forked from OSchip/llvm-project
304 lines
10 KiB
C++
304 lines
10 KiB
C++
//===--- CGDeclCXX.cpp - Emit LLVM Code for C++ declarations --------------===//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file is distributed under the University of Illinois Open Source
|
|
// License. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
// This contains code dealing with code generation of C++ declarations
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#include "CodeGenFunction.h"
|
|
using namespace clang;
|
|
using namespace CodeGen;
|
|
|
|
static void EmitDeclInit(CodeGenFunction &CGF, const VarDecl &D,
|
|
llvm::Constant *DeclPtr) {
|
|
assert(D.hasGlobalStorage() && "VarDecl must have global storage!");
|
|
assert(!D.getType()->isReferenceType() &&
|
|
"Should not call EmitDeclInit on a reference!");
|
|
|
|
CodeGenModule &CGM = CGF.CGM;
|
|
ASTContext &Context = CGF.getContext();
|
|
|
|
const Expr *Init = D.getInit();
|
|
QualType T = D.getType();
|
|
bool isVolatile = Context.getCanonicalType(T).isVolatileQualified();
|
|
|
|
if (!CGF.hasAggregateLLVMType(T)) {
|
|
llvm::Value *V = CGF.EmitScalarExpr(Init);
|
|
CGF.EmitStoreOfScalar(V, DeclPtr, isVolatile, T);
|
|
} else if (T->isAnyComplexType()) {
|
|
CGF.EmitComplexExprIntoAddr(Init, DeclPtr, isVolatile);
|
|
} else {
|
|
CGF.EmitAggExpr(Init, DeclPtr, isVolatile);
|
|
|
|
// Avoid generating destructor(s) for initialized objects.
|
|
if (!isa<CXXConstructExpr>(Init))
|
|
return;
|
|
|
|
const ConstantArrayType *Array = Context.getAsConstantArrayType(T);
|
|
if (Array)
|
|
T = Context.getBaseElementType(Array);
|
|
|
|
const RecordType *RT = T->getAs<RecordType>();
|
|
if (!RT)
|
|
return;
|
|
|
|
CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
|
|
if (RD->hasTrivialDestructor())
|
|
return;
|
|
|
|
CXXDestructorDecl *Dtor = RD->getDestructor(Context);
|
|
|
|
llvm::Constant *DtorFn;
|
|
if (Array) {
|
|
DtorFn =
|
|
CodeGenFunction(CGM).GenerateCXXAggrDestructorHelper(Dtor,
|
|
Array,
|
|
DeclPtr);
|
|
const llvm::Type *Int8PtrTy =
|
|
llvm::Type::getInt8PtrTy(CGM.getLLVMContext());
|
|
DeclPtr = llvm::Constant::getNullValue(Int8PtrTy);
|
|
} else
|
|
DtorFn = CGM.GetAddrOfCXXDestructor(Dtor, Dtor_Complete);
|
|
|
|
CGF.EmitCXXGlobalDtorRegistration(DtorFn, DeclPtr);
|
|
}
|
|
}
|
|
|
|
void CodeGenFunction::EmitCXXGlobalVarDeclInit(const VarDecl &D,
|
|
llvm::Constant *DeclPtr) {
|
|
|
|
const Expr *Init = D.getInit();
|
|
QualType T = D.getType();
|
|
|
|
if (!T->isReferenceType()) {
|
|
EmitDeclInit(*this, D, DeclPtr);
|
|
return;
|
|
}
|
|
if (Init->isLvalue(getContext()) == Expr::LV_Valid) {
|
|
RValue RV = EmitReferenceBindingToExpr(Init, /*IsInitializer=*/true);
|
|
EmitStoreOfScalar(RV.getScalarVal(), DeclPtr, false, T);
|
|
return;
|
|
}
|
|
ErrorUnsupported(Init,
|
|
"global variable that binds reference to a non-lvalue");
|
|
}
|
|
|
|
void
|
|
CodeGenFunction::EmitCXXGlobalDtorRegistration(llvm::Constant *DtorFn,
|
|
llvm::Constant *DeclPtr) {
|
|
const llvm::Type *Int8PtrTy =
|
|
llvm::Type::getInt8Ty(VMContext)->getPointerTo();
|
|
|
|
std::vector<const llvm::Type *> Params;
|
|
Params.push_back(Int8PtrTy);
|
|
|
|
// Get the destructor function type
|
|
const llvm::Type *DtorFnTy =
|
|
llvm::FunctionType::get(llvm::Type::getVoidTy(VMContext), Params, false);
|
|
DtorFnTy = llvm::PointerType::getUnqual(DtorFnTy);
|
|
|
|
Params.clear();
|
|
Params.push_back(DtorFnTy);
|
|
Params.push_back(Int8PtrTy);
|
|
Params.push_back(Int8PtrTy);
|
|
|
|
// Get the __cxa_atexit function type
|
|
// extern "C" int __cxa_atexit ( void (*f)(void *), void *p, void *d );
|
|
const llvm::FunctionType *AtExitFnTy =
|
|
llvm::FunctionType::get(ConvertType(getContext().IntTy), Params, false);
|
|
|
|
llvm::Constant *AtExitFn = CGM.CreateRuntimeFunction(AtExitFnTy,
|
|
"__cxa_atexit");
|
|
|
|
llvm::Constant *Handle = CGM.CreateRuntimeVariable(Int8PtrTy,
|
|
"__dso_handle");
|
|
llvm::Value *Args[3] = { llvm::ConstantExpr::getBitCast(DtorFn, DtorFnTy),
|
|
llvm::ConstantExpr::getBitCast(DeclPtr, Int8PtrTy),
|
|
llvm::ConstantExpr::getBitCast(Handle, Int8PtrTy) };
|
|
Builder.CreateCall(AtExitFn, &Args[0], llvm::array_endof(Args));
|
|
}
|
|
|
|
void
|
|
CodeGenModule::EmitCXXGlobalVarDeclInitFunc(const VarDecl *D) {
|
|
const llvm::FunctionType *FTy
|
|
= llvm::FunctionType::get(llvm::Type::getVoidTy(VMContext),
|
|
false);
|
|
|
|
// Create a variable initialization function.
