llvm-project/clang/lib/CodeGen/CGClass.cpp

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//===--- CGClass.cpp - Emit LLVM Code for C++ classes ---------------------===//
//
// 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 C++ code generation of classes
//
//===----------------------------------------------------------------------===//
#include "CGBlocks.h"
#include "CGCXXABI.h"
#include "CGDebugInfo.h"
#include "CGRecordLayout.h"
#include "CodeGenFunction.h"
#include "clang/AST/CXXInheritance.h"
Implement conversion to function pointer for generic lambdas without captures. The general strategy is to create template versions of the conversion function and static invoker and then during template argument deduction of the conversion function, create the corresponding call-operator and static invoker specializations, and when the conversion function is marked referenced generate the body of the conversion function using the corresponding static-invoker specialization. Similarly, Codegen does something similar - when asked to emit the IR for a specialized static invoker of a generic lambda, it forwards emission to the corresponding call operator. This patch has been reviewed in person both by Doug and Richard. Richard gave me the LGTM. A few minor changes: - per Richard's request i added a simple check to gracefully inform that captures (init, explicit or default) have not been added to generic lambdas just yet (instead of the assertion violation). - I removed a few lines of code that added the call operators instantiated parameters to the currentinstantiationscope. Not only did it not handle parameter packs, but it is more relevant in the patch for nested lambdas which will follow this one, and fix that problem more comprehensively. - Doug had commented that the original implementation strategy of using the TypeSourceInfo of the call operator to create the static-invoker was flawed and allowed const as a member qualifier to creep into the type of the static-invoker. I currently kludge around it - but after my initial discussion with Doug, with a follow up session with Richard, I have added a FIXME so that a more elegant solution that involves the use of TrivialTypeSourceInfo call followed by the correct wiring of the template parameters to the functionprototypeloc is forthcoming. Thanks! llvm-svn: 191634
2013-09-29 16:45:24 +08:00
#include "clang/AST/DeclTemplate.h"
#include "clang/AST/EvaluatedExprVisitor.h"
#include "clang/AST/RecordLayout.h"
#include "clang/AST/StmtCXX.h"
#include "clang/Basic/TargetBuiltins.h"
#include "clang/CodeGen/CGFunctionInfo.h"
#include "clang/Frontend/CodeGenOptions.h"
using namespace clang;
using namespace CodeGen;
static CharUnits
ComputeNonVirtualBaseClassOffset(ASTContext &Context,
const CXXRecordDecl *DerivedClass,
CastExpr::path_const_iterator Start,
CastExpr::path_const_iterator End) {
CharUnits Offset = CharUnits::Zero();
const CXXRecordDecl *RD = DerivedClass;
for (CastExpr::path_const_iterator I = Start; I != End; ++I) {
const CXXBaseSpecifier *Base = *I;
assert(!Base->isVirtual() && "Should not see virtual bases here!");
// Get the layout.
const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
const CXXRecordDecl *BaseDecl =
cast<CXXRecordDecl>(Base->getType()->getAs<RecordType>()->getDecl());
// Add the offset.
Offset += Layout.getBaseClassOffset(BaseDecl);
RD = BaseDecl;
}
return Offset;
}
llvm::Constant *
CodeGenModule::GetNonVirtualBaseClassOffset(const CXXRecordDecl *ClassDecl,
CastExpr::path_const_iterator PathBegin,
CastExpr::path_const_iterator PathEnd) {
assert(PathBegin != PathEnd && "Base path should not be empty!");
CharUnits Offset =
ComputeNonVirtualBaseClassOffset(getContext(), ClassDecl,
PathBegin, PathEnd);
if (Offset.isZero())
return nullptr;
llvm::Type *PtrDiffTy =
Types.ConvertType(getContext().getPointerDiffType());
return llvm::ConstantInt::get(PtrDiffTy, Offset.getQuantity());
}
/// Gets the address of a direct base class within a complete object.
/// This should only be used for (1) non-virtual bases or (2) virtual bases
/// when the type is known to be complete (e.g. in complete destructors).
///
/// The object pointed to by 'This' is assumed to be non-null.
llvm::Value *
CodeGenFunction::GetAddressOfDirectBaseInCompleteClass(llvm::Value *This,
const CXXRecordDecl *Derived,
const CXXRecordDecl *Base,
bool BaseIsVirtual) {
// 'this' must be a pointer (in some address space) to Derived.
assert(This->getType()->isPointerTy() &&
cast<llvm::PointerType>(This->getType())->getElementType()
== ConvertType(Derived));
// Compute the offset of the virtual base.
CharUnits Offset;
const ASTRecordLayout &Layout = getContext().getASTRecordLayout(Derived);
if (BaseIsVirtual)
Offset = Layout.getVBaseClassOffset(Base);
else
Offset = Layout.getBaseClassOffset(Base);
// Shift and cast down to the base type.
// TODO: for complete types, this should be possible with a GEP.
llvm::Value *V = This;
if (Offset.isPositive()) {
V = Builder.CreateBitCast(V, Int8PtrTy);
V = Builder.CreateConstInBoundsGEP1_64(V, Offset.getQuantity());
}
V = Builder.CreateBitCast(V, ConvertType(Base)->getPointerTo());
return V;
}
static llvm::Value *
ApplyNonVirtualAndVirtualOffset(CodeGenFunction &CGF, llvm::Value *ptr,
CharUnits nonVirtualOffset,
llvm::Value *virtualOffset) {
// Assert that we have something to do.
assert(!nonVirtualOffset.isZero() || virtualOffset != nullptr);
// Compute the offset from the static and dynamic components.
llvm::Value *baseOffset;
if (!nonVirtualOffset.isZero()) {
baseOffset = llvm::ConstantInt::get(CGF.PtrDiffTy,
nonVirtualOffset.getQuantity());
if (virtualOffset) {
baseOffset = CGF.Builder.CreateAdd(virtualOffset, baseOffset);
}
} else {
baseOffset = virtualOffset;
}
// Apply the base offset.
ptr = CGF.Builder.CreateBitCast(ptr, CGF.Int8PtrTy);
ptr = CGF.Builder.CreateInBoundsGEP(ptr, baseOffset, "add.ptr");
return ptr;
}
llvm::Value *
CodeGenFunction::GetAddressOfBaseClass(llvm::Value *Value,
const CXXRecordDecl *Derived,
CastExpr::path_const_iterator PathBegin,
CastExpr::path_const_iterator PathEnd,
bool NullCheckValue) {
assert(PathBegin != PathEnd && "Base path should not be empty!");
CastExpr::path_const_iterator Start = PathBegin;
const CXXRecordDecl *VBase = nullptr;
// Sema has done some convenient canonicalization here: if the
// access path involved any virtual steps, the conversion path will
// *start* with a step down to the correct virtual base subobject,
// and hence will not require any further steps.
if ((*Start)->isVirtual()) {
VBase =
cast<CXXRecordDecl>((*Start)->getType()->getAs<RecordType>()->getDecl());
++Start;
}
// Compute the static offset of the ultimate destination within its
// allocating subobject (the virtual base, if there is one, or else
// the "complete" object that we see).
CharUnits NonVirtualOffset =
ComputeNonVirtualBaseClassOffset(getContext(), VBase ? VBase : Derived,
Start, PathEnd);
// If there's a virtual step, we can sometimes "devirtualize" it.
// For now, that's limited to when the derived type is final.
// TODO: "devirtualize" this for accesses to known-complete objects.
if (VBase && Derived->hasAttr<FinalAttr>()) {
const ASTRecordLayout &layout = getContext().getASTRecordLayout(Derived);
CharUnits vBaseOffset = layout.getVBaseClassOffset(VBase);
NonVirtualOffset += vBaseOffset;
VBase = nullptr; // we no longer have a virtual step
}
// Get the base pointer type.
llvm::Type *BasePtrTy =
ConvertType((PathEnd[-1])->getType())->getPointerTo();
// If the static offset is zero and we don't have a virtual step,
// just do a bitcast; null checks are unnecessary.
if (NonVirtualOffset.isZero() && !VBase) {
return Builder.CreateBitCast(Value, BasePtrTy);
}
llvm::BasicBlock *origBB = nullptr;
llvm::BasicBlock *endBB = nullptr;
// Skip over the offset (and the vtable load) if we're supposed to
// null-check the pointer.
if (NullCheckValue) {
origBB = Builder.GetInsertBlock();
llvm::BasicBlock *notNullBB = createBasicBlock("cast.notnull");
endBB = createBasicBlock("cast.end");
llvm::Value *isNull = Builder.CreateIsNull(Value);
Builder.CreateCondBr(isNull, endBB, notNullBB);
EmitBlock(notNullBB);
}
// Compute the virtual offset.
llvm::Value *VirtualOffset = nullptr;
if (VBase) {
VirtualOffset =
CGM.getCXXABI().GetVirtualBaseClassOffset(*this, Value, Derived, VBase);
}
// Apply both offsets.
Value = ApplyNonVirtualAndVirtualOffset(*this, Value,
NonVirtualOffset,
VirtualOffset);
// Cast to the destination type.
Value = Builder.CreateBitCast(Value, BasePtrTy);
// Build a phi if we needed a null check.
if (NullCheckValue) {
llvm::BasicBlock *notNullBB = Builder.GetInsertBlock();
Builder.CreateBr(endBB);
EmitBlock(endBB);
llvm::PHINode *PHI = Builder.CreatePHI(BasePtrTy, 2, "cast.result");
PHI->addIncoming(Value, notNullBB);
PHI->addIncoming(llvm::Constant::getNullValue(BasePtrTy), origBB);
Value = PHI;
}
return Value;
}
llvm::Value *
CodeGenFunction::GetAddressOfDerivedClass(llvm::Value *Value,
const CXXRecordDecl *Derived,
CastExpr::path_const_iterator PathBegin,
CastExpr::path_const_iterator PathEnd,
bool NullCheckValue) {
assert(PathBegin != PathEnd && "Base path should not be empty!");
QualType DerivedTy =
getContext().getCanonicalType(getContext().getTagDeclType(Derived));
llvm::Type *DerivedPtrTy = ConvertType(DerivedTy)->getPointerTo();
llvm::Value *NonVirtualOffset =
CGM.GetNonVirtualBaseClassOffset(Derived, PathBegin, PathEnd);
if (!NonVirtualOffset) {
// No offset, we can just cast back.
return Builder.CreateBitCast(Value, DerivedPtrTy);
}
llvm::BasicBlock *CastNull = nullptr;
llvm::BasicBlock *CastNotNull = nullptr;
llvm::BasicBlock *CastEnd = nullptr;
if (NullCheckValue) {
CastNull = createBasicBlock("cast.null");
CastNotNull = createBasicBlock("cast.notnull");
CastEnd = createBasicBlock("cast.end");
llvm::Value *IsNull = Builder.CreateIsNull(Value);
Builder.CreateCondBr(IsNull, CastNull, CastNotNull);
EmitBlock(CastNotNull);
}
// Apply the offset.
Value = Builder.CreateBitCast(Value, Int8PtrTy);
Value = Builder.CreateGEP(Value, Builder.CreateNeg(NonVirtualOffset),
"sub.ptr");
// Just cast.
Value = Builder.CreateBitCast(Value, DerivedPtrTy);
if (NullCheckValue) {
Builder.CreateBr(CastEnd);
EmitBlock(CastNull);
Builder.CreateBr(CastEnd);
EmitBlock(CastEnd);
llvm::PHINode *PHI = Builder.CreatePHI(Value->getType(), 2);
PHI->addIncoming(Value, CastNotNull);
PHI->addIncoming(llvm::Constant::getNullValue(Value->getType()),
CastNull);
Value = PHI;
}
return Value;
}
llvm::Value *CodeGenFunction::GetVTTParameter(GlobalDecl GD,
bool ForVirtualBase,
bool Delegating) {
if (!CGM.getCXXABI().NeedsVTTParameter(GD)) {
// This constructor/destructor does not need a VTT parameter.
return nullptr;
}
const CXXRecordDecl *RD = cast<CXXMethodDecl>(CurCodeDecl)->getParent();
const CXXRecordDecl *Base = cast<CXXMethodDecl>(GD.getDecl())->getParent();
llvm::Value *VTT;
uint64_t SubVTTIndex;
if (Delegating) {
// If this is a delegating constructor call, just load the VTT.
return LoadCXXVTT();
} else if (RD == Base) {
// If the record matches the base, this is the complete ctor/dtor
// variant calling the base variant in a class with virtual bases.
assert(!CGM.getCXXABI().NeedsVTTParameter(CurGD) &&
"doing no-op VTT offset in base dtor/ctor?");
assert(!ForVirtualBase && "Can't have same class as virtual base!");
SubVTTIndex = 0;
} else {
const ASTRecordLayout &Layout = getContext().getASTRecordLayout(RD);
CharUnits BaseOffset = ForVirtualBase ?
Layout.getVBaseClassOffset(Base) :
Layout.getBaseClassOffset(Base);
SubVTTIndex =
CGM.getVTables().getSubVTTIndex(RD, BaseSubobject(Base, BaseOffset));
assert(SubVTTIndex != 0 && "Sub-VTT index must be greater than zero!");
}
if (CGM.getCXXABI().NeedsVTTParameter(CurGD)) {
// A VTT parameter was passed to the constructor, use it.
VTT = LoadCXXVTT();
VTT = Builder.CreateConstInBoundsGEP1_64(VTT, SubVTTIndex);
} else {
// We're the complete constructor, so get the VTT by name.
VTT = CGM.getVTables().GetAddrOfVTT(RD);
VTT = Builder.CreateConstInBoundsGEP2_64(VTT, 0, SubVTTIndex);
}
return VTT;
}
namespace {
/// Call the destructor for a direct base class.
struct CallBaseDtor : EHScopeStack::Cleanup {
const CXXRecordDecl *BaseClass;
bool BaseIsVirtual;
CallBaseDtor(const CXXRecordDecl *Base, bool BaseIsVirtual)
: BaseClass(Base), BaseIsVirtual(BaseIsVirtual) {}
void Emit(CodeGenFunction &CGF, Flags flags) override {
const CXXRecordDecl *DerivedClass =
cast<CXXMethodDecl>(CGF.CurCodeDecl)->getParent();
const CXXDestructorDecl *D = BaseClass->getDestructor();
llvm::Value *Addr =
CGF.GetAddressOfDirectBaseInCompleteClass(CGF.LoadCXXThis(),
DerivedClass, BaseClass,
BaseIsVirtual);
CGF.EmitCXXDestructorCall(D, Dtor_Base, BaseIsVirtual,
/*Delegating=*/false, Addr);
}
};
/// A visitor which checks whether an initializer uses 'this' in a
/// way which requires the vtable to be properly set.
struct DynamicThisUseChecker : EvaluatedExprVisitor<DynamicThisUseChecker> {
typedef EvaluatedExprVisitor<DynamicThisUseChecker> super;
bool UsesThis;
DynamicThisUseChecker(ASTContext &C) : super(C), UsesThis(false) {}
// Black-list all explicit and implicit references to 'this'.
