forked from OSchip/llvm-project
1931 lines
72 KiB
C++
1931 lines
72 KiB
C++
//===--- CGDecl.cpp - Emit LLVM Code for declarations ---------------------===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// This contains code to emit Decl nodes as LLVM code.
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//
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//===----------------------------------------------------------------------===//
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#include "CGBlocks.h"
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#include "CGCXXABI.h"
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#include "CGCleanup.h"
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#include "CGDebugInfo.h"
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#include "CGOpenCLRuntime.h"
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#include "CGOpenMPRuntime.h"
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#include "CodeGenFunction.h"
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#include "CodeGenModule.h"
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#include "ConstantEmitter.h"
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#include "TargetInfo.h"
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#include "clang/AST/ASTContext.h"
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#include "clang/AST/CharUnits.h"
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#include "clang/AST/Decl.h"
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#include "clang/AST/DeclObjC.h"
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#include "clang/AST/DeclOpenMP.h"
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#include "clang/Basic/SourceManager.h"
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#include "clang/Basic/TargetInfo.h"
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#include "clang/CodeGen/CGFunctionInfo.h"
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#include "clang/Frontend/CodeGenOptions.h"
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#include "llvm/IR/DataLayout.h"
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#include "llvm/IR/GlobalVariable.h"
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#include "llvm/IR/Intrinsics.h"
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#include "llvm/IR/Type.h"
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using namespace clang;
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using namespace CodeGen;
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void CodeGenFunction::EmitDecl(const Decl &D) {
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switch (D.getKind()) {
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case Decl::BuiltinTemplate:
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case Decl::TranslationUnit:
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case Decl::ExternCContext:
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case Decl::Namespace:
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case Decl::UnresolvedUsingTypename:
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case Decl::ClassTemplateSpecialization:
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case Decl::ClassTemplatePartialSpecialization:
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case Decl::VarTemplateSpecialization:
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case Decl::VarTemplatePartialSpecialization:
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case Decl::TemplateTypeParm:
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case Decl::UnresolvedUsingValue:
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case Decl::NonTypeTemplateParm:
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case Decl::CXXDeductionGuide:
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case Decl::CXXMethod:
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case Decl::CXXConstructor:
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case Decl::CXXDestructor:
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case Decl::CXXConversion:
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case Decl::Field:
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case Decl::MSProperty:
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case Decl::IndirectField:
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case Decl::ObjCIvar:
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case Decl::ObjCAtDefsField:
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case Decl::ParmVar:
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case Decl::ImplicitParam:
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case Decl::ClassTemplate:
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case Decl::VarTemplate:
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case Decl::FunctionTemplate:
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case Decl::TypeAliasTemplate:
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case Decl::TemplateTemplateParm:
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case Decl::ObjCMethod:
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case Decl::ObjCCategory:
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case Decl::ObjCProtocol:
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case Decl::ObjCInterface:
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case Decl::ObjCCategoryImpl:
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case Decl::ObjCImplementation:
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case Decl::ObjCProperty:
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case Decl::ObjCCompatibleAlias:
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case Decl::PragmaComment:
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case Decl::PragmaDetectMismatch:
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case Decl::AccessSpec:
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case Decl::LinkageSpec:
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case Decl::Export:
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case Decl::ObjCPropertyImpl:
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case Decl::FileScopeAsm:
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case Decl::Friend:
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case Decl::FriendTemplate:
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case Decl::Block:
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case Decl::Captured:
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case Decl::ClassScopeFunctionSpecialization:
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case Decl::UsingShadow:
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case Decl::ConstructorUsingShadow:
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case Decl::ObjCTypeParam:
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case Decl::Binding:
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llvm_unreachable("Declaration should not be in declstmts!");
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case Decl::Function: // void X();
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case Decl::Record: // struct/union/class X;
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case Decl::Enum: // enum X;
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case Decl::EnumConstant: // enum ? { X = ? }
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case Decl::CXXRecord: // struct/union/class X; [C++]
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case Decl::StaticAssert: // static_assert(X, ""); [C++0x]
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case Decl::Label: // __label__ x;
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case Decl::Import:
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case Decl::OMPThreadPrivate:
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case Decl::OMPCapturedExpr:
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case Decl::Empty:
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// None of these decls require codegen support.
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return;
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case Decl::NamespaceAlias:
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if (CGDebugInfo *DI = getDebugInfo())
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DI->EmitNamespaceAlias(cast<NamespaceAliasDecl>(D));
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return;
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case Decl::Using: // using X; [C++]
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if (CGDebugInfo *DI = getDebugInfo())
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DI->EmitUsingDecl(cast<UsingDecl>(D));
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return;
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case Decl::UsingPack:
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for (auto *Using : cast<UsingPackDecl>(D).expansions())
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EmitDecl(*Using);
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return;
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case Decl::UsingDirective: // using namespace X; [C++]
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if (CGDebugInfo *DI = getDebugInfo())
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DI->EmitUsingDirective(cast<UsingDirectiveDecl>(D));
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return;
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case Decl::Var:
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case Decl::Decomposition: {
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const VarDecl &VD = cast<VarDecl>(D);
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assert(VD.isLocalVarDecl() &&
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"Should not see file-scope variables inside a function!");
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EmitVarDecl(VD);
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if (auto *DD = dyn_cast<DecompositionDecl>(&VD))
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for (auto *B : DD->bindings())
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if (auto *HD = B->getHoldingVar())
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EmitVarDecl(*HD);
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return;
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}
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case Decl::OMPDeclareReduction:
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return CGM.EmitOMPDeclareReduction(cast<OMPDeclareReductionDecl>(&D), this);
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case Decl::Typedef: // typedef int X;
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case Decl::TypeAlias: { // using X = int; [C++0x]
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const TypedefNameDecl &TD = cast<TypedefNameDecl>(D);
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QualType Ty = TD.getUnderlyingType();
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if (Ty->isVariablyModifiedType())
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EmitVariablyModifiedType(Ty);
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}
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}
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}
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/// EmitVarDecl - This method handles emission of any variable declaration
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/// inside a function, including static vars etc.
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void CodeGenFunction::EmitVarDecl(const VarDecl &D) {
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if (D.hasExternalStorage())
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// Don't emit it now, allow it to be emitted lazily on its first use.
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return;
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// Some function-scope variable does not have static storage but still
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// needs to be emitted like a static variable, e.g. a function-scope
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// variable in constant address space in OpenCL.
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if (D.getStorageDuration() != SD_Automatic) {
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// Static sampler variables translated to function calls.
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if (D.getType()->isSamplerT())
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return;
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llvm::GlobalValue::LinkageTypes Linkage =
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CGM.getLLVMLinkageVarDefinition(&D, /*isConstant=*/false);
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// FIXME: We need to force the emission/use of a guard variable for
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// some variables even if we can constant-evaluate them because
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// we can't guarantee every translation unit will constant-evaluate them.
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return EmitStaticVarDecl(D, Linkage);
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}
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if (D.getType().getAddressSpace() == LangAS::opencl_local)
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return CGM.getOpenCLRuntime().EmitWorkGroupLocalVarDecl(*this, D);
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assert(D.hasLocalStorage());
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return EmitAutoVarDecl(D);
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}
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static std::string getStaticDeclName(CodeGenModule &CGM, const VarDecl &D) {
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if (CGM.getLangOpts().CPlusPlus)
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return CGM.getMangledName(&D).str();
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// If this isn't C++, we don't need a mangled name, just a pretty one.
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assert(!D.isExternallyVisible() && "name shouldn't matter");
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std::string ContextName;
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const DeclContext *DC = D.getDeclContext();
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if (auto *CD = dyn_cast<CapturedDecl>(DC))
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DC = cast<DeclContext>(CD->getNonClosureContext());
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if (const auto *FD = dyn_cast<FunctionDecl>(DC))
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ContextName = CGM.getMangledName(FD);
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else if (const auto *BD = dyn_cast<BlockDecl>(DC))
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ContextName = CGM.getBlockMangledName(GlobalDecl(), BD);
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else if (const auto *OMD = dyn_cast<ObjCMethodDecl>(DC))
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ContextName = OMD->getSelector().getAsString();
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else
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llvm_unreachable("Unknown context for static var decl");
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ContextName += "." + D.getNameAsString();
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return ContextName;
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}
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llvm::Constant *CodeGenModule::getOrCreateStaticVarDecl(
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const VarDecl &D, llvm::GlobalValue::LinkageTypes Linkage) {
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// In general, we don't always emit static var decls once before we reference
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// them. It is possible to reference them before emitting the function that
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// contains them, and it is possible to emit the containing function multiple
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// times.
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if (llvm::Constant *ExistingGV = StaticLocalDeclMap[&D])
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return ExistingGV;
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QualType Ty = D.getType();
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assert(Ty->isConstantSizeType() && "VLAs can't be static");
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// Use the label if the variable is renamed with the asm-label extension.
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std::string Name;
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if (D.hasAttr<AsmLabelAttr>())
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Name = getMangledName(&D);
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else
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Name = getStaticDeclName(*this, D);
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llvm::Type *LTy = getTypes().ConvertTypeForMem(Ty);
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LangAS AS = GetGlobalVarAddressSpace(&D);
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unsigned TargetAS = getContext().getTargetAddressSpace(AS);
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// Local address space cannot have an initializer.
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llvm::Constant *Init = nullptr;
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if (Ty.getAddressSpace() != LangAS::opencl_local)
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Init = EmitNullConstant(Ty);
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else
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Init = llvm::UndefValue::get(LTy);
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llvm::GlobalVariable *GV = new llvm::GlobalVariable(
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getModule(), LTy, Ty.isConstant(getContext()), Linkage, Init, Name,
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nullptr, llvm::GlobalVariable::NotThreadLocal, TargetAS);
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GV->setAlignment(getContext().getDeclAlign(&D).getQuantity());
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setGlobalVisibility(GV, &D);
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if (supportsCOMDAT() && GV->isWeakForLinker())
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GV->setComdat(TheModule.getOrInsertComdat(GV->getName()));
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if (D.getTLSKind())
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setTLSMode(GV, D);
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if (D.isExternallyVisible()) {
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if (D.hasAttr<DLLImportAttr>())
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GV->setDLLStorageClass(llvm::GlobalVariable::DLLImportStorageClass);
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else if (D.hasAttr<DLLExportAttr>())
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GV->setDLLStorageClass(llvm::GlobalVariable::DLLExportStorageClass);
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}
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// Make sure the result is of the correct type.
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LangAS ExpectedAS = Ty.getAddressSpace();
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llvm::Constant *Addr = GV;
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if (AS != ExpectedAS) {
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Addr = getTargetCodeGenInfo().performAddrSpaceCast(
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*this, GV, AS, ExpectedAS,
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LTy->getPointerTo(getContext().getTargetAddressSpace(ExpectedAS)));
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}
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setStaticLocalDeclAddress(&D, Addr);
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// Ensure that the static local gets initialized by making sure the parent
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// function gets emitted eventually.
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const Decl *DC = cast<Decl>(D.getDeclContext());
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// We can't name blocks or captured statements directly, so try to emit their
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// parents.
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if (isa<BlockDecl>(DC) || isa<CapturedDecl>(DC)) {
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DC = DC->getNonClosureContext();
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// FIXME: Ensure that global blocks get emitted.
