summaryrefslogtreecommitdiffstats
path: root/contrib/llvm/tools/clang/lib/CodeGen/CGDeclCXX.cpp
diff options
context:
space:
mode:
Diffstat (limited to 'contrib/llvm/tools/clang/lib/CodeGen/CGDeclCXX.cpp')
-rw-r--r--contrib/llvm/tools/clang/lib/CodeGen/CGDeclCXX.cpp427
1 files changed, 427 insertions, 0 deletions
diff --git a/contrib/llvm/tools/clang/lib/CodeGen/CGDeclCXX.cpp b/contrib/llvm/tools/clang/lib/CodeGen/CGDeclCXX.cpp
new file mode 100644
index 0000000..ec3f386
--- /dev/null
+++ b/contrib/llvm/tools/clang/lib/CodeGen/CGDeclCXX.cpp
@@ -0,0 +1,427 @@
+//===--- 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"
+#include "clang/Frontend/CodeGenOptions.h"
+#include "llvm/Intrinsics.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!");
+
+ 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);
+ }
+}
+
+static void EmitDeclDestroy(CodeGenFunction &CGF, const VarDecl &D,
+ llvm::Constant *DeclPtr) {
+ CodeGenModule &CGM = CGF.CGM;
+ ASTContext &Context = CGF.getContext();
+
+ const Expr *Init = D.getInit();
+ QualType T = D.getType();
+ if (!CGF.hasAggregateLLVMType(T) || T->isAnyComplexType())
+ return;
+
+ // 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();
+
+ 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);
+ EmitDeclDestroy(*this, D, DeclPtr);
+ return;
+ }
+
+ RValue RV = EmitReferenceBindingToExpr(Init, &D);
+ EmitStoreOfScalar(RV.getScalarVal(), DeclPtr, false, T);
+}
+
+void
+CodeGenFunction::EmitCXXGlobalDtorRegistration(llvm::Constant *DtorFn,
+ llvm::Constant *DeclPtr) {
+ // Generate a global destructor entry if not using __cxa_atexit.
+ if (!CGM.getCodeGenOpts().CXAAtExit) {
+ CGM.AddCXXDtorEntry(DtorFn, DeclPtr);
+ return;
+ }
+
+ 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));
+}
+
+static llvm::Function *
+CreateGlobalInitOrDestructFunction(CodeGenModule &CGM,
+ const llvm::FunctionType *FTy,
+ llvm::StringRef Name) {
+ llvm::Function *Fn =
+ llvm::Function::Create(FTy, llvm::GlobalValue::InternalLinkage,
+ Name, &CGM.getModule());
+
+ // Set the section if needed.
+ if (const char *Section =
+ CGM.getContext().Target.getStaticInitSectionSpecifier())
+ Fn->setSection(Section);
+
+ if (!CGM.getLangOptions().Exceptions)
+ Fn->setDoesNotThrow();
+
+ return Fn;
+}
+
+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 =
+ CreateGlobalInitOrDestructFunction(*this, FTy, "__cxx_global_var_init");
+
+ CodeGenFunction(*this).GenerateCXXGlobalVarDeclInitFunc(Fn, D);
+
+ if (D->hasAttr<InitPriorityAttr>()) {
+ unsigned int order = D->getAttr<InitPriorityAttr>()->getPriority();
+ OrderGlobalInits Key(order, PrioritizedCXXGlobalInits.size());
+ PrioritizedCXXGlobalInits.push_back(std::make_pair(Key, Fn));
+ }
+ else
+ CXXGlobalInits.push_back(Fn);
+}
+
+void
+CodeGenModule::EmitCXXGlobalInitFunc() {
+ if (CXXGlobalInits.empty() && PrioritizedCXXGlobalInits.empty())
+ return;
+
+ const llvm::FunctionType *FTy
+ = llvm::FunctionType::get(llvm::Type::getVoidTy(VMContext),
+ false);
+
+ // Create our global initialization function.
+ llvm::Function *Fn =
+ CreateGlobalInitOrDestructFunction(*this, FTy, "_GLOBAL__I_a");
+
+ if (!PrioritizedCXXGlobalInits.empty()) {
+ llvm::SmallVector<llvm::Constant*, 8> LocalCXXGlobalInits;
+ llvm::array_pod_sort(PrioritizedCXXGlobalInits.begin(),
+ PrioritizedCXXGlobalInits.end());
+ for (unsigned i = 0; i < PrioritizedCXXGlobalInits.size(); i++) {
+ llvm::Function *Fn = PrioritizedCXXGlobalInits[i].second;
+ LocalCXXGlobalInits.push_back(Fn);
+ }
+ for (unsigned i = 0; i < CXXGlobalInits.size(); i++)
+ LocalCXXGlobalInits.push_back(CXXGlobalInits[i]);
+ CodeGenFunction(*this).GenerateCXXGlobalInitFunc(Fn,
+ &LocalCXXGlobalInits[0],
+ LocalCXXGlobalInits.size());
+ }
+ else
+ CodeGenFunction(*this).GenerateCXXGlobalInitFunc(Fn,
+ &CXXGlobalInits[0],
+ CXXGlobalInits.size());
+ AddGlobalCtor(Fn);
+}
+
+void CodeGenModule::EmitCXXGlobalDtorFunc() {
+ if (CXXGlobalDtors.empty())
+ return;
+
+ const llvm::FunctionType *FTy
+ = llvm::FunctionType::get(llvm::Type::getVoidTy(VMContext),
+ false);
+
+ // Create our global destructor function.
