| //===--- CGAtomic.cpp - Emit LLVM IR for atomic operations ----------------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file contains the code for emitting atomic operations. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "CGCall.h" |
| #include "CGRecordLayout.h" |
| #include "CodeGenFunction.h" |
| #include "CodeGenModule.h" |
| #include "TargetInfo.h" |
| #include "clang/AST/ASTContext.h" |
| #include "clang/CodeGen/CGFunctionInfo.h" |
| #include "clang/Frontend/FrontendDiagnostic.h" |
| #include "llvm/ADT/DenseMap.h" |
| #include "llvm/IR/DataLayout.h" |
| #include "llvm/IR/Intrinsics.h" |
| #include "llvm/IR/Operator.h" |
| |
| using namespace clang; |
| using namespace CodeGen; |
| |
| namespace { |
| class AtomicInfo { |
| CodeGenFunction &CGF; |
| QualType AtomicTy; |
| QualType ValueTy; |
| uint64_t AtomicSizeInBits; |
| uint64_t ValueSizeInBits; |
| CharUnits AtomicAlign; |
| CharUnits ValueAlign; |
| TypeEvaluationKind EvaluationKind; |
| bool UseLibcall; |
| LValue LVal; |
| CGBitFieldInfo BFI; |
| public: |
| AtomicInfo(CodeGenFunction &CGF, LValue &lvalue) |
| : CGF(CGF), AtomicSizeInBits(0), ValueSizeInBits(0), |
| EvaluationKind(TEK_Scalar), UseLibcall(true) { |
| assert(!lvalue.isGlobalReg()); |
| ASTContext &C = CGF.getContext(); |
| if (lvalue.isSimple()) { |
| AtomicTy = lvalue.getType(); |
| if (auto *ATy = AtomicTy->getAs<AtomicType>()) |
| ValueTy = ATy->getValueType(); |
| else |
| ValueTy = AtomicTy; |
| EvaluationKind = CGF.getEvaluationKind(ValueTy); |
| |
| uint64_t ValueAlignInBits; |
| uint64_t AtomicAlignInBits; |
| TypeInfo ValueTI = C.getTypeInfo(ValueTy); |
| ValueSizeInBits = ValueTI.Width; |
| ValueAlignInBits = ValueTI.Align; |
| |
| TypeInfo AtomicTI = C.getTypeInfo(AtomicTy); |
| AtomicSizeInBits = AtomicTI.Width; |
| AtomicAlignInBits = AtomicTI.Align; |
| |
| assert(ValueSizeInBits <= AtomicSizeInBits); |
| assert(ValueAlignInBits <= AtomicAlignInBits); |
| |
| AtomicAlign = C.toCharUnitsFromBits(AtomicAlignInBits); |
| ValueAlign = C.toCharUnitsFromBits(ValueAlignInBits); |
| if (lvalue.getAlignment().isZero()) |
| lvalue.setAlignment(AtomicAlign); |
| |
| LVal = lvalue; |
| } else if (lvalue.isBitField()) { |
| ValueTy = lvalue.getType(); |
| ValueSizeInBits = C.getTypeSize(ValueTy); |
| auto &OrigBFI = lvalue.getBitFieldInfo(); |
| auto Offset = OrigBFI.Offset % C.toBits(lvalue.getAlignment()); |
| AtomicSizeInBits = C.toBits( |
| C.toCharUnitsFromBits(Offset + OrigBFI.Size + C.getCharWidth() - 1) |
| .alignTo(lvalue.getAlignment())); |
| auto VoidPtrAddr = CGF.EmitCastToVoidPtr(lvalue.getBitFieldPointer()); |
| auto OffsetInChars = |
| (C.toCharUnitsFromBits(OrigBFI.Offset) / lvalue.getAlignment()) * |
| lvalue.getAlignment(); |
| VoidPtrAddr = CGF.Builder.CreateConstGEP1_64( |
| VoidPtrAddr, OffsetInChars.getQuantity()); |
| auto Addr = CGF.Builder.CreatePointerBitCastOrAddrSpaceCast( |
| VoidPtrAddr, |
| CGF.Builder.getIntNTy(AtomicSizeInBits)->getPointerTo(), |
| "atomic_bitfield_base"); |
| BFI = OrigBFI; |
| BFI.Offset = Offset; |
| BFI.StorageSize = AtomicSizeInBits; |
| BFI.StorageOffset += OffsetInChars; |
| LVal = LValue::MakeBitfield(Address(Addr, lvalue.getAlignment()), |
| BFI, lvalue.getType(), lvalue.getBaseInfo(), |
| lvalue.getTBAAInfo()); |
| AtomicTy = C.getIntTypeForBitwidth(AtomicSizeInBits, OrigBFI.IsSigned); |
| if (AtomicTy.isNull()) { |
| llvm::APInt Size( |
| /*numBits=*/32, |
| C.toCharUnitsFromBits(AtomicSizeInBits).getQuantity()); |
| AtomicTy = |
| C.getConstantArrayType(C.CharTy, Size, nullptr, ArrayType::Normal, |
| /*IndexTypeQuals=*/0); |
| } |
| AtomicAlign = ValueAlign = lvalue.getAlignment(); |
| } else if (lvalue.isVectorElt()) { |
| ValueTy = lvalue.getType()->castAs<VectorType>()->getElementType(); |
| ValueSizeInBits = C.getTypeSize(ValueTy); |
| AtomicTy = lvalue.getType(); |
| AtomicSizeInBits = C.getTypeSize(AtomicTy); |
| AtomicAlign = ValueAlign = lvalue.getAlignment(); |
| LVal = lvalue; |
| } else { |
| assert(lvalue.isExtVectorElt()); |
| ValueTy = lvalue.getType(); |
| ValueSizeInBits = C.getTypeSize(ValueTy); |
| AtomicTy = ValueTy = CGF.getContext().getExtVectorType( |
| lvalue.getType(), cast<llvm::FixedVectorType>( |
| lvalue.getExtVectorAddress().getElementType()) |
| ->getNumElements()); |
| AtomicSizeInBits = C.getTypeSize(AtomicTy); |
| AtomicAlign = ValueAlign = lvalue.getAlignment(); |
| LVal = lvalue; |
| } |
| UseLibcall = !C.getTargetInfo().hasBuiltinAtomic( |
| AtomicSizeInBits, C.toBits(lvalue.getAlignment())); |
| } |
| |
| QualType getAtomicType() const { return AtomicTy; } |
| QualType getValueType() const { return ValueTy; } |
| CharUnits getAtomicAlignment() const { return AtomicAlign; } |
| uint64_t getAtomicSizeInBits() const { return AtomicSizeInBits; } |
| uint64_t getValueSizeInBits() const { return ValueSizeInBits; } |
| TypeEvaluationKind getEvaluationKind() const { return EvaluationKind; } |
| bool shouldUseLibcall() const { return UseLibcall; } |
| const LValue &getAtomicLValue() const { return LVal; } |
| llvm::Value *getAtomicPointer() const { |
| if (LVal.isSimple()) |
| return LVal.getPointer(CGF); |
| else if (LVal.isBitField()) |
| return LVal.getBitFieldPointer(); |
| else if (LVal.isVectorElt()) |
| return LVal.getVectorPointer(); |
| assert(LVal.isExtVectorElt()); |
| return LVal.getExtVectorPointer(); |
| } |
| Address getAtomicAddress() const { |
| return Address(getAtomicPointer(), getAtomicAlignment()); |
| } |
| |
| Address getAtomicAddressAsAtomicIntPointer() const { |
| return emitCastToAtomicIntPointer(getAtomicAddress()); |
| } |
| |
| /// Is the atomic size larger than the underlying value type? |
| /// |
| /// Note that the absence of padding does not mean that atomic |
| /// objects are completely interchangeable with non-atomic |
| /// objects: we might have promoted the alignment of a type |
| /// without making it bigger. |
| bool hasPadding() const { |
| return (ValueSizeInBits != AtomicSizeInBits); |
| } |
| |
| bool emitMemSetZeroIfNecessary() const; |
| |
| llvm::Value *getAtomicSizeValue() const { |
| CharUnits size = CGF.getContext().toCharUnitsFromBits(AtomicSizeInBits); |
| return CGF.CGM.getSize(size); |
| } |
| |
| /// Cast the given pointer to an integer pointer suitable for atomic |
| /// operations if the source. |
| Address emitCastToAtomicIntPointer(Address Addr) const; |
| |
| /// If Addr is compatible with the iN that will be used for an atomic |
| /// operation, bitcast it. Otherwise, create a temporary that is suitable |
| /// and copy the value across. |
| Address convertToAtomicIntPointer(Address Addr) const; |
| |
| /// Turn an atomic-layout object into an r-value. |
| RValue convertAtomicTempToRValue(Address addr, AggValueSlot resultSlot, |
| SourceLocation loc, bool AsValue) const; |
| |
| /// Converts a rvalue to integer value. |
| llvm::Value *convertRValueToInt(RValue RVal) const; |
| |
| RValue ConvertIntToValueOrAtomic(llvm::Value *IntVal, |
| AggValueSlot ResultSlot, |
| SourceLocation Loc, bool AsValue) const; |
| |
| /// Copy an atomic r-value into atomic-layout memory. |
| void emitCopyIntoMemory(RValue rvalue) const; |
| |
| /// Project an l-value down to the value field. |
| LValue projectValue() const { |
| assert(LVal.isSimple()); |
| Address addr = getAtomicAddress(); |
| if (hasPadding()) |
| addr = CGF.Builder.CreateStructGEP(addr, 0); |
| |
| return LValue::MakeAddr(addr, getValueType(), CGF.getContext(), |
| LVal.getBaseInfo(), LVal.getTBAAInfo()); |
| } |
| |
| /// Emits atomic load. |
| /// \returns Loaded value. |
| RValue EmitAtomicLoad(AggValueSlot ResultSlot, SourceLocation Loc, |
| bool AsValue, llvm::AtomicOrdering AO, |
| bool IsVolatile); |
| |
| /// Emits atomic compare-and-exchange sequence. |
| /// \param Expected Expected value. |
| /// \param Desired Desired value. |
| /// \param Success Atomic ordering for success operation. |
| /// \param Failure Atomic ordering for failed operation. |
| /// \param IsWeak true if atomic operation is weak, false otherwise. |
| /// \returns Pair of values: previous value from storage (value type) and |
| /// boolean flag (i1 type) with true if success and false otherwise. |
| std::pair<RValue, llvm::Value *> |
| EmitAtomicCompareExchange(RValue Expected, RValue Desired, |
| llvm::AtomicOrdering Success = |
| llvm::AtomicOrdering::SequentiallyConsistent, |