//
// Do we need to worry about external references to 'this' derived
// from arbitrary code? If so, then anything which runs arbitrary
// external code might potentially access the vtable.
void VisitCXXThisExpr(CXXThisExpr *E) { UsesThis = true; }
};
}
static bool BaseInitializerUsesThis(ASTContext &C, const Expr *Init) {
DynamicThisUseChecker Checker(C);
Checker.Visit(const_cast<Expr*>(Init));
return Checker.UsesThis;
}
static void EmitBaseInitializer(CodeGenFunction &CGF,
const CXXRecordDecl *ClassDecl,
CXXCtorInitializer *BaseInit,
CXXCtorType CtorType) {
assert(BaseInit->isBaseInitializer() &&
"Must have base initializer!");
llvm::Value *ThisPtr = CGF.LoadCXXThis();
const Type *BaseType = BaseInit->getBaseClass();
CXXRecordDecl *BaseClassDecl =
cast<CXXRecordDecl>(BaseType->getAs<RecordType>()->getDecl());
bool isBaseVirtual = BaseInit->isBaseVirtual();
// The base constructor doesn't construct virtual bases.
if (CtorType == Ctor_Base && isBaseVirtual)
return;
// If the initializer for the base (other than the constructor
// itself) accesses 'this' in any way, we need to initialize the
// vtables.
if (BaseInitializerUsesThis(CGF.getContext(), BaseInit->getInit()))
CGF.InitializeVTablePointers(ClassDecl);
// We can pretend to be a complete class because it only matters for
// virtual bases, and we only do virtual bases for complete ctors.
llvm::Value *V =
CGF.GetAddressOfDirectBaseInCompleteClass(ThisPtr, ClassDecl,
BaseClassDecl,
isBaseVirtual);
CharUnits Alignment = CGF.getContext().getTypeAlignInChars(BaseType);
AggValueSlot AggSlot =
AggValueSlot::forAddr(V, Alignment, Qualifiers(),
AggValueSlot::IsDestructed,
AggValueSlot::DoesNotNeedGCBarriers,
AggValueSlot::IsNotAliased);
CGF.EmitAggExpr(BaseInit->getInit(), AggSlot);
if (CGF.CGM.getLangOpts().Exceptions &&
!BaseClassDecl->hasTrivialDestructor())
CGF.EHStack.pushCleanup<CallBaseDtor>(EHCleanup, BaseClassDecl,
isBaseVirtual);
}
Reimplement code generation for copying fields in the implicitly-generated copy constructor. Previously, Sema would perform some checking and instantiation to determine which copy constructors, etc., would be called, then CodeGen would attempt to figure out which copy constructor to call... but would get it wrong, or poke at an uninstantiated default argument, or fail in other ways. The new scheme is similar to what we now do for the implicit copy-assignment operator, where Sema performs all of the semantic analysis and builds specific ASTs that look similar to the ASTs we'd get from explicitly writing the copy constructor, so that CodeGen need only do a direct translation. However, it's not quite that simple because one cannot explicit write elementwise copy-construction of an array. So, I've extended CXXBaseOrMemberInitializer to contain a list of indexing variables used to copy-construct the elements. For example, if we have: struct A { A(const A&); }; struct B { A array[2][3]; }; then we generate an implicit copy assignment operator for B that looks something like this: B::B(const B &other) : array[i0][i1](other.array[i0][i1]) { } CodeGen will loop over the invented variables i0 and i1 to visit all elements in the array, so that each element in the destination array will be copy-constructed from the corresponding element in the source array. Of course, if we're dealing with arrays of scalars or class types with trivial copy-assignment operators, we just generate a memcpy rather than a loop. Fixes PR6928, PR5989, and PR6887. Boost.Regex now compiles and passes all of its regression tests. Conspicuously missing from this patch is handling for the exceptional case, where we need to destruct those objects that we have constructed. I'll address that case separately. llvm-svn: 103079
2010-05-05 13:51:00 +08:00
static void EmitAggMemberInitializer(CodeGenFunction &CGF,
LValue LHS,
Expr *Init,
Reimplement code generation for copying fields in the implicitly-generated copy constructor. Previously, Sema would perform some checking and instantiation to determine which copy constructors, etc., would be called, then CodeGen would attempt to figure out which copy constructor to call... but would get it wrong, or poke at an uninstantiated default argument, or fail in other ways. The new scheme is similar to what we now do for the implicit copy-assignment operator, where Sema performs all of the semantic analysis and builds specific ASTs that look similar to the ASTs we'd get from explicitly writing the copy constructor, so that CodeGen need only do a direct translation. However, it's not quite that simple because one cannot explicit write elementwise copy-construction of an array. So, I've extended CXXBaseOrMemberInitializer to contain a list of indexing variables used to copy-construct the elements. For example, if we have: struct A { A(const A&); }; struct B { A array[2][3]; }; then we generate an implicit copy assignment operator for B that looks something like this: B::B(const B &other) : array[i0][i1](other.array[i0][i1]) { } CodeGen will loop over the invented variables i0 and i1 to visit all elements in the array, so that each element in the destination array will be copy-constructed from the corresponding element in the source array. Of course, if we're dealing with arrays of scalars or class types with trivial copy-assignment operators, we just generate a memcpy rather than a loop. Fixes PR6928, PR5989, and PR6887. Boost.Regex now compiles and passes all of its regression tests. Conspicuously missing from this patch is handling for the exceptional case, where we need to destruct those objects that we have constructed. I'll address that case separately. llvm-svn: 103079
2010-05-05 13:51:00 +08:00
llvm::Value *ArrayIndexVar,
QualType T,
ArrayRef<VarDecl *> ArrayIndexes,
Reimplement code generation for copying fields in the implicitly-generated copy constructor. Previously, Sema would perform some checking and instantiation to determine which copy constructors, etc., would be called, then CodeGen would attempt to figure out which copy constructor to call... but would get it wrong, or poke at an uninstantiated default argument, or fail in other ways. The new scheme is similar to what we now do for the implicit copy-assignment operator, where Sema performs all of the semantic analysis and builds specific ASTs that look similar to the ASTs we'd get from explicitly writing the copy constructor, so that CodeGen need only do a direct translation. However, it's not quite that simple because one cannot explicit write elementwise copy-construction of an array. So, I've extended CXXBaseOrMemberInitializer to contain a list of indexing variables used to copy-construct the elements. For example, if we have: struct A { A(const A&); }; struct B { A array[2][3]; }; then we generate an implicit copy assignment operator for B that looks something like this: B::B(const B &other) : array[i0][i1](other.array[i0][i1]) { } CodeGen will loop over the invented variables i0 and i1 to visit all elements in the array, so that each element in the destination array will be copy-constructed from the corresponding element in the source array. Of course, if we're dealing with arrays of scalars or class types with trivial copy-assignment operators, we just generate a memcpy rather than a loop. Fixes PR6928, PR5989, and PR6887. Boost.Regex now compiles and passes all of its regression tests. Conspicuously missing from this patch is handling for the exceptional case, where we need to destruct those objects that we have constructed. I'll address that case separately. llvm-svn: 103079
2010-05-05 13:51:00 +08:00
unsigned Index) {
if (Index == ArrayIndexes.size()) {
LValue LV = LHS;
if (ArrayIndexVar) {
// If we have an array index variable, load it and use it as an offset.
// Then, increment the value.
llvm::Value *Dest = LHS.getAddress();
llvm::Value *ArrayIndex = CGF.Builder.CreateLoad(ArrayIndexVar);
Dest = CGF.Builder.CreateInBoundsGEP(Dest, ArrayIndex, "destaddress");
llvm::Value *Next = llvm::ConstantInt::get(ArrayIndex->getType(), 1);
Next = CGF.Builder.CreateAdd(ArrayIndex, Next, "inc");
CGF.Builder.CreateStore(Next, ArrayIndexVar);
// Update the LValue.
LV.setAddress(Dest);
CharUnits Align = CGF.getContext().getTypeAlignInChars(T);
LV.setAlignment(std::min(Align, LV.getAlignment()));
Reimplement code generation for copying fields in the implicitly-generated copy constructor. Previously, Sema would perform some checking and instantiation to determine which copy constructors, etc., would be called, then CodeGen would attempt to figure out which copy constructor to call... but would get it wrong, or poke at an uninstantiated default argument, or fail in other ways. The new scheme is similar to what we now do for the implicit copy-assignment operator, where Sema performs all of the semantic analysis and builds specific ASTs that look similar to the ASTs we'd get from explicitly writing the copy constructor, so that CodeGen need only do a direct translation. However, it's not quite that simple because one cannot explicit write elementwise copy-construction of an array. So, I've extended CXXBaseOrMemberInitializer to contain a list of indexing variables used to copy-construct the elements. For example, if we have: struct A { A(const A&); }; struct B { A array[2][3]; }; then we generate an implicit copy assignment operator for B that looks something like this: B::B(const B &other) : array[i0][i1](other.array[i0][i1]) { } CodeGen will loop over the invented variables i0 and i1 to visit all elements in the array, so that each element in the destination array will be copy-constructed from the corresponding element in the source array. Of course, if we're dealing with arrays of scalars or class types with trivial copy-assignment operators, we just generate a memcpy rather than a loop. Fixes PR6928, PR5989, and PR6887. Boost.Regex now compiles and passes all of its regression tests. Conspicuously missing from this patch is handling for the exceptional case, where we need to destruct those objects that we have constructed. I'll address that case separately. llvm-svn: 103079
2010-05-05 13:51:00 +08:00
}
switch (CGF.getEvaluationKind(T)) {
case TEK_Scalar:
CGF.EmitScalarInit(Init, /*decl*/ nullptr, LV, false);
break;
case TEK_Complex:
CGF.EmitComplexExprIntoLValue(Init, LV, /*isInit*/ true);
break;
case TEK_Aggregate: {
AggValueSlot Slot =
AggValueSlot::forLValue(LV,
AggValueSlot::IsDestructed,
AggValueSlot::DoesNotNeedGCBarriers,
AggValueSlot::IsNotAliased);
CGF.EmitAggExpr(Init, Slot);
break;
}
}
Reimplement code generation for copying fields in the implicitly-generated copy constructor. Previously, Sema would perform some checking and instantiation to determine which copy constructors, etc., would be called, then CodeGen would attempt to figure out which copy constructor to call... but would get it wrong, or poke at an uninstantiated default argument, or fail in other ways. The new scheme is similar to what we now do for the implicit copy-assignment operator, where Sema performs all of the semantic analysis and builds specific ASTs that look similar to the ASTs we'd get from explicitly writing the copy constructor, so that CodeGen need only do a direct translation. However, it's not quite that simple because one cannot explicit write elementwise copy-construction of an array. So, I've extended CXXBaseOrMemberInitializer to contain a list of indexing variables used to copy-construct the elements. For example, if we have: struct A { A(const A&); }; struct B { A array[2][3]; }; then we generate an implicit copy assignment operator for B that looks something like this: B::B(const B &other) : array[i0][i1](other.array[i0][i1]) { } CodeGen will loop over the invented variables i0 and i1 to visit all elements in the array, so that each element in the destination array will be copy-constructed from the corresponding element in the source array. Of course, if we're dealing with arrays of scalars or class types with trivial copy-assignment operators, we just generate a memcpy rather than a loop. Fixes PR6928, PR5989, and PR6887. Boost.Regex now compiles and passes all of its regression tests. Conspicuously missing from this patch is handling for the exceptional case, where we need to destruct those objects that we have constructed. I'll address that case separately. llvm-svn: 103079
2010-05-05 13:51:00 +08:00
return;
}
Reimplement code generation for copying fields in the implicitly-generated copy constructor. Previously, Sema would perform some checking and instantiation to determine which copy constructors, etc., would be called, then CodeGen would attempt to figure out which copy constructor to call... but would get it wrong, or poke at an uninstantiated default argument, or fail in other ways. The new scheme is similar to what we now do for the implicit copy-assignment operator, where Sema performs all of the semantic analysis and builds specific ASTs that look similar to the ASTs we'd get from explicitly writing the copy constructor, so that CodeGen need only do a direct translation. However, it's not quite that simple because one cannot explicit write elementwise copy-construction of an array. So, I've extended CXXBaseOrMemberInitializer to contain a list of indexing variables used to copy-construct the elements. For example, if we have: struct A { A(const A&); }; struct B { A array[2][3]; }; then we generate an implicit copy assignment operator for B that looks something like this: B::B(const B &other) : array[i0][i1](other.array[i0][i1]) { } CodeGen will loop over the invented variables i0 and i1 to visit all elements in the array, so that each element in the destination array will be copy-constructed from the corresponding element in the source array. Of course, if we're dealing with arrays of scalars or class types with trivial copy-assignment operators, we just generate a memcpy rather than a loop. Fixes PR6928, PR5989, and PR6887. Boost.Regex now compiles and passes all of its regression tests. Conspicuously missing from this patch is handling for the exceptional case, where we need to destruct those objects that we have constructed. I'll address that case separately. llvm-svn: 103079
2010-05-05 13:51:00 +08:00
const ConstantArrayType *Array = CGF.getContext().getAsConstantArrayType(T);
assert(Array && "Array initialization without the array type?");
llvm::Value *IndexVar
= CGF.GetAddrOfLocalVar(ArrayIndexes[Index]);
Reimplement code generation for copying fields in the implicitly-generated copy constructor. Previously, Sema would perform some checking and instantiation to determine which copy constructors, etc., would be called, then CodeGen would attempt to figure out which copy constructor to call... but would get it wrong, or poke at an uninstantiated default argument, or fail in other ways. The new scheme is similar to what we now do for the implicit copy-assignment operator, where Sema performs all of the semantic analysis and builds specific ASTs that look similar to the ASTs we'd get from explicitly writing the copy constructor, so that CodeGen need only do a direct translation. However, it's not quite that simple because one cannot explicit write elementwise copy-construction of an array. So, I've extended CXXBaseOrMemberInitializer to contain a list of indexing variables used to copy-construct the elements. For example, if we have: struct A { A(const A&); }; struct B { A array[2][3]; }; then we generate an implicit copy assignment operator for B that looks something like this: B::B(const B &other) : array[i0][i1](other.array[i0][i1]) { } CodeGen will loop over the invented variables i0 and i1 to visit all elements in the array, so that each element in the destination array will be copy-constructed from the corresponding element in the source array. Of course, if we're dealing with arrays of scalars or class types with trivial copy-assignment operators, we just generate a memcpy rather than a loop. Fixes PR6928, PR5989, and PR6887. Boost.Regex now compiles and passes all of its regression tests. Conspicuously missing from this patch is handling for the exceptional case, where we need to destruct those objects that we have constructed. I'll address that case separately. llvm-svn: 103079
2010-05-05 13:51:00 +08:00
assert(IndexVar && "Array index variable not loaded");
// Initialize this index variable to zero.