+ llvm::Function *Fn =
+ CreateGlobalInitOrDestructFunction(*this, FTy, "_GLOBAL__D_a");
+
+ CodeGenFunction(*this).GenerateCXXGlobalDtorFunc(Fn, CXXGlobalDtors);
+ AddGlobalDtor(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();
+}
+
+void CodeGenFunction::GenerateCXXGlobalDtorFunc(llvm::Function *Fn,
+ const std::vector<std::pair<llvm::WeakVH, llvm::Constant*> >
+ &DtorsAndObjects) {
+ StartFunction(GlobalDecl(), getContext().VoidTy, Fn, FunctionArgList(),
+ SourceLocation());
+
+ // Emit the dtors, in reverse order from construction.
+ 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);
+ // Make sure the call and the callee agree on calling convention.
+ if (llvm::Function *F = dyn_cast<llvm::Function>(Callee))
+ CI->setCallingConv(F->getCallingConv());
+ }
+
+ FinishFunction();
+}
+
+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) {
+ // Bail out early if this initializer isn't reachable.
+ if (!Builder.GetInsertBlock()) return;
+
+ bool ThreadsafeStatics = getContext().getLangOptions().ThreadsafeStatics;
+
+ llvm::SmallString<256> GuardVName;
+ CGM.getMangleContext().mangleGuardVariable(&D, GuardVName);
+
+ // Create the guard variable.
+ 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);
+
+ // Variables used when coping with thread-safe statics and exceptions.
+ 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);
+
+ // Call __cxa_guard_abort along the exceptional edge.
+ if (Exceptions) {
+ CleanupBlock Cleanup(*this, EHCleanup);
+ Builder.CreateCall(getGuardAbortFn(*this), GuardVariable);
+ }
+
+ EmitBlock(InitBlock);
+ }
+
+ if (D.getType()->isReferenceType()) {
+ QualType T = D.getType();
+ RValue RV = EmitReferenceBindingToExpr(D.getInit(), &D);
+ EmitStoreOfScalar(RV.getScalarVal(), GV, /*Volatile=*/false, T);
+
+ } else
+ EmitDeclInit(*this, D, GV);
+
+ if (ThreadsafeStatics) {
+ // Call __cxa_guard_release. This cannot throw.
+ Builder.CreateCall(getGuardReleaseFn(*this), GuardVariable);
+ } else {
+ llvm::Value *One =
+ llvm::ConstantInt::get(llvm::Type::getInt8Ty(VMContext), 1);
+ Builder.CreateStore(One, Builder.CreateBitCast(GuardVariable, PtrTy));
+ }
+
+ // Register the call to the destructor.
+ if (!D.getType()->isReferenceType())
+ EmitDeclDestroy(*this, D, GV);
+
+ EmitBlock(EndBlock);
+}
+
+/// GenerateCXXAggrDestructorHelper - Generates a helper function which when
+/// invoked, calls the default destructor on array elements in reverse order of
+/// construction.
+llvm::Function *
+CodeGenFunction::GenerateCXXAggrDestructorHelper(const CXXDestructorDecl *D,
+ const ArrayType *Array,
+ llvm::Value *This) {
+ FunctionArgList Args;
+ ImplicitParamDecl *Dst =
+ ImplicitParamDecl::Create(getContext(), 0,
+ SourceLocation(), 0,
+ getContext().getPointerType(getContext().VoidTy));
+ Args.push_back(std::make_pair(Dst, Dst->getType()));
+
+ const CGFunctionInfo &FI =
+ CGM.getTypes().getFunctionInfo(getContext().VoidTy, Args,
+ FunctionType::ExtInfo());
+ const llvm::FunctionType *FTy = CGM.getTypes().GetFunctionType(FI, false);
+ llvm::Function *Fn =
+ CreateGlobalInitOrDestructFunction(CGM, FTy, "__cxx_global_array_dtor");
+
+ StartFunction(GlobalDecl(), getContext().VoidTy, Fn, Args, SourceLocation());
+
+ QualType BaseElementTy = getContext().getBaseElementType(Array);
+ const llvm::Type *BasePtr = ConvertType(BaseElementTy)->getPointerTo();
+ llvm::Value *BaseAddrPtr = Builder.CreateBitCast(This, BasePtr);
+
+ EmitCXXAggrDestructorCall(D, Array, BaseAddrPtr);
+
+ FinishFunction();
+
+ return Fn;
+}
OpenPOWER on IntegriCloud