| llvm::AtomicOrdering Failure = |
| llvm::AtomicOrdering::SequentiallyConsistent, |
| bool IsWeak = false); |
| |
| /// Emits atomic update. |
| /// \param AO Atomic ordering. |
| /// \param UpdateOp Update operation for the current lvalue. |
| void EmitAtomicUpdate(llvm::AtomicOrdering AO, |
| const llvm::function_ref<RValue(RValue)> &UpdateOp, |
| bool IsVolatile); |
| /// Emits atomic update. |
| /// \param AO Atomic ordering. |
| void EmitAtomicUpdate(llvm::AtomicOrdering AO, RValue UpdateRVal, |
| bool IsVolatile); |
| |
| /// Materialize an atomic r-value in atomic-layout memory. |
| Address materializeRValue(RValue rvalue) const; |
| |
| /// Creates temp alloca for intermediate operations on atomic value. |
| Address CreateTempAlloca() const; |
| private: |
| bool requiresMemSetZero(llvm::Type *type) const; |
| |
| |
| /// Emits atomic load as a libcall. |
| void EmitAtomicLoadLibcall(llvm::Value *AddForLoaded, |
| llvm::AtomicOrdering AO, bool IsVolatile); |
| /// Emits atomic load as LLVM instruction. |
| llvm::Value *EmitAtomicLoadOp(llvm::AtomicOrdering AO, bool IsVolatile); |
| /// Emits atomic compare-and-exchange op as a libcall. |
| llvm::Value *EmitAtomicCompareExchangeLibcall( |
| llvm::Value *ExpectedAddr, llvm::Value *DesiredAddr, |
| llvm::AtomicOrdering Success = |
| llvm::AtomicOrdering::SequentiallyConsistent, |
| llvm::AtomicOrdering Failure = |
| llvm::AtomicOrdering::SequentiallyConsistent); |
| /// Emits atomic compare-and-exchange op as LLVM instruction. |
| std::pair<llvm::Value *, llvm::Value *> EmitAtomicCompareExchangeOp( |
| llvm::Value *ExpectedVal, llvm::Value *DesiredVal, |
| llvm::AtomicOrdering Success = |
| llvm::AtomicOrdering::SequentiallyConsistent, |
| llvm::AtomicOrdering Failure = |
| llvm::AtomicOrdering::SequentiallyConsistent, |
| bool IsWeak = false); |
| /// Emit atomic update as libcalls. |
| void |
| EmitAtomicUpdateLibcall(llvm::AtomicOrdering AO, |
| const llvm::function_ref<RValue(RValue)> &UpdateOp, |
| bool IsVolatile); |
| /// Emit atomic update as LLVM instructions. |
| void EmitAtomicUpdateOp(llvm::AtomicOrdering AO, |
| const llvm::function_ref<RValue(RValue)> &UpdateOp, |
| bool IsVolatile); |
| /// Emit atomic update as libcalls. |
| void EmitAtomicUpdateLibcall(llvm::AtomicOrdering AO, RValue UpdateRVal, |
| bool IsVolatile); |
| /// Emit atomic update as LLVM instructions. |
| void EmitAtomicUpdateOp(llvm::AtomicOrdering AO, RValue UpdateRal, |
| bool IsVolatile); |
| }; |
| } |
| |
| Address AtomicInfo::CreateTempAlloca() const { |
| Address TempAlloca = CGF.CreateMemTemp( |
| (LVal.isBitField() && ValueSizeInBits > AtomicSizeInBits) ? ValueTy |
| : AtomicTy, |
| getAtomicAlignment(), |
| "atomic-temp"); |
| // Cast to pointer to value type for bitfields. |
| if (LVal.isBitField()) |
| return CGF.Builder.CreatePointerBitCastOrAddrSpaceCast( |
| TempAlloca, getAtomicAddress().getType()); |
| return TempAlloca; |
| } |
| |
| static RValue emitAtomicLibcall(CodeGenFunction &CGF, |
| StringRef fnName, |
| QualType resultType, |
| CallArgList &args) { |
| const CGFunctionInfo &fnInfo = |
| CGF.CGM.getTypes().arrangeBuiltinFunctionCall(resultType, args); |
| llvm::FunctionType *fnTy = CGF.CGM.getTypes().GetFunctionType(fnInfo); |
| llvm::AttrBuilder fnAttrB; |
| fnAttrB.addAttribute(llvm::Attribute::NoUnwind); |
| fnAttrB.addAttribute(llvm::Attribute::WillReturn); |
| llvm::AttributeList fnAttrs = llvm::AttributeList::get( |
| CGF.getLLVMContext(), llvm::AttributeList::FunctionIndex, fnAttrB); |
| |
| llvm::FunctionCallee fn = |
| CGF.CGM.CreateRuntimeFunction(fnTy, fnName, fnAttrs); |
| auto callee = CGCallee::forDirect(fn); |
| return CGF.EmitCall(fnInfo, callee, ReturnValueSlot(), args); |
| } |
| |
| /// Does a store of the given IR type modify the full expected width? |
| static bool isFullSizeType(CodeGenModule &CGM, llvm::Type *type, |
| uint64_t expectedSize) { |
| return (CGM.getDataLayout().getTypeStoreSize(type) * 8 == expectedSize); |
| } |
| |
| /// Does the atomic type require memsetting to zero before initialization? |
| /// |
| /// The IR type is provided as a way of making certain queries faster. |
| bool AtomicInfo::requiresMemSetZero(llvm::Type *type) const { |
| // If the atomic type has size padding, we definitely need a memset. |
| if (hasPadding()) return true; |
| |
| // Otherwise, do some simple heuristics to try to avoid it: |
| switch (getEvaluationKind()) { |
| // For scalars and complexes, check whether the store size of the |
| // type uses the full size. |
| case TEK_Scalar: |
| return !isFullSizeType(CGF.CGM, type, AtomicSizeInBits); |
| case TEK_Complex: |
| return !isFullSizeType(CGF.CGM, type->getStructElementType(0), |
| AtomicSizeInBits / 2); |
| |
| // Padding in structs has an undefined bit pattern. User beware. |
| case TEK_Aggregate: |
| return false; |
| } |
| llvm_unreachable("bad evaluation kind"); |
| } |
| |
| bool AtomicInfo::emitMemSetZeroIfNecessary() const { |
| assert(LVal.isSimple()); |
| llvm::Value *addr = LVal.getPointer(CGF); |
| if (!requiresMemSetZero(addr->getType()->getPointerElementType())) |
| return false; |
| |
| CGF.Builder.CreateMemSet( |
| addr, llvm::ConstantInt::get(CGF.Int8Ty, 0), |
| CGF.getContext().toCharUnitsFromBits(AtomicSizeInBits).getQuantity(), |
| LVal.getAlignment().getAsAlign()); |
| return true; |
| } |
| |
| static void emitAtomicCmpXchg(CodeGenFunction &CGF, AtomicExpr *E, bool IsWeak, |
| Address Dest, Address Ptr, |
| Address Val1, Address Val2, |
| uint64_t Size, |
| llvm::AtomicOrdering SuccessOrder, |
| llvm::AtomicOrdering FailureOrder, |
| llvm::SyncScope::ID Scope) { |
| // Note that cmpxchg doesn't support weak cmpxchg, at least at the moment. |
| llvm::Value *Expected = CGF.Builder.CreateLoad(Val1); |
| llvm::Value *Desired = CGF.Builder.CreateLoad(Val2); |
| |
| llvm::AtomicCmpXchgInst *Pair = CGF.Builder.CreateAtomicCmpXchg( |
| Ptr.getPointer(), Expected, Desired, SuccessOrder, FailureOrder, |
| Scope); |
| Pair->setVolatile(E->isVolatile()); |
| Pair->setWeak(IsWeak); |
| |
| // Cmp holds the result of the compare-exchange operation: true on success, |
| // false on failure. |
| llvm::Value *Old = CGF.Builder.CreateExtractValue(Pair, 0); |
| llvm::Value *Cmp = CGF.Builder.CreateExtractValue(Pair, 1); |
| |
| // This basic block is used to hold the store instruction if the operation |
| // failed. |
| llvm::BasicBlock *StoreExpectedBB = |
| CGF.createBasicBlock("cmpxchg.store_expected", CGF.CurFn); |
| |
| // This basic block is the exit point of the operation, we should end up |
| // here regardless of whether or not the operation succeeded. |
| llvm::BasicBlock *ContinueBB = |
| CGF.createBasicBlock("cmpxchg.continue", CGF.CurFn); |
| |
| // Update Expected if Expected isn't equal to Old, otherwise branch to the |
| // exit point. |
| CGF.Builder.CreateCondBr(Cmp, ContinueBB, StoreExpectedBB); |
| |
| CGF.Builder.SetInsertPoint(StoreExpectedBB); |
| // Update the memory at Expected with Old's value. |
| CGF.Builder.CreateStore(Old, Val1); |
| // Finally, branch to the exit point. |
| CGF.Builder.CreateBr(ContinueBB); |
| |
| CGF.Builder.SetInsertPoint(ContinueBB); |
| // Update the memory at Dest with Cmp's value. |
| CGF.EmitStoreOfScalar(Cmp, CGF.MakeAddrLValue(Dest, E->getType())); |
| } |
| |
| /// Given an ordering required on success, emit all possible cmpxchg |
| /// instructions to cope with the provided (but possibly only dynamically known) |
| /// FailureOrder. |
| static void emitAtomicCmpXchgFailureSet(CodeGenFunction &CGF, AtomicExpr *E, |
| bool IsWeak, Address Dest, Address Ptr, |
| Address Val1, Address Val2, |
| llvm::Value *FailureOrderVal, |
| uint64_t Size, |
| llvm::AtomicOrdering SuccessOrder, |
| llvm::SyncScope::ID Scope) { |
| llvm::AtomicOrdering FailureOrder; |
| if (llvm::ConstantInt *FO = dyn_cast<llvm::ConstantInt>(FailureOrderVal)) { |
| auto FOS = FO->getSExtValue(); |
| if (!llvm::isValidAtomicOrderingCABI(FOS)) |
| FailureOrder = llvm::AtomicOrdering::Monotonic; |
| else |
| switch ((llvm::AtomicOrderingCABI)FOS) { |
| case llvm::AtomicOrderingCABI::relaxed: |
| case llvm::AtomicOrderingCABI::release: |
| case llvm::AtomicOrderingCABI::acq_rel: |
| FailureOrder = llvm::AtomicOrdering::Monotonic; |
| break; |
| case llvm::AtomicOrderingCABI::consume: |
| case llvm::AtomicOrderingCABI::acquire: |