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if (!DC)
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return Addr;
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}
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GlobalDecl GD;
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if (const auto *CD = dyn_cast<CXXConstructorDecl>(DC))
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GD = GlobalDecl(CD, Ctor_Base);
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else if (const auto *DD = dyn_cast<CXXDestructorDecl>(DC))
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GD = GlobalDecl(DD, Dtor_Base);
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else if (const auto *FD = dyn_cast<FunctionDecl>(DC))
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GD = GlobalDecl(FD);
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else {
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// Don't do anything for Obj-C method decls or global closures. We should
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// never defer them.
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assert(isa<ObjCMethodDecl>(DC) && "unexpected parent code decl");
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}
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if (GD.getDecl())
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(void)GetAddrOfGlobal(GD);
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return Addr;
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}
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/// hasNontrivialDestruction - Determine whether a type's destruction is
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/// non-trivial. If so, and the variable uses static initialization, we must
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/// register its destructor to run on exit.
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static bool hasNontrivialDestruction(QualType T) {
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CXXRecordDecl *RD = T->getBaseElementTypeUnsafe()->getAsCXXRecordDecl();
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return RD && !RD->hasTrivialDestructor();
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}
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/// AddInitializerToStaticVarDecl - Add the initializer for 'D' to the
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/// global variable that has already been created for it. If the initializer
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/// has a different type than GV does, this may free GV and return a different
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/// one. Otherwise it just returns GV.
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llvm::GlobalVariable *
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CodeGenFunction::AddInitializerToStaticVarDecl(const VarDecl &D,
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llvm::GlobalVariable *GV) {
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ConstantEmitter emitter(*this);
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llvm::Constant *Init = emitter.tryEmitForInitializer(D);
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// If constant emission failed, then this should be a C++ static
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// initializer.
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if (!Init) {
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if (!getLangOpts().CPlusPlus)
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CGM.ErrorUnsupported(D.getInit(), "constant l-value expression");
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else if (HaveInsertPoint()) {
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// Since we have a static initializer, this global variable can't
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// be constant.
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GV->setConstant(false);
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EmitCXXGuardedInit(D, GV, /*PerformInit*/true);
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}
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return GV;
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}
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// The initializer may differ in type from the global. Rewrite
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// the global to match the initializer. (We have to do this
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// because some types, like unions, can't be completely represented
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// in the LLVM type system.)
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if (GV->getType()->getElementType() != Init->getType()) {
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llvm::GlobalVariable *OldGV = GV;
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GV = new llvm::GlobalVariable(CGM.getModule(), Init->getType(),
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OldGV->isConstant(),
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OldGV->getLinkage(), Init, "",
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/*InsertBefore*/ OldGV,
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OldGV->getThreadLocalMode(),
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CGM.getContext().getTargetAddressSpace(D.getType()));
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GV->setVisibility(OldGV->getVisibility());
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GV->setComdat(OldGV->getComdat());
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// Steal the name of the old global
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GV->takeName(OldGV);
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// Replace all uses of the old global with the new global
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llvm::Constant *NewPtrForOldDecl =
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llvm::ConstantExpr::getBitCast(GV, OldGV->getType());
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OldGV->replaceAllUsesWith(NewPtrForOldDecl);
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// Erase the old global, since it is no longer used.
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OldGV->eraseFromParent();
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}
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GV->setConstant(CGM.isTypeConstant(D.getType(), true));
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GV->setInitializer(Init);
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emitter.finalize(GV);
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if (hasNontrivialDestruction(D.getType()) && HaveInsertPoint()) {
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// We have a constant initializer, but a nontrivial destructor. We still
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// need to perform a guarded "initialization" in order to register the
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// destructor.
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EmitCXXGuardedInit(D, GV, /*PerformInit*/false);
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}
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return GV;
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}
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void CodeGenFunction::EmitStaticVarDecl(const VarDecl &D,
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llvm::GlobalValue::LinkageTypes Linkage) {
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// Check to see if we already have a global variable for this
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// declaration. This can happen when double-emitting function
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// bodies, e.g. with complete and base constructors.
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llvm::Constant *addr = CGM.getOrCreateStaticVarDecl(D, Linkage);
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CharUnits alignment = getContext().getDeclAlign(&D);
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// Store into LocalDeclMap before generating initializer to handle
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// circular references.
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setAddrOfLocalVar(&D, Address(addr, alignment));
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// We can't have a VLA here, but we can have a pointer to a VLA,
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// even though that doesn't really make any sense.
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// Make sure to evaluate VLA bounds now so that we have them for later.
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if (D.getType()->isVariablyModifiedType())
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EmitVariablyModifiedType(D.getType());
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// Save the type in case adding the initializer forces a type change.
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llvm::Type *expectedType = addr->getType();
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llvm::GlobalVariable *var =
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cast<llvm::GlobalVariable>(addr->stripPointerCasts());
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// CUDA's local and local static __shared__ variables should not
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// have any non-empty initializers. This is ensured by Sema.
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// Whatever initializer such variable may have when it gets here is
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// a no-op and should not be emitted.
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bool isCudaSharedVar = getLangOpts().CUDA && getLangOpts().CUDAIsDevice &&
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D.hasAttr<CUDASharedAttr>();
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// If this value has an initializer, emit it.
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if (D.getInit() && !isCudaSharedVar)
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var = AddInitializerToStaticVarDecl(D, var);
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var->setAlignment(alignment.getQuantity());
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if (D.hasAttr<AnnotateAttr>())
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CGM.AddGlobalAnnotations(&D, var);
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if (auto *SA = D.getAttr<PragmaClangBSSSectionAttr>())
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var->addAttribute("bss-section", SA->getName());
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if (auto *SA = D.getAttr<PragmaClangDataSectionAttr>())
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var->addAttribute("data-section", SA->getName());
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if (auto *SA = D.getAttr<PragmaClangRodataSectionAttr>())
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var->addAttribute("rodata-section", SA->getName());
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if (const SectionAttr *SA = D.getAttr<SectionAttr>())
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var->setSection(SA->getName());
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if (D.hasAttr<UsedAttr>())
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CGM.addUsedGlobal(var);
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// We may have to cast the constant because of the initializer
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// mismatch above.
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//
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// FIXME: It is really dangerous to store this in the map; if anyone
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// RAUW's the GV uses of this constant will be invalid.
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llvm::Constant *castedAddr =
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llvm::ConstantExpr::getPointerBitCastOrAddrSpaceCast(var, expectedType);
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if (var != castedAddr)
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LocalDeclMap.find(&D)->second = Address(castedAddr, alignment);
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CGM.setStaticLocalDeclAddress(&D, castedAddr);
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CGM.getSanitizerMetadata()->reportGlobalToASan(var, D);
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// Emit global variable debug descriptor for static vars.
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CGDebugInfo *DI = getDebugInfo();
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if (DI &&
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CGM.getCodeGenOpts().getDebugInfo() >= codegenoptions::LimitedDebugInfo) {
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DI->setLocation(D.getLocation());
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DI->EmitGlobalVariable(var, &D);
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}
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}
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namespace {
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struct DestroyObject final : EHScopeStack::Cleanup {
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DestroyObject(Address addr, QualType type,
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CodeGenFunction::Destroyer *destroyer,
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bool useEHCleanupForArray)
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: addr(addr), type(type), destroyer(destroyer),
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useEHCleanupForArray(useEHCleanupForArray) {}
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Address addr;
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QualType type;
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CodeGenFunction::Destroyer *destroyer;
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bool useEHCleanupForArray;
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void Emit(CodeGenFunction &CGF, Flags flags) override {
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// Don't use an EH cleanup recursively from an EH cleanup.
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bool useEHCleanupForArray =
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flags.isForNormalCleanup() && this->useEHCleanupForArray;
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CGF.emitDestroy(addr, type, destroyer, useEHCleanupForArray);
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}
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};
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struct DestroyNRVOVariable final : EHScopeStack::Cleanup {
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DestroyNRVOVariable(Address addr,
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const CXXDestructorDecl *Dtor,
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llvm::Value *NRVOFlag)
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: Dtor(Dtor), NRVOFlag(NRVOFlag), Loc(addr) {}
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const CXXDestructorDecl *Dtor;
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llvm::Value *NRVOFlag;
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Address Loc;
|
|
|
|
void Emit(CodeGenFunction &CGF, Flags flags) override {
|
|
// Along the exceptions path we always execute the dtor.
|
|
bool NRVO = flags.isForNormalCleanup() && NRVOFlag;
|
|
|
|
llvm::BasicBlock *SkipDtorBB = nullptr;
|
|
if (NRVO) {
|
|
// If we exited via NRVO, we skip the destructor call.
|
|
llvm::BasicBlock *RunDtorBB = CGF.createBasicBlock("nrvo.unused");
|
|
SkipDtorBB = CGF.createBasicBlock("nrvo.skipdtor");
|
|
llvm::Value *DidNRVO =
|
|
CGF.Builder.CreateFlagLoad(NRVOFlag, "nrvo.val");
|
|
CGF.Builder.CreateCondBr(DidNRVO, SkipDtorBB, RunDtorBB);
|
|
CGF.EmitBlock(RunDtorBB);
|
|
}
|
|
|
|
CGF.EmitCXXDestructorCall(Dtor, Dtor_Complete,
|
|
/*ForVirtualBase=*/false,
|
|
/*Delegating=*/false,
|
|
Loc);
|
|
|
|
if (NRVO) CGF.EmitBlock(SkipDtorBB);
|
|
}
|
|
};
|
|
|
|
struct CallStackRestore final : EHScopeStack::Cleanup {
|
|
Address Stack;
|
|
CallStackRestore(Address Stack) : Stack(Stack) {}
|
|
void Emit(CodeGenFunction &CGF, Flags flags) override {
|
|
llvm::Value *V = CGF.Builder.CreateLoad(Stack);
|
|
llvm::Value *F = CGF.CGM.getIntrinsic(llvm::Intrinsic::stackrestore);
|
|
CGF.Builder.CreateCall(F, V);
|
|
}
|
|
};
|
|
|
|
struct ExtendGCLifetime final : EHScopeStack::Cleanup {
|
|
const VarDecl &Var;
|
|
ExtendGCLifetime(const VarDecl *var) : Var(*var) {}
|
|
|
|
void Emit(CodeGenFunction &CGF, Flags flags) override {
|
|
// Compute the address of the local variable, in case it's a
|
|
// byref or something.
|
|
DeclRefExpr DRE(const_cast<VarDecl*>(&Var), false,
|
|
Var.getType(), VK_LValue, SourceLocation());
|
|
llvm::Value *value = CGF.EmitLoadOfScalar(CGF.EmitDeclRefLValue(&DRE),
|
|
SourceLocation());
|
|
CGF.EmitExtendGCLifetime(value);
|
|
}
|
|
};
|
|
|
|
struct CallCleanupFunction final : EHScopeStack::Cleanup {
|
|
llvm::Constant *CleanupFn;
|
|
const CGFunctionInfo &FnInfo;
|
|
const VarDecl &Var;
|
|
|
|
CallCleanupFunction(llvm::Constant *CleanupFn, const CGFunctionInfo *Info,
|
|
const VarDecl *Var)
|
|
: CleanupFn(CleanupFn), FnInfo(*Info), Var(*Var) {}
|
|
|
|
void Emit(CodeGenFunction &CGF, Flags flags) override {
|
|
DeclRefExpr DRE(const_cast<VarDecl*>(&Var), false,
|
|
Var.getType(), VK_LValue, SourceLocation());
|
|
// Compute the address of the local variable, in case it's a byref
|
|
// or something.
