#include "CodeGenFunction.h"
#include "CGCXXABI.h"
#include "CGObjCRuntime.h"
#include "CGOpenMPRuntime.h"
#include "clang/Frontend/CodeGenOptions.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/IR/Intrinsics.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() && "VarDecl must have global 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, true);
return;
case TEK_Aggregate:
CGF.EmitAggExpr(Init, AggValueSlot::forLValue(lv,AggValueSlot::IsDestructed,
AggValueSlot::DoesNotNeedGCBarriers,
AggValueSlot::IsNotAliased));
return;
}
llvm_unreachable("bad evaluation kind");
}
static void EmitDeclDestroy(CodeGenFunction &CGF, const VarDecl &D,
ConstantAddress addr) {
CodeGenModule &CGM = CGF.CGM;
QualType type = D.getType();
QualType::DestructionKind dtorKind = type.isDestructedType();
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:
assert(!D.getTLSKind() && "should have rejected this");
return;
}
llvm::Constant *function;
llvm::Constant *argument;
const CXXRecordDecl *record = nullptr;
if (dtorKind == QualType::DK_cxx_destructor &&
(record = type->getAsCXXRecordDecl())) {
assert(!record->hasTrivialDestructor());
CXXDestructorDecl *dtor = record->getDestructor();
function = CGM.getAddrOfCXXStructor(dtor, StructorType::Complete);
argument = llvm::ConstantExpr::getBitCast(
addr.getPointer(), CGF.getTypes().ConvertType(type)->getPointerTo());
} else {
function = CodeGenFunction(CGM)
.generateDestroyHelper(addr, type, CGF.getDestroyer(dtorKind),
CGF.needsEHCleanup(dtorKind), &D);
argument = llvm::Constant::getNullValue(CGF.Int8PtrTy);
}
CGM.getCXXABI().registerGlobalDtor(CGF, D, function, argument);
}
static void EmitDeclInvariant(CodeGenFunction &CGF, const VarDecl &D,
llvm::Constant *Addr) {
if (!CGF.CGM.getCodeGenOpts().OptimizationLevel)
return;
llvm::Intrinsic::ID InvStartID = llvm::Intrinsic::invariant_start;
llvm::Constant *InvariantStart = CGF.CGM.getIntrinsic(InvStartID);
CharUnits WidthChars = CGF.getContext().getTypeSizeInChars(D.getType());
uint64_t Width = WidthChars.getQuantity();
llvm::Value *Args[2] = { llvm::ConstantInt::getSigned(CGF.Int64Ty, Width),
llvm::ConstantExpr::getBitCast(Addr, CGF.Int8PtrTy)};
CGF.Builder.CreateCall(InvariantStart, Args);
}
void CodeGenFunction::EmitCXXGlobalVarDeclInit(const VarDecl &D,
llvm::Constant *DeclPtr,
bool PerformInit) {
const Expr *Init = D.getInit();
QualType T = D.getType();
unsigned ExpectedAddrSpace = getContext().getTargetAddressSpace(T);
unsigned ActualAddrSpace = DeclPtr->getType()->getPointerAddressSpace();
if (ActualAddrSpace != ExpectedAddrSpace) {
llvm::Type *LTy = CGM.getTypes().ConvertTypeForMem(T);
llvm::PointerType *PTy = llvm::PointerType::get(LTy, ExpectedAddrSpace);
DeclPtr = llvm::ConstantExpr::getAddrSpaceCast(DeclPtr, PTy);
}
ConstantAddress DeclAddr(DeclPtr, getContext().getDeclAlign(&D));
if (!T->isReferenceType()) {
if (getLangOpts().OpenMP && D.hasAttr<OMPThreadPrivateDeclAttr>())
(void)CGM.getOpenMPRuntime().emitThreadPrivateVarDefinition(
