| //===--- CGDeclCXX.cpp - Emit LLVM Code for C++ declarations --------------===// |
| // |
| // 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 |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This contains code dealing with code generation of C++ declarations |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "CGCXXABI.h" |
| #include "CGHLSLRuntime.h" |
| #include "CGObjCRuntime.h" |
| #include "CGOpenMPRuntime.h" |
| #include "CodeGenFunction.h" |
| #include "TargetInfo.h" |
| #include "clang/AST/Attr.h" |
| #include "clang/Basic/LangOptions.h" |
| #include "llvm/ADT/StringExtras.h" |
| #include "llvm/IR/Intrinsics.h" |
| #include "llvm/IR/MDBuilder.h" |
| #include "llvm/Support/Path.h" |
| |
| using namespace clang; |
| using namespace CodeGen; |
| |
| static void EmitDeclInit(CodeGenFunction &CGF, const VarDecl &D, |
| ConstantAddress DeclPtr) { |
| assert( |
| (D.hasGlobalStorage() || |
| (D.hasLocalStorage() && CGF.getContext().getLangOpts().OpenCLCPlusPlus)) && |
| "VarDecl must have global or local (in the case of OpenCL) storage!"); |
| assert(!D.getType()->isReferenceType() && |
| "Should not call EmitDeclInit on a reference!"); |
| |
| QualType type = D.getType(); |
| LValue lv = CGF.MakeAddrLValue(DeclPtr, type); |
| |
| const Expr *Init = D.getInit(); |
| switch (CGF.getEvaluationKind(type)) { |
| case TEK_Scalar: { |
| CodeGenModule &CGM = CGF.CGM; |
| if (lv.isObjCStrong()) |
| CGM.getObjCRuntime().EmitObjCGlobalAssign(CGF, CGF.EmitScalarExpr(Init), |
| DeclPtr, D.getTLSKind()); |
| else if (lv.isObjCWeak()) |
| CGM.getObjCRuntime().EmitObjCWeakAssign(CGF, CGF.EmitScalarExpr(Init), |
| DeclPtr); |
| else |
| CGF.EmitScalarInit(Init, &D, lv, false); |
| return; |
| } |
| case TEK_Complex: |
| CGF.EmitComplexExprIntoLValue(Init, lv, /*isInit*/ true); |
| return; |
| case TEK_Aggregate: |
| CGF.EmitAggExpr(Init, |
| AggValueSlot::forLValue(lv, CGF, AggValueSlot::IsDestructed, |
| AggValueSlot::DoesNotNeedGCBarriers, |
| AggValueSlot::IsNotAliased, |
| AggValueSlot::DoesNotOverlap)); |
| return; |
| } |
| llvm_unreachable("bad evaluation kind"); |
| } |
| |
| /// Emit code to cause the destruction of the given variable with |
| /// static storage duration. |
| static void EmitDeclDestroy(CodeGenFunction &CGF, const VarDecl &D, |
| ConstantAddress Addr) { |
| // Honor __attribute__((no_destroy)) and bail instead of attempting |
| // to emit a reference to a possibly nonexistent destructor, which |
| // in turn can cause a crash. This will result in a global constructor |
| // that isn't balanced out by a destructor call as intended by the |
| // attribute. This also checks for -fno-c++-static-destructors and |
| // bails even if the attribute is not present. |
| QualType::DestructionKind DtorKind = D.needsDestruction(CGF.getContext()); |
| |
| // FIXME: __attribute__((cleanup)) ? |
| |
| switch (DtorKind) { |
| case QualType::DK_none: |
| return; |
| |
| case QualType::DK_cxx_destructor: |
| break; |
| |
| case QualType::DK_objc_strong_lifetime: |
| case QualType::DK_objc_weak_lifetime: |
| case QualType::DK_nontrivial_c_struct: |
| // We don't care about releasing objects during process teardown. |
| assert(!D.getTLSKind() && "should have rejected this"); |
| return; |
| } |
| |
| llvm::FunctionCallee Func; |
| llvm::Constant *Argument; |
| |
| CodeGenModule &CGM = CGF.CGM; |
| QualType Type = D.getType(); |
| |
| // Special-case non-array C++ destructors, if they have the right signature. |
| // Under some ABIs, destructors return this instead of void, and cannot be |
| // passed directly to __cxa_atexit if the target does not allow this |
| // mismatch. |
| const CXXRecordDecl *Record = Type->getAsCXXRecordDecl(); |
| bool CanRegisterDestructor = |
| Record && (!CGM.getCXXABI().HasThisReturn( |
| GlobalDecl(Record->getDestructor(), Dtor_Complete)) || |
| CGM.getCXXABI().canCallMismatchedFunctionType()); |
| // If __cxa_atexit is disabled via a flag, a different helper function is |
| // generated elsewhere which uses atexit instead, and it takes the destructor |
| // directly. |
| bool UsingExternalHelper = !CGM.getCodeGenOpts().CXAAtExit; |
| if (Record && (CanRegisterDestructor || UsingExternalHelper)) { |
| assert(!Record->hasTrivialDestructor()); |
| CXXDestructorDecl *Dtor = Record->getDestructor(); |
| |
| Func = CGM.getAddrAndTypeOfCXXStructor(GlobalDecl(Dtor, Dtor_Complete)); |
| if (CGF.getContext().getLangOpts().OpenCL) { |
| auto DestAS = |
| CGM.getTargetCodeGenInfo().getAddrSpaceOfCxaAtexitPtrParam(); |
| auto DestTy = llvm::PointerType::get( |
| CGM.getLLVMContext(), CGM.getContext().getTargetAddressSpace(DestAS)); |
| auto SrcAS = D.getType().getQualifiers().getAddressSpace(); |
| if (DestAS == SrcAS) |
| Argument = Addr.getPointer(); |
| else |
| // FIXME: On addr space mismatch we are passing NULL. The generation |
| // of the global destructor function should be adjusted accordingly. |
| Argument = llvm::ConstantPointerNull::get(DestTy); |
| } else { |
| Argument = Addr.getPointer(); |
| } |
| // Otherwise, the standard logic requires a helper function. |
| } else { |
| Addr = Addr.withElementType(CGF.ConvertTypeForMem(Type)); |
| Func = CodeGenFunction(CGM) |
| .generateDestroyHelper(Addr, Type, CGF.getDestroyer(DtorKind), |
| CGF.needsEHCleanup(DtorKind), &D); |
| Argument = llvm::Constant::getNullValue(CGF.Int8PtrTy); |
| } |
| |
| CGM.getCXXABI().registerGlobalDtor(CGF, D, Func, Argument); |
| } |
| |
| /// Emit code to cause the variable at the given address to be considered as |
| /// constant from this point onwards. |
| static void EmitDeclInvariant(CodeGenFunction &CGF, const VarDecl &D, |
| llvm::Constant *Addr) { |
| return CGF.EmitInvariantStart( |