|
|
llvm::Value *Addr = CGF.EmitDeclRefLValue(&DRE).getPointer();
|
|
|
|
// In some cases, the type of the function argument will be different from
|
|
// the type of the pointer. An example of this is
|
|
// void f(void* arg);
|
|
// __attribute__((cleanup(f))) void *g;
|
|
//
|
|
// To fix this we insert a bitcast here.
|
|
QualType ArgTy = FnInfo.arg_begin()->type;
|
|
llvm::Value *Arg =
|
|
CGF.Builder.CreateBitCast(Addr, CGF.ConvertType(ArgTy));
|
|
|
|
CallArgList Args;
|
|
Args.add(RValue::get(Arg),
|
|
CGF.getContext().getPointerType(Var.getType()));
|
|
auto Callee = CGCallee::forDirect(CleanupFn);
|
|
CGF.EmitCall(FnInfo, Callee, ReturnValueSlot(), Args);
|
|
}
|
|
};
|
|
} // end anonymous namespace
|
|
|
|
/// EmitAutoVarWithLifetime - Does the setup required for an automatic
|
|
/// variable with lifetime.
|
|
static void EmitAutoVarWithLifetime(CodeGenFunction &CGF, const VarDecl &var,
|
|
Address addr,
|
|
Qualifiers::ObjCLifetime lifetime) {
|
|
switch (lifetime) {
|
|
case Qualifiers::OCL_None:
|
|
llvm_unreachable("present but none");
|
|
|
|
case Qualifiers::OCL_ExplicitNone:
|
|
// nothing to do
|
|
break;
|
|
|
|
case Qualifiers::OCL_Strong: {
|
|
CodeGenFunction::Destroyer *destroyer =
|
|
(var.hasAttr<ObjCPreciseLifetimeAttr>()
|
|
? CodeGenFunction::destroyARCStrongPrecise
|
|
: CodeGenFunction::destroyARCStrongImprecise);
|
|
|
|
CleanupKind cleanupKind = CGF.getARCCleanupKind();
|
|
CGF.pushDestroy(cleanupKind, addr, var.getType(), destroyer,
|
|
cleanupKind & EHCleanup);
|
|
break;
|
|
}
|
|
case Qualifiers::OCL_Autoreleasing:
|
|
// nothing to do
|
|
break;
|
|
|
|
case Qualifiers::OCL_Weak:
|
|
// __weak objects always get EH cleanups; otherwise, exceptions
|
|
// could cause really nasty crashes instead of mere leaks.
|
|
CGF.pushDestroy(NormalAndEHCleanup, addr, var.getType(),
|
|
CodeGenFunction::destroyARCWeak,
|
|
/*useEHCleanup*/ true);
|
|
break;
|
|
}
|
|
}
|
|
|
|
static bool isAccessedBy(const VarDecl &var, const Stmt *s) {
|
|
if (const Expr *e = dyn_cast<Expr>(s)) {
|
|
// Skip the most common kinds of expressions that make
|
|
// hierarchy-walking expensive.
|
|
s = e = e->IgnoreParenCasts();
|
|
|
|
if (const DeclRefExpr *ref = dyn_cast<DeclRefExpr>(e))
|
|
return (ref->getDecl() == &var);
|
|
if (const BlockExpr *be = dyn_cast<BlockExpr>(e)) {
|
|
const BlockDecl *block = be->getBlockDecl();
|
|
for (const auto &I : block->captures()) {
|
|
if (I.getVariable() == &var)
|
|
return true;
|
|
}
|
|
}
|
|
}
|
|
|
|
for (const Stmt *SubStmt : s->children())
|
|
// SubStmt might be null; as in missing decl or conditional of an if-stmt.
|
|
if (SubStmt && isAccessedBy(var, SubStmt))
|
|
return true;
|
|
|
|
return false;
|
|
}
|
|
|
|
static bool isAccessedBy(const ValueDecl *decl, const Expr *e) {
|
|
if (!decl) return false;
|
|
if (!isa<VarDecl>(decl)) return false;
|
|
const VarDecl *var = cast<VarDecl>(decl);
|
|
return isAccessedBy(*var, e);
|
|
}
|
|
|
|
static bool tryEmitARCCopyWeakInit(CodeGenFunction &CGF,
|
|
const LValue &destLV, const Expr *init) {
|
|
bool needsCast = false;
|
|
|
|
while (auto castExpr = dyn_cast<CastExpr>(init->IgnoreParens())) {
|
|
switch (castExpr->getCastKind()) {
|
|
// Look through casts that don't require representation changes.
|
|
case CK_NoOp:
|
|
case CK_BitCast:
|
|
case CK_BlockPointerToObjCPointerCast:
|
|
needsCast = true;
|
|
break;
|
|
|
|
// If we find an l-value to r-value cast from a __weak variable,
|
|
// emit this operation as a copy or move.
|
|
case CK_LValueToRValue: {
|
|
const Expr *srcExpr = castExpr->getSubExpr();
|
|
if (srcExpr->getType().getObjCLifetime() != Qualifiers::OCL_Weak)
|
|
return false;
|
|
|
|
// Emit the source l-value.
|
|
LValue srcLV = CGF.EmitLValue(srcExpr);
|
|
|
|
// Handle a formal type change to avoid asserting.
|
|
auto srcAddr = srcLV.getAddress();
|
|
if (needsCast) {
|
|
srcAddr = CGF.Builder.CreateElementBitCast(srcAddr,
|
|
destLV.getAddress().getElementType());
|
|
}
|
|
|
|
// If it was an l-value, use objc_copyWeak.
|
|
if (srcExpr->getValueKind() == VK_LValue) {
|
|
CGF.EmitARCCopyWeak(destLV.getAddress(), srcAddr);
|
|
} else {
|
|
assert(srcExpr->getValueKind() == VK_XValue);
|
|
CGF.EmitARCMoveWeak(destLV.getAddress(), srcAddr);
|
|
}
|
|
return true;
|
|
}
|
|
|
|
// Stop at anything else.
|
|
default:
|
|
return false;
|
|
}
|
|
|
|
init = castExpr->getSubExpr();
|
|
}
|
|
return false;
|
|
}
|
|
|
|
static void drillIntoBlockVariable(CodeGenFunction &CGF,
|
|
LValue &lvalue,
|
|
const VarDecl *var) {
|
|
lvalue.setAddress(CGF.emitBlockByrefAddress(lvalue.getAddress(), var));
|
|
}
|
|
|
|
void CodeGenFunction::EmitNullabilityCheck(LValue LHS, llvm::Value *RHS,
|
|
SourceLocation Loc) {
|
|
if (!SanOpts.has(SanitizerKind::NullabilityAssign))
|
|
return;
|
|
|
|
auto Nullability = LHS.getType()->getNullability(getContext());
|
|
if (!Nullability || *Nullability != NullabilityKind::NonNull)
|
|
return;
|
|
|
|
// Check if the right hand side of the assignment is nonnull, if the left
|
|
// hand side must be nonnull.
|
|
SanitizerScope SanScope(this);
|
|
llvm::Value *IsNotNull = Builder.CreateIsNotNull(RHS);
|
|
llvm::Constant *StaticData[] = {
|
|
EmitCheckSourceLocation(Loc), EmitCheckTypeDescriptor(LHS.getType()),
|
|
llvm::ConstantInt::get(Int8Ty, 0), // The LogAlignment info is unused.
|
|
llvm::ConstantInt::get(Int8Ty, TCK_NonnullAssign)};
|
|
EmitCheck({{IsNotNull, SanitizerKind::NullabilityAssign}},
|
|
SanitizerHandler::TypeMismatch, StaticData, RHS);
|
|
}
|
|
|
|
void CodeGenFunction::EmitScalarInit(const Expr *init, const ValueDecl *D,
|
|
LValue lvalue, bool capturedByInit) {
|
|
Qualifiers::ObjCLifetime lifetime = lvalue.getObjCLifetime();
|
|
if (!lifetime) {
|
|
llvm::Value *value = EmitScalarExpr(init);
|
|
if (capturedByInit)
|
|
drillIntoBlockVariable(*this, lvalue, cast<VarDecl>(D));
|
|
EmitNullabilityCheck(lvalue, value, init->getExprLoc());
|
|
EmitStoreThroughLValue(RValue::get(value), lvalue, true);
|
|
return;
|
|
}
|
|
|
|
if (const CXXDefaultInitExpr *DIE = dyn_cast<CXXDefaultInitExpr>(init))
|
|
init = DIE->getExpr();
|
|
|
|
// If we're emitting a value with lifetime, we have to do the
|
|
// initialization *before* we leave the cleanup scopes.
|
|
if (const ExprWithCleanups *ewc = dyn_cast<ExprWithCleanups>(init)) {
|
|
enterFullExpression(ewc);
|
|
init = ewc->getSubExpr();
|
|
}
|
|
CodeGenFunction::RunCleanupsScope Scope(*this);
|
|
|
|
// We have to maintain the illusion that the variable is
|
|
// zero-initialized. If the variable might be accessed in its
|
|
// initializer, zero-initialize before running the initializer, then
|
|
// actually perform the initialization with an assign.
|
|
bool accessedByInit = false;
|
|
if (lifetime != Qualifiers::OCL_ExplicitNone)
|
|
accessedByInit = (capturedByInit || isAccessedBy(D, init));
|
|
if (accessedByInit) {
|
|
LValue tempLV = lvalue;
|
|
// Drill down to the __block object if necessary.
|
|
if (capturedByInit) {
|
|
// We can use a simple GEP for this because it can't have been
|
|
// moved yet.
|
|
tempLV.setAddress(emitBlockByrefAddress(tempLV.getAddress(),
|
|
cast<VarDecl>(D),
|
|
/*follow*/ false));
|
|
}
|
|
|
|
auto ty = cast<llvm::PointerType>(tempLV.getAddress().getElementType());
|
|
llvm::Value *zero = CGM.getNullPointer(ty, tempLV.getType());
|
|
|
|
// If __weak, we want to use a barrier under certain conditions.
|
|
if (lifetime == Qualifiers::OCL_Weak)
|
|
EmitARCInitWeak(tempLV.getAddress(), zero);
|
|
|
|
// Otherwise just do a simple store.
|
|
else
|
|
EmitStoreOfScalar(zero, tempLV, /* isInitialization */ true);
|
|
}
|
|
|
|
// Emit the initializer.
|
|
llvm::Value *value = nullptr;
|
|
|
|
switch (lifetime) {
|
|
case Qualifiers::OCL_None:
|
|
llvm_unreachable("present but none");
|
|
|
|
case Qualifiers::OCL_ExplicitNone:
|
|
value = EmitARCUnsafeUnretainedScalarExpr(init);
|
|
break;
|
|
|
|
case Qualifiers::OCL_Strong: {
|
|
value = EmitARCRetainScalarExpr(init);
|
|
break;
|
|
}
|
|
|
|
case Qualifiers::OCL_Weak: {
|
|
// If it's not accessed by the initializer, try to emit the
|
|
// initialization with a copy or move.