| FailureOrder = llvm::AtomicOrdering::Acquire; |
| break; |
| case llvm::AtomicOrderingCABI::seq_cst: |
| FailureOrder = llvm::AtomicOrdering::SequentiallyConsistent; |
| break; |
| } |
| if (isStrongerThan(FailureOrder, SuccessOrder)) { |
| // Don't assert on undefined behavior "failure argument shall be no |
| // stronger than the success argument". |
| FailureOrder = |
| llvm::AtomicCmpXchgInst::getStrongestFailureOrdering(SuccessOrder); |
| } |
| emitAtomicCmpXchg(CGF, E, IsWeak, Dest, Ptr, Val1, Val2, Size, SuccessOrder, |
| FailureOrder, Scope); |
| return; |
| } |
| |
| // Create all the relevant BB's |
| llvm::BasicBlock *MonotonicBB = nullptr, *AcquireBB = nullptr, |
| *SeqCstBB = nullptr; |
| MonotonicBB = CGF.createBasicBlock("monotonic_fail", CGF.CurFn); |
| if (SuccessOrder != llvm::AtomicOrdering::Monotonic && |
| SuccessOrder != llvm::AtomicOrdering::Release) |
| AcquireBB = CGF.createBasicBlock("acquire_fail", CGF.CurFn); |
| if (SuccessOrder == llvm::AtomicOrdering::SequentiallyConsistent) |
| SeqCstBB = CGF.createBasicBlock("seqcst_fail", CGF.CurFn); |
| |
| llvm::BasicBlock *ContBB = CGF.createBasicBlock("atomic.continue", CGF.CurFn); |
| |
| llvm::SwitchInst *SI = CGF.Builder.CreateSwitch(FailureOrderVal, MonotonicBB); |
| |
| // Emit all the different atomics |
| |
| // MonotonicBB is arbitrarily chosen as the default case; in practice, this |
| // doesn't matter unless someone is crazy enough to use something that |
| // doesn't fold to a constant for the ordering. |
| CGF.Builder.SetInsertPoint(MonotonicBB); |
| emitAtomicCmpXchg(CGF, E, IsWeak, Dest, Ptr, Val1, Val2, |
| Size, SuccessOrder, llvm::AtomicOrdering::Monotonic, Scope); |
| CGF.Builder.CreateBr(ContBB); |
| |
| if (AcquireBB) { |
| CGF.Builder.SetInsertPoint(AcquireBB); |
| emitAtomicCmpXchg(CGF, E, IsWeak, Dest, Ptr, Val1, Val2, |
| Size, SuccessOrder, llvm::AtomicOrdering::Acquire, Scope); |
| CGF.Builder.CreateBr(ContBB); |
| SI->addCase(CGF.Builder.getInt32((int)llvm::AtomicOrderingCABI::consume), |
| AcquireBB); |
| SI->addCase(CGF.Builder.getInt32((int)llvm::AtomicOrderingCABI::acquire), |
| AcquireBB); |
| } |
| if (SeqCstBB) { |
| CGF.Builder.SetInsertPoint(SeqCstBB); |
| emitAtomicCmpXchg(CGF, E, IsWeak, Dest, Ptr, Val1, Val2, Size, SuccessOrder, |
| llvm::AtomicOrdering::SequentiallyConsistent, Scope); |
| CGF.Builder.CreateBr(ContBB); |
| SI->addCase(CGF.Builder.getInt32((int)llvm::AtomicOrderingCABI::seq_cst), |
| SeqCstBB); |
| } |
| |
| CGF.Builder.SetInsertPoint(ContBB); |
| } |
| |
| /// Duplicate the atomic min/max operation in conventional IR for the builtin |
| /// variants that return the new rather than the original value. |
| static llvm::Value *EmitPostAtomicMinMax(CGBuilderTy &Builder, |
| AtomicExpr::AtomicOp Op, |
| bool IsSigned, |
| llvm::Value *OldVal, |
| llvm::Value *RHS) { |
| llvm::CmpInst::Predicate Pred; |
| switch (Op) { |
| default: |
| llvm_unreachable("Unexpected min/max operation"); |
| case AtomicExpr::AO__atomic_max_fetch: |
| Pred = IsSigned ? llvm::CmpInst::ICMP_SGT : llvm::CmpInst::ICMP_UGT; |
| break; |
| case AtomicExpr::AO__atomic_min_fetch: |
| Pred = IsSigned ? llvm::CmpInst::ICMP_SLT : llvm::CmpInst::ICMP_ULT; |
| break; |
| } |
| llvm::Value *Cmp = Builder.CreateICmp(Pred, OldVal, RHS, "tst"); |
| return Builder.CreateSelect(Cmp, OldVal, RHS, "newval"); |
| } |
| |
| static void EmitAtomicOp(CodeGenFunction &CGF, AtomicExpr *E, Address Dest, |
| Address Ptr, Address Val1, Address Val2, |
| llvm::Value *IsWeak, llvm::Value *FailureOrder, |
| uint64_t Size, llvm::AtomicOrdering Order, |
| llvm::SyncScope::ID Scope) { |
| llvm::AtomicRMWInst::BinOp Op = llvm::AtomicRMWInst::Add; |
| bool PostOpMinMax = false; |
| unsigned PostOp = 0; |
| |
| switch (E->getOp()) { |
| case AtomicExpr::AO__c11_atomic_init: |
| case AtomicExpr::AO__opencl_atomic_init: |
| llvm_unreachable("Already handled!"); |
| |
| case AtomicExpr::AO__c11_atomic_compare_exchange_strong: |
| case AtomicExpr::AO__opencl_atomic_compare_exchange_strong: |
| emitAtomicCmpXchgFailureSet(CGF, E, false, Dest, Ptr, Val1, Val2, |
| FailureOrder, Size, Order, Scope); |
| return; |
| case AtomicExpr::AO__c11_atomic_compare_exchange_weak: |
| case AtomicExpr::AO__opencl_atomic_compare_exchange_weak: |
| emitAtomicCmpXchgFailureSet(CGF, E, true, Dest, Ptr, Val1, Val2, |
| FailureOrder, Size, Order, Scope); |
| return; |
| case AtomicExpr::AO__atomic_compare_exchange: |
| case AtomicExpr::AO__atomic_compare_exchange_n: { |
| if (llvm::ConstantInt *IsWeakC = dyn_cast<llvm::ConstantInt>(IsWeak)) { |
| emitAtomicCmpXchgFailureSet(CGF, E, IsWeakC->getZExtValue(), Dest, Ptr, |
| Val1, Val2, FailureOrder, Size, Order, Scope); |
| } else { |
| // Create all the relevant BB's |
| llvm::BasicBlock *StrongBB = |
| CGF.createBasicBlock("cmpxchg.strong", CGF.CurFn); |
| llvm::BasicBlock *WeakBB = CGF.createBasicBlock("cmxchg.weak", CGF.CurFn); |
| llvm::BasicBlock *ContBB = |
| CGF.createBasicBlock("cmpxchg.continue", CGF.CurFn); |
| |
| llvm::SwitchInst *SI = CGF.Builder.CreateSwitch(IsWeak, WeakBB); |
| SI->addCase(CGF.Builder.getInt1(false), StrongBB); |
| |
| CGF.Builder.SetInsertPoint(StrongBB); |
| emitAtomicCmpXchgFailureSet(CGF, E, false, Dest, Ptr, Val1, Val2, |
| FailureOrder, Size, Order, Scope); |
| CGF.Builder.CreateBr(ContBB); |
| |
| CGF.Builder.SetInsertPoint(WeakBB); |
| emitAtomicCmpXchgFailureSet(CGF, E, true, Dest, Ptr, Val1, Val2, |
| FailureOrder, Size, Order, Scope); |
| CGF.Builder.CreateBr(ContBB); |
| |
| CGF.Builder.SetInsertPoint(ContBB); |
| } |
| return; |
| } |
| case AtomicExpr::AO__c11_atomic_load: |
| case AtomicExpr::AO__opencl_atomic_load: |
| case AtomicExpr::AO__atomic_load_n: |
| case AtomicExpr::AO__atomic_load: { |
| llvm::LoadInst *Load = CGF.Builder.CreateLoad(Ptr); |
| Load->setAtomic(Order, Scope); |
| Load->setVolatile(E->isVolatile()); |
| CGF.Builder.CreateStore(Load, Dest); |
| return; |
| } |
| |
| case AtomicExpr::AO__c11_atomic_store: |
| case AtomicExpr::AO__opencl_atomic_store: |
| case AtomicExpr::AO__atomic_store: |
| case AtomicExpr::AO__atomic_store_n: { |
| llvm::Value *LoadVal1 = CGF.Builder.CreateLoad(Val1); |
| llvm::StoreInst *Store = CGF.Builder.CreateStore(LoadVal1, Ptr); |
| Store->setAtomic(Order, Scope); |
| Store->setVolatile(E->isVolatile()); |
| return; |
| } |
| |
| case AtomicExpr::AO__c11_atomic_exchange: |
| case AtomicExpr::AO__opencl_atomic_exchange: |
| case AtomicExpr::AO__atomic_exchange_n: |
| case AtomicExpr::AO__atomic_exchange: |
| Op = llvm::AtomicRMWInst::Xchg; |
| break; |
| |
| case AtomicExpr::AO__atomic_add_fetch: |
| PostOp = llvm::Instruction::Add; |
| LLVM_FALLTHROUGH; |
| case AtomicExpr::AO__c11_atomic_fetch_add: |
| case AtomicExpr::AO__opencl_atomic_fetch_add: |
| case AtomicExpr::AO__atomic_fetch_add: |
| Op = llvm::AtomicRMWInst::Add; |
| break; |
| |
| case AtomicExpr::AO__atomic_sub_fetch: |
| PostOp = llvm::Instruction::Sub; |
| LLVM_FALLTHROUGH; |
| case AtomicExpr::AO__c11_atomic_fetch_sub: |
| case AtomicExpr::AO__opencl_atomic_fetch_sub: |
| case AtomicExpr::AO__atomic_fetch_sub: |
| Op = llvm::AtomicRMWInst::Sub; |
| break; |
| |
| case AtomicExpr::AO__atomic_min_fetch: |
| PostOpMinMax = true; |
| LLVM_FALLTHROUGH; |
| case AtomicExpr::AO__c11_atomic_fetch_min: |
| case AtomicExpr::AO__opencl_atomic_fetch_min: |
| case AtomicExpr::AO__atomic_fetch_min: |
| Op = E->getValueType()->isSignedIntegerType() ? llvm::AtomicRMWInst::Min |
| : llvm::AtomicRMWInst::UMin; |
| break; |
| |
| case AtomicExpr::AO__atomic_max_fetch: |
| PostOpMinMax = true; |
| LLVM_FALLTHROUGH; |
| case AtomicExpr::AO__c11_atomic_fetch_max: |
| case AtomicExpr::AO__opencl_atomic_fetch_max: |
| case AtomicExpr::AO__atomic_fetch_max: |
| Op = E->getValueType()->isSignedIntegerType() ? llvm::AtomicRMWInst::Max |
| : llvm::AtomicRMWInst::UMax; |
| break; |
| |
| case AtomicExpr::AO__atomic_and_fetch: |
| PostOp = llvm::Instruction::And; |
| LLVM_FALLTHROUGH; |
| case AtomicExpr::AO__c11_atomic_fetch_and: |
| case AtomicExpr::AO__opencl_atomic_fetch_and: |
| case AtomicExpr::AO__atomic_fetch_and: |
| Op = llvm::AtomicRMWInst::And; |
| break; |
| |
| case AtomicExpr::AO__atomic_or_fetch: |
| PostOp = llvm::Instruction::Or; |
| LLVM_FALLTHROUGH; |
| case AtomicExpr::AO__c11_atomic_fetch_or: |
| case AtomicExpr::AO__opencl_atomic_fetch_or: |