llvm::Value* Zero
= llvm::Constant::getNullValue(
CGF.ConvertType(CGF.getContext().getSizeType()));
CGF.Builder.CreateStore(Zero, IndexVar);
// Start the loop with a block that tests the condition.
llvm::BasicBlock *CondBlock = CGF.createBasicBlock("for.cond");
llvm::BasicBlock *AfterFor = CGF.createBasicBlock("for.end");
CGF.EmitBlock(CondBlock);
llvm::BasicBlock *ForBody = CGF.createBasicBlock("for.body");
// Generate: if (loop-index < number-of-elements) fall to the loop body,
// otherwise, go to the block after the for-loop.
uint64_t NumElements = Array->getSize().getZExtValue();
llvm::Value *Counter = CGF.Builder.CreateLoad(IndexVar);
llvm::Value *NumElementsPtr =
llvm::ConstantInt::get(Counter->getType(), NumElements);
Reimplement code generation for copying fields in the implicitly-generated copy constructor. Previously, Sema would perform some checking and instantiation to determine which copy constructors, etc., would be called, then CodeGen would attempt to figure out which copy constructor to call... but would get it wrong, or poke at an uninstantiated default argument, or fail in other ways. The new scheme is similar to what we now do for the implicit copy-assignment operator, where Sema performs all of the semantic analysis and builds specific ASTs that look similar to the ASTs we'd get from explicitly writing the copy constructor, so that CodeGen need only do a direct translation. However, it's not quite that simple because one cannot explicit write elementwise copy-construction of an array. So, I've extended CXXBaseOrMemberInitializer to contain a list of indexing variables used to copy-construct the elements. For example, if we have: struct A { A(const A&); }; struct B { A array[2][3]; }; then we generate an implicit copy assignment operator for B that looks something like this: B::B(const B &other) : array[i0][i1](other.array[i0][i1]) { } CodeGen will loop over the invented variables i0 and i1 to visit all elements in the array, so that each element in the destination array will be copy-constructed from the corresponding element in the source array. Of course, if we're dealing with arrays of scalars or class types with trivial copy-assignment operators, we just generate a memcpy rather than a loop. Fixes PR6928, PR5989, and PR6887. Boost.Regex now compiles and passes all of its regression tests. Conspicuously missing from this patch is handling for the exceptional case, where we need to destruct those objects that we have constructed. I'll address that case separately. llvm-svn: 103079
2010-05-05 13:51:00 +08:00
llvm::Value *IsLess = CGF.Builder.CreateICmpULT(Counter, NumElementsPtr,
"isless");
// If the condition is true, execute the body.
CGF.Builder.CreateCondBr(IsLess, ForBody, AfterFor);
CGF.EmitBlock(ForBody);
llvm::BasicBlock *ContinueBlock = CGF.createBasicBlock("for.inc");
// Inside the loop body recurse to emit the inner loop or, eventually, the
// constructor call.
EmitAggMemberInitializer(CGF, LHS, Init, ArrayIndexVar,
Array->getElementType(), ArrayIndexes, Index + 1);
Reimplement code generation for copying fields in the implicitly-generated copy constructor. Previously, Sema would perform some checking and instantiation to determine which copy constructors, etc., would be called, then CodeGen would attempt to figure out which copy constructor to call... but would get it wrong, or poke at an uninstantiated default argument, or fail in other ways. The new scheme is similar to what we now do for the implicit copy-assignment operator, where Sema performs all of the semantic analysis and builds specific ASTs that look similar to the ASTs we'd get from explicitly writing the copy constructor, so that CodeGen need only do a direct translation. However, it's not quite that simple because one cannot explicit write elementwise copy-construction of an array. So, I've extended CXXBaseOrMemberInitializer to contain a list of indexing variables used to copy-construct the elements. For example, if we have: struct A { A(const A&); }; struct B { A array[2][3]; }; then we generate an implicit copy assignment operator for B that looks something like this: B::B(const B &other) : array[i0][i1](other.array[i0][i1]) { } CodeGen will loop over the invented variables i0 and i1 to visit all elements in the array, so that each element in the destination array will be copy-constructed from the corresponding element in the source array. Of course, if we're dealing with arrays of scalars or class types with trivial copy-assignment operators, we just generate a memcpy rather than a loop. Fixes PR6928, PR5989, and PR6887. Boost.Regex now compiles and passes all of its regression tests. Conspicuously missing from this patch is handling for the exceptional case, where we need to destruct those objects that we have constructed. I'll address that case separately. llvm-svn: 103079
2010-05-05 13:51:00 +08:00
CGF.EmitBlock(ContinueBlock);
// Emit the increment of the loop counter.
llvm::Value *NextVal = llvm::ConstantInt::get(Counter->getType(), 1);
Counter = CGF.Builder.CreateLoad(IndexVar);
NextVal = CGF.Builder.CreateAdd(Counter, NextVal, "inc");
CGF.Builder.CreateStore(NextVal, IndexVar);
// Finally, branch back up to the condition for the next iteration.
CGF.EmitBranch(CondBlock);
// Emit the fall-through block.
CGF.EmitBlock(AfterFor, true);
}
static void EmitMemberInitializer(CodeGenFunction &CGF,
const CXXRecordDecl *ClassDecl,
CXXCtorInitializer *MemberInit,
Reimplement code generation for copying fields in the implicitly-generated copy constructor. Previously, Sema would perform some checking and instantiation to determine which copy constructors, etc., would be called, then CodeGen would attempt to figure out which copy constructor to call... but would get it wrong, or poke at an uninstantiated default argument, or fail in other ways. The new scheme is similar to what we now do for the implicit copy-assignment operator, where Sema performs all of the semantic analysis and builds specific ASTs that look similar to the ASTs we'd get from explicitly writing the copy constructor, so that CodeGen need only do a direct translation. However, it's not quite that simple because one cannot explicit write elementwise copy-construction of an array. So, I've extended CXXBaseOrMemberInitializer to contain a list of indexing variables used to copy-construct the elements. For example, if we have: struct A { A(const A&); }; struct B { A array[2][3]; }; then we generate an implicit copy assignment operator for B that looks something like this: B::B(const B &other) : array[i0][i1](other.array[i0][i1]) { } CodeGen will loop over the invented variables i0 and i1 to visit all elements in the array, so that each element in the destination array will be copy-constructed from the corresponding element in the source array. Of course, if we're dealing with arrays of scalars or class types with trivial copy-assignment operators, we just generate a memcpy rather than a loop. Fixes PR6928, PR5989, and PR6887. Boost.Regex now compiles and passes all of its regression tests. Conspicuously missing from this patch is handling for the exceptional case, where we need to destruct those objects that we have constructed. I'll address that case separately. llvm-svn: 103079
2010-05-05 13:51:00 +08:00
const CXXConstructorDecl *Constructor,
FunctionArgList &Args) {
assert(MemberInit->isAnyMemberInitializer() &&
"Must have member initializer!");
assert(MemberInit->getInit() && "Must have initializer!");
// non-static data member initializers.
FieldDecl *Field = MemberInit->getAnyMember();
QualType FieldType = Field->getType();
llvm::Value *ThisPtr = CGF.LoadCXXThis();
QualType RecordTy = CGF.getContext().getTypeDeclType(ClassDecl);
LValue LHS = CGF.MakeNaturalAlignAddrLValue(ThisPtr, RecordTy);
if (MemberInit->isIndirectMemberInitializer()) {
// If we are initializing an anonymous union field, drill down to
// the field.
IndirectFieldDecl *IndirectField = MemberInit->getIndirectMember();
for (const auto *I : IndirectField->chain())
LHS = CGF.EmitLValueForFieldInitialization(LHS, cast<FieldDecl>(I));
FieldType = MemberInit->getIndirectMember()->getAnonField()->getType();
} else {
LHS = CGF.EmitLValueForFieldInitialization(LHS, Field);
}
// Special case: if we are in a copy or move constructor, and we are copying
// an array of PODs or classes with trivial copy constructors, ignore the
// AST and perform the copy we know is equivalent.
// FIXME: This is hacky at best... if we had a bit more explicit information
// in the AST, we could generalize it more easily.
const ConstantArrayType *Array
= CGF.getContext().getAsConstantArrayType(FieldType);
if (Array && Constructor->isDefaulted() &&
Constructor->isCopyOrMoveConstructor()) {
QualType BaseElementTy = CGF.getContext().getBaseElementType(Array);
CXXConstructExpr *CE = dyn_cast<CXXConstructExpr>(MemberInit->getInit());
if (BaseElementTy.isPODType(CGF.getContext()) ||
(CE && CE->getConstructor()->isTrivial())) {
// Find the source pointer. We know it's the last argument because
// we know we're in an implicit copy constructor.
unsigned SrcArgIndex = Args.size() - 1;
llvm::Value *SrcPtr
= CGF.Builder.CreateLoad(CGF.GetAddrOfLocalVar(Args[SrcArgIndex]));
LValue ThisRHSLV = CGF.MakeNaturalAlignAddrLValue(SrcPtr, RecordTy);
LValue Src = CGF.EmitLValueForFieldInitialization(ThisRHSLV, Field);
// Copy the aggregate.
CGF.EmitAggregateCopy(LHS.getAddress(), Src.getAddress(), FieldType,
LHS.isVolatileQualified());
return;
}
}
ArrayRef<VarDecl *> ArrayIndexes;
if (MemberInit->getNumArrayIndices())
ArrayIndexes = MemberInit->getArrayIndexes();
CGF.EmitInitializerForField(Field, LHS, MemberInit->getInit(), ArrayIndexes);
}
void CodeGenFunction::EmitInitializerForField(FieldDecl *Field,
LValue LHS, Expr *Init,
ArrayRef<VarDecl *> ArrayIndexes) {
QualType FieldType = Field->getType();
switch (getEvaluationKind(FieldType)) {
case TEK_Scalar:
if (LHS.isSimple()) {
EmitExprAsInit(Init, Field, LHS, false);
} else {
RValue RHS = RValue::get(EmitScalarExpr(Init));
EmitStoreThroughLValue(RHS, LHS);
}
break;
case TEK_Complex:
EmitComplexExprIntoLValue(Init, LHS, /*isInit*/ true);
break;
case TEK_Aggregate: {
llvm::Value *ArrayIndexVar = nullptr;
if (ArrayIndexes.size()) {
llvm::Type *SizeTy = ConvertType(getContext().getSizeType());
Reimplement code generation for copying fields in the implicitly-generated copy constructor. Previously, Sema would perform some checking and instantiation to determine which copy constructors, etc., would be called, then CodeGen would attempt to figure out which copy constructor to call... but would get it wrong, or poke at an uninstantiated default argument, or fail in other ways. The new scheme is similar to what we now do for the implicit copy-assignment operator, where Sema performs all of the semantic analysis and builds specific ASTs that look similar to the ASTs we'd get from explicitly writing the copy constructor, so that CodeGen need only do a direct translation. However, it's not quite that simple because one cannot explicit write elementwise copy-construction of an array. So, I've extended CXXBaseOrMemberInitializer to contain a list of indexing variables used to copy-construct the elements. For example, if we have: struct A { A(const A&); }; struct B { A array[2][3]; }; then we generate an implicit copy assignment operator for B that looks something like this: B::B(const B &other) : array[i0][i1](other.array[i0][i1]) { } CodeGen will loop over the invented variables i0 and i1 to visit all elements in the array, so that each element in the destination array will be copy-constructed from the corresponding element in the source array. Of course, if we're dealing with arrays of scalars or class types with trivial copy-assignment operators, we just generate a memcpy rather than a loop. Fixes PR6928, PR5989, and PR6887. Boost.Regex now compiles and passes all of its regression tests. Conspicuously missing from this patch is handling for the exceptional case, where we need to destruct those objects that we have constructed. I'll address that case separately. llvm-svn: 103079
2010-05-05 13:51:00 +08:00
// The LHS is a pointer to the first object we'll be constructing, as
// a flat array.
QualType BaseElementTy = getContext().getBaseElementType(FieldType);
llvm::Type *BasePtr = ConvertType(BaseElementTy);
Reimplement code generation for copying fields in the implicitly-generated copy constructor. Previously, Sema would perform some checking and instantiation to determine which copy constructors, etc., would be called, then CodeGen would attempt to figure out which copy constructor to call... but would get it wrong, or poke at an uninstantiated default argument, or fail in other ways. The new scheme is similar to what we now do for the implicit copy-assignment operator, where Sema performs all of the semantic analysis and builds specific ASTs that look similar to the ASTs we'd get from explicitly writing the copy constructor, so that CodeGen need only do a direct translation. However, it's not quite that simple because one cannot explicit write elementwise copy-construction of an array. So, I've extended CXXBaseOrMemberInitializer to contain a list of indexing variables used to copy-construct the elements. For example, if we have: struct A { A(const A&); }; struct B { A array[2][3]; }; then we generate an implicit copy assignment operator for B that looks something like this: B::B(const B &other) : array[i0][i1](other.array[i0][i1]) { } CodeGen will loop over the invented variables i0 and i1 to visit all elements in the array, so that each element in the destination array will be copy-constructed from the corresponding element in the source array. Of course, if we're dealing with arrays of scalars or class types with trivial copy-assignment operators, we just generate a memcpy rather than a loop. Fixes PR6928, PR5989, and PR6887. Boost.Regex now compiles and passes all of its regression tests. Conspicuously missing from this patch is handling for the exceptional case, where we need to destruct those objects that we have constructed. I'll address that case separately. llvm-svn: 103079
2010-05-05 13:51:00 +08:00
BasePtr = llvm::PointerType::getUnqual(BasePtr);
llvm::Value *BaseAddrPtr = Builder.CreateBitCast(LHS.getAddress(),
BasePtr);
LHS = MakeAddrLValue(BaseAddrPtr, BaseElementTy);
Reimplement code generation for copying fields in the implicitly-generated copy constructor. Previously, Sema would perform some checking and instantiation to determine which copy constructors, etc., would be called, then CodeGen would attempt to figure out which copy constructor to call... but would get it wrong, or poke at an uninstantiated default argument, or fail in other ways. The new scheme is similar to what we now do for the implicit copy-assignment operator, where Sema performs all of the semantic analysis and builds specific ASTs that look similar to the ASTs we'd get from explicitly writing the copy constructor, so that CodeGen need only do a direct translation. However, it's not quite that simple because one cannot explicit write elementwise copy-construction of an array. So, I've extended CXXBaseOrMemberInitializer to contain a list of indexing variables used to copy-construct the elements. For example, if we have: struct A { A(const A&); }; struct B { A array[2][3]; }; then we generate an implicit copy assignment operator for B that looks something like this: B::B(const B &other) : array[i0][i1](other.array[i0][i1]) { } CodeGen will loop over the invented variables i0 and i1 to visit all elements in the array, so that each element in the destination array will be copy-constructed from the corresponding element in the source array. Of course, if we're dealing with arrays of scalars or class types with trivial copy-assignment operators, we just generate a memcpy rather than a loop. Fixes PR6928, PR5989, and PR6887. Boost.Regex now compiles and passes all of its regression tests. Conspicuously missing from this patch is handling for the exceptional case, where we need to destruct those objects that we have constructed. I'll address that case separately. llvm-svn: 103079
2010-05-05 13:51:00 +08:00
// Create an array index that will be used to walk over all of the
// objects we're constructing.