|
|
if (!accessedByInit && tryEmitARCCopyWeakInit(*this, lvalue, init)) {
|
|
return;
|
|
}
|
|
|
|
// No way to optimize a producing initializer into this. It's not
|
|
// worth optimizing for, because the value will immediately
|
|
// disappear in the common case.
|
|
value = EmitScalarExpr(init);
|
|
|
|
if (capturedByInit) drillIntoBlockVariable(*this, lvalue, cast<VarDecl>(D));
|
|
if (accessedByInit)
|
|
EmitARCStoreWeak(lvalue.getAddress(), value, /*ignored*/ true);
|
|
else
|
|
EmitARCInitWeak(lvalue.getAddress(), value);
|
|
return;
|
|
}
|
|
|
|
case Qualifiers::OCL_Autoreleasing:
|
|
value = EmitARCRetainAutoreleaseScalarExpr(init);
|
|
break;
|
|
}
|
|
|
|
if (capturedByInit) drillIntoBlockVariable(*this, lvalue, cast<VarDecl>(D));
|
|
|
|
EmitNullabilityCheck(lvalue, value, init->getExprLoc());
|
|
|
|
// If the variable might have been accessed by its initializer, we
|
|
// might have to initialize with a barrier. We have to do this for
|
|
// both __weak and __strong, but __weak got filtered out above.
|
|
if (accessedByInit && lifetime == Qualifiers::OCL_Strong) {
|
|
llvm::Value *oldValue = EmitLoadOfScalar(lvalue, init->getExprLoc());
|
|
EmitStoreOfScalar(value, lvalue, /* isInitialization */ true);
|
|
EmitARCRelease(oldValue, ARCImpreciseLifetime);
|
|
return;
|
|
}
|
|
|
|
EmitStoreOfScalar(value, lvalue, /* isInitialization */ true);
|
|
}
|
|
|
|
/// canEmitInitWithFewStoresAfterMemset - Decide whether we can emit the
|
|
/// non-zero parts of the specified initializer with equal or fewer than
|
|
/// NumStores scalar stores.
|
|
static bool canEmitInitWithFewStoresAfterMemset(llvm::Constant *Init,
|
|
unsigned &NumStores) {
|
|
// Zero and Undef never requires any extra stores.
|
|
if (isa<llvm::ConstantAggregateZero>(Init) ||
|
|
isa<llvm::ConstantPointerNull>(Init) ||
|
|
isa<llvm::UndefValue>(Init))
|
|
return true;
|
|
if (isa<llvm::ConstantInt>(Init) || isa<llvm::ConstantFP>(Init) ||
|
|
isa<llvm::ConstantVector>(Init) || isa<llvm::BlockAddress>(Init) ||
|
|
isa<llvm::ConstantExpr>(Init))
|
|
return Init->isNullValue() || NumStores--;
|
|
|
|
// See if we can emit each element.
|
|
if (isa<llvm::ConstantArray>(Init) || isa<llvm::ConstantStruct>(Init)) {
|
|
for (unsigned i = 0, e = Init->getNumOperands(); i != e; ++i) {
|
|
llvm::Constant *Elt = cast<llvm::Constant>(Init->getOperand(i));
|
|
if (!canEmitInitWithFewStoresAfterMemset(Elt, NumStores))
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
if (llvm::ConstantDataSequential *CDS =
|
|
dyn_cast<llvm::ConstantDataSequential>(Init)) {
|
|
for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
|
|
llvm::Constant *Elt = CDS->getElementAsConstant(i);
|
|
if (!canEmitInitWithFewStoresAfterMemset(Elt, NumStores))
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
// Anything else is hard and scary.
|
|
return false;
|
|
}
|
|
|
|
/// emitStoresForInitAfterMemset - For inits that
|
|
/// canEmitInitWithFewStoresAfterMemset returned true for, emit the scalar
|
|
/// stores that would be required.
|
|
static void emitStoresForInitAfterMemset(llvm::Constant *Init, llvm::Value *Loc,
|
|
bool isVolatile, CGBuilderTy &Builder) {
|
|
assert(!Init->isNullValue() && !isa<llvm::UndefValue>(Init) &&
|
|
"called emitStoresForInitAfterMemset for zero or undef value.");
|
|
|
|
if (isa<llvm::ConstantInt>(Init) || isa<llvm::ConstantFP>(Init) ||
|
|
isa<llvm::ConstantVector>(Init) || isa<llvm::BlockAddress>(Init) ||
|
|
isa<llvm::ConstantExpr>(Init)) {
|
|
Builder.CreateDefaultAlignedStore(Init, Loc, isVolatile);
|
|
return;
|
|
}
|
|
|
|
if (llvm::ConstantDataSequential *CDS =
|
|
dyn_cast<llvm::ConstantDataSequential>(Init)) {
|
|
for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
|
|
llvm::Constant *Elt = CDS->getElementAsConstant(i);
|
|
|
|
// If necessary, get a pointer to the element and emit it.
|
|
if (!Elt->isNullValue() && !isa<llvm::UndefValue>(Elt))
|
|
emitStoresForInitAfterMemset(
|
|
Elt, Builder.CreateConstGEP2_32(Init->getType(), Loc, 0, i),
|
|
isVolatile, Builder);
|
|
}
|
|
return;
|
|
}
|
|
|
|
assert((isa<llvm::ConstantStruct>(Init) || isa<llvm::ConstantArray>(Init)) &&
|
|
"Unknown value type!");
|
|
|
|
for (unsigned i = 0, e = Init->getNumOperands(); i != e; ++i) {
|
|
llvm::Constant *Elt = cast<llvm::Constant>(Init->getOperand(i));
|
|
|
|
// If necessary, get a pointer to the element and emit it.
|
|
if (!Elt->isNullValue() && !isa<llvm::UndefValue>(Elt))
|
|
emitStoresForInitAfterMemset(
|
|
Elt, Builder.CreateConstGEP2_32(Init->getType(), Loc, 0, i),
|
|
isVolatile, Builder);
|
|
}
|
|
}
|
|
|
|
/// shouldUseMemSetPlusStoresToInitialize - Decide whether we should use memset
|
|
/// plus some stores to initialize a local variable instead of using a memcpy
|
|
/// from a constant global. It is beneficial to use memset if the global is all
|
|
/// zeros, or mostly zeros and large.
|
|
static bool shouldUseMemSetPlusStoresToInitialize(llvm::Constant *Init,
|
|
uint64_t GlobalSize) {
|
|
// If a global is all zeros, always use a memset.
|
|
if (isa<llvm::ConstantAggregateZero>(Init)) return true;
|
|
|
|
// If a non-zero global is <= 32 bytes, always use a memcpy. If it is large,
|
|
// do it if it will require 6 or fewer scalar stores.
|
|
// TODO: Should budget depends on the size? Avoiding a large global warrants
|
|
// plopping in more stores.
|
|
unsigned StoreBudget = 6;
|
|
uint64_t SizeLimit = 32;
|
|
|
|
return GlobalSize > SizeLimit &&
|
|
canEmitInitWithFewStoresAfterMemset(Init, StoreBudget);
|
|
}
|
|
|
|
/// EmitAutoVarDecl - Emit code and set up an entry in LocalDeclMap for a
|
|
/// variable declaration with auto, register, or no storage class specifier.
|
|
/// These turn into simple stack objects, or GlobalValues depending on target.
|
|
void CodeGenFunction::EmitAutoVarDecl(const VarDecl &D) {
|
|
AutoVarEmission emission = EmitAutoVarAlloca(D);
|
|
EmitAutoVarInit(emission);
|
|
EmitAutoVarCleanups(emission);
|
|
}
|
|
|
|
/// Emit a lifetime.begin marker if some criteria are satisfied.
|
|
/// \return a pointer to the temporary size Value if a marker was emitted, null
|
|
/// otherwise
|
|
llvm::Value *CodeGenFunction::EmitLifetimeStart(uint64_t Size,
|
|
llvm::Value *Addr) {
|
|
if (!ShouldEmitLifetimeMarkers)
|
|
return nullptr;
|
|
|
|
llvm::Value *SizeV = llvm::ConstantInt::get(Int64Ty, Size);
|
|
Addr = Builder.CreateBitCast(Addr, AllocaInt8PtrTy);
|
|
llvm::CallInst *C =
|
|
Builder.CreateCall(CGM.getLLVMLifetimeStartFn(), {SizeV, Addr});
|
|
C->setDoesNotThrow();
|
|
return SizeV;
|
|
}
|
|
|
|
void CodeGenFunction::EmitLifetimeEnd(llvm::Value *Size, llvm::Value *Addr) {
|
|
Addr = Builder.CreateBitCast(Addr, AllocaInt8PtrTy);
|
|
llvm::CallInst *C =
|
|
Builder.CreateCall(CGM.getLLVMLifetimeEndFn(), {Size, Addr});
|
|
C->setDoesNotThrow();
|
|
}
|
|
|
|
/// EmitAutoVarAlloca - Emit the alloca and debug information for a
|
|
/// local variable. Does not emit initialization or destruction.
|
|
CodeGenFunction::AutoVarEmission
|
|
CodeGenFunction::EmitAutoVarAlloca(const VarDecl &D) {
|
|
QualType Ty = D.getType();
|
|
assert(
|
|
Ty.getAddressSpace() == LangAS::Default ||
|
|
(Ty.getAddressSpace() == LangAS::opencl_private && getLangOpts().OpenCL));
|
|
|
|
AutoVarEmission emission(D);
|
|
|
|
bool isByRef = D.hasAttr<BlocksAttr>();
|
|
emission.IsByRef = isByRef;
|
|
|
|
CharUnits alignment = getContext().getDeclAlign(&D);
|
|
|
|
// If the type is variably-modified, emit all the VLA sizes for it.
|
|
if (Ty->isVariablyModifiedType())
|
|
EmitVariablyModifiedType(Ty);
|
|
|
|
Address address = Address::invalid();
|
|
if (Ty->isConstantSizeType()) {
|
|
bool NRVO = getLangOpts().ElideConstructors &&
|
|
D.isNRVOVariable();
|
|
|
|
// If this value is an array or struct with a statically determinable
|
|
// constant initializer, there are optimizations we can do.
|
|
//
|
|
// TODO: We should constant-evaluate the initializer of any variable,
|
|
// as long as it is initialized by a constant expression. Currently,
|
|
// isConstantInitializer produces wrong answers for structs with
|
|
// reference or bitfield members, and a few other cases, and checking
|
|
// for POD-ness protects us from some of these.
|
|
if (D.getInit() && (Ty->isArrayType() || Ty->isRecordType()) &&
|
|
(D.isConstexpr() ||
|
|
((Ty.isPODType(getContext()) ||
|
|
getContext().getBaseElementType(Ty)->isObjCObjectPointerType()) &&
|
|
D.getInit()->isConstantInitializer(getContext(), false)))) {
|
|
|
|
// If the variable's a const type, and it's neither an NRVO
|
|
// candidate nor a __block variable and has no mutable members,
|
|
// emit it as a global instead.