| case AtomicExpr::AO__atomic_fetch_or: |
| Op = llvm::AtomicRMWInst::Or; |
| break; |
| |
| case AtomicExpr::AO__atomic_xor_fetch: |
| PostOp = llvm::Instruction::Xor; |
| LLVM_FALLTHROUGH; |
| case AtomicExpr::AO__c11_atomic_fetch_xor: |
| case AtomicExpr::AO__opencl_atomic_fetch_xor: |
| case AtomicExpr::AO__atomic_fetch_xor: |
| Op = llvm::AtomicRMWInst::Xor; |
| break; |
| |
| case AtomicExpr::AO__atomic_nand_fetch: |
| PostOp = llvm::Instruction::And; // the NOT is special cased below |
| LLVM_FALLTHROUGH; |
| case AtomicExpr::AO__atomic_fetch_nand: |
| Op = llvm::AtomicRMWInst::Nand; |
| break; |
| } |
| |
| llvm::Value *LoadVal1 = CGF.Builder.CreateLoad(Val1); |
| llvm::AtomicRMWInst *RMWI = |
| CGF.Builder.CreateAtomicRMW(Op, Ptr.getPointer(), LoadVal1, Order, Scope); |
| RMWI->setVolatile(E->isVolatile()); |
| |
| // For __atomic_*_fetch operations, perform the operation again to |
| // determine the value which was written. |
| llvm::Value *Result = RMWI; |
| if (PostOpMinMax) |
| Result = EmitPostAtomicMinMax(CGF.Builder, E->getOp(), |
| E->getValueType()->isSignedIntegerType(), |
| RMWI, LoadVal1); |
| else if (PostOp) |
| Result = CGF.Builder.CreateBinOp((llvm::Instruction::BinaryOps)PostOp, RMWI, |
| LoadVal1); |
| if (E->getOp() == AtomicExpr::AO__atomic_nand_fetch) |
| Result = CGF.Builder.CreateNot(Result); |
| CGF.Builder.CreateStore(Result, Dest); |
| } |
| |
| // This function emits any expression (scalar, complex, or aggregate) |
| // into a temporary alloca. |
| static Address |
| EmitValToTemp(CodeGenFunction &CGF, Expr *E) { |
| Address DeclPtr = CGF.CreateMemTemp(E->getType(), ".atomictmp"); |
| CGF.EmitAnyExprToMem(E, DeclPtr, E->getType().getQualifiers(), |
| /*Init*/ true); |
| return DeclPtr; |
| } |
| |
| static void EmitAtomicOp(CodeGenFunction &CGF, AtomicExpr *Expr, Address Dest, |
| Address Ptr, Address Val1, Address Val2, |
| llvm::Value *IsWeak, llvm::Value *FailureOrder, |
| uint64_t Size, llvm::AtomicOrdering Order, |
| llvm::Value *Scope) { |
| auto ScopeModel = Expr->getScopeModel(); |
| |
| // LLVM atomic instructions always have synch scope. If clang atomic |
| // expression has no scope operand, use default LLVM synch scope. |
| if (!ScopeModel) { |
| EmitAtomicOp(CGF, Expr, Dest, Ptr, Val1, Val2, IsWeak, FailureOrder, Size, |
| Order, CGF.CGM.getLLVMContext().getOrInsertSyncScopeID("")); |
| return; |
| } |
| |
| // Handle constant scope. |
| if (auto SC = dyn_cast<llvm::ConstantInt>(Scope)) { |
| auto SCID = CGF.getTargetHooks().getLLVMSyncScopeID( |
| CGF.CGM.getLangOpts(), ScopeModel->map(SC->getZExtValue()), |
| Order, CGF.CGM.getLLVMContext()); |
| EmitAtomicOp(CGF, Expr, Dest, Ptr, Val1, Val2, IsWeak, FailureOrder, Size, |
| Order, SCID); |
| return; |
| } |
| |
| // Handle non-constant scope. |
| auto &Builder = CGF.Builder; |
| auto Scopes = ScopeModel->getRuntimeValues(); |
| llvm::DenseMap<unsigned, llvm::BasicBlock *> BB; |
| for (auto S : Scopes) |
| BB[S] = CGF.createBasicBlock(getAsString(ScopeModel->map(S)), CGF.CurFn); |
| |
| llvm::BasicBlock *ContBB = |
| CGF.createBasicBlock("atomic.scope.continue", CGF.CurFn); |
| |
| auto *SC = Builder.CreateIntCast(Scope, Builder.getInt32Ty(), false); |
| // If unsupported synch scope is encountered at run time, assume a fallback |
| // synch scope value. |
| auto FallBack = ScopeModel->getFallBackValue(); |
| llvm::SwitchInst *SI = Builder.CreateSwitch(SC, BB[FallBack]); |
| for (auto S : Scopes) { |
| auto *B = BB[S]; |
| if (S != FallBack) |
| SI->addCase(Builder.getInt32(S), B); |
| |
| Builder.SetInsertPoint(B); |
| EmitAtomicOp(CGF, Expr, Dest, Ptr, Val1, Val2, IsWeak, FailureOrder, Size, |
| Order, |
| CGF.getTargetHooks().getLLVMSyncScopeID(CGF.CGM.getLangOpts(), |
| ScopeModel->map(S), |
| Order, |
| CGF.getLLVMContext())); |
| Builder.CreateBr(ContBB); |
| } |
| |
| Builder.SetInsertPoint(ContBB); |
| } |
| |
| static void |
| AddDirectArgument(CodeGenFunction &CGF, CallArgList &Args, |
| bool UseOptimizedLibcall, llvm::Value *Val, QualType ValTy, |
| SourceLocation Loc, CharUnits SizeInChars) { |
| if (UseOptimizedLibcall) { |
| // Load value and pass it to the function directly. |
| CharUnits Align = CGF.getContext().getTypeAlignInChars(ValTy); |
| int64_t SizeInBits = CGF.getContext().toBits(SizeInChars); |
| ValTy = |
| CGF.getContext().getIntTypeForBitwidth(SizeInBits, /*Signed=*/false); |
| llvm::Type *IPtrTy = llvm::IntegerType::get(CGF.getLLVMContext(), |
| SizeInBits)->getPointerTo(); |
| Address Ptr = Address(CGF.Builder.CreateBitCast(Val, IPtrTy), Align); |
| Val = CGF.EmitLoadOfScalar(Ptr, false, |
| CGF.getContext().getPointerType(ValTy), |
| Loc); |
| // Coerce the value into an appropriately sized integer type. |
| Args.add(RValue::get(Val), ValTy); |
| } else { |
| // Non-optimized functions always take a reference. |
| Args.add(RValue::get(CGF.EmitCastToVoidPtr(Val)), |
| CGF.getContext().VoidPtrTy); |
| } |
| } |
| |
| RValue CodeGenFunction::EmitAtomicExpr(AtomicExpr *E) { |
| QualType AtomicTy = E->getPtr()->getType()->getPointeeType(); |
| QualType MemTy = AtomicTy; |
| if (const AtomicType *AT = AtomicTy->getAs<AtomicType>()) |
| MemTy = AT->getValueType(); |
| llvm::Value *IsWeak = nullptr, *OrderFail = nullptr; |
| |
| Address Val1 = Address::invalid(); |
| Address Val2 = Address::invalid(); |
| Address Dest = Address::invalid(); |
| Address Ptr = EmitPointerWithAlignment(E->getPtr()); |
| |
| if (E->getOp() == AtomicExpr::AO__c11_atomic_init || |
| E->getOp() == AtomicExpr::AO__opencl_atomic_init) { |
| LValue lvalue = MakeAddrLValue(Ptr, AtomicTy); |
| EmitAtomicInit(E->getVal1(), lvalue); |
| return RValue::get(nullptr); |
| } |
| |
| CharUnits sizeChars, alignChars; |
| std::tie(sizeChars, alignChars) = getContext().getTypeInfoInChars(AtomicTy); |
| uint64_t Size = sizeChars.getQuantity(); |
| unsigned MaxInlineWidthInBits = getTarget().getMaxAtomicInlineWidth(); |
| |
| bool Oversized = getContext().toBits(sizeChars) > MaxInlineWidthInBits; |
| bool Misaligned = (Ptr.getAlignment() % sizeChars) != 0; |
| bool UseLibcall = Misaligned | Oversized; |
| CharUnits MaxInlineWidth = |
| getContext().toCharUnitsFromBits(MaxInlineWidthInBits); |
| |
| DiagnosticsEngine &Diags = CGM.getDiags(); |
| |
| if (Misaligned) { |
| Diags.Report(E->getBeginLoc(), diag::warn_atomic_op_misaligned) |
| << (int)sizeChars.getQuantity() |
| << (int)Ptr.getAlignment().getQuantity(); |
| } |
| |
| if (Oversized) { |
| Diags.Report(E->getBeginLoc(), diag::warn_atomic_op_oversized) |
| << (int)sizeChars.getQuantity() << (int)MaxInlineWidth.getQuantity(); |
| } |
| |
| llvm::Value *Order = EmitScalarExpr(E->getOrder()); |
| llvm::Value *Scope = |
| E->getScopeModel() ? EmitScalarExpr(E->getScope()) : nullptr; |
| |
| switch (E->getOp()) { |
| case AtomicExpr::AO__c11_atomic_init: |
| case AtomicExpr::AO__opencl_atomic_init: |
| llvm_unreachable("Already handled above with EmitAtomicInit!"); |
| |
| case AtomicExpr::AO__c11_atomic_load: |
| case AtomicExpr::AO__opencl_atomic_load: |
| case AtomicExpr::AO__atomic_load_n: |
| break; |
| |
| case AtomicExpr::AO__atomic_load: |
| Dest = EmitPointerWithAlignment(E->getVal1()); |
| break; |
| |
| case AtomicExpr::AO__atomic_store: |
| Val1 = EmitPointerWithAlignment(E->getVal1()); |
| break; |
| |
| case AtomicExpr::AO__atomic_exchange: |
| Val1 = EmitPointerWithAlignment(E->getVal1()); |
| Dest = EmitPointerWithAlignment(E->getVal2()); |
| break; |
| |
| case AtomicExpr::AO__c11_atomic_compare_exchange_strong: |
| case AtomicExpr::AO__c11_atomic_compare_exchange_weak: |
| case AtomicExpr::AO__opencl_atomic_compare_exchange_strong: |
| case AtomicExpr::AO__opencl_atomic_compare_exchange_weak: |
| case AtomicExpr::AO__atomic_compare_exchange_n: |
| case AtomicExpr::AO__atomic_compare_exchange: |
| Val1 = EmitPointerWithAlignment(E->getVal1()); |
| if (E->getOp() == AtomicExpr::AO__atomic_compare_exchange) |
| Val2 = EmitPointerWithAlignment(E->getVal2()); |
| else |
| Val2 = EmitValToTemp(*this, E->getVal2()); |
| OrderFail = EmitScalarExpr(E->getOrderFail()); |
| if (E->getOp() == AtomicExpr::AO__atomic_compare_exchange_n || |
| E->getOp() == AtomicExpr::AO__atomic_compare_exchange) |
| IsWeak = EmitScalarExpr(E->getWeak()); |
| break; |
| |
| case AtomicExpr::AO__c11_atomic_fetch_add: |
| case AtomicExpr::AO__c11_atomic_fetch_sub: |