ArrayIndexVar = CreateTempAlloca(SizeTy, "object.index");
Reimplement code generation for copying fields in the implicitly-generated copy constructor. Previously, Sema would perform some checking and instantiation to determine which copy constructors, etc., would be called, then CodeGen would attempt to figure out which copy constructor to call... but would get it wrong, or poke at an uninstantiated default argument, or fail in other ways. The new scheme is similar to what we now do for the implicit copy-assignment operator, where Sema performs all of the semantic analysis and builds specific ASTs that look similar to the ASTs we'd get from explicitly writing the copy constructor, so that CodeGen need only do a direct translation. However, it's not quite that simple because one cannot explicit write elementwise copy-construction of an array. So, I've extended CXXBaseOrMemberInitializer to contain a list of indexing variables used to copy-construct the elements. For example, if we have: struct A { A(const A&); }; struct B { A array[2][3]; }; then we generate an implicit copy assignment operator for B that looks something like this: B::B(const B &other) : array[i0][i1](other.array[i0][i1]) { } CodeGen will loop over the invented variables i0 and i1 to visit all elements in the array, so that each element in the destination array will be copy-constructed from the corresponding element in the source array. Of course, if we're dealing with arrays of scalars or class types with trivial copy-assignment operators, we just generate a memcpy rather than a loop. Fixes PR6928, PR5989, and PR6887. Boost.Regex now compiles and passes all of its regression tests. Conspicuously missing from this patch is handling for the exceptional case, where we need to destruct those objects that we have constructed. I'll address that case separately. llvm-svn: 103079
2010-05-05 13:51:00 +08:00
llvm::Value *Zero = llvm::Constant::getNullValue(SizeTy);
Builder.CreateStore(Zero, ArrayIndexVar);
Reimplement code generation for copying fields in the implicitly-generated copy constructor. Previously, Sema would perform some checking and instantiation to determine which copy constructors, etc., would be called, then CodeGen would attempt to figure out which copy constructor to call... but would get it wrong, or poke at an uninstantiated default argument, or fail in other ways. The new scheme is similar to what we now do for the implicit copy-assignment operator, where Sema performs all of the semantic analysis and builds specific ASTs that look similar to the ASTs we'd get from explicitly writing the copy constructor, so that CodeGen need only do a direct translation. However, it's not quite that simple because one cannot explicit write elementwise copy-construction of an array. So, I've extended CXXBaseOrMemberInitializer to contain a list of indexing variables used to copy-construct the elements. For example, if we have: struct A { A(const A&); }; struct B { A array[2][3]; }; then we generate an implicit copy assignment operator for B that looks something like this: B::B(const B &other) : array[i0][i1](other.array[i0][i1]) { } CodeGen will loop over the invented variables i0 and i1 to visit all elements in the array, so that each element in the destination array will be copy-constructed from the corresponding element in the source array. Of course, if we're dealing with arrays of scalars or class types with trivial copy-assignment operators, we just generate a memcpy rather than a loop. Fixes PR6928, PR5989, and PR6887. Boost.Regex now compiles and passes all of its regression tests. Conspicuously missing from this patch is handling for the exceptional case, where we need to destruct those objects that we have constructed. I'll address that case separately. llvm-svn: 103079
2010-05-05 13:51:00 +08:00
// Emit the block variables for the array indices, if any.
for (unsigned I = 0, N = ArrayIndexes.size(); I != N; ++I)
EmitAutoVarDecl(*ArrayIndexes[I]);
Reimplement code generation for copying fields in the implicitly-generated copy constructor. Previously, Sema would perform some checking and instantiation to determine which copy constructors, etc., would be called, then CodeGen would attempt to figure out which copy constructor to call... but would get it wrong, or poke at an uninstantiated default argument, or fail in other ways. The new scheme is similar to what we now do for the implicit copy-assignment operator, where Sema performs all of the semantic analysis and builds specific ASTs that look similar to the ASTs we'd get from explicitly writing the copy constructor, so that CodeGen need only do a direct translation. However, it's not quite that simple because one cannot explicit write elementwise copy-construction of an array. So, I've extended CXXBaseOrMemberInitializer to contain a list of indexing variables used to copy-construct the elements. For example, if we have: struct A { A(const A&); }; struct B { A array[2][3]; }; then we generate an implicit copy assignment operator for B that looks something like this: B::B(const B &other) : array[i0][i1](other.array[i0][i1]) { } CodeGen will loop over the invented variables i0 and i1 to visit all elements in the array, so that each element in the destination array will be copy-constructed from the corresponding element in the source array. Of course, if we're dealing with arrays of scalars or class types with trivial copy-assignment operators, we just generate a memcpy rather than a loop. Fixes PR6928, PR5989, and PR6887. Boost.Regex now compiles and passes all of its regression tests. Conspicuously missing from this patch is handling for the exceptional case, where we need to destruct those objects that we have constructed. I'll address that case separately. llvm-svn: 103079
2010-05-05 13:51:00 +08:00
}
EmitAggMemberInitializer(*this, LHS, Init, ArrayIndexVar, FieldType,
ArrayIndexes, 0);
}
}
// Ensure that we destroy this object if an exception is thrown
// later in the constructor.
QualType::DestructionKind dtorKind = FieldType.isDestructedType();
if (needsEHCleanup(dtorKind))
pushEHDestroy(dtorKind, LHS.getAddress(), FieldType);
}
/// Checks whether the given constructor is a valid subject for the
/// complete-to-base constructor delegation optimization, i.e.
/// emitting the complete constructor as a simple call to the base
/// constructor.
static bool IsConstructorDelegationValid(const CXXConstructorDecl *Ctor) {
// Currently we disable the optimization for classes with virtual
// bases because (1) the addresses of parameter variables need to be
// consistent across all initializers but (2) the delegate function
// call necessarily creates a second copy of the parameter variable.
//
// The limiting example (purely theoretical AFAIK):
// struct A { A(int &c) { c++; } };
// struct B : virtual A {
// B(int count) : A(count) { printf("%d\n", count); }
// };
// ...although even this example could in principle be emitted as a
// delegation since the address of the parameter doesn't escape.
if (Ctor->getParent()->getNumVBases()) {
// TODO: white-list trivial vbase initializers. This case wouldn't
// be subject to the restrictions below.
// TODO: white-list cases where:
// - there are no non-reference parameters to the constructor
// - the initializers don't access any non-reference parameters
// - the initializers don't take the address of non-reference
// parameters
// - etc.
// If we ever add any of the above cases, remember that:
// - function-try-blocks will always blacklist this optimization
// - we need to perform the constructor prologue and cleanup in
// EmitConstructorBody.
return false;
}
// We also disable the optimization for variadic functions because
// it's impossible to "re-pass" varargs.
if (Ctor->getType()->getAs<FunctionProtoType>()->isVariadic())
return false;
// FIXME: Decide if we can do a delegation of a delegating constructor.
if (Ctor->isDelegatingConstructor())
return false;
return true;
}
/// EmitConstructorBody - Emits the body of the current constructor.
void CodeGenFunction::EmitConstructorBody(FunctionArgList &Args) {
const CXXConstructorDecl *Ctor = cast<CXXConstructorDecl>(CurGD.getDecl());
CXXCtorType CtorType = CurGD.getCtorType();
assert((CGM.getTarget().getCXXABI().hasConstructorVariants() ||
CtorType == Ctor_Complete) &&
"can only generate complete ctor for this ABI");
// Before we go any further, try the complete->base constructor
// delegation optimization.
if (CtorType == Ctor_Complete && IsConstructorDelegationValid(Ctor) &&
CGM.getTarget().getCXXABI().hasConstructorVariants()) {
if (CGDebugInfo *DI = getDebugInfo())
DI->EmitLocation(Builder, Ctor->getLocEnd());
EmitDelegateCXXConstructorCall(Ctor, Ctor_Base, Args, Ctor->getLocEnd());
return;
}
const FunctionDecl *Definition = 0;
Stmt *Body = Ctor->getBody(Definition);
assert(Definition == Ctor && "emitting wrong constructor body");
// Enter the function-try-block before the constructor prologue if
// applicable.
bool IsTryBody = (Body && isa<CXXTryStmt>(Body));
if (IsTryBody)
EnterCXXTryStmt(*cast<CXXTryStmt>(Body), true);
RegionCounter Cnt = getPGORegionCounter(Body);
Cnt.beginRegion(Builder);
RunCleanupsScope RunCleanups(*this);
// TODO: in restricted cases, we can emit the vbase initializers of
// a complete ctor and then delegate to the base ctor.
// Emit the constructor prologue, i.e. the base and member
// initializers.
Reimplement code generation for copying fields in the implicitly-generated copy constructor. Previously, Sema would perform some checking and instantiation to determine which copy constructors, etc., would be called, then CodeGen would attempt to figure out which copy constructor to call... but would get it wrong, or poke at an uninstantiated default argument, or fail in other ways. The new scheme is similar to what we now do for the implicit copy-assignment operator, where Sema performs all of the semantic analysis and builds specific ASTs that look similar to the ASTs we'd get from explicitly writing the copy constructor, so that CodeGen need only do a direct translation. However, it's not quite that simple because one cannot explicit write elementwise copy-construction of an array. So, I've extended CXXBaseOrMemberInitializer to contain a list of indexing variables used to copy-construct the elements. For example, if we have: struct A { A(const A&); }; struct B { A array[2][3]; }; then we generate an implicit copy assignment operator for B that looks something like this: B::B(const B &other) : array[i0][i1](other.array[i0][i1]) { } CodeGen will loop over the invented variables i0 and i1 to visit all elements in the array, so that each element in the destination array will be copy-constructed from the corresponding element in the source array. Of course, if we're dealing with arrays of scalars or class types with trivial copy-assignment operators, we just generate a memcpy rather than a loop. Fixes PR6928, PR5989, and PR6887. Boost.Regex now compiles and passes all of its regression tests. Conspicuously missing from this patch is handling for the exceptional case, where we need to destruct those objects that we have constructed. I'll address that case separately. llvm-svn: 103079
2010-05-05 13:51:00 +08:00
EmitCtorPrologue(Ctor, CtorType, Args);
// Emit the body of the statement.
if (IsTryBody)
EmitStmt(cast<CXXTryStmt>(Body)->getTryBlock());
else if (Body)
EmitStmt(Body);
// Emit any cleanup blocks associated with the member or base
// initializers, which includes (along the exceptional path) the
// destructors for those members and bases that were fully
// constructed.
RunCleanups.ForceCleanup();
if (IsTryBody)
ExitCXXTryStmt(*cast<CXXTryStmt>(Body), true);
}
namespace {
/// RAII object to indicate that codegen is copying the value representation
/// instead of the object representation. Useful when copying a struct or
/// class which has uninitialized members and we're only performing
/// lvalue-to-rvalue conversion on the object but not its members.
class CopyingValueRepresentation {
public:
explicit CopyingValueRepresentation(CodeGenFunction &CGF)
: CGF(CGF), SO(*CGF.SanOpts), OldSanOpts(CGF.SanOpts) {
SO.Bool = false;
SO.Enum = false;
CGF.SanOpts = &SO;
}
~CopyingValueRepresentation() {
CGF.SanOpts = OldSanOpts;
}
private:
CodeGenFunction &CGF;
SanitizerOptions SO;
const SanitizerOptions *OldSanOpts;
};
}
namespace {
class FieldMemcpyizer {
public:
FieldMemcpyizer(CodeGenFunction &CGF, const CXXRecordDecl *ClassDecl,
const VarDecl *SrcRec)
: CGF(CGF), ClassDecl(ClassDecl), SrcRec(SrcRec),
RecLayout(CGF.getContext().getASTRecordLayout(ClassDecl)),
FirstField(nullptr), LastField(nullptr), FirstFieldOffset(0),
LastFieldOffset(0), LastAddedFieldIndex(0) {}
static bool isMemcpyableField(FieldDecl *F) {
Qualifiers Qual = F->getType().getQualifiers();
if (Qual.hasVolatile() || Qual.hasObjCLifetime())
return false;
return true;
}
void addMemcpyableField(FieldDecl *F) {
if (!FirstField)
addInitialField(F);
else
addNextField(F);
}
CharUnits getMemcpySize() const {
unsigned LastFieldSize =
LastField->isBitField() ?
LastField->getBitWidthValue(CGF.getContext()) :
CGF.getContext().getTypeSize(LastField->getType());
uint64_t MemcpySizeBits =
LastFieldOffset + LastFieldSize - FirstFieldOffset +
CGF.getContext().getCharWidth() - 1;
CharUnits MemcpySize =
CGF.getContext().toCharUnitsFromBits(MemcpySizeBits);
return MemcpySize;
}
void emitMemcpy() {
// Give the subclass a chance to bail out if it feels the memcpy isn't
// worth it (e.g. Hasn't aggregated enough data).
if (!FirstField) {
return;
}
CharUnits Alignment;
if (FirstField->isBitField()) {
const CGRecordLayout &RL =
CGF.getTypes().getCGRecordLayout(FirstField->getParent());
const CGBitFieldInfo &BFInfo = RL.getBitFieldInfo(FirstField);
Alignment = CharUnits::fromQuantity(BFInfo.StorageAlignment);
} else {
Alignment = CGF.getContext().getDeclAlign(FirstField);
}
assert((CGF.getContext().toCharUnitsFromBits(FirstFieldOffset) %
Alignment) == 0 && "Bad field alignment.");
CharUnits MemcpySize = getMemcpySize();
QualType RecordTy = CGF.getContext().getTypeDeclType(ClassDecl);
llvm::Value *ThisPtr = CGF.LoadCXXThis();
LValue DestLV = CGF.MakeNaturalAlignAddrLValue(ThisPtr, RecordTy);
LValue Dest = CGF.EmitLValueForFieldInitialization(DestLV, FirstField);
llvm::Value *SrcPtr = CGF.Builder.CreateLoad(CGF.GetAddrOfLocalVar(SrcRec));
LValue SrcLV = CGF.MakeNaturalAlignAddrLValue(SrcPtr, RecordTy);
LValue Src = CGF.EmitLValueForFieldInitialization(SrcLV, FirstField);
emitMemcpyIR(Dest.isBitField() ? Dest.getBitFieldAddr() : Dest.getAddress(),
Src.isBitField() ? Src.getBitFieldAddr() : Src.getAddress(),
MemcpySize, Alignment);
reset();
}
void reset() {
FirstField = nullptr;
}
protected:
CodeGenFunction &CGF;
const CXXRecordDecl *ClassDecl;
private:
void emitMemcpyIR(llvm::Value *DestPtr, llvm::Value *SrcPtr,
CharUnits Size, CharUnits Alignment) {
llvm::PointerType *DPT = cast<llvm::PointerType>(DestPtr->getType());
llvm::Type *DBP =
llvm::Type::getInt8PtrTy(CGF.getLLVMContext(), DPT->getAddressSpace());
DestPtr = CGF.Builder.CreateBitCast(DestPtr, DBP);
llvm::PointerType *SPT = cast<llvm::PointerType>(SrcPtr->getType());
llvm::Type *SBP =
llvm::Type::getInt8PtrTy(CGF.getLLVMContext(), SPT->getAddressSpace());
SrcPtr = CGF.Builder.CreateBitCast(SrcPtr, SBP);
CGF.Builder.CreateMemCpy(DestPtr, SrcPtr, Size.getQuantity(),
Alignment.getQuantity());
}
void addInitialField(FieldDecl *F) {
FirstField = F;
LastField = F;
FirstFieldOffset = RecLayout.getFieldOffset(F->getFieldIndex());
LastFieldOffset = FirstFieldOffset;
LastAddedFieldIndex = F->getFieldIndex();
return;
}
void addNextField(FieldDecl *F) {
// For the most part, the following invariant will hold:
// F->getFieldIndex() == LastAddedFieldIndex + 1
// The one exception is that Sema won't add a copy-initializer for an
// unnamed bitfield, which will show up here as a gap in the sequence.
