMethodDecl *MD, |
| raw_ostream &Out) { |
| SmallString<64> Name; |
| llvm::raw_svector_ostream OS(Name); |
| |
| mangleObjCMethodNameWithoutSize(MD, OS); |
| Out << OS.str().size() << OS.str(); |
| } |
| |
| class ASTNameGenerator::Implementation { |
| std::unique_ptr<MangleContext> MC; |
| llvm::DataLayout DL; |
| |
| public: |
| explicit Implementation(ASTContext &Ctx) |
| : MC(Ctx.createMangleContext()), DL(Ctx.getTargetInfo().getDataLayout()) { |
| } |
| |
| bool writeName(const Decl *D, raw_ostream &OS) { |
| // First apply frontend mangling. |
| SmallString<128> FrontendBuf; |
| llvm::raw_svector_ostream FrontendBufOS(FrontendBuf); |
| if (auto *FD = dyn_cast<FunctionDecl>(D)) { |
| if (FD->isDependentContext()) |
| return true; |
| if (writeFuncOrVarName(FD, FrontendBufOS)) |
| return true; |
| } else if (auto *VD = dyn_cast<VarDecl>(D)) { |
| if (writeFuncOrVarName(VD, FrontendBufOS)) |
| return true; |
| } else if (auto *MD = dyn_cast<ObjCMethodDecl>(D)) { |
| MC->mangleObjCMethodNameWithoutSize(MD, OS); |
| return false; |
| } else if (auto *ID = dyn_cast<ObjCInterfaceDecl>(D)) { |
| writeObjCClassName(ID, FrontendBufOS); |
| } else { |
| return true; |
| } |
| |
| // Now apply backend mangling. |
| llvm::Mangler::getNameWithPrefix(OS, FrontendBufOS.str(), DL); |
| return false; |
| } |
| |
| std::string getName(const Decl *D) { |
| std::string Name; |
| { |
| llvm::raw_string_ostream OS(Name); |
| writeName(D, OS); |
| } |
| return Name; |
| } |
| |
| enum ObjCKind { |
| ObjCClass, |
| ObjCMetaclass, |
| }; |
| |
| static StringRef getClassSymbolPrefix(ObjCKind Kind, |
| const ASTContext &Context) { |
| if (Context.getLangOpts().ObjCRuntime.isGNUFamily()) |
| return Kind == ObjCMetaclass ? "_OBJC_METACLASS_" : "_OBJC_CLASS_"; |
| return Kind == ObjCMetaclass ? "OBJC_METACLASS_$_" : "OBJC_CLASS_$_"; |
| } |
| |
| std::vector<std::string> getAllManglings(const ObjCContainerDecl *OCD) { |
| StringRef ClassName; |
| if (const auto *OID = dyn_cast<ObjCInterfaceDecl>(OCD)) |
| ClassName = OID->getObjCRuntimeNameAsString(); |
| else if (const auto *OID = dyn_cast<ObjCImplementationDecl>(OCD)) |
| ClassName = OID->getObjCRuntimeNameAsString(); |
| |
| if (ClassName.empty()) |
| return {}; |
| |
| auto Mangle = [&](ObjCKind Kind, StringRef ClassName) -> std::string { |
| SmallString<40> Mangled; |
| auto Prefix = getClassSymbolPrefix(Kind, OCD->getASTContext()); |
| llvm::Mangler::getNameWithPrefix(Mangled, Prefix + ClassName, DL); |
| return Mangled.str(); |
| }; |
| |
| return { |
| Mangle(ObjCClass, ClassName), |
| Mangle(ObjCMetaclass, ClassName), |
| }; |
| } |
| |
| std::vector<std::string> getAllManglings(const Decl *D) { |
| if (const auto *OCD = dyn_cast<ObjCContainerDecl>(D)) |
| return getAllManglings(OCD); |
| |
| if (!(isa<CXXRecordDecl>(D) || isa<CXXMethodDecl>(D))) |
| return {}; |
| |
| const NamedDecl *ND = cast<NamedDecl>(D); |
| |
| ASTContext &Ctx = ND->getASTContext(); |
| std::unique_ptr<MangleContext> M(Ctx.createMangleContext()); |
| |
| std::vector<std::string> Manglings; |
| |
| auto hasDefaultCXXMethodCC = [](ASTContext &C, const CXXMethodDecl *MD) { |
| auto DefaultCC = C.getDefaultCallingConvention(/*IsVariadic=*/false, |
| /*IsCXXMethod=*/true); |
| auto CC = MD->getType()->castAs<FunctionProtoType>()->getCallConv(); |
| return CC == DefaultCC; |
| }; |
| |
| if (const auto *CD = dyn_cast_or_null<CXXConstructorDecl>(ND)) { |