| case AtomicExpr::AO__opencl_atomic_fetch_add: |
| case AtomicExpr::AO__opencl_atomic_fetch_sub: |
| if (MemTy->isPointerType()) { |
| // For pointer arithmetic, we're required to do a bit of math: |
| // adding 1 to an int* is not the same as adding 1 to a uintptr_t. |
| // ... but only for the C11 builtins. The GNU builtins expect the |
| // user to multiply by sizeof(T). |
| QualType Val1Ty = E->getVal1()->getType(); |
| llvm::Value *Val1Scalar = EmitScalarExpr(E->getVal1()); |
| CharUnits PointeeIncAmt = |
| getContext().getTypeSizeInChars(MemTy->getPointeeType()); |
| Val1Scalar = Builder.CreateMul(Val1Scalar, CGM.getSize(PointeeIncAmt)); |
| auto Temp = CreateMemTemp(Val1Ty, ".atomictmp"); |
| Val1 = Temp; |
| EmitStoreOfScalar(Val1Scalar, MakeAddrLValue(Temp, Val1Ty)); |
| break; |
| } |
| LLVM_FALLTHROUGH; |
| case AtomicExpr::AO__atomic_fetch_add: |
| case AtomicExpr::AO__atomic_fetch_sub: |
| case AtomicExpr::AO__atomic_add_fetch: |
| case AtomicExpr::AO__atomic_sub_fetch: |
| case AtomicExpr::AO__c11_atomic_store: |
| case AtomicExpr::AO__c11_atomic_exchange: |
| case AtomicExpr::AO__opencl_atomic_store: |
| case AtomicExpr::AO__opencl_atomic_exchange: |
| case AtomicExpr::AO__atomic_store_n: |
| case AtomicExpr::AO__atomic_exchange_n: |
| case AtomicExpr::AO__c11_atomic_fetch_and: |
| case AtomicExpr::AO__c11_atomic_fetch_or: |
| case AtomicExpr::AO__c11_atomic_fetch_xor: |
| case AtomicExpr::AO__c11_atomic_fetch_max: |
| case AtomicExpr::AO__c11_atomic_fetch_min: |
| case AtomicExpr::AO__opencl_atomic_fetch_and: |
| case AtomicExpr::AO__opencl_atomic_fetch_or: |
| case AtomicExpr::AO__opencl_atomic_fetch_xor: |
| case AtomicExpr::AO__opencl_atomic_fetch_min: |
| case AtomicExpr::AO__opencl_atomic_fetch_max: |
| case AtomicExpr::AO__atomic_fetch_and: |
| case AtomicExpr::AO__atomic_fetch_or: |
| case AtomicExpr::AO__atomic_fetch_xor: |
| case AtomicExpr::AO__atomic_fetch_nand: |
| case AtomicExpr::AO__atomic_and_fetch: |
| case AtomicExpr::AO__atomic_or_fetch: |
| case AtomicExpr::AO__atomic_xor_fetch: |
| case AtomicExpr::AO__atomic_nand_fetch: |
| case AtomicExpr::AO__atomic_max_fetch: |
| case AtomicExpr::AO__atomic_min_fetch: |
| case AtomicExpr::AO__atomic_fetch_max: |
| case AtomicExpr::AO__atomic_fetch_min: |
| Val1 = EmitValToTemp(*this, E->getVal1()); |
| break; |
| } |
| |
| QualType RValTy = E->getType().getUnqualifiedType(); |
| |
| // The inlined atomics only function on iN types, where N is a power of 2. We |
| // need to make sure (via temporaries if necessary) that all incoming values |
| // are compatible. |
| LValue AtomicVal = MakeAddrLValue(Ptr, AtomicTy); |
| AtomicInfo Atomics(*this, AtomicVal); |
| |
| Ptr = Atomics.emitCastToAtomicIntPointer(Ptr); |
| if (Val1.isValid()) Val1 = Atomics.convertToAtomicIntPointer(Val1); |
| if (Val2.isValid()) Val2 = Atomics.convertToAtomicIntPointer(Val2); |
| if (Dest.isValid()) |
| Dest = Atomics.emitCastToAtomicIntPointer(Dest); |
| else if (E->isCmpXChg()) |
| Dest = CreateMemTemp(RValTy, "cmpxchg.bool"); |
| else if (!RValTy->isVoidType()) |
| Dest = Atomics.emitCastToAtomicIntPointer(Atomics.CreateTempAlloca()); |
| |
| // Use a library call. See: http://gcc.gnu.org/wiki/Atomic/GCCMM/LIbrary . |
| if (UseLibcall) { |
| bool UseOptimizedLibcall = false; |
| switch (E->getOp()) { |
| case AtomicExpr::AO__c11_atomic_init: |
| case AtomicExpr::AO__opencl_atomic_init: |
| llvm_unreachable("Already handled above with EmitAtomicInit!"); |
| |
| case AtomicExpr::AO__c11_atomic_fetch_add: |
| case AtomicExpr::AO__opencl_atomic_fetch_add: |
| case AtomicExpr::AO__atomic_fetch_add: |
| case AtomicExpr::AO__c11_atomic_fetch_and: |
| case AtomicExpr::AO__opencl_atomic_fetch_and: |
| case AtomicExpr::AO__atomic_fetch_and: |
| case AtomicExpr::AO__c11_atomic_fetch_or: |
| case AtomicExpr::AO__opencl_atomic_fetch_or: |
| case AtomicExpr::AO__atomic_fetch_or: |
| case AtomicExpr::AO__atomic_fetch_nand: |
| case AtomicExpr::AO__c11_atomic_fetch_sub: |
| case AtomicExpr::AO__opencl_atomic_fetch_sub: |
| case AtomicExpr::AO__atomic_fetch_sub: |
| case AtomicExpr::AO__c11_atomic_fetch_xor: |
| case AtomicExpr::AO__opencl_atomic_fetch_xor: |
| case AtomicExpr::AO__opencl_atomic_fetch_min: |
| case AtomicExpr::AO__opencl_atomic_fetch_max: |
| case AtomicExpr::AO__atomic_fetch_xor: |
| case AtomicExpr::AO__c11_atomic_fetch_max: |
| case AtomicExpr::AO__c11_atomic_fetch_min: |
| case AtomicExpr::AO__atomic_add_fetch: |
| case AtomicExpr::AO__atomic_and_fetch: |
| case AtomicExpr::AO__atomic_nand_fetch: |
| case AtomicExpr::AO__atomic_or_fetch: |
| case AtomicExpr::AO__atomic_sub_fetch: |
| case AtomicExpr::AO__atomic_xor_fetch: |
| case AtomicExpr::AO__atomic_fetch_max: |
| case AtomicExpr::AO__atomic_fetch_min: |
| case AtomicExpr::AO__atomic_max_fetch: |
| case AtomicExpr::AO__atomic_min_fetch: |
| // For these, only library calls for certain sizes exist. |
| UseOptimizedLibcall = true; |
| break; |
| |
| case AtomicExpr::AO__atomic_load: |
| case AtomicExpr::AO__atomic_store: |
| case AtomicExpr::AO__atomic_exchange: |
| case AtomicExpr::AO__atomic_compare_exchange: |
| // Use the generic version if we don't know that the operand will be |
| // suitably aligned for the optimized version. |
| if (Misaligned) |
| break; |
| LLVM_FALLTHROUGH; |
| case AtomicExpr::AO__c11_atomic_load: |
| case AtomicExpr::AO__c11_atomic_store: |
| case AtomicExpr::AO__c11_atomic_exchange: |
| case AtomicExpr::AO__c11_atomic_compare_exchange_weak: |
| case AtomicExpr::AO__c11_atomic_compare_exchange_strong: |
| case AtomicExpr::AO__opencl_atomic_load: |
| case AtomicExpr::AO__opencl_atomic_store: |
| case AtomicExpr::AO__opencl_atomic_exchange: |
| case AtomicExpr::AO__opencl_atomic_compare_exchange_weak: |
| case AtomicExpr::AO__opencl_atomic_compare_exchange_strong: |
| case AtomicExpr::AO__atomic_load_n: |
| case AtomicExpr::AO__atomic_store_n: |
| case AtomicExpr::AO__atomic_exchange_n: |
| case AtomicExpr::AO__atomic_compare_exchange_n: |
| // Only use optimized library calls for sizes for which they exist. |
| // FIXME: Size == 16 optimized library functions exist too. |
| if (Size == 1 || Size == 2 || Size == 4 || Size == 8) |
| UseOptimizedLibcall = true; |
| break; |
| } |
| |
| CallArgList Args; |
| if (!UseOptimizedLibcall) { |
| // For non-optimized library calls, the size is the first parameter |
| Args.add(RValue::get(llvm::ConstantInt::get(SizeTy, Size)), |
| getContext().getSizeType()); |
| } |
| // Atomic address is the first or second parameter |
| // The OpenCL atomic library functions only accept pointer arguments to |
| // generic address space. |
| auto CastToGenericAddrSpace = [&](llvm::Value *V, QualType PT) { |
| if (!E->isOpenCL()) |
| return V; |
| auto AS = PT->castAs<PointerType>()->getPointeeType().getAddressSpace(); |
| if (AS == LangAS::opencl_generic) |
| return V; |
| auto DestAS = getContext().getTargetAddressSpace(LangAS::opencl_generic); |
| auto T = V->getType(); |
| auto *DestType = T->getPointerElementType()->getPointerTo(DestAS); |
| |
| return getTargetHooks().performAddrSpaceCast( |
| *this, V, AS, LangAS::opencl_generic, DestType, false); |
| }; |
| |
| Args.add(RValue::get(CastToGenericAddrSpace( |
| EmitCastToVoidPtr(Ptr.getPointer()), E->getPtr()->getType())), |
| getContext().VoidPtrTy); |
| |
| std::string LibCallName; |
| QualType LoweredMemTy = |
| MemTy->isPointerType() ? getContext().getIntPtrType() : MemTy; |
| QualType RetTy; |
| bool HaveRetTy = false; |
| llvm::Instruction::BinaryOps PostOp = (llvm::Instruction::BinaryOps)0; |
| bool PostOpMinMax = false; |
| switch (E->getOp()) { |
| case AtomicExpr::AO__c11_atomic_init: |
| case AtomicExpr::AO__opencl_atomic_init: |
| llvm_unreachable("Already handled!"); |
| |
| // There is only one libcall for compare an exchange, because there is no |
| // optimisation benefit possible from a libcall version of a weak compare |
| // and exchange. |
| // bool __atomic_compare_exchange(size_t size, void *mem, void *expected, |
| // void *desired, int success, int failure) |
| // bool __atomic_compare_exchange_N(T *mem, T *expected, T desired, |
| // int success, int failure) |
| case AtomicExpr::AO__c11_atomic_compare_exchange_weak: |
| case AtomicExpr::AO__c11_atomic_compare_exchange_strong: |
| case AtomicExpr::AO__opencl_atomic_compare_exchange_weak: |