&D, DeclAddr, D.getAttr<OMPThreadPrivateDeclAttr>()->getLocation(),
PerformInit, this);
if (PerformInit)
EmitDeclInit(*this, D, DeclAddr);
if (CGM.isTypeConstant(D.getType(), true))
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);
}
llvm::Constant *CodeGenFunction::createAtExitStub(const VarDecl &VD,
llvm::Constant *dtor,
llvm::Constant *addr) {
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.CreateGlobalInitOrDestructFunction(ty, FnName.str(),
FI,
VD.getLocation());
CodeGenFunction CGF(CGM);
CGF.StartFunction(&VD, CGM.getContext().VoidTy, fn, FI, FunctionArgList());
llvm::CallInst *call = CGF.Builder.CreateCall(dtor, addr);
if (llvm::Function *dtorFn =
dyn_cast<llvm::Function>(dtor->stripPointerCasts()))
call->setCallingConv(dtorFn->getCallingConv());
CGF.FinishFunction();
return fn;
}
void CodeGenFunction::registerGlobalDtorWithAtExit(const VarDecl &VD,
llvm::Constant *dtor,
llvm::Constant *addr) {
llvm::Constant *dtorStub = createAtExitStub(VD, dtor, addr);
llvm::FunctionType *atexitTy =
llvm::FunctionType::get(IntTy, dtorStub->getType(), false);
llvm::Constant *atexit =
CGM.CreateRuntimeFunction(atexitTy, "atexit");
if (llvm::Function *atexitFn = dyn_cast<llvm::Function>(atexit))
atexitFn->setDoesNotThrow();
EmitNounwindRuntimeCall(atexit, dtorStub);
}
void CodeGenFunction::EmitCXXGuardedInit(const VarDecl &D,
llvm::GlobalVariable *DeclPtr,
bool PerformInit) {
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);
}
llvm::Function *CodeGenModule::CreateGlobalInitOrDestructFunction(
llvm::FunctionType *FTy, const Twine &Name, const CGFunctionInfo &FI,
SourceLocation Loc, bool TLS) {
llvm::Function *Fn =
llvm::Function::Create(FTy, llvm::GlobalValue::InternalLinkage,
Name, &getModule());
if (!getLangOpts().AppleKext && !TLS) {
if (const char *Section = getTarget().getStaticInitSectionSpecifier())
Fn->setSection(Section);
}
SetInternalFunctionAttributes(nullptr, Fn, FI);
Fn->setCallingConv(getRuntimeCC());
if (!getLangOpts().Exceptions)
Fn->setDoesNotThrow();
if (!isInSanitizerBlacklist(Fn, Loc)) {
if (getLangOpts().Sanitize.hasOneOf(SanitizerKind::Address |
SanitizerKind::KernelAddress))
Fn->addFnAttr(llvm::Attribute::SanitizeAddress);
if (getLangOpts().Sanitize.has(SanitizerKind::Thread))
Fn->addFnAttr(llvm::Attribute::SanitizeThread);
if (getLangOpts().Sanitize.has(SanitizerKind::Memory))
Fn->addFnAttr(llvm::Attribute::SanitizeMemory);
if (getLangOpts().Sanitize.has(SanitizerKind::SafeStack))
Fn->addFnAttr(llvm::Attribute::SafeStack);
}
return Fn;
}
void CodeGenModule::EmitPointerToInitFunc(const VarDecl *D,
llvm::GlobalVariable *GV,
llvm::Function *InitFunc,
InitSegAttr *ISA) {
llvm::GlobalVariable *PtrArray = new llvm::GlobalVariable(
TheModule, InitFunc->getType(), true,
llvm::GlobalValue::PrivateLinkage, InitFunc, "__cxx_init_fn_ptr");
PtrArray->setSection(ISA->getSection());
addUsedGlobal(PtrArray);
if (llvm::Comdat *C = GV->getComdat())
PtrArray->setComdat(C);