| Addr, CGF.getContext().getTypeSizeInChars(D.getType())); |
| } |
| |
| void CodeGenFunction::EmitInvariantStart(llvm::Constant *Addr, CharUnits Size) { |
| // Do not emit the intrinsic if we're not optimizing. |
| if (!CGM.getCodeGenOpts().OptimizationLevel) |
| return; |
| |
| // Grab the llvm.invariant.start intrinsic. |
| llvm::Intrinsic::ID InvStartID = llvm::Intrinsic::invariant_start; |
| // Overloaded address space type. |
| llvm::Type *ObjectPtr[1] = {Int8PtrTy}; |
| llvm::Function *InvariantStart = CGM.getIntrinsic(InvStartID, ObjectPtr); |
| |
| // Emit a call with the size in bytes of the object. |
| uint64_t Width = Size.getQuantity(); |
| llvm::Value *Args[2] = {llvm::ConstantInt::getSigned(Int64Ty, Width), Addr}; |
| Builder.CreateCall(InvariantStart, Args); |
| } |
| |
| void CodeGenFunction::EmitCXXGlobalVarDeclInit(const VarDecl &D, |
| llvm::GlobalVariable *GV, |
| bool PerformInit) { |
| |
| const Expr *Init = D.getInit(); |
| QualType T = D.getType(); |
| |
| // The address space of a static local variable (DeclPtr) may be different |
| // from the address space of the "this" argument of the constructor. In that |
| // case, we need an addrspacecast before calling the constructor. |
| // |
| // struct StructWithCtor { |
| // __device__ StructWithCtor() {...} |
| // }; |
| // __device__ void foo() { |
| // __shared__ StructWithCtor s; |
| // ... |
| // } |
| // |
| // For example, in the above CUDA code, the static local variable s has a |
| // "shared" address space qualifier, but the constructor of StructWithCtor |
| // expects "this" in the "generic" address space. |
| unsigned ExpectedAddrSpace = getTypes().getTargetAddressSpace(T); |
| unsigned ActualAddrSpace = GV->getAddressSpace(); |
| llvm::Constant *DeclPtr = GV; |
| if (ActualAddrSpace != ExpectedAddrSpace) { |
| llvm::PointerType *PTy = |
| llvm::PointerType::get(getLLVMContext(), ExpectedAddrSpace); |
| DeclPtr = llvm::ConstantExpr::getAddrSpaceCast(DeclPtr, PTy); |
| } |
| |
| ConstantAddress DeclAddr( |
| DeclPtr, GV->getValueType(), getContext().getDeclAlign(&D)); |
| |
| if (!T->isReferenceType()) { |
| if (getLangOpts().OpenMP && !getLangOpts().OpenMPSimd && |
| D.hasAttr<OMPThreadPrivateDeclAttr>()) { |
| (void)CGM.getOpenMPRuntime().emitThreadPrivateVarDefinition( |
| &D, DeclAddr, D.getAttr<OMPThreadPrivateDeclAttr>()->getLocation(), |
| PerformInit, this); |
| } |
| bool NeedsDtor = |
| D.needsDestruction(getContext()) == QualType::DK_cxx_destructor; |
| if (PerformInit) |
| EmitDeclInit(*this, D, DeclAddr); |
| if (D.getType().isConstantStorage(getContext(), true, !NeedsDtor)) |
| EmitDeclInvariant(*this, D, DeclPtr); |
| else |
| EmitDeclDestroy(*this, D, DeclAddr); |
| return; |
| } |
| |
| assert(PerformInit && "cannot have constant initializer which needs " |
| "destruction for reference"); |
| RValue RV = EmitReferenceBindingToExpr(Init); |
| EmitStoreOfScalar(RV.getScalarVal(), DeclAddr, false, T); |
| } |
| |
| /// Create a stub function, suitable for being passed to atexit, |
| /// which passes the given address to the given destructor function. |
| llvm::Function *CodeGenFunction::createAtExitStub(const VarDecl &VD, |
| llvm::FunctionCallee dtor, |
| llvm::Constant *addr) { |
| // Get the destructor function type, void(*)(void). |
| llvm::FunctionType *ty = llvm::FunctionType::get(CGM.VoidTy, false); |
| SmallString<256> FnName; |
| { |
| llvm::raw_svector_ostream Out(FnName); |
| CGM.getCXXABI().getMangleContext().mangleDynamicAtExitDestructor(&VD, Out); |
| } |
| |
| const CGFunctionInfo &FI = CGM.getTypes().arrangeNullaryFunction(); |
| llvm::Function *fn = CGM.CreateGlobalInitOrCleanUpFunction( |
| ty, FnName.str(), FI, VD.getLocation()); |
| |
| CodeGenFunction CGF(CGM); |
| |
| CGF.StartFunction(GlobalDecl(&VD, DynamicInitKind::AtExit), |
| CGM.getContext().VoidTy, fn, FI, FunctionArgList(), |
| VD.getLocation(), VD.getInit()->getExprLoc()); |
| // Emit an artificial location for this function. |
| auto AL = ApplyDebugLocation::CreateArtificial(CGF); |
| |
| llvm::CallInst *call = CGF.Builder.CreateCall(dtor, addr); |
| |
| // Make sure the call and the callee agree on calling convention. |
| if (auto *dtorFn = dyn_cast<llvm::Function>( |
| dtor.getCallee()->stripPointerCastsAndAliases())) |
| call->setCallingConv(dtorFn->getCallingConv()); |
| |
| CGF.FinishFunction(); |
| |
| return fn; |
| } |
| |
| /// Create a stub function, suitable for being passed to __pt_atexit_np, |
| /// which passes the given address to the given destructor function. |
| llvm::Function *CodeGenFunction::createTLSAtExitStub( |
| const VarDecl &D, llvm::FunctionCallee Dtor, llvm::Constant *Addr, |
| llvm::FunctionCallee &AtExit) { |
| SmallString<256> FnName; |
| { |
| llvm::raw_svector_ostream Out(FnName); |
| CGM.getCXXABI().getMangleContext().mangleDynamicAtExitDestructor(&D, Out); |
| } |
| |
| const CGFunctionInfo &FI = CGM.getTypes().arrangeLLVMFunctionInfo( |
| getContext().IntTy, FnInfoOpts::None, {getContext().IntTy}, |
| FunctionType::ExtInfo(), {}, RequiredArgs::All); |
| |
| // Get the stub function type, int(*)(int,...). |
| llvm::FunctionType *StubTy = |
| llvm::FunctionType::get(CGM.IntTy, {CGM.IntTy}, true); |
| |
| llvm::Function *DtorStub = CGM.CreateGlobalInitOrCleanUpFunction( |
| StubTy, FnName.str(), FI, D.getLocation()); |
| |
| CodeGenFunction CGF(CGM); |
| |
| FunctionArgList Args; |
| ImplicitParamDecl IPD(CGM.getContext(), CGM.getContext().IntTy, |
| ImplicitParamKind::Other); |
| Args.push_back(&IPD); |
| QualType ResTy = CGM.getContext().IntTy; |
| |
| CGF.StartFunction(GlobalDecl(&D, DynamicInitKind::AtExit), ResTy, DtorStub, |
| FI, Args, D.getLocation(), D.getInit()->getExprLoc()); |
| |
| // Emit an artificial location for this function. |