| case AtomicExpr::AO__opencl_atomic_compare_exchange_strong: |
| case AtomicExpr::AO__atomic_compare_exchange: |
| case AtomicExpr::AO__atomic_compare_exchange_n: |
| LibCallName = "__atomic_compare_exchange"; |
| RetTy = getContext().BoolTy; |
| HaveRetTy = true; |
| Args.add( |
| RValue::get(CastToGenericAddrSpace( |
| EmitCastToVoidPtr(Val1.getPointer()), E->getVal1()->getType())), |
| getContext().VoidPtrTy); |
| AddDirectArgument(*this, Args, UseOptimizedLibcall, Val2.getPointer(), |
| MemTy, E->getExprLoc(), sizeChars); |
| Args.add(RValue::get(Order), getContext().IntTy); |
| Order = OrderFail; |
| break; |
| // void __atomic_exchange(size_t size, void *mem, void *val, void *return, |
| // int order) |
| // T __atomic_exchange_N(T *mem, T val, int order) |
| case AtomicExpr::AO__c11_atomic_exchange: |
| case AtomicExpr::AO__opencl_atomic_exchange: |
| case AtomicExpr::AO__atomic_exchange_n: |
| case AtomicExpr::AO__atomic_exchange: |
| LibCallName = "__atomic_exchange"; |
| AddDirectArgument(*this, Args, UseOptimizedLibcall, Val1.getPointer(), |
| MemTy, E->getExprLoc(), sizeChars); |
| break; |
| // void __atomic_store(size_t size, void *mem, void *val, int order) |
| // void __atomic_store_N(T *mem, T val, int order) |
| case AtomicExpr::AO__c11_atomic_store: |
| case AtomicExpr::AO__opencl_atomic_store: |
| case AtomicExpr::AO__atomic_store: |
| case AtomicExpr::AO__atomic_store_n: |
| LibCallName = "__atomic_store"; |
| RetTy = getContext().VoidTy; |
| HaveRetTy = true; |
| AddDirectArgument(*this, Args, UseOptimizedLibcall, Val1.getPointer(), |
| MemTy, E->getExprLoc(), sizeChars); |
| break; |
| // void __atomic_load(size_t size, void *mem, void *return, int order) |
| // T __atomic_load_N(T *mem, int order) |
| case AtomicExpr::AO__c11_atomic_load: |
| case AtomicExpr::AO__opencl_atomic_load: |
| case AtomicExpr::AO__atomic_load: |
| case AtomicExpr::AO__atomic_load_n: |
| LibCallName = "__atomic_load"; |
| break; |
| // T __atomic_add_fetch_N(T *mem, T val, int order) |
| // T __atomic_fetch_add_N(T *mem, T val, int order) |
| case AtomicExpr::AO__atomic_add_fetch: |
| PostOp = llvm::Instruction::Add; |
| LLVM_FALLTHROUGH; |
| case AtomicExpr::AO__c11_atomic_fetch_add: |
| case AtomicExpr::AO__opencl_atomic_fetch_add: |
| case AtomicExpr::AO__atomic_fetch_add: |
| LibCallName = "__atomic_fetch_add"; |
| AddDirectArgument(*this, Args, UseOptimizedLibcall, Val1.getPointer(), |
| LoweredMemTy, E->getExprLoc(), sizeChars); |
| break; |
| // T __atomic_and_fetch_N(T *mem, T val, int order) |
| // T __atomic_fetch_and_N(T *mem, T val, int order) |
| case AtomicExpr::AO__atomic_and_fetch: |
| PostOp = llvm::Instruction::And; |
| LLVM_FALLTHROUGH; |
| case AtomicExpr::AO__c11_atomic_fetch_and: |
| case AtomicExpr::AO__opencl_atomic_fetch_and: |
| case AtomicExpr::AO__atomic_fetch_and: |
| LibCallName = "__atomic_fetch_and"; |
| AddDirectArgument(*this, Args, UseOptimizedLibcall, Val1.getPointer(), |
| MemTy, E->getExprLoc(), sizeChars); |
| break; |
| // T __atomic_or_fetch_N(T *mem, T val, int order) |
| // T __atomic_fetch_or_N(T *mem, T val, int order) |
| case AtomicExpr::AO__atomic_or_fetch: |
| PostOp = llvm::Instruction::Or; |
| LLVM_FALLTHROUGH; |
| case AtomicExpr::AO__c11_atomic_fetch_or: |
| case AtomicExpr::AO__opencl_atomic_fetch_or: |
| case AtomicExpr::AO__atomic_fetch_or: |
| LibCallName = "__atomic_fetch_or"; |
| AddDirectArgument(*this, Args, UseOptimizedLibcall, Val1.getPointer(), |
| MemTy, E->getExprLoc(), sizeChars); |
| break; |
| // T __atomic_sub_fetch_N(T *mem, T val, int order) |
| // T __atomic_fetch_sub_N(T *mem, T val, int order) |
| case AtomicExpr::AO__atomic_sub_fetch: |
| PostOp = llvm::Instruction::Sub; |
| LLVM_FALLTHROUGH; |
| case AtomicExpr::AO__c11_atomic_fetch_sub: |
| case AtomicExpr::AO__opencl_atomic_fetch_sub: |
| case AtomicExpr::AO__atomic_fetch_sub: |
| LibCallName = "__atomic_fetch_sub"; |
| AddDirectArgument(*this, Args, UseOptimizedLibcall, Val1.getPointer(), |
| LoweredMemTy, E->getExprLoc(), sizeChars); |
| break; |
| // T __atomic_xor_fetch_N(T *mem, T val, int order) |
| // T __atomic_fetch_xor_N(T *mem, T val, int order) |
| case AtomicExpr::AO__atomic_xor_fetch: |
| PostOp = llvm::Instruction::Xor; |
| LLVM_FALLTHROUGH; |
| case AtomicExpr::AO__c11_atomic_fetch_xor: |
| case AtomicExpr::AO__opencl_atomic_fetch_xor: |
| case AtomicExpr::AO__atomic_fetch_xor: |
| LibCallName = "__atomic_fetch_xor"; |
| AddDirectArgument(*this, Args, UseOptimizedLibcall, Val1.getPointer(), |
| MemTy, E->getExprLoc(), sizeChars); |
| break; |
| case AtomicExpr::AO__atomic_min_fetch: |
| PostOpMinMax = true; |
| LLVM_FALLTHROUGH; |
| case AtomicExpr::AO__c11_atomic_fetch_min: |
| case AtomicExpr::AO__atomic_fetch_min: |
| case AtomicExpr::AO__opencl_atomic_fetch_min: |
| LibCallName = E->getValueType()->isSignedIntegerType() |
| ? "__atomic_fetch_min" |
| : "__atomic_fetch_umin"; |
| AddDirectArgument(*this, Args, UseOptimizedLibcall, Val1.getPointer(), |
| LoweredMemTy, E->getExprLoc(), sizeChars); |
| break; |
| case AtomicExpr::AO__atomic_max_fetch: |
| PostOpMinMax = true; |
| LLVM_FALLTHROUGH; |
| case AtomicExpr::AO__c11_atomic_fetch_max: |
| case AtomicExpr::AO__atomic_fetch_max: |
| case AtomicExpr::AO__opencl_atomic_fetch_max: |
| LibCallName = E->getValueType()->isSignedIntegerType() |
| ? "__atomic_fetch_max" |
| : "__atomic_fetch_umax"; |
| AddDirectArgument(*this, Args, UseOptimizedLibcall, Val1.getPointer(), |
| LoweredMemTy, E->getExprLoc(), sizeChars); |
| break; |
| // T __atomic_nand_fetch_N(T *mem, T val, int order) |
| // T __atomic_fetch_nand_N(T *mem, T val, int order) |
| case AtomicExpr::AO__atomic_nand_fetch: |
| PostOp = llvm::Instruction::And; // the NOT is special cased below |
| LLVM_FALLTHROUGH; |
| case AtomicExpr::AO__atomic_fetch_nand: |
| LibCallName = "__atomic_fetch_nand"; |
| AddDirectArgument(*this, Args, UseOptimizedLibcall, Val1.getPointer(), |
| MemTy, E->getExprLoc(), sizeChars); |
| break; |
| } |
| |
| if (E->isOpenCL()) { |
| LibCallName = std::string("__opencl") + |
| StringRef(LibCallName).drop_front(1).str(); |
| |
| } |
| // Optimized functions have the size in their name. |
| if (UseOptimizedLibcall) |
| LibCallName += "_" + llvm::utostr(Size); |
| // By default, assume we return a value of the atomic type. |
| if (!HaveRetTy) { |
| if (UseOptimizedLibcall) { |
| // Value is returned directly. |
| // The function returns an appropriately sized integer type. |
| RetTy = getContext().getIntTypeForBitwidth( |
| getContext().toBits(sizeChars), /*Signed=*/false); |
| } else { |
| // Value is returned through parameter before the order. |
| RetTy = getContext().VoidTy; |
| Args.add(RValue::get(EmitCastToVoidPtr(Dest.getPointer())), |
| getContext().VoidPtrTy); |
| } |
| } |
| // order is always the last parameter |
| Args.add(RValue::get(Order), |
| getContext().IntTy); |
| if (E->isOpenCL()) |
| Args.add(RValue::get(Scope), getContext().IntTy); |
| |
| // PostOp is only needed for the atomic_*_fetch operations, and |
| // thus is only needed for and implemented in the |
| // UseOptimizedLibcall codepath. |
| assert(UseOptimizedLibcall || (!PostOp && !PostOpMinMax)); |
| |
| RValue Res = emitAtomicLibcall(*this, LibCallName, RetTy, Args); |
| // The value is returned directly from the libcall. |
| if (E->isCmpXChg()) |
| return Res; |
| |
| // The value is returned directly for optimized libcalls but the expr |
| // provided an out-param. |
| if (UseOptimizedLibcall && Res.getScalarVal()) { |
| llvm::Value *ResVal = Res.getScalarVal(); |
| if (PostOpMinMax) { |
| llvm::Value *LoadVal1 = Args[1].getRValue(*this).getScalarVal(); |
| ResVal = EmitPostAtomicMinMax(Builder, E->getOp(), |
| E->getValueType()->isSignedIntegerType(), |
| ResVal, LoadVal1); |
| } else if (PostOp) { |
| llvm::Value *LoadVal1 = Args[1].getRValue(*this).getScalarVal(); |
| ResVal = Builder.CreateBinOp(PostOp, ResVal, LoadVal1); |
| } |
| if (E->getOp() == AtomicExpr::AO__atomic_nand_fetch) |
| ResVal = Builder.CreateNot(ResVal); |
| |
| Builder.CreateStore( |
| ResVal, |
| Builder.CreateBitCast(Dest, ResVal->getType()->getPointerTo())); |
| } |
| |
| if (RValTy->isVoidType()) |
| return RValue::get(nullptr); |
| |
| return convertTempToRValue( |
| Builder.CreateBitCast(Dest, ConvertTypeForMem(RValTy)->getPointerTo()), |
| RValTy, E->getExprLoc()); |