|
|
llvm::Function *Fn =
|
|
llvm::Function::Create(FTy, llvm::GlobalValue::InternalLinkage,
|
|
"__cxx_global_var_init", &TheModule);
|
|
|
|
CodeGenFunction(*this).GenerateCXXGlobalVarDeclInitFunc(Fn, D);
|
|
|
|
CXXGlobalInits.push_back(Fn);
|
|
}
|
|
|
|
void
|
|
CodeGenModule::EmitCXXGlobalInitFunc() {
|
|
if (CXXGlobalInits.empty())
|
|
return;
|
|
|
|
const llvm::FunctionType *FTy
|
|
= llvm::FunctionType::get(llvm::Type::getVoidTy(VMContext),
|
|
false);
|
|
|
|
// Create our global initialization function.
|
|
// FIXME: Should this be tweakable by targets?
|
|
llvm::Function *Fn =
|
|
llvm::Function::Create(FTy, llvm::GlobalValue::InternalLinkage,
|
|
"__cxx_global_initialization", &TheModule);
|
|
|
|
CodeGenFunction(*this).GenerateCXXGlobalInitFunc(Fn,
|
|
&CXXGlobalInits[0],
|
|
CXXGlobalInits.size());
|
|
AddGlobalCtor(Fn);
|
|
}
|
|
|
|
void CodeGenFunction::GenerateCXXGlobalVarDeclInitFunc(llvm::Function *Fn,
|
|
const VarDecl *D) {
|
|
StartFunction(GlobalDecl(), getContext().VoidTy, Fn, FunctionArgList(),
|
|
SourceLocation());
|
|
|
|
llvm::Constant *DeclPtr = CGM.GetAddrOfGlobalVar(D);
|
|
EmitCXXGlobalVarDeclInit(*D, DeclPtr);
|
|
|
|
FinishFunction();
|
|
}
|
|
|
|
void CodeGenFunction::GenerateCXXGlobalInitFunc(llvm::Function *Fn,
|
|
llvm::Constant **Decls,
|
|
unsigned NumDecls) {
|
|
StartFunction(GlobalDecl(), getContext().VoidTy, Fn, FunctionArgList(),
|
|
SourceLocation());
|
|
|
|
for (unsigned i = 0; i != NumDecls; ++i)
|
|
Builder.CreateCall(Decls[i]);
|
|
|
|
FinishFunction();
|
|
}
|
|
|
|
static llvm::Constant *getGuardAcquireFn(CodeGenFunction &CGF) {
|
|
// int __cxa_guard_acquire(__int64_t *guard_object);
|
|
|
|
const llvm::Type *Int64PtrTy =
|
|
llvm::Type::getInt64PtrTy(CGF.getLLVMContext());
|
|
|
|
std::vector<const llvm::Type*> Args(1, Int64PtrTy);
|
|
|
|
const llvm::FunctionType *FTy =
|
|
llvm::FunctionType::get(CGF.ConvertType(CGF.getContext().IntTy),
|
|
Args, /*isVarArg=*/false);
|
|
|
|
return CGF.CGM.CreateRuntimeFunction(FTy, "__cxa_guard_acquire");
|
|
}
|
|
|
|
static llvm::Constant *getGuardReleaseFn(CodeGenFunction &CGF) {
|
|
// void __cxa_guard_release(__int64_t *guard_object);
|
|
|
|
const llvm::Type *Int64PtrTy =
|
|
llvm::Type::getInt64PtrTy(CGF.getLLVMContext());
|
|
|
|
std::vector<const llvm::Type*> Args(1, Int64PtrTy);
|
|
|
|
const llvm::FunctionType *FTy =
|
|
llvm::FunctionType::get(llvm::Type::getVoidTy(CGF.getLLVMContext()),
|
|
Args, /*isVarArg=*/false);
|
|
|
|
return CGF.CGM.CreateRuntimeFunction(FTy, "__cxa_guard_release");
|
|
}
|
|
|
|
static llvm::Constant *getGuardAbortFn(CodeGenFunction &CGF) {
|
|
// void __cxa_guard_abort(__int64_t *guard_object);
|
|
|
|
const llvm::Type *Int64PtrTy =
|
|