| auto AL = ApplyDebugLocation::CreateArtificial(CGF); |
| |
| llvm::CallInst *call = CGF.Builder.CreateCall(Dtor, Addr); |
| |
| // Make sure the call and the callee agree on calling convention. |
| if (auto *DtorFn = dyn_cast<llvm::Function>( |
| Dtor.getCallee()->stripPointerCastsAndAliases())) |
| call->setCallingConv(DtorFn->getCallingConv()); |
| |
| // Return 0 from function |
| CGF.Builder.CreateStore(llvm::Constant::getNullValue(CGM.IntTy), |
| CGF.ReturnValue); |
| |
| CGF.FinishFunction(); |
| |
| return DtorStub; |
| } |
| |
| /// Register a global destructor using the C atexit runtime function. |
| void CodeGenFunction::registerGlobalDtorWithAtExit(const VarDecl &VD, |
| llvm::FunctionCallee dtor, |
| llvm::Constant *addr) { |
| // Create a function which calls the destructor. |
| llvm::Constant *dtorStub = createAtExitStub(VD, dtor, addr); |
| registerGlobalDtorWithAtExit(dtorStub); |
| } |
| |
| /// Register a global destructor using the LLVM 'llvm.global_dtors' global. |
| void CodeGenFunction::registerGlobalDtorWithLLVM(const VarDecl &VD, |
| llvm::FunctionCallee Dtor, |
| llvm::Constant *Addr) { |
| // Create a function which calls the destructor. |
| llvm::Function *dtorStub = createAtExitStub(VD, Dtor, Addr); |
| CGM.AddGlobalDtor(dtorStub); |
| } |
| |
| void CodeGenFunction::registerGlobalDtorWithAtExit(llvm::Constant *dtorStub) { |
| // extern "C" int atexit(void (*f)(void)); |
| assert(dtorStub->getType() == |
| llvm::PointerType::get( |
| llvm::FunctionType::get(CGM.VoidTy, false), |
| dtorStub->getType()->getPointerAddressSpace()) && |
| "Argument to atexit has a wrong type."); |
| |
| llvm::FunctionType *atexitTy = |
| llvm::FunctionType::get(IntTy, dtorStub->getType(), false); |
| |
| llvm::FunctionCallee atexit = |
| CGM.CreateRuntimeFunction(atexitTy, "atexit", llvm::AttributeList(), |
| /*Local=*/true); |
| if (llvm::Function *atexitFn = dyn_cast<llvm::Function>(atexit.getCallee())) |
| atexitFn->setDoesNotThrow(); |
| |
| EmitNounwindRuntimeCall(atexit, dtorStub); |
| } |
| |
| llvm::Value * |
| CodeGenFunction::unregisterGlobalDtorWithUnAtExit(llvm::Constant *dtorStub) { |
| // The unatexit subroutine unregisters __dtor functions that were previously |
| // registered by the atexit subroutine. If the referenced function is found, |
| // it is removed from the list of functions that are called at normal program |
| // termination and the unatexit returns a value of 0, otherwise a non-zero |
| // value is returned. |
| // |
| // extern "C" int unatexit(void (*f)(void)); |
| assert(dtorStub->getType() == |
| llvm::PointerType::get( |
| llvm::FunctionType::get(CGM.VoidTy, false), |
| dtorStub->getType()->getPointerAddressSpace()) && |
| "Argument to unatexit has a wrong type."); |
| |
| llvm::FunctionType *unatexitTy = |
| llvm::FunctionType::get(IntTy, {dtorStub->getType()}, /*isVarArg=*/false); |
| |
| llvm::FunctionCallee unatexit = |
| CGM.CreateRuntimeFunction(unatexitTy, "unatexit", llvm::AttributeList()); |
| |
| cast<llvm::Function>(unatexit.getCallee())->setDoesNotThrow(); |
| |
| return EmitNounwindRuntimeCall(unatexit, dtorStub); |
| } |
| |
| void CodeGenFunction::EmitCXXGuardedInit(const VarDecl &D, |
| llvm::GlobalVariable *DeclPtr, |
| bool PerformInit) { |
| // If we've been asked to forbid guard variables, emit an error now. |
| // This diagnostic is hard-coded for Darwin's use case; we can find |
| // better phrasing if someone else needs it. |
| if (CGM.getCodeGenOpts().ForbidGuardVariables) |
| CGM.Error(D.getLocation(), |
| "this initialization requires a guard variable, which " |
| "the kernel does not support"); |
| |
| CGM.getCXXABI().EmitGuardedInit(*this, D, DeclPtr, PerformInit); |
| } |
| |
| void CodeGenFunction::EmitCXXGuardedInitBranch(llvm::Value *NeedsInit, |
| llvm::BasicBlock *InitBlock, |
| llvm::BasicBlock *NoInitBlock, |
| GuardKind Kind, |
| const VarDecl *D) { |
| assert((Kind == GuardKind::TlsGuard || D) && "no guarded variable"); |
| |
| // A guess at how many times we will enter the initialization of a |
| // variable, depending on the kind of variable. |
| static const uint64_t InitsPerTLSVar = 1024; |
| static const uint64_t InitsPerLocalVar = 1024 * 1024; |
| |
| llvm::MDNode *Weights; |
| if (Kind == GuardKind::VariableGuard && !D->isLocalVarDecl()) { |
| // For non-local variables, don't apply any weighting for now. Due to our |
| // use of COMDATs, we expect there to be at most one initialization of the |
| // variable per DSO, but we have no way to know how many DSOs will try to |
| // initialize the variable. |
| Weights = nullptr; |
| } else { |
| uint64_t NumInits; |
| // FIXME: For the TLS case, collect and use profiling information to |
| // determine a more accurate brach weight. |
| if (Kind == GuardKind::TlsGuard || D->getTLSKind()) |
| NumInits = InitsPerTLSVar; |
| else |
| NumInits = InitsPerLocalVar; |
| |
| // The probability of us entering the initializer is |
| // 1 / (total number of times we attempt to initialize the variable). |
| llvm::MDBuilder MDHelper(CGM.getLLVMContext()); |
| Weights = MDHelper.createBranchWeights(1, NumInits - 1); |
| } |
| |
| Builder.CreateCondBr(NeedsInit, InitBlock, NoInitBlock, Weights); |
| } |
| |
| llvm::Function *CodeGenModule::CreateGlobalInitOrCleanUpFunction( |
| llvm::FunctionType *FTy, const Twine &Name, const CGFunctionInfo &FI, |
| SourceLocation Loc, bool TLS, llvm::GlobalVariable::LinkageTypes Linkage) { |
| llvm::Function *Fn = llvm::Function::Create(FTy, Linkage, Name, &getModule()); |
| |
| if (!getLangOpts().AppleKext && !TLS) { |
| // Set the section if needed. |
| if (const char *Section = getTarget().getStaticInitSectionSpecifier()) |
| Fn->setSection(Section); |