|
|
// Exception is if a variable is located in non-constant address space
|
|
// in OpenCL.
|
|
if ((!getLangOpts().OpenCL ||
|
|
Ty.getAddressSpace() == LangAS::opencl_constant) &&
|
|
(CGM.getCodeGenOpts().MergeAllConstants && !NRVO && !isByRef &&
|
|
CGM.isTypeConstant(Ty, true))) {
|
|
EmitStaticVarDecl(D, llvm::GlobalValue::InternalLinkage);
|
|
|
|
// Signal this condition to later callbacks.
|
|
emission.Addr = Address::invalid();
|
|
assert(emission.wasEmittedAsGlobal());
|
|
return emission;
|
|
}
|
|
|
|
// Otherwise, tell the initialization code that we're in this case.
|
|
emission.IsConstantAggregate = true;
|
|
}
|
|
|
|
// A normal fixed sized variable becomes an alloca in the entry block,
|
|
// unless it's an NRVO variable.
|
|
|
|
if (NRVO) {
|
|
// The named return value optimization: allocate this variable in the
|
|
// return slot, so that we can elide the copy when returning this
|
|
// variable (C++0x [class.copy]p34).
|
|
address = ReturnValue;
|
|
|
|
if (const RecordType *RecordTy = Ty->getAs<RecordType>()) {
|
|
if (!cast<CXXRecordDecl>(RecordTy->getDecl())->hasTrivialDestructor()) {
|
|
// Create a flag that is used to indicate when the NRVO was applied
|
|
// to this variable. Set it to zero to indicate that NRVO was not
|
|
// applied.
|
|
llvm::Value *Zero = Builder.getFalse();
|
|
Address NRVOFlag =
|
|
CreateTempAlloca(Zero->getType(), CharUnits::One(), "nrvo");
|
|
EnsureInsertPoint();
|
|
Builder.CreateStore(Zero, NRVOFlag);
|
|
|
|
// Record the NRVO flag for this variable.
|
|
NRVOFlags[&D] = NRVOFlag.getPointer();
|
|
emission.NRVOFlag = NRVOFlag.getPointer();
|
|
}
|
|
}
|
|
} else {
|
|
CharUnits allocaAlignment;
|
|
llvm::Type *allocaTy;
|
|
if (isByRef) {
|
|
auto &byrefInfo = getBlockByrefInfo(&D);
|
|
allocaTy = byrefInfo.Type;
|
|
allocaAlignment = byrefInfo.ByrefAlignment;
|
|
} else {
|
|
allocaTy = ConvertTypeForMem(Ty);
|
|
allocaAlignment = alignment;
|
|
}
|
|
|
|
// Create the alloca. Note that we set the name separately from
|
|
// building the instruction so that it's there even in no-asserts
|
|
// builds.
|
|
address = CreateTempAlloca(allocaTy, allocaAlignment, D.getName());
|
|
|
|
// Don't emit lifetime markers for MSVC catch parameters. The lifetime of
|
|
// the catch parameter starts in the catchpad instruction, and we can't
|
|
// insert code in those basic blocks.
|
|
bool IsMSCatchParam =
|
|
D.isExceptionVariable() && getTarget().getCXXABI().isMicrosoft();
|
|
|
|
// Emit a lifetime intrinsic if meaningful. There's no point in doing this
|
|
// if we don't have a valid insertion point (?).
|
|
if (HaveInsertPoint() && !IsMSCatchParam) {
|
|
// If there's a jump into the lifetime of this variable, its lifetime
|
|
// gets broken up into several regions in IR, which requires more work
|
|
// to handle correctly. For now, just omit the intrinsics; this is a
|
|
// rare case, and it's better to just be conservatively correct.
|
|
// PR28267.
|
|
//
|
|
// We have to do this in all language modes if there's a jump past the
|
|
// declaration. We also have to do it in C if there's a jump to an
|
|
// earlier point in the current block because non-VLA lifetimes begin as
|
|
// soon as the containing block is entered, not when its variables
|
|
// actually come into scope; suppressing the lifetime annotations
|
|
// completely in this case is unnecessarily pessimistic, but again, this
|
|
// is rare.
|
|
if (!Bypasses.IsBypassed(&D) &&
|
|
!(!getLangOpts().CPlusPlus && hasLabelBeenSeenInCurrentScope())) {
|
|
uint64_t size = CGM.getDataLayout().getTypeAllocSize(allocaTy);
|
|
emission.SizeForLifetimeMarkers =
|
|
EmitLifetimeStart(size, address.getPointer());
|
|
}
|
|
} else {
|
|
assert(!emission.useLifetimeMarkers());
|
|
}
|
|
}
|
|
} else {
|
|
EnsureInsertPoint();
|
|
|
|
if (!DidCallStackSave) {
|
|
// Save the stack.
|
|
Address Stack =
|
|
CreateTempAlloca(Int8PtrTy, getPointerAlign(), "saved_stack");
|
|
|
|
llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::stacksave);
|
|
llvm::Value *V = Builder.CreateCall(F);
|
|
Builder.CreateStore(V, Stack);
|
|
|
|
DidCallStackSave = true;
|
|
|
|
// Push a cleanup block and restore the stack there.
|
|
// FIXME: in general circumstances, this should be an EH cleanup.
|
|
pushStackRestore(NormalCleanup, Stack);
|
|
}
|
|
|
|
llvm::Value *elementCount;
|
|
QualType elementType;
|
|
std::tie(elementCount, elementType) = getVLASize(Ty);
|
|
|
|
llvm::Type *llvmTy = ConvertTypeForMem(elementType);
|
|
|
|
// Allocate memory for the array.
|
|
address = CreateTempAlloca(llvmTy, alignment, "vla", elementCount);
|
|
}
|
|
|
|
setAddrOfLocalVar(&D, address);
|
|
emission.Addr = address;
|
|
|
|
// Emit debug info for local var declaration.
|
|
if (HaveInsertPoint())
|
|
if (CGDebugInfo *DI = getDebugInfo()) {
|
|
if (CGM.getCodeGenOpts().getDebugInfo() >=
|
|
codegenoptions::LimitedDebugInfo) {
|
|
DI->setLocation(D.getLocation());
|
|
DI->EmitDeclareOfAutoVariable(&D, address.getPointer(), Builder);
|
|
}
|
|
}
|
|
|
|
if (D.hasAttr<AnnotateAttr>())
|
|
EmitVarAnnotations(&D, address.getPointer());
|
|
|
|
// Make sure we call @llvm.lifetime.end.
|
|
if (emission.useLifetimeMarkers())
|
|
EHStack.pushCleanup<CallLifetimeEnd>(NormalEHLifetimeMarker,
|
|
emission.getAllocatedAddress(),
|
|
emission.getSizeForLifetimeMarkers());
|
|
|
|
return emission;
|
|
}
|
|
|
|
/// Determines whether the given __block variable is potentially
|
|
/// captured by the given expression.
|
|
static bool isCapturedBy(const VarDecl &var, const Expr *e) {
|
|
// Skip the most common kinds of expressions that make
|
|
// hierarchy-walking expensive.
|
|
e = e->IgnoreParenCasts();
|
|
|
|
if (const BlockExpr *be = dyn_cast<BlockExpr>(e)) {
|
|
const BlockDecl *block = be->getBlockDecl();
|
|
for (const auto &I : block->captures()) {
|
|
if (I.getVariable() == &var)
|
|
return true;
|
|
}
|
|
|
|
// No need to walk into the subexpressions.
|
|
return false;
|
|
}
|
|
|
|
if (const StmtExpr *SE = dyn_cast<StmtExpr>(e)) {
|
|
const CompoundStmt *CS = SE->getSubStmt();
|
|
for (const auto *BI : CS->body())
|
|
if (const auto *E = dyn_cast<Expr>(BI)) {
|
|
if (isCapturedBy(var, E))
|
|
return true;
|
|
}
|
|
else if (const auto *DS = dyn_cast<DeclStmt>(BI)) {
|
|
// special case declarations
|
|
for (const auto *I : DS->decls()) {
|
|
if (const auto *VD = dyn_cast<VarDecl>((I))) {
|
|
const Expr *Init = VD->getInit();
|
|
if (Init && isCapturedBy(var, Init))
|
|
return true;
|
|
}
|
|
}
|
|
}
|
|
else
|
|
// FIXME. Make safe assumption assuming arbitrary statements cause capturing.
|
|
// Later, provide code to poke into statements for capture analysis.
|
|
return true;
|
|
return false;
|
|
}
|
|
|
|
for (const Stmt *SubStmt : e->children())
|
|
if (isCapturedBy(var, cast<Expr>(SubStmt)))
|
|
return true;
|
|
|
|
return false;
|
|
}
|
|
|
|
/// \brief Determine whether the given initializer is trivial in the sense
|
|
/// that it requires no code to be generated.
|
|
bool CodeGenFunction::isTrivialInitializer(const Expr *Init) {
|
|
if (!Init)
|
|
return true;
|
|
|
|
if (const CXXConstructExpr *Construct = dyn_cast<CXXConstructExpr>(Init))
|
|
if (CXXConstructorDecl *Constructor = Construct->getConstructor())
|
|
if (Constructor->isTrivial() &&
|
|
Constructor->isDefaultConstructor() &&
|
|
!Construct->requiresZeroInitialization())
|
|
return true;
|
|
|
|
return false;
|
|
}
|
|
|
|
void CodeGenFunction::EmitAutoVarInit(const AutoVarEmission &emission) {
|
|
assert(emission.Variable && "emission was not valid!");
|
|
|
|
// If this was emitted as a global constant, we're done.
|
|
if (emission.wasEmittedAsGlobal()) return;
|
|
|
|
const VarDecl &D = *emission.Variable;
|
|
auto DL = ApplyDebugLocation::CreateDefaultArtificial(*this, D.getLocation());
|
|
QualType type = D.getType();
|
|
|
|
// If this local has an initializer, emit it now.
|
|
const Expr *Init = D.getInit();
|
|
|
|
// If we are at an unreachable point, we don't need to emit the initializer
|
|
// unless it contains a label.
|
|
if (!HaveInsertPoint()) {
|
|
if (!Init || !ContainsLabel(Init)) return;
|
|
EnsureInsertPoint();
|
|
}
|
|
|
|
// Initialize the structure of a __block variable.
|
|
if (emission.IsByRef)
|
|
emitByrefStructureInit(emission);
|
|
|
|
if (isTrivialInitializer(Init))
|
|
return;
|
|
|
|
// Check whether this is a byref variable that's potentially
|
|
// captured and moved by its own initializer. If so, we'll need to
|
|
// emit the initializer first, then copy into the variable.
|
|
bool capturedByInit = emission.IsByRef && isCapturedBy(D, Init);
|
|
|
|
Address Loc =
|
|
capturedByInit ? emission.Addr : emission.getObjectAddress(*this);
|
|
|
|
llvm::Constant *constant = nullptr;
|
|
if (emission.IsConstantAggregate || D.isConstexpr()) {
|
|
assert(!capturedByInit && "constant init contains a capturing block?");
|
|
constant = ConstantEmitter(*this).tryEmitAbstractForInitializer(D);
|
|
}
|
|
|
|
if (!constant) {
|
|
LValue lv = MakeAddrLValue(Loc, type);
|
|
lv.setNonGC(true);
|
|
return EmitExprAsInit(Init, &D, lv, capturedByInit);
|
|
}
|
|
|
|
if (!emission.IsConstantAggregate) {
|
|
// For simple scalar/complex initialization, store the value directly.