}
void
CodeGenModule::EmitCXXGlobalVarDeclInitFunc(const VarDecl *D,
llvm::GlobalVariable *Addr,
bool PerformInit) {
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);
}
llvm::Function *Fn =
CreateGlobalInitOrDestructFunction(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()) {
CXXThreadLocalInits.push_back(Fn);
CXXThreadLocalInitVars.push_back(D);
} else if (PerformInit && ISA) {
EmitPointerToInitFunc(D, Addr, Fn, ISA);
} else if (auto *IPA = D->getAttr<InitPriorityAttr>()) {
OrderGlobalInits Key(IPA->getPriority(), PrioritizedCXXGlobalInits.size());
PrioritizedCXXGlobalInits.push_back(std::make_pair(Key, Fn));
} else if (isTemplateInstantiation(D->getTemplateSpecializationKind())) {
AddGlobalCtor(Fn, 65535, COMDATKey);
} else if (D->hasAttr<SelectAnyAttr>()) {
AddGlobalCtor(Fn, 65535, COMDATKey);
} else {
I = DelayedCXXInitPosition.find(D); 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;
}
}
DelayedCXXInitPosition[D] = ~0U;
}
void CodeGenModule::EmitCXXThreadLocalInitFunc() {
getCXXABI().EmitThreadLocalInitFuncs(
*this, CXXThreadLocals, CXXThreadLocalInits, CXXThreadLocalInitVars);
CXXThreadLocalInits.clear();
CXXThreadLocalInitVars.clear();
CXXThreadLocals.clear();
}
void
CodeGenModule::EmitCXXGlobalInitFunc() {
while (!CXXGlobalInits.empty() && !CXXGlobalInits.back())
CXXGlobalInits.pop_back();
if (CXXGlobalInits.empty() && PrioritizedCXXGlobalInits.empty())
return;
llvm::FunctionType *FTy = llvm::FunctionType::get(VoidTy, false);
const CGFunctionInfo &FI = getTypes().arrangeNullaryFunction();
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());
LocalCXXGlobalInits.clear();
unsigned Priority = I->first.priority;
std::string PrioritySuffix = llvm::utostr(Priority);
PrioritySuffix = std::string(6-PrioritySuffix.size(), '0')+PrioritySuffix;
llvm::Function *Fn = CreateGlobalInitOrDestructFunction(
FTy, "_GLOBAL__I_" + PrioritySuffix, FI);
for (; I < PrioE; ++I)
LocalCXXGlobalInits.push_back(I->second);
CodeGenFunction(*this).GenerateCXXGlobalInitFunc(Fn, LocalCXXGlobalInits);
AddGlobalCtor(Fn, Priority);
}
PrioritizedCXXGlobalInits.clear();
}
SmallString<128> FileName;
SourceManager &SM = Context.getSourceManager();
if (const FileEntry *MainFile = SM.getFileEntryForID(SM.getMainFileID())) {
FileName = llvm::sys::path::filename(MainFile->getName());
} else {
FileName = "<null>";
}
for (size_t i = 0; i < FileName.size(); ++i) {
if (!isPreprocessingNumberBody(FileName[i]))
FileName[i] = '_';
}
llvm::Function *Fn = CreateGlobalInitOrDestructFunction(
FTy, llvm::Twine("_GLOBAL__sub_I_", FileName), FI);
CodeGenFunction(*this).GenerateCXXGlobalInitFunc(Fn, CXXGlobalInits);
AddGlobalCtor(Fn);
CXXGlobalInits.clear();
}
void CodeGenModule::EmitCXXGlobalDtorFunc() {
if (CXXGlobalDtors.empty())
return;
llvm::FunctionType *FTy = llvm::FunctionType::get(VoidTy, false);
const CGFunctionInfo &FI = getTypes().arrangeNullaryFunction();
llvm::Function *Fn =
CreateGlobalInitOrDestructFunction(FTy, "_GLOBAL__D_a", FI);