| } |
| |
| if (Linkage == llvm::GlobalVariable::InternalLinkage) |
| SetInternalFunctionAttributes(GlobalDecl(), Fn, FI); |
| |
| Fn->setCallingConv(getRuntimeCC()); |
| |
| if (!getLangOpts().Exceptions) |
| Fn->setDoesNotThrow(); |
| |
| if (getLangOpts().Sanitize.has(SanitizerKind::Address) && |
| !isInNoSanitizeList(SanitizerKind::Address, Fn, Loc)) |
| Fn->addFnAttr(llvm::Attribute::SanitizeAddress); |
| |
| if (getLangOpts().Sanitize.has(SanitizerKind::KernelAddress) && |
| !isInNoSanitizeList(SanitizerKind::KernelAddress, Fn, Loc)) |
| Fn->addFnAttr(llvm::Attribute::SanitizeAddress); |
| |
| if (getLangOpts().Sanitize.has(SanitizerKind::HWAddress) && |
| !isInNoSanitizeList(SanitizerKind::HWAddress, Fn, Loc)) |
| Fn->addFnAttr(llvm::Attribute::SanitizeHWAddress); |
| |
| if (getLangOpts().Sanitize.has(SanitizerKind::KernelHWAddress) && |
| !isInNoSanitizeList(SanitizerKind::KernelHWAddress, Fn, Loc)) |
| Fn->addFnAttr(llvm::Attribute::SanitizeHWAddress); |
| |
| if (getLangOpts().Sanitize.has(SanitizerKind::MemtagStack) && |
| !isInNoSanitizeList(SanitizerKind::MemtagStack, Fn, Loc)) |
| Fn->addFnAttr(llvm::Attribute::SanitizeMemTag); |
| |
| if (getLangOpts().Sanitize.has(SanitizerKind::Thread) && |
| !isInNoSanitizeList(SanitizerKind::Thread, Fn, Loc)) |
| Fn->addFnAttr(llvm::Attribute::SanitizeThread); |
| |
| if (getLangOpts().Sanitize.has(SanitizerKind::Memory) && |
| !isInNoSanitizeList(SanitizerKind::Memory, Fn, Loc)) |
| Fn->addFnAttr(llvm::Attribute::SanitizeMemory); |
| |
| if (getLangOpts().Sanitize.has(SanitizerKind::KernelMemory) && |
| !isInNoSanitizeList(SanitizerKind::KernelMemory, Fn, Loc)) |
| Fn->addFnAttr(llvm::Attribute::SanitizeMemory); |
| |
| if (getLangOpts().Sanitize.has(SanitizerKind::SafeStack) && |
| !isInNoSanitizeList(SanitizerKind::SafeStack, Fn, Loc)) |
| Fn->addFnAttr(llvm::Attribute::SafeStack); |
| |
| if (getLangOpts().Sanitize.has(SanitizerKind::ShadowCallStack) && |
| !isInNoSanitizeList(SanitizerKind::ShadowCallStack, Fn, Loc)) |
| Fn->addFnAttr(llvm::Attribute::ShadowCallStack); |
| |
| return Fn; |
| } |
| |
| /// Create a global pointer to a function that will initialize a global |
| /// variable. The user has requested that this pointer be emitted in a specific |
| /// section. |
| void CodeGenModule::EmitPointerToInitFunc(const VarDecl *D, |
| llvm::GlobalVariable *GV, |
| llvm::Function *InitFunc, |
| InitSegAttr *ISA) { |
| llvm::GlobalVariable *PtrArray = new llvm::GlobalVariable( |
| TheModule, InitFunc->getType(), /*isConstant=*/true, |
| llvm::GlobalValue::PrivateLinkage, InitFunc, "__cxx_init_fn_ptr"); |
| PtrArray->setSection(ISA->getSection()); |
| addUsedGlobal(PtrArray); |
| |
| // If the GV is already in a comdat group, then we have to join it. |
| if (llvm::Comdat *C = GV->getComdat()) |
| PtrArray->setComdat(C); |
| } |
| |
| void |
| CodeGenModule::EmitCXXGlobalVarDeclInitFunc(const VarDecl *D, |
| llvm::GlobalVariable *Addr, |
| bool PerformInit) { |
| |
| // According to E.2.3.1 in CUDA-7.5 Programming guide: __device__, |
| // __constant__ and __shared__ variables defined in namespace scope, |
| // that are of class type, cannot have a non-empty constructor. All |
| // the checks have been done in Sema by now. Whatever initializers |
| // are allowed are empty and we just need to ignore them here. |
| if (getLangOpts().CUDAIsDevice && !getLangOpts().GPUAllowDeviceInit && |
| (D->hasAttr<CUDADeviceAttr>() || D->hasAttr<CUDAConstantAttr>() || |
| D->hasAttr<CUDASharedAttr>())) |
| return; |
| |
| // Check if we've already initialized this decl. |
| auto I = DelayedCXXInitPosition.find(D); |
| if (I != DelayedCXXInitPosition.end() && I->second == ~0U) |
| return; |
| |
| llvm::FunctionType *FTy = llvm::FunctionType::get(VoidTy, false); |
| SmallString<256> FnName; |
| { |
| llvm::raw_svector_ostream Out(FnName); |
| getCXXABI().getMangleContext().mangleDynamicInitializer(D, Out); |
| } |
| |
| // Create a variable initialization function. |
| llvm::Function *Fn = CreateGlobalInitOrCleanUpFunction( |
| FTy, FnName.str(), getTypes().arrangeNullaryFunction(), D->getLocation()); |
| |
| auto *ISA = D->getAttr<InitSegAttr>(); |
| CodeGenFunction(*this).GenerateCXXGlobalVarDeclInitFunc(Fn, D, Addr, |
| PerformInit); |
| |
| llvm::GlobalVariable *COMDATKey = |
| supportsCOMDAT() && D->isExternallyVisible() ? Addr : nullptr; |
| |
| if (D->getTLSKind()) { |
| // FIXME: Should we support init_priority for thread_local? |
| // FIXME: We only need to register one __cxa_thread_atexit function for the |
| // entire TU. |
| CXXThreadLocalInits.push_back(Fn); |
| CXXThreadLocalInitVars.push_back(D); |
| } else if (PerformInit && ISA) { |
| // Contract with backend that "init_seg(compiler)" corresponds to priority |
| // 200 and "init_seg(lib)" corresponds to priority 400. |
| int Priority = -1; |
| if (ISA->getSection() == ".CRT$XCC") |
| Priority = 200; |
| else if (ISA->getSection() == ".CRT$XCL") |
| Priority = 400; |
| |
| if (Priority != -1) |
| AddGlobalCtor(Fn, Priority, ~0U, COMDATKey); |
| else |
| EmitPointerToInitFunc(D, Addr, Fn, ISA); |
| } else if (auto *IPA = D->getAttr<InitPriorityAttr>()) { |
| OrderGlobalInitsOrStermFinalizers Key(IPA->getPriority(), |
| PrioritizedCXXGlobalInits.size()); |
| PrioritizedCXXGlobalInits.push_back(std::make_pair(Key, Fn)); |
| } else if (isTemplateInstantiation(D->getTemplateSpecializationKind()) || |
| getContext().GetGVALinkageForVariable(D) == GVA_DiscardableODR || |
| D->hasAttr<SelectAnyAttr>()) { |
| // C++ [basic.start.init]p2: |
| // Definitions of explicitly specialized class template static data |
| // members have ordered initialization. Other class template static data |