assert(F->getFieldIndex() >= LastAddedFieldIndex + 1 &&
"Cannot aggregate fields out of order.");
LastAddedFieldIndex = F->getFieldIndex();
// The 'first' and 'last' fields are chosen by offset, rather than field
// index. This allows the code to support bitfields, as well as regular
// fields.
uint64_t FOffset = RecLayout.getFieldOffset(F->getFieldIndex());
if (FOffset < FirstFieldOffset) {
FirstField = F;
FirstFieldOffset = FOffset;
} else if (FOffset > LastFieldOffset) {
LastField = F;
LastFieldOffset = FOffset;
}
}
const VarDecl *SrcRec;
const ASTRecordLayout &RecLayout;
FieldDecl *FirstField;
FieldDecl *LastField;
uint64_t FirstFieldOffset, LastFieldOffset;
unsigned LastAddedFieldIndex;
};
class ConstructorMemcpyizer : public FieldMemcpyizer {
private:
/// Get source argument for copy constructor. Returns null if not a copy
/// constructor.
static const VarDecl* getTrivialCopySource(const CXXConstructorDecl *CD,
FunctionArgList &Args) {
if (CD->isCopyOrMoveConstructor() && CD->isDefaulted())
return Args[Args.size() - 1];
return nullptr;
}
// Returns true if a CXXCtorInitializer represents a member initialization
// that can be rolled into a memcpy.
bool isMemberInitMemcpyable(CXXCtorInitializer *MemberInit) const {
if (!MemcpyableCtor)
return false;
FieldDecl *Field = MemberInit->getMember();
assert(Field && "No field for member init.");
QualType FieldType = Field->getType();
CXXConstructExpr *CE = dyn_cast<CXXConstructExpr>(MemberInit->getInit());
// Bail out on non-POD, not-trivially-constructable members.
if (!(CE && CE->getConstructor()->isTrivial()) &&
!(FieldType.isTriviallyCopyableType(CGF.getContext()) ||
FieldType->isReferenceType()))
return false;
// Bail out on volatile fields.
if (!isMemcpyableField(Field))
return false;
// Otherwise we're good.
return true;
}
public:
ConstructorMemcpyizer(CodeGenFunction &CGF, const CXXConstructorDecl *CD,
FunctionArgList &Args)
: FieldMemcpyizer(CGF, CD->getParent(), getTrivialCopySource(CD, Args)),
ConstructorDecl(CD),
MemcpyableCtor(CD->isDefaulted() &&
CD->isCopyOrMoveConstructor() &&
CGF.getLangOpts().getGC() == LangOptions::NonGC),
Args(Args) { }
void addMemberInitializer(CXXCtorInitializer *MemberInit) {
if (isMemberInitMemcpyable(MemberInit)) {
AggregatedInits.push_back(MemberInit);
addMemcpyableField(MemberInit->getMember());
} else {
emitAggregatedInits();
EmitMemberInitializer(CGF, ConstructorDecl->getParent(), MemberInit,
ConstructorDecl, Args);
}
}
void emitAggregatedInits() {
if (AggregatedInits.size() <= 1) {
// This memcpy is too small to be worthwhile. Fall back on default
// codegen.
if (!AggregatedInits.empty()) {
CopyingValueRepresentation CVR(CGF);
EmitMemberInitializer(CGF, ConstructorDecl->getParent(),
AggregatedInits[0], ConstructorDecl, Args);
}
reset();
return;
}
pushEHDestructors();
emitMemcpy();
AggregatedInits.clear();
}
void pushEHDestructors() {
llvm::Value *ThisPtr = CGF.LoadCXXThis();
QualType RecordTy = CGF.getContext().getTypeDeclType(ClassDecl);
LValue LHS = CGF.MakeNaturalAlignAddrLValue(ThisPtr, RecordTy);
for (unsigned i = 0; i < AggregatedInits.size(); ++i) {
QualType FieldType = AggregatedInits[i]->getMember()->getType();
QualType::DestructionKind dtorKind = FieldType.isDestructedType();
if (CGF.needsEHCleanup(dtorKind))
CGF.pushEHDestroy(dtorKind, LHS.getAddress(), FieldType);
}
}
void finish() {
emitAggregatedInits();
}
private:
const CXXConstructorDecl *ConstructorDecl;
bool MemcpyableCtor;
FunctionArgList &Args;
SmallVector<CXXCtorInitializer*, 16> AggregatedInits;
};
class AssignmentMemcpyizer : public FieldMemcpyizer {
private:
// Returns the memcpyable field copied by the given statement, if one
// exists. Otherwise returns null.
FieldDecl *getMemcpyableField(Stmt *S) {
if (!AssignmentsMemcpyable)
return nullptr;
if (BinaryOperator *BO = dyn_cast<BinaryOperator>(S)) {
// Recognise trivial assignments.
if (BO->getOpcode() != BO_Assign)
return nullptr;
MemberExpr *ME = dyn_cast<MemberExpr>(BO->getLHS());
if (!ME)
return nullptr;
FieldDecl *Field = dyn_cast<FieldDecl>(ME->getMemberDecl());
if (!Field || !isMemcpyableField(Field))
return nullptr;
Stmt *RHS = BO->getRHS();
if (ImplicitCastExpr *EC = dyn_cast<ImplicitCastExpr>(RHS))
RHS = EC->getSubExpr();
if (!RHS)
return nullptr;
MemberExpr *ME2 = dyn_cast<MemberExpr>(RHS);
if (dyn_cast<FieldDecl>(ME2->getMemberDecl()) != Field)
return nullptr;
return Field;
} else if (CXXMemberCallExpr *MCE = dyn_cast<CXXMemberCallExpr>(S)) {
CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(MCE->getCalleeDecl());
if (!(MD && (MD->isCopyAssignmentOperator() ||
MD->isMoveAssignmentOperator()) &&
MD->isTrivial()))
return nullptr;
MemberExpr *IOA = dyn_cast<MemberExpr>(MCE->getImplicitObjectArgument());
if (!IOA)
return nullptr;
FieldDecl *Field = dyn_cast<FieldDecl>(IOA->getMemberDecl());
if (!Field || !isMemcpyableField(Field))
return nullptr;
MemberExpr *Arg0 = dyn_cast<MemberExpr>(MCE->getArg(0));
if (!Arg0 || Field != dyn_cast<FieldDecl>(Arg0->getMemberDecl()))
return nullptr;
return Field;
} else if (CallExpr *CE = dyn_cast<CallExpr>(S)) {
FunctionDecl *FD = dyn_cast<FunctionDecl>(CE->getCalleeDecl());
if (!FD || FD->getBuiltinID() != Builtin::BI__builtin_memcpy)
return nullptr;
Expr *DstPtr = CE->getArg(0);
if (ImplicitCastExpr *DC = dyn_cast<ImplicitCastExpr>(DstPtr))
DstPtr = DC->getSubExpr();
UnaryOperator *DUO = dyn_cast<UnaryOperator>(DstPtr);
if (!DUO || DUO->getOpcode() != UO_AddrOf)
return nullptr;
MemberExpr *ME = dyn_cast<MemberExpr>(DUO->getSubExpr());
if (!ME)
return nullptr;
FieldDecl *Field = dyn_cast<FieldDecl>(ME->getMemberDecl());
if (!Field || !isMemcpyableField(Field))
return nullptr;
Expr *SrcPtr = CE->getArg(1);
if (ImplicitCastExpr *SC = dyn_cast<ImplicitCastExpr>(SrcPtr))
SrcPtr = SC->getSubExpr();
UnaryOperator *SUO = dyn_cast<UnaryOperator>(SrcPtr);
if (!SUO || SUO->getOpcode() != UO_AddrOf)
return nullptr;
MemberExpr *ME2 = dyn_cast<MemberExpr>(SUO->getSubExpr());
if (!ME2 || Field != dyn_cast<FieldDecl>(ME2->getMemberDecl()))
return nullptr;
return Field;
}
return nullptr;
}
bool AssignmentsMemcpyable;
SmallVector<Stmt*, 16> AggregatedStmts;
public:
AssignmentMemcpyizer(CodeGenFunction &CGF, const CXXMethodDecl *AD,
FunctionArgList &Args)
: FieldMemcpyizer(CGF, AD->getParent(), Args[Args.size() - 1]),
AssignmentsMemcpyable(CGF.getLangOpts().getGC() == LangOptions::NonGC) {
assert(Args.size() == 2);
}
void emitAssignment(Stmt *S) {
FieldDecl *F = getMemcpyableField(S);
if (F) {
addMemcpyableField(F);
AggregatedStmts.push_back(S);
} else {
emitAggregatedStmts();
CGF.EmitStmt(S);
}
}
void emitAggregatedStmts() {
if (AggregatedStmts.size() <= 1) {
if (!AggregatedStmts.empty()) {
CopyingValueRepresentation CVR(CGF);
CGF.EmitStmt(AggregatedStmts[0]);
}
reset();
}
emitMemcpy();
AggregatedStmts.clear();
}
void finish() {
emitAggregatedStmts();
}
};
}
/// EmitCtorPrologue - This routine generates necessary code to initialize
/// base classes and non-static data members belonging to this constructor.
void CodeGenFunction::EmitCtorPrologue(const CXXConstructorDecl *CD,
Reimplement code generation for copying fields in the implicitly-generated copy constructor. Previously, Sema would perform some checking and instantiation to determine which copy constructors, etc., would be called, then CodeGen would attempt to figure out which copy constructor to call... but would get it wrong, or poke at an uninstantiated default argument, or fail in other ways. The new scheme is similar to what we now do for the implicit copy-assignment operator, where Sema performs all of the semantic analysis and builds specific ASTs that look similar to the ASTs we'd get from explicitly writing the copy constructor, so that CodeGen need only do a direct translation. However, it's not quite that simple because one cannot explicit write elementwise copy-construction of an array. So, I've extended CXXBaseOrMemberInitializer to contain a list of indexing variables used to copy-construct the elements. For example, if we have: struct A { A(const A&); }; struct B { A array[2][3]; }; then we generate an implicit copy assignment operator for B that looks something like this: B::B(const B &other) : array[i0][i1](other.array[i0][i1]) { } CodeGen will loop over the invented variables i0 and i1 to visit all elements in the array, so that each element in the destination array will be copy-constructed from the corresponding element in the source array. Of course, if we're dealing with arrays of scalars or class types with trivial copy-assignment operators, we just generate a memcpy rather than a loop. Fixes PR6928, PR5989, and PR6887. Boost.Regex now compiles and passes all of its regression tests. Conspicuously missing from this patch is handling for the exceptional case, where we need to destruct those objects that we have constructed. I'll address that case separately. llvm-svn: 103079
2010-05-05 13:51:00 +08:00
CXXCtorType CtorType,
FunctionArgList &Args) {
if (CD->isDelegatingConstructor())
return EmitDelegatingCXXConstructorCall(CD, Args);
const CXXRecordDecl *ClassDecl = CD->getParent();
CXXConstructorDecl::init_const_iterator B = CD->init_begin(),
E = CD->init_end();
llvm::BasicBlock *BaseCtorContinueBB = nullptr;
if (ClassDecl->getNumVBases() &&
!CGM.getTarget().getCXXABI().hasConstructorVariants()) {
// The ABIs that don't have constructor variants need to put a branch
// before the virtual base initialization code.
BaseCtorContinueBB =
CGM.getCXXABI().EmitCtorCompleteObjectHandler(*this, ClassDecl);
assert(BaseCtorContinueBB);
}
// Virtual base initializers first.
for (; B != E && (*B)->isBaseInitializer() && (*B)->isBaseVirtual(); B++) {
EmitBaseInitializer(*this, ClassDecl, *B, CtorType);
}
if (BaseCtorContinueBB) {
// Complete object handler should continue to the remaining initializers.
Builder.CreateBr(BaseCtorContinueBB);
EmitBlock(BaseCtorContinueBB);
}
// Then, non-virtual base initializers.
for (; B != E && (*B)->isBaseInitializer(); B++) {
assert(!(*B)->isBaseVirtual());
EmitBaseInitializer(*this, ClassDecl, *B, CtorType);
}
InitializeVTablePointers(ClassDecl);
// And finally, initialize class members.