| } |
| |
| bool IsStore = E->getOp() == AtomicExpr::AO__c11_atomic_store || |
| E->getOp() == AtomicExpr::AO__opencl_atomic_store || |
| E->getOp() == AtomicExpr::AO__atomic_store || |
| E->getOp() == AtomicExpr::AO__atomic_store_n; |
| bool IsLoad = E->getOp() == AtomicExpr::AO__c11_atomic_load || |
| E->getOp() == AtomicExpr::AO__opencl_atomic_load || |
| E->getOp() == AtomicExpr::AO__atomic_load || |
| E->getOp() == AtomicExpr::AO__atomic_load_n; |
| |
| if (isa<llvm::ConstantInt>(Order)) { |
| auto ord = cast<llvm::ConstantInt>(Order)->getZExtValue(); |
| // We should not ever get to a case where the ordering isn't a valid C ABI |
| // value, but it's hard to enforce that in general. |
| if (llvm::isValidAtomicOrderingCABI(ord)) |
| switch ((llvm::AtomicOrderingCABI)ord) { |
| case llvm::AtomicOrderingCABI::relaxed: |
| EmitAtomicOp(*this, E, Dest, Ptr, Val1, Val2, IsWeak, OrderFail, Size, |
| llvm::AtomicOrdering::Monotonic, Scope); |
| break; |
| case llvm::AtomicOrderingCABI::consume: |
| case llvm::AtomicOrderingCABI::acquire: |
| if (IsStore) |
| break; // Avoid crashing on code with undefined behavior |
| EmitAtomicOp(*this, E, Dest, Ptr, Val1, Val2, IsWeak, OrderFail, Size, |
| llvm::AtomicOrdering::Acquire, Scope); |
| break; |
| case llvm::AtomicOrderingCABI::release: |
| if (IsLoad) |
| break; // Avoid crashing on code with undefined behavior |
| EmitAtomicOp(*this, E, Dest, Ptr, Val1, Val2, IsWeak, OrderFail, Size, |
| llvm::AtomicOrdering::Release, Scope); |
| break; |
| case llvm::AtomicOrderingCABI::acq_rel: |
| if (IsLoad || IsStore) |
| break; // Avoid crashing on code with undefined behavior |
| EmitAtomicOp(*this, E, Dest, Ptr, Val1, Val2, IsWeak, OrderFail, Size, |
| llvm::AtomicOrdering::AcquireRelease, Scope); |
| break; |
| case llvm::AtomicOrderingCABI::seq_cst: |
| EmitAtomicOp(*this, E, Dest, Ptr, Val1, Val2, IsWeak, OrderFail, Size, |
| llvm::AtomicOrdering::SequentiallyConsistent, Scope); |
| break; |
| } |
| if (RValTy->isVoidType()) |
| return RValue::get(nullptr); |
| |
| return convertTempToRValue( |
| Builder.CreateBitCast(Dest, ConvertTypeForMem(RValTy)->getPointerTo( |
| Dest.getAddressSpace())), |
| RValTy, E->getExprLoc()); |
| } |
| |
| // Long case, when Order isn't obviously constant. |
| |
| // Create all the relevant BB's |
| llvm::BasicBlock *MonotonicBB = nullptr, *AcquireBB = nullptr, |
| *ReleaseBB = nullptr, *AcqRelBB = nullptr, |
| *SeqCstBB = nullptr; |
| MonotonicBB = createBasicBlock("monotonic", CurFn); |
| if (!IsStore) |
| AcquireBB = createBasicBlock("acquire", CurFn); |
| if (!IsLoad) |
| ReleaseBB = createBasicBlock("release", CurFn); |
| if (!IsLoad && !IsStore) |
| AcqRelBB = createBasicBlock("acqrel", CurFn); |
| SeqCstBB = createBasicBlock("seqcst", CurFn); |
| llvm::BasicBlock *ContBB = createBasicBlock("atomic.continue", CurFn); |
| |
| // Create the switch for the split |
| // MonotonicBB is arbitrarily chosen as the default case; in practice, this |
| // doesn't matter unless someone is crazy enough to use something that |
| // doesn't fold to a constant for the ordering. |
| Order = Builder.CreateIntCast(Order, Builder.getInt32Ty(), false); |
| llvm::SwitchInst *SI = Builder.CreateSwitch(Order, MonotonicBB); |
| |
| // Emit all the different atomics |
| Builder.SetInsertPoint(MonotonicBB); |
| EmitAtomicOp(*this, E, Dest, Ptr, Val1, Val2, IsWeak, OrderFail, Size, |
| llvm::AtomicOrdering::Monotonic, Scope); |
| Builder.CreateBr(ContBB); |
| if (!IsStore) { |
| Builder.SetInsertPoint(AcquireBB); |
| EmitAtomicOp(*this, E, Dest, Ptr, Val1, Val2, IsWeak, OrderFail, Size, |
| llvm::AtomicOrdering::Acquire, Scope); |
| Builder.CreateBr(ContBB); |
| SI->addCase(Builder.getInt32((int)llvm::AtomicOrderingCABI::consume), |
| AcquireBB); |
| SI->addCase(Builder.getInt32((int)llvm::AtomicOrderingCABI::acquire), |
| AcquireBB); |
| } |
| if (!IsLoad) { |
| Builder.SetInsertPoint(ReleaseBB); |
| EmitAtomicOp(*this, E, Dest, Ptr, Val1, Val2, IsWeak, OrderFail, Size, |
| llvm::AtomicOrdering::Release, Scope); |
| Builder.CreateBr(ContBB); |
| SI->addCase(Builder.getInt32((int)llvm::AtomicOrderingCABI::release), |
| ReleaseBB); |
| } |
| if (!IsLoad && !IsStore) { |
| Builder.SetInsertPoint(AcqRelBB); |
| EmitAtomicOp(*this, E, Dest, Ptr, Val1, Val2, IsWeak, OrderFail, Size, |
| llvm::AtomicOrdering::AcquireRelease, Scope); |
| Builder.CreateBr(ContBB); |
| SI->addCase(Builder.getInt32((int)llvm::AtomicOrderingCABI::acq_rel), |
| AcqRelBB); |
| } |
| Builder.SetInsertPoint(SeqCstBB); |
| EmitAtomicOp(*this, E, Dest, Ptr, Val1, Val2, IsWeak, OrderFail, Size, |
| llvm::AtomicOrdering::SequentiallyConsistent, Scope); |
| Builder.CreateBr(ContBB); |
| SI->addCase(Builder.getInt32((int)llvm::AtomicOrderingCABI::seq_cst), |
| SeqCstBB); |
| |
| // Cleanup and return |
| Builder.SetInsertPoint(ContBB); |
| if (RValTy->isVoidType()) |
| return RValue::get(nullptr); |
| |
| assert(Atomics.getValueSizeInBits() <= Atomics.getAtomicSizeInBits()); |
| return convertTempToRValue( |
| Builder.CreateBitCast(Dest, ConvertTypeForMem(RValTy)->getPointerTo( |
| Dest.getAddressSpace())), |
| RValTy, E->getExprLoc()); |
| } |
| |
| Address AtomicInfo::emitCastToAtomicIntPointer(Address addr) const { |
| unsigned addrspace = |
| cast<llvm::PointerType>(addr.getPointer()->getType())->getAddressSpace(); |
| llvm::IntegerType *ty = |
| llvm::IntegerType::get(CGF.getLLVMContext(), AtomicSizeInBits); |
| return CGF.Builder.CreateBitCast(addr, ty->getPointerTo(addrspace)); |
| } |
| |
| Address AtomicInfo::convertToAtomicIntPointer(Address Addr) const { |
| llvm::Type *Ty = Addr.getElementType(); |
| uint64_t SourceSizeInBits = CGF.CGM.getDataLayout().getTypeSizeInBits(Ty); |
| if (SourceSizeInBits != AtomicSizeInBits) { |
| Address Tmp = CreateTempAlloca(); |
| CGF.Builder.CreateMemCpy(Tmp, Addr, |
| std::min(AtomicSizeInBits, SourceSizeInBits) / 8); |
| Addr = Tmp; |
| } |
| |
| return emitCastToAtomicIntPointer(Addr); |
| } |
| |
| RValue AtomicInfo::convertAtomicTempToRValue(Address addr, |
| AggValueSlot resultSlot, |
| SourceLocation loc, |
| bool asValue) const { |
| if (LVal.isSimple()) { |
| if (EvaluationKind == TEK_Aggregate) |
| return resultSlot.asRValue(); |
| |
| // Drill into the padding structure if we have one. |
| if (hasPadding()) |
| addr = CGF.Builder.CreateStructGEP(addr, 0); |
| |
| // Otherwise, just convert the temporary to an r-value using the |
| // normal conversion routine. |
| return CGF.convertTempToRValue(addr, getValueType(), loc); |
| } |
| if (!asValue) |
| // Get RValue from temp memory as atomic for non-simple lvalues |
| return RValue::get(CGF.Builder.CreateLoad(addr)); |
| if (LVal.isBitField()) |
| return CGF.EmitLoadOfBitfieldLValue( |
| LValue::MakeBitfield(addr, LVal.getBitFieldInfo(), LVal.getType(), |
| LVal.getBaseInfo(), TBAAAccessInfo()), loc); |
| if (LVal.isVectorElt()) |
| return CGF.EmitLoadOfLValue( |
| LValue::MakeVectorElt(addr, LVal.getVectorIdx(), LVal.getType(), |
| LVal.getBaseInfo(), TBAAAccessInfo()), loc); |
| assert(LVal.isExtVectorElt()); |
| return CGF.EmitLoadOfExtVectorElementLValue(LValue::MakeExtVectorElt( |
| addr, LVal.getExtVectorElts(), LVal.getType(), |
| LVal.getBaseInfo(), TBAAAccessInfo())); |
| } |
| |
| RValue AtomicInfo::ConvertIntToValueOrAtomic(llvm::Value *IntVal, |
| AggValueSlot ResultSlot, |
| SourceLocation Loc, |
| bool AsValue) const { |
| // Try not to in some easy cases. |
| assert(IntVal->getType()->isIntegerTy() && "Expected integer value"); |
| if (getEvaluationKind() == TEK_Scalar && |
| (((!LVal.isBitField() || |
| LVal.getBitFieldInfo().Size == ValueSizeInBits) && |
| !hasPadding()) || |
| !AsValue)) { |
| auto *ValTy = AsValue |
| ? CGF.ConvertTypeForMem(ValueTy) |
| : getAtomicAddress().getType()->getPointerElementType(); |
| if (ValTy->isIntegerTy()) { |
| assert(IntVal->getType() == ValTy && "Different integer types."); |
| return RValue::get(CGF.EmitFromMemory(IntVal, ValueTy)); |
| } else if (ValTy->isPointerTy()) |
| return RValue::get(CGF.Builder.CreateIntToPtr(IntVal, ValTy)); |
| else if (llvm::CastInst::isBitCastable(IntVal->getType(), ValTy)) |
| return RValue::get(CGF.Builder.CreateBitCast(IntVal, ValTy)); |
| } |
| |
| // Create a temporary. This needs to be big enough to hold the |
| // atomic integer. |
| Address Temp = Address::invalid(); |