| // members (i.e., implicitly or explicitly instantiated specializations) |
| // have unordered initialization. |
| // |
| // As a consequence, we can put them into their own llvm.global_ctors entry. |
| // |
| // If the global is externally visible, put the initializer into a COMDAT |
| // group with the global being initialized. On most platforms, this is a |
| // minor startup time optimization. In the MS C++ ABI, there are no guard |
| // variables, so this COMDAT key is required for correctness. |
| // |
| // SelectAny globals will be comdat-folded. Put the initializer into a |
| // COMDAT group associated with the global, so the initializers get folded |
| // too. |
| I = DelayedCXXInitPosition.find(D); |
| // CXXGlobalInits.size() is the lex order number for the next deferred |
| // VarDecl. Use it when the current VarDecl is non-deferred. Although this |
| // lex order number is shared between current VarDecl and some following |
| // VarDecls, their order of insertion into `llvm.global_ctors` is the same |
| // as the lexing order and the following stable sort would preserve such |
| // order. |
| unsigned LexOrder = |
| I == DelayedCXXInitPosition.end() ? CXXGlobalInits.size() : I->second; |
| AddGlobalCtor(Fn, 65535, LexOrder, COMDATKey); |
| if (COMDATKey && (getTriple().isOSBinFormatELF() || |
| getTarget().getCXXABI().isMicrosoft())) { |
| // When COMDAT is used on ELF or in the MS C++ ABI, the key must be in |
| // llvm.used to prevent linker GC. |
| addUsedGlobal(COMDATKey); |
| } |
| |
| // If we used a COMDAT key for the global ctor, the init function can be |
| // discarded if the global ctor entry is discarded. |
| // FIXME: Do we need to restrict this to ELF and Wasm? |
| llvm::Comdat *C = Addr->getComdat(); |
| if (COMDATKey && C && |
| (getTarget().getTriple().isOSBinFormatELF() || |
| getTarget().getTriple().isOSBinFormatWasm())) { |
| Fn->setComdat(C); |
| } |
| } else { |
| I = DelayedCXXInitPosition.find(D); // Re-do lookup in case of re-hash. |
| if (I == DelayedCXXInitPosition.end()) { |
| CXXGlobalInits.push_back(Fn); |
| } else if (I->second != ~0U) { |
| assert(I->second < CXXGlobalInits.size() && |
| CXXGlobalInits[I->second] == nullptr); |
| CXXGlobalInits[I->second] = Fn; |
| } |
| } |
| |
| // Remember that we already emitted the initializer for this global. |
| DelayedCXXInitPosition[D] = ~0U; |
| } |
| |
| void CodeGenModule::EmitCXXThreadLocalInitFunc() { |
| getCXXABI().EmitThreadLocalInitFuncs( |
| *this, CXXThreadLocals, CXXThreadLocalInits, CXXThreadLocalInitVars); |
| |
| CXXThreadLocalInits.clear(); |
| CXXThreadLocalInitVars.clear(); |
| CXXThreadLocals.clear(); |
| } |
| |
| /* Build the initializer for a C++20 module: |
| This is arranged to be run only once regardless of how many times the module |
| might be included transitively. This arranged by using a guard variable. |
| |
| If there are no initializers at all (and also no imported modules) we reduce |
| this to an empty function (since the Itanium ABI requires that this function |
| be available to a caller, which might be produced by a different |
| implementation). |
| |
| First we call any initializers for imported modules. |
| We then call initializers for the Global Module Fragment (if present) |
| We then call initializers for the current module. |
| We then call initializers for the Private Module Fragment (if present) |
| */ |
| |
| void CodeGenModule::EmitCXXModuleInitFunc(Module *Primary) { |
| assert(Primary->isInterfaceOrPartition() && |
| "The function should only be called for C++20 named module interface" |
| " or partition."); |
| |
| while (!CXXGlobalInits.empty() && !CXXGlobalInits.back()) |
| CXXGlobalInits.pop_back(); |
| |
| // As noted above, we create the function, even if it is empty. |
| // Module initializers for imported modules are emitted first. |
| |
| // Collect all the modules that we import |
| llvm::SmallSetVector<Module *, 8> AllImports; |
| // Ones that we export |
| for (auto I : Primary->Exports) |
| AllImports.insert(I.getPointer()); |
| // Ones that we only import. |
| for (Module *M : Primary->Imports) |
| AllImports.insert(M); |
| // Ones that we import in the global module fragment or the private module |
| // fragment. |
| for (Module *SubM : Primary->submodules()) { |
| assert((SubM->isGlobalModule() || SubM->isPrivateModule()) && |
| "The sub modules of C++20 module unit should only be global module " |
| "fragments or private module framents."); |
| assert(SubM->Exports.empty() && |
| "The global mdoule fragments and the private module fragments are " |
| "not allowed to export import modules."); |
| for (Module *M : SubM->Imports) |
| AllImports.insert(M); |
| } |
| |
| SmallVector<llvm::Function *, 8> ModuleInits; |
| for (Module *M : AllImports) { |
| // No Itanium initializer in header like modules. |
| if (M->isHeaderLikeModule()) |
| continue; // TODO: warn of mixed use of module map modules and C++20? |
| // We're allowed to skip the initialization if we are sure it doesn't |
| // do any thing. |
| if (!M->isNamedModuleInterfaceHasInit()) |
| continue; |
| llvm::FunctionType *FTy = llvm::FunctionType::get(VoidTy, false); |
| SmallString<256> FnName; |
| { |
| llvm::raw_svector_ostream Out(FnName); |
| cast<ItaniumMangleContext>(getCXXABI().getMangleContext()) |
| .mangleModuleInitializer(M, Out); |
| } |
| assert(!GetGlobalValue(FnName.str()) && |
| "We should only have one use of the initializer call"); |
| llvm::Function *Fn = llvm::Function::Create( |
| FTy, llvm::Function::ExternalLinkage, FnName.str(), &getModule()); |
| ModuleInits.push_back(Fn); |
| } |
| |
| // Add any initializers with specified priority; this uses the same approach |
| // as EmitCXXGlobalInitFunc(). |