FieldConstructionScope FCS(*this, CXXThisValue);
ConstructorMemcpyizer CM(*this, CD, Args);
for (; B != E; B++) {
CXXCtorInitializer *Member = (*B);
assert(!Member->isBaseInitializer());
assert(Member->isAnyMemberInitializer() &&
"Delegating initializer on non-delegating constructor");
CM.addMemberInitializer(Member);
}
CM.finish();
}
static bool
FieldHasTrivialDestructorBody(ASTContext &Context, const FieldDecl *Field);
static bool
HasTrivialDestructorBody(ASTContext &Context,
const CXXRecordDecl *BaseClassDecl,
const CXXRecordDecl *MostDerivedClassDecl)
{
// If the destructor is trivial we don't have to check anything else.
if (BaseClassDecl->hasTrivialDestructor())
return true;
if (!BaseClassDecl->getDestructor()->hasTrivialBody())
return false;
// Check fields.
for (const auto *Field : BaseClassDecl->fields())
if (!FieldHasTrivialDestructorBody(Context, Field))
return false;
// Check non-virtual bases.
for (const auto &I : BaseClassDecl->bases()) {
if (I.isVirtual())
continue;
const CXXRecordDecl *NonVirtualBase =
cast<CXXRecordDecl>(I.getType()->castAs<RecordType>()->getDecl());
if (!HasTrivialDestructorBody(Context, NonVirtualBase,
MostDerivedClassDecl))
return false;
}
if (BaseClassDecl == MostDerivedClassDecl) {
// Check virtual bases.
for (const auto &I : BaseClassDecl->vbases()) {
const CXXRecordDecl *VirtualBase =
cast<CXXRecordDecl>(I.getType()->castAs<RecordType>()->getDecl());
if (!HasTrivialDestructorBody(Context, VirtualBase,
MostDerivedClassDecl))
return false;
}
}
return true;
}
static bool
FieldHasTrivialDestructorBody(ASTContext &Context,
const FieldDecl *Field)
{
QualType FieldBaseElementType = Context.getBaseElementType(Field->getType());
const RecordType *RT = FieldBaseElementType->getAs<RecordType>();
if (!RT)
return true;
CXXRecordDecl *FieldClassDecl = cast<CXXRecordDecl>(RT->getDecl());
return HasTrivialDestructorBody(Context, FieldClassDecl, FieldClassDecl);
}
/// CanSkipVTablePointerInitialization - Check whether we need to initialize
/// any vtable pointers before calling this destructor.
static bool CanSkipVTablePointerInitialization(ASTContext &Context,
const CXXDestructorDecl *Dtor) {
if (!Dtor->hasTrivialBody())
return false;
// Check the fields.
const CXXRecordDecl *ClassDecl = Dtor->getParent();
for (const auto *Field : ClassDecl->fields())
if (!FieldHasTrivialDestructorBody(Context, Field))
return false;
return true;
}
/// EmitDestructorBody - Emits the body of the current destructor.
void CodeGenFunction::EmitDestructorBody(FunctionArgList &Args) {
const CXXDestructorDecl *Dtor = cast<CXXDestructorDecl>(CurGD.getDecl());
CXXDtorType DtorType = CurGD.getDtorType();
// The call to operator delete in a deleting destructor happens
// outside of the function-try-block, which means it's always
// possible to delegate the destructor body to the complete
// destructor. Do so.
if (DtorType == Dtor_Deleting) {
EnterDtorCleanups(Dtor, Dtor_Deleting);
EmitCXXDestructorCall(Dtor, Dtor_Complete, /*ForVirtualBase=*/false,
/*Delegating=*/false, LoadCXXThis());
PopCleanupBlock();
return;
}
Stmt *Body = Dtor->getBody();
// If the body is a function-try-block, enter the try before
// anything else.
bool isTryBody = (Body && isa<CXXTryStmt>(Body));
if (isTryBody)
EnterCXXTryStmt(*cast<CXXTryStmt>(Body), true);
// Enter the epilogue cleanups.
RunCleanupsScope DtorEpilogue(*this);
// If this is the complete variant, just invoke the base variant;
// the epilogue will destruct the virtual bases. But we can't do
// this optimization if the body is a function-try-block, because
// we'd introduce *two* handler blocks. In the Microsoft ABI, we
// always delegate because we might not have a definition in this TU.
switch (DtorType) {
case Dtor_Deleting: llvm_unreachable("already handled deleting case");
case Dtor_Complete:
assert((Body || getTarget().getCXXABI().isMicrosoft()) &&
"can't emit a dtor without a body for non-Microsoft ABIs");
// Enter the cleanup scopes for virtual bases.
EnterDtorCleanups(Dtor, Dtor_Complete);
if (!isTryBody) {
EmitCXXDestructorCall(Dtor, Dtor_Base, /*ForVirtualBase=*/false,
/*Delegating=*/false, LoadCXXThis());
break;
}
// Fallthrough: act like we're in the base variant.
case Dtor_Base:
assert(Body);
RegionCounter Cnt = getPGORegionCounter(Body);
Cnt.beginRegion(Builder);
// Enter the cleanup scopes for fields and non-virtual bases.
EnterDtorCleanups(Dtor, Dtor_Base);
// Initialize the vtable pointers before entering the body.
if (!CanSkipVTablePointerInitialization(getContext(), Dtor))
InitializeVTablePointers(Dtor->getParent());
if (isTryBody)
EmitStmt(cast<CXXTryStmt>(Body)->getTryBlock());
else if (Body)
EmitStmt(Body);
else {
assert(Dtor->isImplicit() && "bodyless dtor not implicit");
// nothing to do besides what's in the epilogue
}
// -fapple-kext must inline any call to this dtor into
// the caller's body.
if (getLangOpts().AppleKext)
CurFn->addFnAttr(llvm::Attribute::AlwaysInline);
break;
}
// Jump out through the epilogue cleanups.
DtorEpilogue.ForceCleanup();
// Exit the try if applicable.
if (isTryBody)
ExitCXXTryStmt(*cast<CXXTryStmt>(Body), true);
}
void CodeGenFunction::emitImplicitAssignmentOperatorBody(FunctionArgList &Args) {
const CXXMethodDecl *AssignOp = cast<CXXMethodDecl>(CurGD.getDecl());
const Stmt *RootS = AssignOp->getBody();
assert(isa<CompoundStmt>(RootS) &&
"Body of an implicit assignment operator should be compound stmt.");
const CompoundStmt *RootCS = cast<CompoundStmt>(RootS);
LexicalScope Scope(*this, RootCS->getSourceRange());
AssignmentMemcpyizer AM(*this, AssignOp, Args);
for (auto *I : RootCS->body())
AM.emitAssignment(I);
AM.finish();
}
namespace {
/// Call the operator delete associated with the current destructor.
struct CallDtorDelete : EHScopeStack::Cleanup {
CallDtorDelete() {}
void Emit(CodeGenFunction &CGF, Flags flags) override {
const CXXDestructorDecl *Dtor = cast<CXXDestructorDecl>(CGF.CurCodeDecl);
const CXXRecordDecl *ClassDecl = Dtor->getParent();
CGF.EmitDeleteCall(Dtor->getOperatorDelete(), CGF.LoadCXXThis(),
CGF.getContext().getTagDeclType(ClassDecl));
}
};
struct CallDtorDeleteConditional : EHScopeStack::Cleanup {
llvm::Value *ShouldDeleteCondition;
public:
CallDtorDeleteConditional(llvm::Value *ShouldDeleteCondition)
: ShouldDeleteCondition(ShouldDeleteCondition) {
assert(ShouldDeleteCondition != nullptr);
}
void Emit(CodeGenFunction &CGF, Flags flags) override {
llvm::BasicBlock *callDeleteBB = CGF.createBasicBlock("dtor.call_delete");
llvm::BasicBlock *continueBB = CGF.createBasicBlock("dtor.continue");
llvm::Value *ShouldCallDelete
= CGF.Builder.CreateIsNull(ShouldDeleteCondition);
CGF.Builder.CreateCondBr(ShouldCallDelete, continueBB, callDeleteBB);
CGF.EmitBlock(callDeleteBB);
const CXXDestructorDecl *Dtor = cast<CXXDestructorDecl>(CGF.CurCodeDecl);
const CXXRecordDecl *ClassDecl = Dtor->getParent();
CGF.EmitDeleteCall(Dtor->getOperatorDelete(), CGF.LoadCXXThis(),
CGF.getContext().getTagDeclType(ClassDecl));
CGF.Builder.CreateBr(continueBB);
CGF.EmitBlock(continueBB);
}
};
class DestroyField : public EHScopeStack::Cleanup {
const FieldDecl *field;
CodeGenFunction::Destroyer *destroyer;
bool useEHCleanupForArray;
public:
DestroyField(const FieldDecl *field, CodeGenFunction::Destroyer *destroyer,
bool useEHCleanupForArray)
: field(field), destroyer(destroyer),
useEHCleanupForArray(useEHCleanupForArray) {}
void Emit(CodeGenFunction &CGF, Flags flags) override {
// Find the address of the field.
llvm::Value *thisValue = CGF.LoadCXXThis();
QualType RecordTy = CGF.getContext().getTagDeclType(field->getParent());
LValue ThisLV = CGF.MakeAddrLValue(thisValue, RecordTy);
LValue LV = CGF.EmitLValueForField(ThisLV, field);
assert(LV.isSimple());
CGF.emitDestroy(LV.getAddress(), field->getType(), destroyer,
flags.isForNormalCleanup() && useEHCleanupForArray);
}
};
}
/// \brief Emit all code that comes at the end of class's
/// destructor. This is to call destructors on members and base classes
/// in reverse order of their construction.
void CodeGenFunction::EnterDtorCleanups(const CXXDestructorDecl *DD,
CXXDtorType DtorType) {
assert((!DD->isTrivial() || DD->hasAttr<DLLExportAttr>()) &&
"Should not emit dtor epilogue for non-exported trivial dtor!");
// The deleting-destructor phase just needs to call the appropriate
// operator delete that Sema picked up.
if (DtorType == Dtor_Deleting) {
assert(DD->getOperatorDelete() &&
"operator delete missing - EnterDtorCleanups");
if (CXXStructorImplicitParamValue) {
// If there is an implicit param to the deleting dtor, it's a boolean
// telling whether we should call delete at the end of the dtor.
EHStack.pushCleanup<CallDtorDeleteConditional>(
NormalAndEHCleanup, CXXStructorImplicitParamValue);
} else {
EHStack.pushCleanup<CallDtorDelete>(NormalAndEHCleanup);
}
return;
}
const CXXRecordDecl *ClassDecl = DD->getParent();
// Unions have no bases and do not call field destructors.
if (ClassDecl->isUnion())
return;
// The complete-destructor phase just destructs all the virtual bases.
if (DtorType == Dtor_Complete) {
// We push them in the forward order so that they'll be popped in
// the reverse order.
for (const auto &Base : ClassDecl->vbases()) {
CXXRecordDecl *BaseClassDecl
= cast<CXXRecordDecl>(Base.getType()->getAs<RecordType>()->getDecl());
// Ignore trivial destructors.
if (BaseClassDecl->hasTrivialDestructor())
continue;
EHStack.pushCleanup<CallBaseDtor>(NormalAndEHCleanup,
BaseClassDecl,
/*BaseIsVirtual*/ true);
}
return;
}
assert(DtorType == Dtor_Base);
// Destroy non-virtual bases.
for (const auto &Base : ClassDecl->bases()) {
// Ignore virtual bases.
if (Base.isVirtual())
continue;
CXXRecordDecl *BaseClassDecl = Base.getType()->getAsCXXRecordDecl();
// Ignore trivial destructors.
if (BaseClassDecl->hasTrivialDestructor())
continue;
EHStack.pushCleanup<CallBaseDtor>(NormalAndEHCleanup,
BaseClassDecl,
/*BaseIsVirtual*/ false);
}
// Destroy direct fields.
for (const auto *Field : ClassDecl->fields()) {
QualType type = Field->getType();
QualType::DestructionKind dtorKind = type.isDestructedType();
if (!dtorKind) continue;
// Anonymous union members do not have their destructors called.
const RecordType *RT = type->getAsUnionType();
if (RT && RT->getDecl()->isAnonymousStructOrUnion()) continue;
CleanupKind cleanupKind = getCleanupKind(dtorKind);
EHStack.pushCleanup<DestroyField>(cleanupKind, Field,
getDestroyer(dtorKind),
cleanupKind & EHCleanup);
}
}
/// EmitCXXAggrConstructorCall - Emit a loop to call a particular
/// constructor for each of several members of an array.
///
/// \param ctor the constructor to call for each element
/// \param arrayType the type of the array to initialize
/// \param arrayBegin an arrayType*
/// \param zeroInitialize true if each element should be
/// zero-initialized before it is constructed
void CodeGenFunction::EmitCXXAggrConstructorCall(
const CXXConstructorDecl *ctor, const ConstantArrayType *arrayType,
llvm::Value *arrayBegin, const CXXConstructExpr *E, bool zeroInitialize) {
QualType elementType;
llvm::Value *numElements =
emitArrayLength(arrayType, elementType, arrayBegin);
EmitCXXAggrConstructorCall(ctor, numElements, arrayBegin, E, zeroInitialize);
}
/// EmitCXXAggrConstructorCall - Emit a loop to call a particular
/// constructor for each of several members of an array.
///
/// \param ctor the constructor to call for each element
/// \param numElements the number of elements in the array;
/// may be zero
/// \param arrayBegin a T*, where T is the type constructed by ctor
/// \param zeroInitialize true if each element should be
/// zero-initialized before it is constructed
void CodeGenFunction::EmitCXXAggrConstructorCall(const CXXConstructorDecl *ctor,
llvm::Value *numElements,
llvm::Value *arrayBegin,
const CXXConstructExpr *E,
bool zeroInitialize) {
// It's legal for numElements to be zero. This can happen both
// dynamically, because x can be zero in 'new A[x]', and statically,
// because of GCC extensions that permit zero-length arrays. There
// are probably legitimate places where we could assume that this
// doesn't happen, but it's not clear that it's worth it.
llvm::BranchInst *zeroCheckBranch = nullptr;
// Optimize for a constant count.
llvm::ConstantInt *constantCount
= dyn_cast<llvm::ConstantInt>(numElements);
if (constantCount) {
// Just skip out if the constant count is zero.
if (constantCount->isZero()) return;
// Otherwise, emit the check.
} else {
llvm::BasicBlock *loopBB = createBasicBlock("new.ctorloop");
llvm::Value *iszero = Builder.CreateIsNull(numElements, "isempty");
zeroCheckBranch = Builder.CreateCondBr(iszero, loopBB, loopBB);
EmitBlock(loopBB);
}
// Find the end of the array.
llvm::Value *arrayEnd = Builder.CreateInBoundsGEP(arrayBegin, numElements,
"arrayctor.end");
// Enter the loop, setting up a phi for the current location to initialize.
llvm::BasicBlock *entryBB = Builder.GetInsertBlock();
llvm::BasicBlock *loopBB = createBasicBlock("arrayctor.loop");
EmitBlock(loopBB);
llvm::PHINode *cur = Builder.CreatePHI(arrayBegin->getType(), 2,
"arrayctor.cur");
cur->addIncoming(arrayBegin, entryBB);
// Inside the loop body, emit the constructor call on the array element.
QualType type = getContext().getTypeDeclType(ctor->getParent());
// Zero initialize the storage, if requested.
if (zeroInitialize)
EmitNullInitialization(cur, type);
// C++ [class.temporary]p4:
// There are two contexts in which temporaries are destroyed at a different
// point than the end of the full-expression. The first context is when a
// default constructor is called to initialize an element of an array.
// If the constructor has one or more default arguments, the destruction of
// every temporary created in a default argument expression is sequenced
// before the construction of the next array element, if any.