llvm::Type::getInt64PtrTy(CGF.getLLVMContext());
|
|
|
|
std::vector<const llvm::Type*> Args(1, Int64PtrTy);
|
|
|
|
const llvm::FunctionType *FTy =
|
|
llvm::FunctionType::get(llvm::Type::getVoidTy(CGF.getLLVMContext()),
|
|
Args, /*isVarArg=*/false);
|
|
|
|
return CGF.CGM.CreateRuntimeFunction(FTy, "__cxa_guard_abort");
|
|
}
|
|
|
|
void
|
|
CodeGenFunction::EmitStaticCXXBlockVarDeclInit(const VarDecl &D,
|
|
llvm::GlobalVariable *GV) {
|
|
bool ThreadsafeStatics = getContext().getLangOptions().ThreadsafeStatics;
|
|
|
|
llvm::SmallString<256> GuardVName;
|
|
CGM.getMangleContext().mangleGuardVariable(&D, GuardVName);
|
|
|
|
// Create the guard variable.
|
|
const llvm::Type *Int64Ty = llvm::Type::getInt64Ty(VMContext);
|
|
llvm::GlobalValue *GuardVariable =
|
|
new llvm::GlobalVariable(CGM.getModule(), Int64Ty,
|
|
false, GV->getLinkage(),
|
|
llvm::Constant::getNullValue(Int64Ty),
|
|
GuardVName.str());
|
|
|
|
// Load the first byte of the guard variable.
|
|
const llvm::Type *PtrTy
|
|
= llvm::PointerType::get(llvm::Type::getInt8Ty(VMContext), 0);
|
|
llvm::Value *V =
|
|
Builder.CreateLoad(Builder.CreateBitCast(GuardVariable, PtrTy), "tmp");
|
|
|
|
llvm::BasicBlock *InitCheckBlock = createBasicBlock("init.check");
|
|
llvm::BasicBlock *EndBlock = createBasicBlock("init.end");
|
|
|
|
// Check if the first byte of the guard variable is zero.
|
|
Builder.CreateCondBr(Builder.CreateIsNull(V, "tobool"),
|
|
InitCheckBlock, EndBlock);
|
|
|
|
EmitBlock(InitCheckBlock);
|
|
|
|
if (ThreadsafeStatics) {
|
|
// Call __cxa_guard_acquire.
|
|
V = Builder.CreateCall(getGuardAcquireFn(*this), GuardVariable);
|
|
|
|
llvm::BasicBlock *InitBlock = createBasicBlock("init");
|
|
|
|
Builder.CreateCondBr(Builder.CreateIsNotNull(V, "tobool"),
|
|
InitBlock, EndBlock);
|
|
|
|
EmitBlock(InitBlock);
|
|
|
|
if (Exceptions) {
|
|
EHCleanupBlock Cleanup(*this);
|
|
|
|
// Call __cxa_guard_abort.
|
|
Builder.CreateCall(getGuardAbortFn(*this), GuardVariable);
|
|
}
|
|
}
|
|
|
|
if (D.getType()->isReferenceType()) {
|
|
QualType T = D.getType();
|
|
// We don't want to pass true for IsInitializer here, because a static
|
|
// reference to a temporary does not extend its lifetime.
|
|
RValue RV = EmitReferenceBindingToExpr(D.getInit(),
|
|
/*IsInitializer=*/false);
|
|
EmitStoreOfScalar(RV.getScalarVal(), GV, /*Volatile=*/false, T);
|
|
|
|
} else
|
|
EmitDeclInit(*this, D, GV);
|
|
|
|
if (ThreadsafeStatics) {
|
|
// Call __cxa_guard_release.
|
|
Builder.CreateCall(getGuardReleaseFn(*this), GuardVariable);
|
|
} else {
|
|
llvm::Value *One =
|
|
llvm::ConstantInt::get(llvm::Type::getInt8Ty(VMContext), 1);
|
|
Builder.CreateStore(One, Builder.CreateBitCast(GuardVariable, PtrTy));
|
|
}
|
|
|
|
EmitBlock(EndBlock);
|
|
}
|