| if (!PrioritizedCXXGlobalInits.empty()) { |
| SmallVector<llvm::Function *, 8> LocalCXXGlobalInits; |
| llvm::array_pod_sort(PrioritizedCXXGlobalInits.begin(), |
| PrioritizedCXXGlobalInits.end()); |
| for (SmallVectorImpl<GlobalInitData>::iterator |
| I = PrioritizedCXXGlobalInits.begin(), |
| E = PrioritizedCXXGlobalInits.end(); |
| I != E;) { |
| SmallVectorImpl<GlobalInitData>::iterator PrioE = |
| std::upper_bound(I + 1, E, *I, GlobalInitPriorityCmp()); |
| |
| for (; I < PrioE; ++I) |
| ModuleInits.push_back(I->second); |
| } |
| } |
| |
| // Now append the ones without specified priority. |
| for (auto *F : CXXGlobalInits) |
| ModuleInits.push_back(F); |
| |
| llvm::FunctionType *FTy = llvm::FunctionType::get(VoidTy, false); |
| const CGFunctionInfo &FI = getTypes().arrangeNullaryFunction(); |
| |
| // We now build the initializer for this module, which has a mangled name |
| // as per the Itanium ABI . The action of the initializer is guarded so that |
| // each init is run just once (even though a module might be imported |
| // multiple times via nested use). |
| llvm::Function *Fn; |
| { |
| SmallString<256> InitFnName; |
| llvm::raw_svector_ostream Out(InitFnName); |
| cast<ItaniumMangleContext>(getCXXABI().getMangleContext()) |
| .mangleModuleInitializer(Primary, Out); |
| Fn = CreateGlobalInitOrCleanUpFunction( |
| FTy, llvm::Twine(InitFnName), FI, SourceLocation(), false, |
| llvm::GlobalVariable::ExternalLinkage); |
| |
| // If we have a completely empty initializer then we do not want to create |
| // the guard variable. |
| ConstantAddress GuardAddr = ConstantAddress::invalid(); |
| if (!ModuleInits.empty()) { |
| // Create the guard var. |
| llvm::GlobalVariable *Guard = new llvm::GlobalVariable( |
| getModule(), Int8Ty, /*isConstant=*/false, |
| llvm::GlobalVariable::InternalLinkage, |
| llvm::ConstantInt::get(Int8Ty, 0), InitFnName.str() + "__in_chrg"); |
| CharUnits GuardAlign = CharUnits::One(); |
| Guard->setAlignment(GuardAlign.getAsAlign()); |
| GuardAddr = ConstantAddress(Guard, Int8Ty, GuardAlign); |
| } |
| CodeGenFunction(*this).GenerateCXXGlobalInitFunc(Fn, ModuleInits, |
| GuardAddr); |
| } |
| |
| // We allow for the case that a module object is added to a linked binary |
| // without a specific call to the the initializer. This also ensures that |
| // implementation partition initializers are called when the partition |
| // is not imported as an interface. |
| AddGlobalCtor(Fn); |
| |
| // See the comment in EmitCXXGlobalInitFunc about OpenCL global init |
| // functions. |
| if (getLangOpts().OpenCL) { |
| GenKernelArgMetadata(Fn); |
| Fn->setCallingConv(llvm::CallingConv::SPIR_KERNEL); |
| } |
| |
| assert(!getLangOpts().CUDA || !getLangOpts().CUDAIsDevice || |
| getLangOpts().GPUAllowDeviceInit); |
| if (getLangOpts().HIP && getLangOpts().CUDAIsDevice) { |
| Fn->setCallingConv(llvm::CallingConv::AMDGPU_KERNEL); |
| Fn->addFnAttr("device-init"); |
| } |
| |
| // We are done with the inits. |
| AllImports.clear(); |
| PrioritizedCXXGlobalInits.clear(); |
| CXXGlobalInits.clear(); |
| ModuleInits.clear(); |
| } |
| |
| static SmallString<128> getTransformedFileName(llvm::Module &M) { |
| SmallString<128> FileName = llvm::sys::path::filename(M.getName()); |
| |
| if (FileName.empty()) |
| FileName = "<null>"; |
| |
| for (size_t i = 0; i < FileName.size(); ++i) { |
| // Replace everything that's not [a-zA-Z0-9._] with a _. This set happens |
| // to be the set of C preprocessing numbers. |
| if (!isPreprocessingNumberBody(FileName[i])) |
| FileName[i] = '_'; |
| } |
| |
| return FileName; |
| } |
| |
| static std::string getPrioritySuffix(unsigned int Priority) { |
| assert(Priority <= 65535 && "Priority should always be <= 65535."); |
| |
| // Compute the function suffix from priority. Prepend with zeroes to make |
| // sure the function names are also ordered as priorities. |
| std::string PrioritySuffix = llvm::utostr(Priority); |
| PrioritySuffix = std::string(6 - PrioritySuffix.size(), '0') + PrioritySuffix; |
| |
| return PrioritySuffix; |
| } |
| |
| void |
| CodeGenModule::EmitCXXGlobalInitFunc() { |
| while (!CXXGlobalInits.empty() && !CXXGlobalInits.back()) |
| CXXGlobalInits.pop_back(); |
| |
| // When we import C++20 modules, we must run their initializers first. |
| SmallVector<llvm::Function *, 8> ModuleInits; |
| if (CXX20ModuleInits) |
| for (Module *M : ImportedModules) { |
| // No Itanium initializer in header like modules. |
| if (M->isHeaderLikeModule()) |
| continue; |
| llvm::FunctionType *FTy = llvm::FunctionType::get(VoidTy, false); |
| SmallString<256> FnName; |
| { |
| llvm::raw_svector_ostream Out(FnName); |
| cast<ItaniumMangleContext>(getCXXABI().getMangleContext()) |
| .mangleModuleInitializer(M, Out); |
| } |
| assert(!GetGlobalValue(FnName.str()) && |
| "We should only have one use of the initializer call"); |
| llvm::Function *Fn = llvm::Function::Create( |
| FTy, llvm::Function::ExternalLinkage, FnName.str(), &getModule()); |
| ModuleInits.push_back(Fn); |
| } |
| |
| if (ModuleInits.empty() && CXXGlobalInits.empty() && |
| PrioritizedCXXGlobalInits.empty()) |
| return; |
| |
| llvm::FunctionType *FTy = llvm::FunctionType::get(VoidTy, false); |
| const CGFunctionInfo &FI = getTypes().arrangeNullaryFunction(); |
| |
| // Create our global prioritized initialization function. |
| if (!PrioritizedCXXGlobalInits.empty()) { |
| SmallVector<llvm::Function *, 8> LocalCXXGlobalInits; |
| llvm::array_pod_sort(PrioritizedCXXGlobalInits.begin(), |
| PrioritizedCXXGlobalInits.end()); |
| // Iterate over "chunks" of ctors with same priority and emit each chunk |
| // into separate function. Note - everything is sorted first by priority, |
| // second - by lex order, so we emit ctor functions in proper order. |