{
RunCleanupsScope Scope(*this);
// Evaluate the constructor and its arguments in a regular
// partial-destroy cleanup.
if (getLangOpts().Exceptions &&
!ctor->getParent()->hasTrivialDestructor()) {
Destroyer *destroyer = destroyCXXObject;
pushRegularPartialArrayCleanup(arrayBegin, cur, type, *destroyer);
}
EmitCXXConstructorCall(ctor, Ctor_Complete, /*ForVirtualBase=*/false,
/*Delegating=*/false, cur, E);
}
// Go to the next element.
llvm::Value *next =
Builder.CreateInBoundsGEP(cur, llvm::ConstantInt::get(SizeTy, 1),
"arrayctor.next");
cur->addIncoming(next, Builder.GetInsertBlock());
// Check whether that's the end of the loop.
llvm::Value *done = Builder.CreateICmpEQ(next, arrayEnd, "arrayctor.done");
llvm::BasicBlock *contBB = createBasicBlock("arrayctor.cont");
Builder.CreateCondBr(done, contBB, loopBB);
// Patch the earlier check to skip over the loop.
if (zeroCheckBranch) zeroCheckBranch->setSuccessor(0, contBB);
EmitBlock(contBB);
}
void CodeGenFunction::destroyCXXObject(CodeGenFunction &CGF,
llvm::Value *addr,
QualType type) {
const RecordType *rtype = type->castAs<RecordType>();
const CXXRecordDecl *record = cast<CXXRecordDecl>(rtype->getDecl());
const CXXDestructorDecl *dtor = record->getDestructor();
assert(!dtor->isTrivial());
CGF.EmitCXXDestructorCall(dtor, Dtor_Complete, /*for vbase*/ false,
/*Delegating=*/false, addr);
}
void CodeGenFunction::EmitCXXConstructorCall(const CXXConstructorDecl *D,
CXXCtorType Type,
bool ForVirtualBase,
bool Delegating, llvm::Value *This,
const CXXConstructExpr *E) {
// If this is a trivial constructor, just emit what's needed.
if (D->isTrivial()) {
if (E->getNumArgs() == 0) {
// Trivial default constructor, no codegen required.
assert(D->isDefaultConstructor() &&
"trivial 0-arg ctor not a default ctor");
return;
}
assert(E->getNumArgs() == 1 && "unexpected argcount for trivial ctor");
assert(D->isCopyOrMoveConstructor() &&
"trivial 1-arg ctor not a copy/move ctor");
const Expr *Arg = E->getArg(0);
QualType Ty = Arg->getType();
llvm::Value *Src = EmitLValue(Arg).getAddress();
EmitAggregateCopy(This, Src, Ty);
return;
}
// C++11 [class.mfct.non-static]p2:
// If a non-static member function of a class X is called for an object that
// is not of type X, or of a type derived from X, the behavior is undefined.
// FIXME: Provide a source location here.
EmitTypeCheck(CodeGenFunction::TCK_ConstructorCall, SourceLocation(), This,
getContext().getRecordType(D->getParent()));
CallArgList Args;
// Push the this ptr.
Args.add(RValue::get(This), D->getThisType(getContext()));
// Add the rest of the user-supplied arguments.
const FunctionProtoType *FPT = D->getType()->castAs<FunctionProtoType>();
EmitCallArgs(Args, FPT, E->arg_begin(), E->arg_end(), E->getConstructor());
// Insert any ABI-specific implicit constructor arguments.
unsigned ExtraArgs = CGM.getCXXABI().addImplicitConstructorArgs(
*this, D, Type, ForVirtualBase, Delegating, Args);
// Emit the call.
llvm::Value *Callee = CGM.getAddrOfCXXStructor(D, getFromCtorType(Type));
const CGFunctionInfo &Info =
CGM.getTypes().arrangeCXXConstructorCall(Args, D, Type, ExtraArgs);
EmitCall(Info, Callee, ReturnValueSlot(), Args, D);
}
void
CodeGenFunction::EmitSynthesizedCXXCopyCtorCall(const CXXConstructorDecl *D,
llvm::Value *This, llvm::Value *Src,
const CXXConstructExpr *E) {
if (D->isTrivial()) {
assert(E->getNumArgs() == 1 && "unexpected argcount for trivial ctor");
assert(D->isCopyOrMoveConstructor() &&
"trivial 1-arg ctor not a copy/move ctor");
EmitAggregateCopy(This, Src, E->arg_begin()->getType());
return;
}
llvm::Value *Callee = CGM.getAddrOfCXXStructor(D, StructorType::Complete);
assert(D->isInstance() &&
"Trying to emit a member call expr on a static method!");
const FunctionProtoType *FPT = D->getType()->castAs<FunctionProtoType>();
CallArgList Args;
// Push the this ptr.
Args.add(RValue::get(This), D->getThisType(getContext()));
// Push the src ptr.
QualType QT = *(FPT->param_type_begin());
llvm::Type *t = CGM.getTypes().ConvertType(QT);
Src = Builder.CreateBitCast(Src, t);
Args.add(RValue::get(Src), QT);
// Skip over first argument (Src).
EmitCallArgs(Args, FPT, E->arg_begin() + 1, E->arg_end(), E->getConstructor(),
/*ParamsToSkip*/ 1);
EmitCall(CGM.getTypes().arrangeCXXMethodCall(Args, FPT, RequiredArgs::All),
Callee, ReturnValueSlot(), Args, D);
}
void
CodeGenFunction::EmitDelegateCXXConstructorCall(const CXXConstructorDecl *Ctor,
CXXCtorType CtorType,
const FunctionArgList &Args,
SourceLocation Loc) {
CallArgList DelegateArgs;
FunctionArgList::const_iterator I = Args.begin(), E = Args.end();
assert(I != E && "no parameters to constructor");
// this
DelegateArgs.add(RValue::get(LoadCXXThis()), (*I)->getType());
++I;
// vtt
if (llvm::Value *VTT = GetVTTParameter(GlobalDecl(Ctor, CtorType),
/*ForVirtualBase=*/false,
/*Delegating=*/true)) {
QualType VoidPP = getContext().getPointerType(getContext().VoidPtrTy);
DelegateArgs.add(RValue::get(VTT), VoidPP);
if (CGM.getCXXABI().NeedsVTTParameter(CurGD)) {
assert(I != E && "cannot skip vtt parameter, already done with args");
assert((*I)->getType() == VoidPP && "skipping parameter not of vtt type");
++I;
}
}
// Explicit arguments.
for (; I != E; ++I) {
const VarDecl *param = *I;
// FIXME: per-argument source location
EmitDelegateCallArg(DelegateArgs, param, Loc);
}
llvm::Value *Callee =
CGM.getAddrOfCXXStructor(Ctor, getFromCtorType(CtorType));
EmitCall(CGM.getTypes()
.arrangeCXXStructorDeclaration(Ctor, getFromCtorType(CtorType)),
Callee, ReturnValueSlot(), DelegateArgs, Ctor);
}
namespace {
struct CallDelegatingCtorDtor : EHScopeStack::Cleanup {
const CXXDestructorDecl *Dtor;
llvm::Value *Addr;
CXXDtorType Type;
CallDelegatingCtorDtor(const CXXDestructorDecl *D, llvm::Value *Addr,
CXXDtorType Type)
: Dtor(D), Addr(Addr), Type(Type) {}
void Emit(CodeGenFunction &CGF, Flags flags) override {
CGF.EmitCXXDestructorCall(Dtor, Type, /*ForVirtualBase=*/false,
/*Delegating=*/true, Addr);
}
};
}
void
CodeGenFunction::EmitDelegatingCXXConstructorCall(const CXXConstructorDecl *Ctor,
const FunctionArgList &Args) {
assert(Ctor->isDelegatingConstructor());
llvm::Value *ThisPtr = LoadCXXThis();
QualType Ty = getContext().getTagDeclType(Ctor->getParent());
CharUnits Alignment = getContext().getTypeAlignInChars(Ty);
AggValueSlot AggSlot =
AggValueSlot::forAddr(ThisPtr, Alignment, Qualifiers(),
AggValueSlot::IsDestructed,
AggValueSlot::DoesNotNeedGCBarriers,
AggValueSlot::IsNotAliased);
EmitAggExpr(Ctor->init_begin()[0]->getInit(), AggSlot);
const CXXRecordDecl *ClassDecl = Ctor->getParent();
if (CGM.getLangOpts().Exceptions && !ClassDecl->hasTrivialDestructor()) {
CXXDtorType Type =
CurGD.getCtorType() == Ctor_Complete ? Dtor_Complete : Dtor_Base;
EHStack.pushCleanup<CallDelegatingCtorDtor>(EHCleanup,
ClassDecl->getDestructor(),
ThisPtr, Type);
}
}
void CodeGenFunction::EmitCXXDestructorCall(const CXXDestructorDecl *DD,
CXXDtorType Type,
bool ForVirtualBase,
bool Delegating,
llvm::Value *This) {
CGM.getCXXABI().EmitDestructorCall(*this, DD, Type, ForVirtualBase,
Delegating, This);
}
namespace {
struct CallLocalDtor : EHScopeStack::Cleanup {
const CXXDestructorDecl *Dtor;
llvm::Value *Addr;
CallLocalDtor(const CXXDestructorDecl *D, llvm::Value *Addr)
: Dtor(D), Addr(Addr) {}
void Emit(CodeGenFunction &CGF, Flags flags) override {
CGF.EmitCXXDestructorCall(Dtor, Dtor_Complete,
/*ForVirtualBase=*/false,
/*Delegating=*/false, Addr);
}
};
}
void CodeGenFunction::PushDestructorCleanup(const CXXDestructorDecl *D,
llvm::Value *Addr) {
EHStack.pushCleanup<CallLocalDtor>(NormalAndEHCleanup, D, Addr);
}
void CodeGenFunction::PushDestructorCleanup(QualType T, llvm::Value *Addr) {
CXXRecordDecl *ClassDecl = T->getAsCXXRecordDecl();
if (!ClassDecl) return;
if (ClassDecl->hasTrivialDestructor()) return;
const CXXDestructorDecl *D = ClassDecl->getDestructor();
assert(D && D->isUsed() && "destructor not marked as used!");
PushDestructorCleanup(D, Addr);
}
void
CodeGenFunction::InitializeVTablePointer(BaseSubobject Base,
const CXXRecordDecl *NearestVBase,
CharUnits OffsetFromNearestVBase,
const CXXRecordDecl *VTableClass) {
// Compute the address point.
bool NeedsVirtualOffset;
llvm::Value *VTableAddressPoint =
CGM.getCXXABI().getVTableAddressPointInStructor(
*this, VTableClass, Base, NearestVBase, NeedsVirtualOffset);
if (!VTableAddressPoint)
return;
// Compute where to store the address point.
llvm::Value *VirtualOffset = nullptr;
CharUnits NonVirtualOffset = CharUnits::Zero();
if (NeedsVirtualOffset) {
// We need to use the virtual base offset offset because the virtual base
// might have a different offset in the most derived class.
VirtualOffset = CGM.getCXXABI().GetVirtualBaseClassOffset(*this,
LoadCXXThis(),
VTableClass,
NearestVBase);
NonVirtualOffset = OffsetFromNearestVBase;
} else {
// We can just use the base offset in the complete class.
NonVirtualOffset = Base.getBaseOffset();
}
// Apply the offsets.
llvm::Value *VTableField = LoadCXXThis();
if (!NonVirtualOffset.isZero() || VirtualOffset)
VTableField = ApplyNonVirtualAndVirtualOffset(*this, VTableField,
NonVirtualOffset,
VirtualOffset);
// Finally, store the address point.
llvm::Type *AddressPointPtrTy =
VTableAddressPoint->getType()->getPointerTo();
VTableField = Builder.CreateBitCast(VTableField, AddressPointPtrTy);
llvm::StoreInst *Store = Builder.CreateStore(VTableAddressPoint, VTableField);
CGM.DecorateInstruction(Store, CGM.getTBAAInfoForVTablePtr());
}
void
CodeGenFunction::InitializeVTablePointers(BaseSubobject Base,
const CXXRecordDecl *NearestVBase,
CharUnits OffsetFromNearestVBase,
bool BaseIsNonVirtualPrimaryBase,
const CXXRecordDecl *VTableClass,
VisitedVirtualBasesSetTy& VBases) {
// If this base is a non-virtual primary base the address point has already
// been set.
if (!BaseIsNonVirtualPrimaryBase) {
// Initialize the vtable pointer for this base.
InitializeVTablePointer(Base, NearestVBase, OffsetFromNearestVBase,
VTableClass);
}
const CXXRecordDecl *RD = Base.getBase();
// Traverse bases.
for (const auto &I : RD->bases()) {
CXXRecordDecl *BaseDecl
= cast<CXXRecordDecl>(I.getType()->getAs<RecordType>()->getDecl());
// Ignore classes without a vtable.
if (!BaseDecl->isDynamicClass())
continue;
CharUnits BaseOffset;
CharUnits BaseOffsetFromNearestVBase;
bool BaseDeclIsNonVirtualPrimaryBase;
if (I.isVirtual()) {
// Check if we've visited this virtual base before.
if (!VBases.insert(BaseDecl))
continue;
const ASTRecordLayout &Layout =
getContext().getASTRecordLayout(VTableClass);
BaseOffset = Layout.getVBaseClassOffset(BaseDecl);
BaseOffsetFromNearestVBase = CharUnits::Zero();
BaseDeclIsNonVirtualPrimaryBase = false;
} else {
const ASTRecordLayout &Layout = getContext().getASTRecordLayout(RD);
BaseOffset = Base.getBaseOffset() + Layout.getBaseClassOffset(BaseDecl);
BaseOffsetFromNearestVBase =
OffsetFromNearestVBase + Layout.getBaseClassOffset(BaseDecl);
BaseDeclIsNonVirtualPrimaryBase = Layout.getPrimaryBase() == BaseDecl;
}
InitializeVTablePointers(BaseSubobject(BaseDecl, BaseOffset),
I.isVirtual() ? BaseDecl : NearestVBase,
BaseOffsetFromNearestVBase,
BaseDeclIsNonVirtualPrimaryBase,
VTableClass, VBases);
}
}
void CodeGenFunction::InitializeVTablePointers(const CXXRecordDecl *RD) {
// Ignore classes without a vtable.
if (!RD->isDynamicClass())
return;
// Initialize the vtable pointers for this class and all of its bases.