|
|
LValue lv = MakeAddrLValue(Loc, type);
|
|
lv.setNonGC(true);
|
|
return EmitStoreThroughLValue(RValue::get(constant), lv, true);
|
|
}
|
|
|
|
// If this is a simple aggregate initialization, we can optimize it
|
|
// in various ways.
|
|
bool isVolatile = type.isVolatileQualified();
|
|
|
|
llvm::Value *SizeVal =
|
|
llvm::ConstantInt::get(IntPtrTy,
|
|
getContext().getTypeSizeInChars(type).getQuantity());
|
|
|
|
llvm::Type *BP = AllocaInt8PtrTy;
|
|
if (Loc.getType() != BP)
|
|
Loc = Builder.CreateBitCast(Loc, BP);
|
|
|
|
// If the initializer is all or mostly zeros, codegen with memset then do
|
|
// a few stores afterward.
|
|
if (shouldUseMemSetPlusStoresToInitialize(constant,
|
|
CGM.getDataLayout().getTypeAllocSize(constant->getType()))) {
|
|
Builder.CreateMemSet(Loc, llvm::ConstantInt::get(Int8Ty, 0), SizeVal,
|
|
isVolatile);
|
|
// Zero and undef don't require a stores.
|
|
if (!constant->isNullValue() && !isa<llvm::UndefValue>(constant)) {
|
|
Loc = Builder.CreateBitCast(Loc, constant->getType()->getPointerTo());
|
|
emitStoresForInitAfterMemset(constant, Loc.getPointer(),
|
|
isVolatile, Builder);
|
|
}
|
|
} else {
|
|
// Otherwise, create a temporary global with the initializer then
|
|
// memcpy from the global to the alloca.
|
|
std::string Name = getStaticDeclName(CGM, D);
|
|
unsigned AS = 0;
|
|
if (getLangOpts().OpenCL) {
|
|
AS = CGM.getContext().getTargetAddressSpace(LangAS::opencl_constant);
|
|
BP = llvm::PointerType::getInt8PtrTy(getLLVMContext(), AS);
|
|
}
|
|
llvm::GlobalVariable *GV =
|
|
new llvm::GlobalVariable(CGM.getModule(), constant->getType(), true,
|
|
llvm::GlobalValue::PrivateLinkage,
|
|
constant, Name, nullptr,
|
|
llvm::GlobalValue::NotThreadLocal, AS);
|
|
GV->setAlignment(Loc.getAlignment().getQuantity());
|
|
GV->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
|
|
|
|
Address SrcPtr = Address(GV, Loc.getAlignment());
|
|
if (SrcPtr.getType() != BP)
|
|
SrcPtr = Builder.CreateBitCast(SrcPtr, BP);
|
|
|
|
Builder.CreateMemCpy(Loc, SrcPtr, SizeVal, isVolatile);
|
|
}
|
|
}
|
|
|
|
/// Emit an expression as an initializer for a variable at the given
|
|
/// location. The expression is not necessarily the normal
|
|
/// initializer for the variable, and the address is not necessarily
|
|
/// its normal location.
|
|
///
|
|
/// \param init the initializing expression
|
|
/// \param var the variable to act as if we're initializing
|
|
/// \param loc the address to initialize; its type is a pointer
|
|
/// to the LLVM mapping of the variable's type
|
|
/// \param alignment the alignment of the address
|
|
/// \param capturedByInit true if the variable is a __block variable
|
|
/// whose address is potentially changed by the initializer
|
|
void CodeGenFunction::EmitExprAsInit(const Expr *init, const ValueDecl *D,
|
|
LValue lvalue, bool capturedByInit) {
|
|
QualType type = D->getType();
|
|
|
|
if (type->isReferenceType()) {
|
|
RValue rvalue = EmitReferenceBindingToExpr(init);
|
|
if (capturedByInit)
|
|
drillIntoBlockVariable(*this, lvalue, cast<VarDecl>(D));
|
|
EmitStoreThroughLValue(rvalue, lvalue, true);
|
|
return;
|
|
}
|
|
switch (getEvaluationKind(type)) {
|
|
case TEK_Scalar:
|
|
EmitScalarInit(init, D, lvalue, capturedByInit);
|
|
return;
|
|
case TEK_Complex: {
|
|
ComplexPairTy complex = EmitComplexExpr(init);
|
|
if (capturedByInit)
|
|
drillIntoBlockVariable(*this, lvalue, cast<VarDecl>(D));
|
|
EmitStoreOfComplex(complex, lvalue, /*init*/ true);
|
|
return;
|
|
}
|
|
case TEK_Aggregate:
|
|
if (type->isAtomicType()) {
|
|
EmitAtomicInit(const_cast<Expr*>(init), lvalue);
|
|
} else {
|
|
// TODO: how can we delay here if D is captured by its initializer?
|
|
EmitAggExpr(init, AggValueSlot::forLValue(lvalue,
|
|
AggValueSlot::IsDestructed,
|
|
AggValueSlot::DoesNotNeedGCBarriers,
|
|
AggValueSlot::IsNotAliased));
|
|
}
|
|
return;
|
|
}
|
|
llvm_unreachable("bad evaluation kind");
|
|
}
|
|
|
|
/// Enter a destroy cleanup for the given local variable.
|
|
void CodeGenFunction::emitAutoVarTypeCleanup(
|
|
const CodeGenFunction::AutoVarEmission &emission,
|
|
QualType::DestructionKind dtorKind) {
|
|
assert(dtorKind != QualType::DK_none);
|
|
|
|
// Note that for __block variables, we want to destroy the
|
|
// original stack object, not the possibly forwarded object.
|
|
Address addr = emission.getObjectAddress(*this);
|
|
|
|
const VarDecl *var = emission.Variable;
|
|
QualType type = var->getType();
|
|
|
|
CleanupKind cleanupKind = NormalAndEHCleanup;
|
|
CodeGenFunction::Destroyer *destroyer = nullptr;
|
|
|
|
switch (dtorKind) {
|
|
case QualType::DK_none:
|
|
llvm_unreachable("no cleanup for trivially-destructible variable");
|
|
|
|
case QualType::DK_cxx_destructor:
|
|
// If there's an NRVO flag on the emission, we need a different
|
|
// cleanup.
|
|
if (emission.NRVOFlag) {
|
|
assert(!type->isArrayType());
|
|
CXXDestructorDecl *dtor = type->getAsCXXRecordDecl()->getDestructor();
|
|
EHStack.pushCleanup<DestroyNRVOVariable>(cleanupKind, addr,
|
|
dtor, emission.NRVOFlag);
|
|
return;
|
|
}
|
|
break;
|
|
|
|
case QualType::DK_objc_strong_lifetime:
|
|
// Suppress cleanups for pseudo-strong variables.
|
|
if (var->isARCPseudoStrong()) return;
|
|
|
|
// Otherwise, consider whether to use an EH cleanup or not.
|
|
cleanupKind = getARCCleanupKind();
|
|
|
|
// Use the imprecise destroyer by default.
|
|
if (!var->hasAttr<ObjCPreciseLifetimeAttr>())
|
|
destroyer = CodeGenFunction::destroyARCStrongImprecise;
|
|
break;
|
|
|
|
case QualType::DK_objc_weak_lifetime:
|
|
break;
|
|
}
|
|
|
|
// If we haven't chosen a more specific destroyer, use the default.
|
|
if (!destroyer) destroyer = getDestroyer(dtorKind);
|
|
|
|
// Use an EH cleanup in array destructors iff the destructor itself
|
|
// is being pushed as an EH cleanup.
|
|
bool useEHCleanup = (cleanupKind & EHCleanup);
|
|
EHStack.pushCleanup<DestroyObject>(cleanupKind, addr, type, destroyer,
|
|
useEHCleanup);
|
|
}
|
|
|
|
void CodeGenFunction::EmitAutoVarCleanups(const AutoVarEmission &emission) {
|
|
assert(emission.Variable && "emission was not valid!");
|
|
|
|
// If this was emitted as a global constant, we're done.
|
|
if (emission.wasEmittedAsGlobal()) return;
|
|
|
|
// If we don't have an insertion point, we're done. Sema prevents
|
|
// us from jumping into any of these scopes anyway.
|
|
if (!HaveInsertPoint()) return;
|
|
|
|
const VarDecl &D = *emission.Variable;
|
|
|
|
// Check the type for a cleanup.
|
|
if (QualType::DestructionKind dtorKind = D.getType().isDestructedType())
|
|
emitAutoVarTypeCleanup(emission, dtorKind);
|
|
|
|
// In GC mode, honor objc_precise_lifetime.
|
|
if (getLangOpts().getGC() != LangOptions::NonGC &&
|
|
D.hasAttr<ObjCPreciseLifetimeAttr>()) {
|
|
EHStack.pushCleanup<ExtendGCLifetime>(NormalCleanup, &D);
|
|
}
|
|
|
|
// Handle the cleanup attribute.
|
|
if (const CleanupAttr *CA = D.getAttr<CleanupAttr>()) {
|
|
const FunctionDecl *FD = CA->getFunctionDecl();
|
|
|
|
llvm::Constant *F = CGM.GetAddrOfFunction(FD);
|
|
assert(F && "Could not find function!");
|
|
|
|
const CGFunctionInfo &Info = CGM.getTypes().arrangeFunctionDeclaration(FD);
|
|
EHStack.pushCleanup<CallCleanupFunction>(NormalAndEHCleanup, F, &Info, &D);
|
|
}
|
|
|
|
// If this is a block variable, call _Block_object_destroy
|
|
// (on the unforwarded address).
|
|
if (emission.IsByRef)
|
|
enterByrefCleanup(emission);
|
|
}
|
|
|
|
CodeGenFunction::Destroyer *
|
|
CodeGenFunction::getDestroyer(QualType::DestructionKind kind) {
|
|
switch (kind) {
|
|
case QualType::DK_none: llvm_unreachable("no destroyer for trivial dtor");
|
|
case QualType::DK_cxx_destructor:
|
|
return destroyCXXObject;
|
|
case QualType::DK_objc_strong_lifetime:
|
|
return destroyARCStrongPrecise;
|
|
case QualType::DK_objc_weak_lifetime:
|
|
return destroyARCWeak;
|
|
}
|
|
llvm_unreachable("Unknown DestructionKind");
|
|
}
|
|
|
|
/// pushEHDestroy - Push the standard destructor for the given type as
|
|
/// an EH-only cleanup.
|
|
void CodeGenFunction::pushEHDestroy(QualType::DestructionKind dtorKind,
|
|
Address addr, QualType type) {
|
|
assert(dtorKind && "cannot push destructor for trivial type");
|
|
assert(needsEHCleanup(dtorKind));
|
|
|
|
pushDestroy(EHCleanup, addr, type, getDestroyer(dtorKind), true);
|
|
}
|
|
|
|
/// pushDestroy - Push the standard destructor for the given type as
|
|
/// at least a normal cleanup.