CodeGenFunction(*this).GenerateCXXGlobalDtorsFunc(Fn, CXXGlobalDtors);
AddGlobalDtor(Fn);
}
void CodeGenFunction::GenerateCXXGlobalVarDeclInitFunc(llvm::Function *Fn,
const VarDecl *D,
llvm::GlobalVariable *Addr,
bool PerformInit) {
if (D->hasAttr<NoDebugAttr>())
DebugInfo = nullptr;
CurEHLocation = D->getLocStart();
StartFunction(GlobalDecl(D), getContext().VoidTy, Fn,
getTypes().arrangeNullaryFunction(),
FunctionArgList(), D->getLocation(),
D->getInit()->getExprLoc());
if (Addr->hasWeakLinkage() || Addr->hasLinkOnceLinkage()) {
EmitCXXGuardedInit(*D, Addr, PerformInit);
} else {
EmitCXXGlobalVarDeclInit(*D, Addr, PerformInit);
}
FinishFunction();
}
void
CodeGenFunction::GenerateCXXGlobalInitFunc(llvm::Function *Fn,
ArrayRef<llvm::Function *> Decls,
Address Guard) {
{
auto NL = ApplyDebugLocation::CreateEmpty(*this);
StartFunction(GlobalDecl(), getContext().VoidTy, Fn,
getTypes().arrangeNullaryFunction(), FunctionArgList());
auto AL = ApplyDebugLocation::CreateArtificial(*this);
llvm::BasicBlock *ExitBlock = nullptr;
if (Guard.isValid()) {
llvm::Value *GuardVal = Builder.CreateLoad(Guard);
llvm::Value *Uninit = Builder.CreateIsNull(GuardVal,
"guard.uninitialized");
llvm::BasicBlock *InitBlock = createBasicBlock("init");
ExitBlock = createBasicBlock("exit");
Builder.CreateCondBr(Uninit, InitBlock, ExitBlock);
EmitBlock(InitBlock);
Builder.CreateStore(llvm::ConstantInt::get(GuardVal->getType(),1), Guard);
}
RunCleanupsScope Scope(*this);
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::GenerateCXXGlobalDtorsFunc(llvm::Function *Fn,
const std::vector<std::pair<llvm::WeakVH, llvm::Constant*> >
&DtorsAndObjects) {
{
auto NL = ApplyDebugLocation::CreateEmpty(*this);
StartFunction(GlobalDecl(), getContext().VoidTy, Fn,
getTypes().arrangeNullaryFunction(), FunctionArgList());
auto AL = ApplyDebugLocation::CreateArtificial(*this);
for (unsigned i = 0, e = DtorsAndObjects.size(); i != e; ++i) {
llvm::Value *Callee = DtorsAndObjects[e - i - 1].first;
llvm::CallInst *CI = Builder.CreateCall(Callee,
DtorsAndObjects[e - i - 1].second);
if (llvm::Function *F = dyn_cast<llvm::Function>(Callee))
CI->setCallingConv(F->getCallingConv());
}
}
FinishFunction();
}
llvm::Function *CodeGenFunction::generateDestroyHelper(
Address addr, QualType type, Destroyer *destroyer,
bool useEHCleanupForArray, const VarDecl *VD) {
FunctionArgList args;
ImplicitParamDecl dst(getContext(), nullptr, SourceLocation(), nullptr,
getContext().VoidPtrTy);
args.push_back(&dst);
const CGFunctionInfo &FI =
CGM.getTypes().arrangeBuiltinFunctionDeclaration(getContext().VoidTy, args);
llvm::FunctionType *FTy = CGM.getTypes().GetFunctionType(FI);
llvm::Function *fn = CGM.CreateGlobalInitOrDestructFunction(
FTy, "__cxx_global_array_dtor", FI, VD->getLocation());
CurEHLocation = VD->getLocStart();
StartFunction(VD, getContext().VoidTy, fn, FI, args);
emitDestroy(addr, type, destroyer, useEHCleanupForArray);
FinishFunction();
return fn;
}