| for (SmallVectorImpl<GlobalInitData >::iterator |
| I = PrioritizedCXXGlobalInits.begin(), |
| E = PrioritizedCXXGlobalInits.end(); I != E; ) { |
| SmallVectorImpl<GlobalInitData >::iterator |
| PrioE = std::upper_bound(I + 1, E, *I, GlobalInitPriorityCmp()); |
| |
| LocalCXXGlobalInits.clear(); |
| |
| unsigned int Priority = I->first.priority; |
| llvm::Function *Fn = CreateGlobalInitOrCleanUpFunction( |
| FTy, "_GLOBAL__I_" + getPrioritySuffix(Priority), FI); |
| |
| // Prepend the module inits to the highest priority set. |
| if (!ModuleInits.empty()) { |
| for (auto *F : ModuleInits) |
| LocalCXXGlobalInits.push_back(F); |
| ModuleInits.clear(); |
| } |
| |
| for (; I < PrioE; ++I) |
| LocalCXXGlobalInits.push_back(I->second); |
| |
| CodeGenFunction(*this).GenerateCXXGlobalInitFunc(Fn, LocalCXXGlobalInits); |
| AddGlobalCtor(Fn, Priority); |
| } |
| PrioritizedCXXGlobalInits.clear(); |
| } |
| |
| if (getCXXABI().useSinitAndSterm() && ModuleInits.empty() && |
| CXXGlobalInits.empty()) |
| return; |
| |
| for (auto *F : CXXGlobalInits) |
| ModuleInits.push_back(F); |
| CXXGlobalInits.clear(); |
| |
| // Include the filename in the symbol name. Including "sub_" matches gcc |
| // and makes sure these symbols appear lexicographically behind the symbols |
| // with priority emitted above. Module implementation units behave the same |
| // way as a non-modular TU with imports. |
| llvm::Function *Fn; |
| if (CXX20ModuleInits && getContext().getCurrentNamedModule() && |
| !getContext().getCurrentNamedModule()->isModuleImplementation()) { |
| SmallString<256> InitFnName; |
| llvm::raw_svector_ostream Out(InitFnName); |
| cast<ItaniumMangleContext>(getCXXABI().getMangleContext()) |
| .mangleModuleInitializer(getContext().getCurrentNamedModule(), Out); |
| Fn = CreateGlobalInitOrCleanUpFunction( |
| FTy, llvm::Twine(InitFnName), FI, SourceLocation(), false, |
| llvm::GlobalVariable::ExternalLinkage); |
| } else |
| Fn = CreateGlobalInitOrCleanUpFunction( |
| FTy, |
| llvm::Twine("_GLOBAL__sub_I_", getTransformedFileName(getModule())), |
| FI); |
| |
| CodeGenFunction(*this).GenerateCXXGlobalInitFunc(Fn, ModuleInits); |
| AddGlobalCtor(Fn); |
| |
| // In OpenCL global init functions must be converted to kernels in order to |
| // be able to launch them from the host. |
| // FIXME: Some more work might be needed to handle destructors correctly. |
| // Current initialization function makes use of function pointers callbacks. |
| // We can't support function pointers especially between host and device. |
| // However it seems global destruction has little meaning without any |
| // dynamic resource allocation on the device and program scope variables are |
| // destroyed by the runtime when program is released. |
| if (getLangOpts().OpenCL) { |
| GenKernelArgMetadata(Fn); |
| Fn->setCallingConv(llvm::CallingConv::SPIR_KERNEL); |
| } |
| |
| assert(!getLangOpts().CUDA || !getLangOpts().CUDAIsDevice || |
| getLangOpts().GPUAllowDeviceInit); |
| if (getLangOpts().HIP && getLangOpts().CUDAIsDevice) { |
| Fn->setCallingConv(llvm::CallingConv::AMDGPU_KERNEL); |
| Fn->addFnAttr("device-init"); |
| } |
| |
| ModuleInits.clear(); |
| } |
| |
| void CodeGenModule::EmitCXXGlobalCleanUpFunc() { |
| if (CXXGlobalDtorsOrStermFinalizers.empty() && |
| PrioritizedCXXStermFinalizers.empty()) |
| return; |
| |
| llvm::FunctionType *FTy = llvm::FunctionType::get(VoidTy, false); |
| const CGFunctionInfo &FI = getTypes().arrangeNullaryFunction(); |
| |
| // Create our global prioritized cleanup function. |
| if (!PrioritizedCXXStermFinalizers.empty()) { |
| SmallVector<CXXGlobalDtorsOrStermFinalizer_t, 8> LocalCXXStermFinalizers; |
| llvm::array_pod_sort(PrioritizedCXXStermFinalizers.begin(), |
| PrioritizedCXXStermFinalizers.end()); |
| // Iterate over "chunks" of dtors with same priority and emit each chunk |
| // into separate function. Note - everything is sorted first by priority, |
| // second - by lex order, so we emit dtor functions in proper order. |
| for (SmallVectorImpl<StermFinalizerData>::iterator |
| I = PrioritizedCXXStermFinalizers.begin(), |
| E = PrioritizedCXXStermFinalizers.end(); |
| I != E;) { |
| SmallVectorImpl<StermFinalizerData>::iterator PrioE = |
| std::upper_bound(I + 1, E, *I, StermFinalizerPriorityCmp()); |
| |
| LocalCXXStermFinalizers.clear(); |
| |
| unsigned int Priority = I->first.priority; |
| llvm::Function *Fn = CreateGlobalInitOrCleanUpFunction( |
| FTy, "_GLOBAL__a_" + getPrioritySuffix(Priority), FI); |
| |
| for (; I < PrioE; ++I) { |
| llvm::FunctionCallee DtorFn = I->second; |
| LocalCXXStermFinalizers.emplace_back(DtorFn.getFunctionType(), |
| DtorFn.getCallee(), nullptr); |
| } |
| |
| CodeGenFunction(*this).GenerateCXXGlobalCleanUpFunc( |
| Fn, LocalCXXStermFinalizers); |
| AddGlobalDtor(Fn, Priority); |
| } |
| PrioritizedCXXStermFinalizers.clear(); |
| } |
| |
| if (CXXGlobalDtorsOrStermFinalizers.empty()) |
| return; |
| |
| // Create our global cleanup function. |
| llvm::Function *Fn = |
| CreateGlobalInitOrCleanUpFunction(FTy, "_GLOBAL__D_a", FI); |
| |
| CodeGenFunction(*this).GenerateCXXGlobalCleanUpFunc( |
| Fn, CXXGlobalDtorsOrStermFinalizers); |
| AddGlobalDtor(Fn); |
| CXXGlobalDtorsOrStermFinalizers.clear(); |
| } |
| |
| /// Emit the code necessary to initialize the given global variable. |
| void CodeGenFunction::GenerateCXXGlobalVarDeclInitFunc(llvm::Function *Fn, |
| const VarDecl *D, |
| llvm::GlobalVariable *Addr, |
| bool PerformInit) { |
| // Check if we need to emit debug info for variable initializer. |
| if (D->hasAttr<NoDebugAttr>()) |
| DebugInfo = nullptr; // disable debug info indefinitely for this function |
| |
| CurEHLocation = D->getBeginLoc(); |