|
|
void CodeGenFunction::pushDestroy(QualType::DestructionKind dtorKind,
|
|
Address addr, QualType type) {
|
|
assert(dtorKind && "cannot push destructor for trivial type");
|
|
|
|
CleanupKind cleanupKind = getCleanupKind(dtorKind);
|
|
pushDestroy(cleanupKind, addr, type, getDestroyer(dtorKind),
|
|
cleanupKind & EHCleanup);
|
|
}
|
|
|
|
void CodeGenFunction::pushDestroy(CleanupKind cleanupKind, Address addr,
|
|
QualType type, Destroyer *destroyer,
|
|
bool useEHCleanupForArray) {
|
|
pushFullExprCleanup<DestroyObject>(cleanupKind, addr, type,
|
|
destroyer, useEHCleanupForArray);
|
|
}
|
|
|
|
void CodeGenFunction::pushStackRestore(CleanupKind Kind, Address SPMem) {
|
|
EHStack.pushCleanup<CallStackRestore>(Kind, SPMem);
|
|
}
|
|
|
|
void CodeGenFunction::pushLifetimeExtendedDestroy(
|
|
CleanupKind cleanupKind, Address addr, QualType type,
|
|
Destroyer *destroyer, bool useEHCleanupForArray) {
|
|
assert(!isInConditionalBranch() &&
|
|
"performing lifetime extension from within conditional");
|
|
|
|
// Push an EH-only cleanup for the object now.
|
|
// FIXME: When popping normal cleanups, we need to keep this EH cleanup
|
|
// around in case a temporary's destructor throws an exception.
|
|
if (cleanupKind & EHCleanup)
|
|
EHStack.pushCleanup<DestroyObject>(
|
|
static_cast<CleanupKind>(cleanupKind & ~NormalCleanup), addr, type,
|
|
destroyer, useEHCleanupForArray);
|
|
|
|
// Remember that we need to push a full cleanup for the object at the
|
|
// end of the full-expression.
|
|
pushCleanupAfterFullExpr<DestroyObject>(
|
|
cleanupKind, addr, type, destroyer, useEHCleanupForArray);
|
|
}
|
|
|
|
/// emitDestroy - Immediately perform the destruction of the given
|
|
/// object.
|
|
///
|
|
/// \param addr - the address of the object; a type*
|
|
/// \param type - the type of the object; if an array type, all
|
|
/// objects are destroyed in reverse order
|
|
/// \param destroyer - the function to call to destroy individual
|
|
/// elements
|
|
/// \param useEHCleanupForArray - whether an EH cleanup should be
|
|
/// used when destroying array elements, in case one of the
|
|
/// destructions throws an exception
|
|
void CodeGenFunction::emitDestroy(Address addr, QualType type,
|
|
Destroyer *destroyer,
|
|
bool useEHCleanupForArray) {
|
|
const ArrayType *arrayType = getContext().getAsArrayType(type);
|
|
if (!arrayType)
|
|
return destroyer(*this, addr, type);
|
|
|
|
llvm::Value *length = emitArrayLength(arrayType, type, addr);
|
|
|
|
CharUnits elementAlign =
|
|
addr.getAlignment()
|
|
.alignmentOfArrayElement(getContext().getTypeSizeInChars(type));
|
|
|
|
// Normally we have to check whether the array is zero-length.
|
|
bool checkZeroLength = true;
|
|
|
|
// But if the array length is constant, we can suppress that.
|
|
if (llvm::ConstantInt *constLength = dyn_cast<llvm::ConstantInt>(length)) {
|
|
// ...and if it's constant zero, we can just skip the entire thing.
|
|
if (constLength->isZero()) return;
|
|
checkZeroLength = false;
|
|
}
|
|
|
|
llvm::Value *begin = addr.getPointer();
|
|
llvm::Value *end = Builder.CreateInBoundsGEP(begin, length);
|
|
emitArrayDestroy(begin, end, type, elementAlign, destroyer,
|
|
checkZeroLength, useEHCleanupForArray);
|
|
}
|
|
|
|
/// emitArrayDestroy - Destroys all the elements of the given array,
|
|
/// beginning from last to first. The array cannot be zero-length.
|
|
///
|
|
/// \param begin - a type* denoting the first element of the array
|
|
/// \param end - a type* denoting one past the end of the array
|
|
/// \param elementType - the element type of the array
|
|
/// \param destroyer - the function to call to destroy elements
|
|
/// \param useEHCleanup - whether to push an EH cleanup to destroy
|
|
/// the remaining elements in case the destruction of a single
|
|
/// element throws
|
|
void CodeGenFunction::emitArrayDestroy(llvm::Value *begin,
|
|
llvm::Value *end,
|
|
QualType elementType,
|
|
CharUnits elementAlign,
|
|
Destroyer *destroyer,
|
|
bool checkZeroLength,
|
|
bool useEHCleanup) {
|
|
assert(!elementType->isArrayType());
|
|
|
|
// The basic structure here is a do-while loop, because we don't
|
|
// need to check for the zero-element case.
|
|
llvm::BasicBlock *bodyBB = createBasicBlock("arraydestroy.body");
|
|
llvm::BasicBlock *doneBB = createBasicBlock("arraydestroy.done");
|
|
|
|
if (checkZeroLength) {
|
|
llvm::Value *isEmpty = Builder.CreateICmpEQ(begin, end,
|
|
"arraydestroy.isempty");
|
|
Builder.CreateCondBr(isEmpty, doneBB, bodyBB);
|
|
}
|
|
|
|
// Enter the loop body, making that address the current address.
|
|
llvm::BasicBlock *entryBB = Builder.GetInsertBlock();
|
|
EmitBlock(bodyBB);
|
|
llvm::PHINode *elementPast =
|
|
Builder.CreatePHI(begin->getType(), 2, "arraydestroy.elementPast");
|
|
elementPast->addIncoming(end, entryBB);
|
|
|
|
// Shift the address back by one element.
|
|
llvm::Value *negativeOne = llvm::ConstantInt::get(SizeTy, -1, true);
|
|
llvm::Value *element = Builder.CreateInBoundsGEP(elementPast, negativeOne,
|
|
"arraydestroy.element");
|
|
|
|
if (useEHCleanup)
|
|
pushRegularPartialArrayCleanup(begin, element, elementType, elementAlign,
|
|
destroyer);
|
|
|
|
// Perform the actual destruction there.
|
|
destroyer(*this, Address(element, elementAlign), elementType);
|
|
|
|
if (useEHCleanup)
|
|
PopCleanupBlock();
|
|
|
|
// Check whether we've reached the end.
|
|
llvm::Value *done = Builder.CreateICmpEQ(element, begin, "arraydestroy.done");
|
|
Builder.CreateCondBr(done, doneBB, bodyBB);
|
|
elementPast->addIncoming(element, Builder.GetInsertBlock());
|
|
|
|
// Done.
|
|
EmitBlock(doneBB);
|
|
}
|
|
|
|
/// Perform partial array destruction as if in an EH cleanup. Unlike
|
|
/// emitArrayDestroy, the element type here may still be an array type.
|
|
static void emitPartialArrayDestroy(CodeGenFunction &CGF,
|
|
llvm::Value *begin, llvm::Value *end,
|
|
QualType type, CharUnits elementAlign,
|
|
CodeGenFunction::Destroyer *destroyer) {
|
|
// If the element type is itself an array, drill down.
|
|
unsigned arrayDepth = 0;
|
|
while (const ArrayType *arrayType = CGF.getContext().getAsArrayType(type)) {
|
|
// VLAs don't require a GEP index to walk into.
|
|
if (!isa<VariableArrayType>(arrayType))
|
|
arrayDepth++;
|
|
type = arrayType->getElementType();
|
|
}
|
|
|
|
if (arrayDepth) {
|
|
llvm::Value *zero = llvm::ConstantInt::get(CGF.SizeTy, 0);
|
|
|
|
SmallVector<llvm::Value*,4> gepIndices(arrayDepth+1, zero);
|
|
begin = CGF.Builder.CreateInBoundsGEP(begin, gepIndices, "pad.arraybegin");
|
|
end = CGF.Builder.CreateInBoundsGEP(end, gepIndices, "pad.arrayend");
|
|
}
|
|
|
|
// Destroy the array. We don't ever need an EH cleanup because we
|
|
// assume that we're in an EH cleanup ourselves, so a throwing
|
|
// destructor causes an immediate terminate.
|
|
CGF.emitArrayDestroy(begin, end, type, elementAlign, destroyer,
|
|
/*checkZeroLength*/ true, /*useEHCleanup*/ false);
|
|
}
|
|
|
|
namespace {
|
|
/// RegularPartialArrayDestroy - a cleanup which performs a partial
|
|
/// array destroy where the end pointer is regularly determined and
|
|
/// does not need to be loaded from a local.
|
|
class RegularPartialArrayDestroy final : public EHScopeStack::Cleanup {
|
|
llvm::Value *ArrayBegin;
|
|
llvm::Value *ArrayEnd;
|
|
QualType ElementType;
|
|
CodeGenFunction::Destroyer *Destroyer;
|
|
CharUnits ElementAlign;
|
|
public:
|
|
RegularPartialArrayDestroy(llvm::Value *arrayBegin, llvm::Value *arrayEnd,
|
|
QualType elementType, CharUnits elementAlign,
|
|
CodeGenFunction::Destroyer *destroyer)
|
|
: ArrayBegin(arrayBegin), ArrayEnd(arrayEnd),
|
|
ElementType(elementType), Destroyer(destroyer),
|
|
ElementAlign(elementAlign) {}
|
|
|
|
void Emit(CodeGenFunction &CGF, Flags flags) override {
|
|
emitPartialArrayDestroy(CGF, ArrayBegin, ArrayEnd,
|
|
ElementType, ElementAlign, Destroyer);
|
|
}
|
|
};
|
|
|
|
/// IrregularPartialArrayDestroy - a cleanup which performs a
|
|
/// partial array destroy where the end pointer is irregularly
|
|
/// determined and must be loaded from a local.
|
|
class IrregularPartialArrayDestroy final : public EHScopeStack::Cleanup {
|
|
llvm::Value *ArrayBegin;
|
|
Address ArrayEndPointer;
|
|
QualType ElementType;
|
|
CodeGenFunction::Destroyer *Destroyer;
|
|
CharUnits ElementAlign;
|
|
public:
|
|
IrregularPartialArrayDestroy(llvm::Value *arrayBegin,
|
|
Address arrayEndPointer,
|
|
QualType elementType,
|
|
CharUnits elementAlign,
|
|
CodeGenFunction::Destroyer *destroyer)
|
|
: ArrayBegin(arrayBegin), ArrayEndPointer(arrayEndPointer),
|
|
ElementType(elementType), Destroyer(destroyer),
|
|
ElementAlign(elementAlign) {}
|
|
|
|
void Emit(CodeGenFunction &CGF, Flags flags) override {
|
|
llvm::Value *arrayEnd = CGF.Builder.CreateLoad(ArrayEndPointer);
|
|
emitPartialArrayDestroy(CGF, ArrayBegin, arrayEnd,
|
|
ElementType, ElementAlign, Destroyer);
|
|
}
|
|
};
|
|
} // end anonymous namespace
|
|
|
|
/// pushIrregularPartialArrayCleanup - Push an EH cleanup to destroy
|
|
/// already-constructed elements of the given array. The cleanup
|
|
/// may be popped with DeactivateCleanupBlock or PopCleanupBlock.