VisitedVirtualBasesSetTy VBases;
InitializeVTablePointers(BaseSubobject(RD, CharUnits::Zero()),
/*NearestVBase=*/nullptr,
/*OffsetFromNearestVBase=*/CharUnits::Zero(),
/*BaseIsNonVirtualPrimaryBase=*/false, RD, VBases);
if (RD->getNumVBases())
CGM.getCXXABI().initializeHiddenVirtualInheritanceMembers(*this, RD);
}
llvm::Value *CodeGenFunction::GetVTablePtr(llvm::Value *This,
llvm::Type *Ty) {
llvm::Value *VTablePtrSrc = Builder.CreateBitCast(This, Ty->getPointerTo());
llvm::Instruction *VTable = Builder.CreateLoad(VTablePtrSrc, "vtable");
CGM.DecorateInstruction(VTable, CGM.getTBAAInfoForVTablePtr());
return VTable;
}
// FIXME: Ideally Expr::IgnoreParenNoopCasts should do this, but it doesn't do
// quite what we want.
static const Expr *skipNoOpCastsAndParens(const Expr *E) {
while (true) {
if (const ParenExpr *PE = dyn_cast<ParenExpr>(E)) {
E = PE->getSubExpr();
continue;
}
if (const CastExpr *CE = dyn_cast<CastExpr>(E)) {
if (CE->getCastKind() == CK_NoOp) {
E = CE->getSubExpr();
continue;
}
}
if (const UnaryOperator *UO = dyn_cast<UnaryOperator>(E)) {
if (UO->getOpcode() == UO_Extension) {
E = UO->getSubExpr();
continue;
}
}
return E;
}
}
bool
CodeGenFunction::CanDevirtualizeMemberFunctionCall(const Expr *Base,
const CXXMethodDecl *MD) {
// When building with -fapple-kext, all calls must go through the vtable since
// the kernel linker can do runtime patching of vtables.
if (getLangOpts().AppleKext)
return false;
// If the most derived class is marked final, we know that no subclass can
// override this member function and so we can devirtualize it. For example:
//
// struct A { virtual void f(); }
// struct B final : A { };
//
// void f(B *b) {
// b->f();
// }
//
const CXXRecordDecl *MostDerivedClassDecl = Base->getBestDynamicClassType();
if (MostDerivedClassDecl->hasAttr<FinalAttr>())
return true;
// If the member function is marked 'final', we know that it can't be
// overridden and can therefore devirtualize it.
if (MD->hasAttr<FinalAttr>())
return true;
// Similarly, if the class itself is marked 'final' it can't be overridden
// and we can therefore devirtualize the member function call.
if (MD->getParent()->hasAttr<FinalAttr>())
return true;
Base = skipNoOpCastsAndParens(Base);
if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Base)) {
if (const VarDecl *VD = dyn_cast<VarDecl>(DRE->getDecl())) {
// This is a record decl. We know the type and can devirtualize it.
return VD->getType()->isRecordType();
}
return false;
}
// We can devirtualize calls on an object accessed by a class member access
// expression, since by C++11 [basic.life]p6 we know that it can't refer to
// a derived class object constructed in the same location.
if (const MemberExpr *ME = dyn_cast<MemberExpr>(Base))
if (const ValueDecl *VD = dyn_cast<ValueDecl>(ME->getMemberDecl()))
return VD->getType()->isRecordType();
// We can always devirtualize calls on temporary object expressions.
if (isa<CXXConstructExpr>(Base))
return true;
// And calls on bound temporaries.
if (isa<CXXBindTemporaryExpr>(Base))
return true;
// Check if this is a call expr that returns a record type.
if (const CallExpr *CE = dyn_cast<CallExpr>(Base))
return CE->getCallReturnType()->isRecordType();
// We can't devirtualize the call.
return false;
}
llvm::Value *
CodeGenFunction::EmitCXXOperatorMemberCallee(const CXXOperatorCallExpr *E,
const CXXMethodDecl *MD,
llvm::Value *This) {
llvm::FunctionType *fnType =
CGM.getTypes().GetFunctionType(
CGM.getTypes().arrangeCXXMethodDeclaration(MD));
if (MD->isVirtual() && !CanDevirtualizeMemberFunctionCall(E->getArg(0), MD))
return CGM.getCXXABI().getVirtualFunctionPointer(*this, MD, This, fnType);
return CGM.GetAddrOfFunction(MD, fnType);
}
Implement conversion to function pointer for generic lambdas without captures. The general strategy is to create template versions of the conversion function and static invoker and then during template argument deduction of the conversion function, create the corresponding call-operator and static invoker specializations, and when the conversion function is marked referenced generate the body of the conversion function using the corresponding static-invoker specialization. Similarly, Codegen does something similar - when asked to emit the IR for a specialized static invoker of a generic lambda, it forwards emission to the corresponding call operator. This patch has been reviewed in person both by Doug and Richard. Richard gave me the LGTM. A few minor changes: - per Richard's request i added a simple check to gracefully inform that captures (init, explicit or default) have not been added to generic lambdas just yet (instead of the assertion violation). - I removed a few lines of code that added the call operators instantiated parameters to the currentinstantiationscope. Not only did it not handle parameter packs, but it is more relevant in the patch for nested lambdas which will follow this one, and fix that problem more comprehensively. - Doug had commented that the original implementation strategy of using the TypeSourceInfo of the call operator to create the static-invoker was flawed and allowed const as a member qualifier to creep into the type of the static-invoker. I currently kludge around it - but after my initial discussion with Doug, with a follow up session with Richard, I have added a FIXME so that a more elegant solution that involves the use of TrivialTypeSourceInfo call followed by the correct wiring of the template parameters to the functionprototypeloc is forthcoming. Thanks! llvm-svn: 191634
2013-09-29 16:45:24 +08:00
void CodeGenFunction::EmitForwardingCallToLambda(
const CXXMethodDecl *callOperator,
CallArgList &callArgs) {
// Get the address of the call operator.
const CGFunctionInfo &calleeFnInfo =
CGM.getTypes().arrangeCXXMethodDeclaration(callOperator);
llvm::Value *callee =
CGM.GetAddrOfFunction(GlobalDecl(callOperator),
CGM.getTypes().GetFunctionType(calleeFnInfo));
// Prepare the return slot.
const FunctionProtoType *FPT =
callOperator->getType()->castAs<FunctionProtoType>();
QualType resultType = FPT->getReturnType();
ReturnValueSlot returnSlot;
if (!resultType->isVoidType() &&
calleeFnInfo.getReturnInfo().getKind() == ABIArgInfo::Indirect &&
!hasScalarEvaluationKind(calleeFnInfo.getReturnType()))
returnSlot = ReturnValueSlot(ReturnValue, resultType.isVolatileQualified());
// We don't need to separately arrange the call arguments because
// the call can't be variadic anyway --- it's impossible to forward
// variadic arguments.
// Now emit our call.
RValue RV = EmitCall(calleeFnInfo, callee, returnSlot,
callArgs, callOperator);
// If necessary, copy the returned value into the slot.
if (!resultType->isVoidType() && returnSlot.isNull())
EmitReturnOfRValue(RV, resultType);
else
EmitBranchThroughCleanup(ReturnBlock);
}
void CodeGenFunction::EmitLambdaBlockInvokeBody() {
const BlockDecl *BD = BlockInfo->getBlockDecl();
const VarDecl *variable = BD->capture_begin()->getVariable();
const CXXRecordDecl *Lambda = variable->getType()->getAsCXXRecordDecl();
// Start building arguments for forwarding call
CallArgList CallArgs;
QualType ThisType = getContext().getPointerType(getContext().getRecordType(Lambda));
llvm::Value *ThisPtr = GetAddrOfBlockDecl(variable, false);
CallArgs.add(RValue::get(ThisPtr), ThisType);
// Add the rest of the parameters.
for (auto param : BD->params())
EmitDelegateCallArg(CallArgs, param, param->getLocStart());
Implement conversion to function pointer for generic lambdas without captures. The general strategy is to create template versions of the conversion function and static invoker and then during template argument deduction of the conversion function, create the corresponding call-operator and static invoker specializations, and when the conversion function is marked referenced generate the body of the conversion function using the corresponding static-invoker specialization. Similarly, Codegen does something similar - when asked to emit the IR for a specialized static invoker of a generic lambda, it forwards emission to the corresponding call operator. This patch has been reviewed in person both by Doug and Richard. Richard gave me the LGTM. A few minor changes: - per Richard's request i added a simple check to gracefully inform that captures (init, explicit or default) have not been added to generic lambdas just yet (instead of the assertion violation). - I removed a few lines of code that added the call operators instantiated parameters to the currentinstantiationscope. Not only did it not handle parameter packs, but it is more relevant in the patch for nested lambdas which will follow this one, and fix that problem more comprehensively. - Doug had commented that the original implementation strategy of using the TypeSourceInfo of the call operator to create the static-invoker was flawed and allowed const as a member qualifier to creep into the type of the static-invoker. I currently kludge around it - but after my initial discussion with Doug, with a follow up session with Richard, I have added a FIXME so that a more elegant solution that involves the use of TrivialTypeSourceInfo call followed by the correct wiring of the template parameters to the functionprototypeloc is forthcoming. Thanks! llvm-svn: 191634
2013-09-29 16:45:24 +08:00
assert(!Lambda->isGenericLambda() &&
"generic lambda interconversion to block not implemented");
EmitForwardingCallToLambda(Lambda->getLambdaCallOperator(), CallArgs);
}
void CodeGenFunction::EmitLambdaToBlockPointerBody(FunctionArgList &Args) {
if (cast<CXXMethodDecl>(CurCodeDecl)->isVariadic()) {
// FIXME: Making this work correctly is nasty because it requires either
// cloning the body of the call operator or making the call operator forward.
CGM.ErrorUnsupported(CurCodeDecl, "lambda conversion to variadic function");
return;
}
EmitFunctionBody(Args, cast<FunctionDecl>(CurGD.getDecl())->getBody());
}
void CodeGenFunction::EmitLambdaDelegatingInvokeBody(const CXXMethodDecl *MD) {
const CXXRecordDecl *Lambda = MD->getParent();
// Start building arguments for forwarding call
CallArgList CallArgs;
QualType ThisType = getContext().getPointerType(getContext().getRecordType(Lambda));
llvm::Value *ThisPtr = llvm::UndefValue::get(getTypes().ConvertType(ThisType));
CallArgs.add(RValue::get(ThisPtr), ThisType);
// Add the rest of the parameters.
for (auto Param : MD->params())
EmitDelegateCallArg(CallArgs, Param, Param->getLocStart());
Implement conversion to function pointer for generic lambdas without captures. The general strategy is to create template versions of the conversion function and static invoker and then during template argument deduction of the conversion function, create the corresponding call-operator and static invoker specializations, and when the conversion function is marked referenced generate the body of the conversion function using the corresponding static-invoker specialization. Similarly, Codegen does something similar - when asked to emit the IR for a specialized static invoker of a generic lambda, it forwards emission to the corresponding call operator. This patch has been reviewed in person both by Doug and Richard. Richard gave me the LGTM. A few minor changes: - per Richard's request i added a simple check to gracefully inform that captures (init, explicit or default) have not been added to generic lambdas just yet (instead of the assertion violation). - I removed a few lines of code that added the call operators instantiated parameters to the currentinstantiationscope. Not only did it not handle parameter packs, but it is more relevant in the patch for nested lambdas which will follow this one, and fix that problem more comprehensively. - Doug had commented that the original implementation strategy of using the TypeSourceInfo of the call operator to create the static-invoker was flawed and allowed const as a member qualifier to creep into the type of the static-invoker. I currently kludge around it - but after my initial discussion with Doug, with a follow up session with Richard, I have added a FIXME so that a more elegant solution that involves the use of TrivialTypeSourceInfo call followed by the correct wiring of the template parameters to the functionprototypeloc is forthcoming. Thanks! llvm-svn: 191634
2013-09-29 16:45:24 +08:00
const CXXMethodDecl *CallOp = Lambda->getLambdaCallOperator();
// For a generic lambda, find the corresponding call operator specialization
// to which the call to the static-invoker shall be forwarded.
if (Lambda->isGenericLambda()) {
assert(MD->isFunctionTemplateSpecialization());
const TemplateArgumentList *TAL = MD->getTemplateSpecializationArgs();
FunctionTemplateDecl *CallOpTemplate = CallOp->getDescribedFunctionTemplate();
void *InsertPos = nullptr;
Implement conversion to function pointer for generic lambdas without captures. The general strategy is to create template versions of the conversion function and static invoker and then during template argument deduction of the conversion function, create the corresponding call-operator and static invoker specializations, and when the conversion function is marked referenced generate the body of the conversion function using the corresponding static-invoker specialization. Similarly, Codegen does something similar - when asked to emit the IR for a specialized static invoker of a generic lambda, it forwards emission to the corresponding call operator. This patch has been reviewed in person both by Doug and Richard. Richard gave me the LGTM. A few minor changes: - per Richard's request i added a simple check to gracefully inform that captures (init, explicit or default) have not been added to generic lambdas just yet (instead of the assertion violation). - I removed a few lines of code that added the call operators instantiated parameters to the currentinstantiationscope. Not only did it not handle parameter packs, but it is more relevant in the patch for nested lambdas which will follow this one, and fix that problem more comprehensively. - Doug had commented that the original implementation strategy of using the TypeSourceInfo of the call operator to create the static-invoker was flawed and allowed const as a member qualifier to creep into the type of the static-invoker. I currently kludge around it - but after my initial discussion with Doug, with a follow up session with Richard, I have added a FIXME so that a more elegant solution that involves the use of TrivialTypeSourceInfo call followed by the correct wiring of the template parameters to the functionprototypeloc is forthcoming. Thanks! llvm-svn: 191634
2013-09-29 16:45:24 +08:00
FunctionDecl *CorrespondingCallOpSpecialization =
CallOpTemplate->findSpecialization(TAL->asArray(), InsertPos);
Implement conversion to function pointer for generic lambdas without captures. The general strategy is to create template versions of the conversion function and static invoker and then during template argument deduction of the conversion function, create the corresponding call-operator and static invoker specializations, and when the conversion function is marked referenced generate the body of the conversion function using the corresponding static-invoker specialization. Similarly, Codegen does something similar - when asked to emit the IR for a specialized static invoker of a generic lambda, it forwards emission to the corresponding call operator. This patch has been reviewed in person both by Doug and Richard. Richard gave me the LGTM. A few minor changes: - per Richard's request i added a simple check to gracefully inform that captures (init, explicit or default) have not been added to generic lambdas just yet (instead of the assertion violation). - I removed a few lines of code that added the call operators instantiated parameters to the currentinstantiationscope. Not only did it not handle parameter packs, but it is more relevant in the patch for nested lambdas which will follow this one, and fix that problem more comprehensively. - Doug had commented that the original implementation strategy of using the TypeSourceInfo of the call operator to create the static-invoker was flawed and allowed const as a member qualifier to creep into the type of the static-invoker. I currently kludge around it - but after my initial discussion with Doug, with a follow up session with Richard, I have added a FIXME so that a more elegant solution that involves the use of TrivialTypeSourceInfo call followed by the correct wiring of the template parameters to the functionprototypeloc is forthcoming. Thanks! llvm-svn: 191634
2013-09-29 16:45:24 +08:00
assert(CorrespondingCallOpSpecialization);
CallOp = cast<CXXMethodDecl>(CorrespondingCallOpSpecialization);
}
EmitForwardingCallToLambda(CallOp, CallArgs);
}
void CodeGenFunction::EmitLambdaStaticInvokeFunction(const CXXMethodDecl *MD) {
if (MD->isVariadic()) {
// FIXME: Making this work correctly is nasty because it requires either
// cloning the body of the call operator or making the call operator forward.
CGM.ErrorUnsupported(MD, "lambda conversion to variadic function");
return;
}
EmitLambdaDelegatingInvokeBody(MD);
}