| |
| StartFunction(GlobalDecl(D, DynamicInitKind::Initializer), |
| getContext().VoidTy, Fn, getTypes().arrangeNullaryFunction(), |
| FunctionArgList()); |
| // Emit an artificial location for this function. |
| auto AL = ApplyDebugLocation::CreateArtificial(*this); |
| |
| // Use guarded initialization if the global variable is weak. This |
| // occurs for, e.g., instantiated static data members and |
| // definitions explicitly marked weak. |
| // |
| // Also use guarded initialization for a variable with dynamic TLS and |
| // unordered initialization. (If the initialization is ordered, the ABI |
| // layer will guard the whole-TU initialization for us.) |
| if (Addr->hasWeakLinkage() || Addr->hasLinkOnceLinkage() || |
| (D->getTLSKind() == VarDecl::TLS_Dynamic && |
| isTemplateInstantiation(D->getTemplateSpecializationKind()))) { |
| EmitCXXGuardedInit(*D, Addr, PerformInit); |
| } else { |
| EmitCXXGlobalVarDeclInit(*D, Addr, PerformInit); |
| } |
| |
| if (getLangOpts().HLSL) |
| CGM.getHLSLRuntime().annotateHLSLResource(D, Addr); |
| |
| FinishFunction(); |
| } |
| |
| void |
| CodeGenFunction::GenerateCXXGlobalInitFunc(llvm::Function *Fn, |
| ArrayRef<llvm::Function *> Decls, |
| ConstantAddress Guard) { |
| { |
| auto NL = ApplyDebugLocation::CreateEmpty(*this); |
| StartFunction(GlobalDecl(), getContext().VoidTy, Fn, |
| getTypes().arrangeNullaryFunction(), FunctionArgList()); |
| // Emit an artificial location for this function. |
| auto AL = ApplyDebugLocation::CreateArtificial(*this); |
| |
| llvm::BasicBlock *ExitBlock = nullptr; |
| if (Guard.isValid()) { |
| // If we have a guard variable, check whether we've already performed |
| // these initializations. This happens for TLS initialization functions. |
| llvm::Value *GuardVal = Builder.CreateLoad(Guard); |
| llvm::Value *Uninit = Builder.CreateIsNull(GuardVal, |
| "guard.uninitialized"); |
| llvm::BasicBlock *InitBlock = createBasicBlock("init"); |
| ExitBlock = createBasicBlock("exit"); |
| EmitCXXGuardedInitBranch(Uninit, InitBlock, ExitBlock, |
| GuardKind::TlsGuard, nullptr); |
| EmitBlock(InitBlock); |
| // Mark as initialized before initializing anything else. If the |
| // initializers use previously-initialized thread_local vars, that's |
| // probably supposed to be OK, but the standard doesn't say. |
| Builder.CreateStore(llvm::ConstantInt::get(GuardVal->getType(),1), Guard); |
| |
| // The guard variable can't ever change again. |
| EmitInvariantStart( |
| Guard.getPointer(), |
| CharUnits::fromQuantity( |
| CGM.getDataLayout().getTypeAllocSize(GuardVal->getType()))); |
| } |
| |
| RunCleanupsScope Scope(*this); |
| |
| // When building in Objective-C++ ARC mode, create an autorelease pool |
| // around the global initializers. |
| if (getLangOpts().ObjCAutoRefCount && getLangOpts().CPlusPlus) { |
| llvm::Value *token = EmitObjCAutoreleasePoolPush(); |
| EmitObjCAutoreleasePoolCleanup(token); |
| } |
| |
| for (unsigned i = 0, e = Decls.size(); i != e; ++i) |
| if (Decls[i]) |
| EmitRuntimeCall(Decls[i]); |
| |
| Scope.ForceCleanup(); |
| |
| if (ExitBlock) { |
| Builder.CreateBr(ExitBlock); |
| EmitBlock(ExitBlock); |
| } |
| } |
| |
| FinishFunction(); |
| } |
| |
| void CodeGenFunction::GenerateCXXGlobalCleanUpFunc( |
| llvm::Function *Fn, |
| ArrayRef<std::tuple<llvm::FunctionType *, llvm::WeakTrackingVH, |
| llvm::Constant *>> |
| DtorsOrStermFinalizers) { |
| { |
| auto NL = ApplyDebugLocation::CreateEmpty(*this); |
| StartFunction(GlobalDecl(), getContext().VoidTy, Fn, |
| getTypes().arrangeNullaryFunction(), FunctionArgList()); |
| // Emit an artificial location for this function. |
| auto AL = ApplyDebugLocation::CreateArtificial(*this); |
| |
| // Emit the cleanups, in reverse order from construction. |
| for (unsigned i = 0, e = DtorsOrStermFinalizers.size(); i != e; ++i) { |
| llvm::FunctionType *CalleeTy; |
| llvm::Value *Callee; |
| llvm::Constant *Arg; |
| std::tie(CalleeTy, Callee, Arg) = DtorsOrStermFinalizers[e - i - 1]; |
| |
| llvm::CallInst *CI = nullptr; |
| if (Arg == nullptr) { |
| assert( |
| CGM.getCXXABI().useSinitAndSterm() && |
| "Arg could not be nullptr unless using sinit and sterm functions."); |
| CI = Builder.CreateCall(CalleeTy, Callee); |
| } else |
| CI = Builder.CreateCall(CalleeTy, Callee, Arg); |
| |
| // Make sure the call and the callee agree on calling convention. |
| if (llvm::Function *F = dyn_cast<llvm::Function>(Callee)) |
| CI->setCallingConv(F->getCallingConv()); |
| } |
| } |
| |
| FinishFunction(); |
| } |
| |
| /// generateDestroyHelper - Generates a helper function which, when |
| /// invoked, destroys the given object. The address of the object |
| /// should be in global memory. |
| llvm::Function *CodeGenFunction::generateDestroyHelper( |
| Address addr, QualType type, Destroyer *destroyer, |
| bool useEHCleanupForArray, const VarDecl *VD) { |
| FunctionArgList args; |
| ImplicitParamDecl Dst(getContext(), getContext().VoidPtrTy, |
| ImplicitParamKind::Other); |
| args.push_back(&Dst); |
| |
| const CGFunctionInfo &FI = |
| CGM.getTypes().arrangeBuiltinFunctionDeclaration(getContext().VoidTy, args); |
| llvm::FunctionType *FTy = CGM.getTypes().GetFunctionType(FI); |
| llvm::Function *fn = CGM.CreateGlobalInitOrCleanUpFunction( |
| FTy, "__cxx_global_array_dtor", FI, VD->getLocation()); |
| |
| CurEHLocation = VD->getBeginLoc(); |
| |
| StartFunction(GlobalDecl(VD, DynamicInitKind::GlobalArrayDestructor), |
| getContext().VoidTy, fn, FI, args); |
| // Emit an artificial location for this function. |
| auto AL = ApplyDebugLocation::CreateArtificial(*this); |
| |
| emitDestroy(addr, type, destroyer, useEHCleanupForArray); |
| |
| FinishFunction(); |
| |
| return fn; |
| } |