| Manglings.emplace_back(getMangledStructor(CD, Ctor_Base)); |
| |
| if (Ctx.getTargetInfo().getCXXABI().isItaniumFamily()) |
| if (!CD->getParent()->isAbstract()) |
| Manglings.emplace_back(getMangledStructor(CD, Ctor_Complete)); |
| |
| if (Ctx.getTargetInfo().getCXXABI().isMicrosoft()) |
| if (CD->hasAttr<DLLExportAttr>() && CD->isDefaultConstructor()) |
| if (!(hasDefaultCXXMethodCC(Ctx, CD) && CD->getNumParams() == 0)) |
| Manglings.emplace_back(getMangledStructor(CD, Ctor_DefaultClosure)); |
| } else if (const auto *DD = dyn_cast_or_null<CXXDestructorDecl>(ND)) { |
| Manglings.emplace_back(getMangledStructor(DD, Dtor_Base)); |
| if (Ctx.getTargetInfo().getCXXABI().isItaniumFamily()) { |
| Manglings.emplace_back(getMangledStructor(DD, Dtor_Complete)); |
| if (DD->isVirtual()) |
| Manglings.emplace_back(getMangledStructor(DD, Dtor_Deleting)); |
| } |
| } else if (const auto *MD = dyn_cast_or_null<CXXMethodDecl>(ND)) { |
| Manglings.emplace_back(getName(ND)); |
| if (MD->isVirtual()) |
| if (const auto *TIV = Ctx.getVTableContext()->getThunkInfo(MD)) |
| for (const auto &T : *TIV) |
| Manglings.emplace_back(getMangledThunk(MD, T)); |
| } |
| |
| return Manglings; |
| } |
| |
| private: |
| bool writeFuncOrVarName(const NamedDecl *D, raw_ostream &OS) { |
| if (MC->shouldMangleDeclName(D)) { |
| if (const auto *CtorD = dyn_cast<CXXConstructorDecl>(D)) |
| MC->mangleCXXCtor(CtorD, Ctor_Complete, OS); |
| else if (const auto *DtorD = dyn_cast<CXXDestructorDecl>(D)) |
| MC->mangleCXXDtor(DtorD, Dtor_Complete, OS); |
| else |
| MC->mangleName(D, OS); |
| return false; |
| } else { |
| IdentifierInfo *II = D->getIdentifier(); |
| if (!II) |
| return true; |
| OS << II->getName(); |
| return false; |
| } |
| } |
| |
| void writeObjCClassName(const ObjCInterfaceDecl *D, raw_ostream &OS) { |
| OS << getClassSymbolPrefix(ObjCClass, D->getASTContext()); |
| OS << D->getObjCRuntimeNameAsString(); |
| } |
| |
| std::string getMangledStructor(const NamedDecl *ND, unsigned StructorType) { |
| std::string FrontendBuf; |
| llvm::raw_string_ostream FOS(FrontendBuf); |
| |
| if (const auto *CD = dyn_cast_or_null<CXXConstructorDecl>(ND)) |
| MC->mangleCXXCtor(CD, static_cast<CXXCtorType>(StructorType), FOS); |
| else if (const auto *DD = dyn_cast_or_null<CXXDestructorDecl>(ND)) |
| MC->mangleCXXDtor(DD, static_cast<CXXDtorType>(StructorType), FOS); |
| |
| std::string BackendBuf; |
| llvm::raw_string_ostream BOS(BackendBuf); |
| |
| llvm::Mangler::getNameWithPrefix(BOS, FOS.str(), DL); |
| |
| return BOS.str(); |
| } |
| |
| std::string getMangledThunk(const CXXMethodDecl *MD, const ThunkInfo &T) { |
| std::string FrontendBuf; |
| llvm::raw_string_ostream FOS(FrontendBuf); |
| |
| MC->mangleThunk(MD, T, FOS); |
| |
| std::string BackendBuf; |
| llvm::raw_string_ostream BOS(BackendBuf); |
| |
| llvm::Mangler::getNameWithPrefix(BOS, FOS.str(), DL); |
| |
| return BOS.str(); |
| } |
| }; |
| |
| ASTNameGenerator::ASTNameGenerator(ASTContext &Ctx) |
| : Impl(std::make_unique<Implementation>(Ctx)) {} |
| |
| ASTNameGenerator::~ASTNameGenerator() {} |
| |
| bool ASTNameGenerator::writeName(const Decl *D, raw_ostream &OS) { |
| return Impl->writeName(D, OS); |
| } |
| |
| std::string ASTNameGenerator::getName(const Decl *D) { |
| return Impl->getName(D); |
| } |
| |
| std::vector<std::string> ASTNameGenerator::getAllManglings(const Decl *D) { |
| return Impl->getAllManglings(D); |
| } |