|
|
///
|
|
/// \param elementType - the immediate element type of the array;
|
|
/// possibly still an array type
|
|
void CodeGenFunction::pushIrregularPartialArrayCleanup(llvm::Value *arrayBegin,
|
|
Address arrayEndPointer,
|
|
QualType elementType,
|
|
CharUnits elementAlign,
|
|
Destroyer *destroyer) {
|
|
pushFullExprCleanup<IrregularPartialArrayDestroy>(EHCleanup,
|
|
arrayBegin, arrayEndPointer,
|
|
elementType, elementAlign,
|
|
destroyer);
|
|
}
|
|
|
|
/// pushRegularPartialArrayCleanup - Push an EH cleanup to destroy
|
|
/// already-constructed elements of the given array. The cleanup
|
|
/// may be popped with DeactivateCleanupBlock or PopCleanupBlock.
|
|
///
|
|
/// \param elementType - the immediate element type of the array;
|
|
/// possibly still an array type
|
|
void CodeGenFunction::pushRegularPartialArrayCleanup(llvm::Value *arrayBegin,
|
|
llvm::Value *arrayEnd,
|
|
QualType elementType,
|
|
CharUnits elementAlign,
|
|
Destroyer *destroyer) {
|
|
pushFullExprCleanup<RegularPartialArrayDestroy>(EHCleanup,
|
|
arrayBegin, arrayEnd,
|
|
elementType, elementAlign,
|
|
destroyer);
|
|
}
|
|
|
|
/// Lazily declare the @llvm.lifetime.start intrinsic.
|
|
llvm::Constant *CodeGenModule::getLLVMLifetimeStartFn() {
|
|
if (LifetimeStartFn)
|
|
return LifetimeStartFn;
|
|
LifetimeStartFn = llvm::Intrinsic::getDeclaration(&getModule(),
|
|
llvm::Intrinsic::lifetime_start, AllocaInt8PtrTy);
|
|
return LifetimeStartFn;
|
|
}
|
|
|
|
/// Lazily declare the @llvm.lifetime.end intrinsic.
|
|
llvm::Constant *CodeGenModule::getLLVMLifetimeEndFn() {
|
|
if (LifetimeEndFn)
|
|
return LifetimeEndFn;
|
|
LifetimeEndFn = llvm::Intrinsic::getDeclaration(&getModule(),
|
|
llvm::Intrinsic::lifetime_end, AllocaInt8PtrTy);
|
|
return LifetimeEndFn;
|
|
}
|
|
|
|
namespace {
|
|
/// A cleanup to perform a release of an object at the end of a
|
|
/// function. This is used to balance out the incoming +1 of a
|
|
/// ns_consumed argument when we can't reasonably do that just by
|
|
/// not doing the initial retain for a __block argument.
|
|
struct ConsumeARCParameter final : EHScopeStack::Cleanup {
|
|
ConsumeARCParameter(llvm::Value *param,
|
|
ARCPreciseLifetime_t precise)
|
|
: Param(param), Precise(precise) {}
|
|
|
|
llvm::Value *Param;
|
|
ARCPreciseLifetime_t Precise;
|
|
|
|
void Emit(CodeGenFunction &CGF, Flags flags) override {
|
|
CGF.EmitARCRelease(Param, Precise);
|
|
}
|
|
};
|
|
} // end anonymous namespace
|
|
|
|
/// Emit an alloca (or GlobalValue depending on target)
|
|
/// for the specified parameter and set up LocalDeclMap.
|
|
void CodeGenFunction::EmitParmDecl(const VarDecl &D, ParamValue Arg,
|
|
unsigned ArgNo) {
|
|
// FIXME: Why isn't ImplicitParamDecl a ParmVarDecl?
|
|
assert((isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D)) &&
|
|
"Invalid argument to EmitParmDecl");
|
|
|
|
Arg.getAnyValue()->setName(D.getName());
|
|
|
|
QualType Ty = D.getType();
|
|
|
|
// Use better IR generation for certain implicit parameters.
|
|
if (auto IPD = dyn_cast<ImplicitParamDecl>(&D)) {
|
|
// The only implicit argument a block has is its literal.
|
|
// We assume this is always passed directly.
|
|
if (BlockInfo) {
|
|
setBlockContextParameter(IPD, ArgNo, Arg.getDirectValue());
|
|
return;
|
|
}
|
|
}
|
|
|
|
Address DeclPtr = Address::invalid();
|
|
bool DoStore = false;
|
|
bool IsScalar = hasScalarEvaluationKind(Ty);
|
|
// If we already have a pointer to the argument, reuse the input pointer.
|
|
if (Arg.isIndirect()) {
|
|
DeclPtr = Arg.getIndirectAddress();
|
|
// If we have a prettier pointer type at this point, bitcast to that.
|
|
unsigned AS = DeclPtr.getType()->getAddressSpace();
|
|
llvm::Type *IRTy = ConvertTypeForMem(Ty)->getPointerTo(AS);
|
|
if (DeclPtr.getType() != IRTy)
|
|
DeclPtr = Builder.CreateBitCast(DeclPtr, IRTy, D.getName());
|
|
|
|
// Push a destructor cleanup for this parameter if the ABI requires it.
|
|
// Don't push a cleanup in a thunk for a method that will also emit a
|
|
// cleanup.
|
|
if (!IsScalar && !CurFuncIsThunk &&
|
|
getTarget().getCXXABI().areArgsDestroyedLeftToRightInCallee()) {
|
|
const CXXRecordDecl *RD = Ty->getAsCXXRecordDecl();
|
|
if (RD && RD->hasNonTrivialDestructor())
|
|
pushDestroy(QualType::DK_cxx_destructor, DeclPtr, Ty);
|
|
}
|
|
} else {
|
|
// Otherwise, create a temporary to hold the value.
|
|
DeclPtr = CreateMemTemp(Ty, getContext().getDeclAlign(&D),
|
|
D.getName() + ".addr");
|
|
DoStore = true;
|
|
}
|
|
|
|
llvm::Value *ArgVal = (DoStore ? Arg.getDirectValue() : nullptr);
|
|
|
|
LValue lv = MakeAddrLValue(DeclPtr, Ty);
|
|
if (IsScalar) {
|
|
Qualifiers qs = Ty.getQualifiers();
|
|
if (Qualifiers::ObjCLifetime lt = qs.getObjCLifetime()) {
|
|
// We honor __attribute__((ns_consumed)) for types with lifetime.
|
|
// For __strong, it's handled by just skipping the initial retain;
|
|
// otherwise we have to balance out the initial +1 with an extra
|
|
// cleanup to do the release at the end of the function.
|
|
bool isConsumed = D.hasAttr<NSConsumedAttr>();
|
|
|
|
// 'self' is always formally __strong, but if this is not an
|
|
// init method then we don't want to retain it.
|
|
if (D.isARCPseudoStrong()) {
|
|
const ObjCMethodDecl *method = cast<ObjCMethodDecl>(CurCodeDecl);
|
|
assert(&D == method->getSelfDecl());
|
|
assert(lt == Qualifiers::OCL_Strong);
|
|
assert(qs.hasConst());
|
|
assert(method->getMethodFamily() != OMF_init);
|
|
(void) method;
|
|
lt = Qualifiers::OCL_ExplicitNone;
|
|
}
|
|
|
|
// Load objects passed indirectly.
|
|
if (Arg.isIndirect() && !ArgVal)
|
|
ArgVal = Builder.CreateLoad(DeclPtr);
|
|
|
|
if (lt == Qualifiers::OCL_Strong) {
|
|
if (!isConsumed) {
|
|
if (CGM.getCodeGenOpts().OptimizationLevel == 0) {
|
|
// use objc_storeStrong(&dest, value) for retaining the
|
|
// object. But first, store a null into 'dest' because
|
|
// objc_storeStrong attempts to release its old value.
|
|
llvm::Value *Null = CGM.EmitNullConstant(D.getType());
|
|
EmitStoreOfScalar(Null, lv, /* isInitialization */ true);
|
|
EmitARCStoreStrongCall(lv.getAddress(), ArgVal, true);
|
|
DoStore = false;
|
|
}
|
|
else
|
|
// Don't use objc_retainBlock for block pointers, because we
|
|
// don't want to Block_copy something just because we got it
|
|
// as a parameter.
|
|
ArgVal = EmitARCRetainNonBlock(ArgVal);
|
|
}
|
|
} else {
|
|
// Push the cleanup for a consumed parameter.
|
|
if (isConsumed) {
|
|
ARCPreciseLifetime_t precise = (D.hasAttr<ObjCPreciseLifetimeAttr>()
|
|
? ARCPreciseLifetime : ARCImpreciseLifetime);
|
|
EHStack.pushCleanup<ConsumeARCParameter>(getARCCleanupKind(), ArgVal,
|
|
precise);
|
|
}
|
|
|
|
if (lt == Qualifiers::OCL_Weak) {
|
|
EmitARCInitWeak(DeclPtr, ArgVal);
|
|
DoStore = false; // The weak init is a store, no need to do two.
|
|
}
|
|
}
|
|
|
|
// Enter the cleanup scope.
|
|
EmitAutoVarWithLifetime(*this, D, DeclPtr, lt);
|
|
}
|
|
}
|
|
|
|
// Store the initial value into the alloca.
|
|
if (DoStore)
|
|
EmitStoreOfScalar(ArgVal, lv, /* isInitialization */ true);
|
|
|
|
setAddrOfLocalVar(&D, DeclPtr);
|
|
|
|
// Emit debug info for param declaration.
|
|
if (CGDebugInfo *DI = getDebugInfo()) {
|
|
if (CGM.getCodeGenOpts().getDebugInfo() >=
|
|
codegenoptions::LimitedDebugInfo) {
|
|
DI->EmitDeclareOfArgVariable(&D, DeclPtr.getPointer(), ArgNo, Builder);
|
|
}
|
|
}
|
|
|
|
if (D.hasAttr<AnnotateAttr>())
|
|
EmitVarAnnotations(&D, DeclPtr.getPointer());
|
|
|
|
// We can only check return value nullability if all arguments to the
|
|
// function satisfy their nullability preconditions. This makes it necessary
|
|
// to emit null checks for args in the function body itself.
|
|
if (requiresReturnValueNullabilityCheck()) {
|
|
auto Nullability = Ty->getNullability(getContext());
|
|
if (Nullability && *Nullability == NullabilityKind::NonNull) {
|
|
SanitizerScope SanScope(this);
|
|
RetValNullabilityPrecondition =
|
|
Builder.CreateAnd(RetValNullabilityPrecondition,
|
|
Builder.CreateIsNotNull(Arg.getAnyValue()));
|
|
}
|
|
}
|
|
}
|
|
|
|
void CodeGenModule::EmitOMPDeclareReduction(const OMPDeclareReductionDecl *D,
|
|
CodeGenFunction *CGF) {
|
|
if (!LangOpts.OpenMP || (!LangOpts.EmitAllDecls && !D->isUsed()))
|
|
return;
|
|
getOpenMPRuntime().emitUserDefinedReduction(CGF, D);
|
|
}
|