| bool TempIsVolatile = false; |
| if (AsValue && getEvaluationKind() == TEK_Aggregate) { |
| assert(!ResultSlot.isIgnored()); |
| Temp = ResultSlot.getAddress(); |
| TempIsVolatile = ResultSlot.isVolatile(); |
| } else { |
| Temp = CreateTempAlloca(); |
| } |
| |
| // Slam the integer into the temporary. |
| Address CastTemp = emitCastToAtomicIntPointer(Temp); |
| CGF.Builder.CreateStore(IntVal, CastTemp) |
| ->setVolatile(TempIsVolatile); |
| |
| return convertAtomicTempToRValue(Temp, ResultSlot, Loc, AsValue); |
| } |
| |
| void AtomicInfo::EmitAtomicLoadLibcall(llvm::Value *AddForLoaded, |
| llvm::AtomicOrdering AO, bool) { |
| // void __atomic_load(size_t size, void *mem, void *return, int order); |
| CallArgList Args; |
| Args.add(RValue::get(getAtomicSizeValue()), CGF.getContext().getSizeType()); |
| Args.add(RValue::get(CGF.EmitCastToVoidPtr(getAtomicPointer())), |
| CGF.getContext().VoidPtrTy); |
| Args.add(RValue::get(CGF.EmitCastToVoidPtr(AddForLoaded)), |
| CGF.getContext().VoidPtrTy); |
| Args.add( |
| RValue::get(llvm::ConstantInt::get(CGF.IntTy, (int)llvm::toCABI(AO))), |
| CGF.getContext().IntTy); |
| emitAtomicLibcall(CGF, "__atomic_load", CGF.getContext().VoidTy, Args); |
| } |
| |
| llvm::Value *AtomicInfo::EmitAtomicLoadOp(llvm::AtomicOrdering AO, |
| bool IsVolatile) { |
| // Okay, we're doing this natively. |
| Address Addr = getAtomicAddressAsAtomicIntPointer(); |
| llvm::LoadInst *Load = CGF.Builder.CreateLoad(Addr, "atomic-load"); |
| Load->setAtomic(AO); |
| |
| // Other decoration. |
| if (IsVolatile) |
| Load->setVolatile(true); |
| CGF.CGM.DecorateInstructionWithTBAA(Load, LVal.getTBAAInfo()); |
| return Load; |
| } |
| |
| /// An LValue is a candidate for having its loads and stores be made atomic if |
| /// we are operating under /volatile:ms *and* the LValue itself is volatile and |
| /// performing such an operation can be performed without a libcall. |
| bool CodeGenFunction::LValueIsSuitableForInlineAtomic(LValue LV) { |
| if (!CGM.getCodeGenOpts().MSVolatile) return false; |
| AtomicInfo AI(*this, LV); |
| bool IsVolatile = LV.isVolatile() || hasVolatileMember(LV.getType()); |
| // An atomic is inline if we don't need to use a libcall. |
| bool AtomicIsInline = !AI.shouldUseLibcall(); |
| // MSVC doesn't seem to do this for types wider than a pointer. |
| if (getContext().getTypeSize(LV.getType()) > |
| getContext().getTypeSize(getContext().getIntPtrType())) |
| return false; |
| return IsVolatile && AtomicIsInline; |
| } |
| |
| RValue CodeGenFunction::EmitAtomicLoad(LValue LV, SourceLocation SL, |
| AggValueSlot Slot) { |
| llvm::AtomicOrdering AO; |
| bool IsVolatile = LV.isVolatileQualified(); |
| if (LV.getType()->isAtomicType()) { |
| AO = llvm::AtomicOrdering::SequentiallyConsistent; |
| } else { |
| AO = llvm::AtomicOrdering::Acquire; |
| IsVolatile = true; |
| } |
| return EmitAtomicLoad(LV, SL, AO, IsVolatile, Slot); |
| } |
| |
| RValue AtomicInfo::EmitAtomicLoad(AggValueSlot ResultSlot, SourceLocation Loc, |
| bool AsValue, llvm::AtomicOrdering AO, |
| bool IsVolatile) { |
| // Check whether we should use a library call. |
| if (shouldUseLibcall()) { |
| Address TempAddr = Address::invalid(); |
| if (LVal.isSimple() && !ResultSlot.isIgnored()) { |
| assert(getEvaluationKind() == TEK_Aggregate); |
| TempAddr = ResultSlot.getAddress(); |
| } else |
| TempAddr = CreateTempAlloca(); |
| |
| EmitAtomicLoadLibcall(TempAddr.getPointer(), AO, IsVolatile); |
| |
| // Okay, turn that back into the original value or whole atomic (for |
| // non-simple lvalues) type. |
| return convertAtomicTempToRValue(TempAddr, ResultSlot, Loc, AsValue); |
| } |
| |
| // Okay, we're doing this natively. |
| auto *Load = EmitAtomicLoadOp(AO, IsVolatile); |
| |
| // If we're ignoring an aggregate return, don't do anything. |
| if (getEvaluationKind() == TEK_Aggregate && ResultSlot.isIgnored()) |
| return RValue::getAggregate(Address::invalid(), false); |
| |
| // Okay, turn that back into the original value or atomic (for non-simple |
| // lvalues) type. |
| return ConvertIntToValueOrAtomic(Load, ResultSlot, Loc, AsValue); |
| } |
| |
| /// Emit a load from an l-value of atomic type. Note that the r-value |
| /// we produce is an r-value of the atomic *value* type. |
| RValue CodeGenFunction::EmitAtomicLoad(LValue src, SourceLocation loc, |
| llvm::AtomicOrdering AO, bool IsVolatile, |
| AggValueSlot resultSlot) { |
| AtomicInfo Atomics(*this, src); |
| return Atomics.EmitAtomicLoad(resultSlot, loc, /*AsValue=*/true, AO, |
| IsVolatile); |
| } |
| |
| /// Copy an r-value into memory as part of storing to an atomic type. |
| /// This needs to create a bit-pattern suitable for atomic operations. |
| void AtomicInfo::emitCopyIntoMemory(RValue rvalue) const { |
| assert(LVal.isSimple()); |
| // If we have an r-value, the rvalue should be of the atomic type, |
| // which means that the caller is responsible for having zeroed |
| // any padding. Just do an aggregate copy of that type. |
| if (rvalue.isAggregate()) { |
| LValue Dest = CGF.MakeAddrLValue(getAtomicAddress(), getAtomicType()); |
| LValue Src = CGF.MakeAddrLValue(rvalue.getAggregateAddress(), |
| getAtomicType()); |
| bool IsVolatile = rvalue.isVolatileQualified() || |
| LVal.isVolatileQualified(); |
| CGF.EmitAggregateCopy(Dest, Src, getAtomicType(), |
| AggValueSlot::DoesNotOverlap, IsVolatile); |
| return; |
| } |
| |
| // Okay, otherwise we're copying stuff. |
| |
| // Zero out the buffer if necessary. |
| emitMemSetZeroIfNecessary(); |
| |
| // Drill past the padding if present. |
| LValue TempLVal = projectValue(); |
| |
| // Okay, store the rvalue in. |
| if (rvalue.isScalar()) { |
| CGF.EmitStoreOfScalar(rvalue.getScalarVal(), TempLVal, /*init*/ true); |
| } else { |
| CGF.EmitStoreOfComplex(rvalue.getComplexVal(), TempLVal, /*init*/ true); |
| } |
| } |
| |
| |
| /// Materialize an r-value into memory for the purposes of storing it |
| /// to an atomic type. |
| Address AtomicInfo::materializeRValue(RValue rvalue) const { |
| // Aggregate r-values are already in memory, and EmitAtomicStore |
| // requires them to be values of the atomic type. |
| if (rvalue.isAggregate()) |
| return rvalue.getAggregateAddress(); |
| |
| // Otherwise, make a temporary and materialize into it. |
| LValue TempLV = CGF.MakeAddrLValue(CreateTempAlloca(), getAtomicType()); |
| AtomicInfo Atomics(CGF, TempLV); |
| Atomics.emitCopyIntoMemory(rvalue); |
| return TempLV.getAddress(CGF); |
| } |
| |
| llvm::Value *AtomicInfo::convertRValueToInt(RValue RVal) const { |
| // If we've got a scalar value of the right size, try to avoid going |
| // through memory. |
| if (RVal.isScalar() && (!hasPadding() || !LVal.isSimple())) { |
| llvm::Value *Value = RVal.getScalarVal(); |
| if (isa<llvm::IntegerType>(Value->getType())) |
| return CGF.EmitToMemory(Value, ValueTy); |
| else { |
| llvm::IntegerType *InputIntTy = llvm::IntegerType::get( |
| CGF.getLLVMContext(), |
| LVal.isSimple() ? getValueSizeInBits() : getAtomicSizeInBits()); |
| if (isa<llvm::PointerType>(Value->getType())) |
| return CGF.Builder.CreatePtrToInt(Value, InputIntTy); |
| else if (llvm::BitCastInst::isBitCastable(Value->getType(), InputIntTy)) |
| return CGF.Builder.CreateBitCast(Value, InputIntTy); |
| } |
| } |
| // Otherwise, we need to go through memory. |
| // Put the r-value in memory. |
| Address Addr = materializeRValue(RVal); |
| |
| // Cast the temporary to the atomic int type and pull a value out. |
| Addr = emitCastToAtomicIntPointer(Addr); |
| return CGF.Builder.CreateLoad(Addr); |
| } |
| |
| std::pair<llvm::Value *, llvm::Value *> AtomicInfo::EmitAtomicCompareExchangeOp( |
| llvm::Value *ExpectedVal, llvm::Value *DesiredVal, |
| llvm::AtomicOrdering Success, llvm::AtomicOrdering Failure, bool IsWeak) { |
| // Do the atomic store. |
| Address Addr = getAtomicAddressAsAtomicIntPointer(); |
| auto *Inst = CGF.Builder.CreateAtomicCmpXchg(Addr.getPointer(), |
| ExpectedVal, DesiredVal, |
| Success, Failure); |
| // Other decoration. |
| Inst->setVolatile(LVal.isVolatileQualified()); |
| Inst->setWeak(IsWeak); |
| |
| // Okay, turn that back into the original value type. |
| auto *PreviousVal = CGF.Builder.CreateExtractValue(Inst, /*Idxs=*/0); |
| auto *SuccessFailureVal = CGF.Builder.CreateExtractValue(Inst, /*Idxs=*/1); |
| return std::make_pair(PreviousVal, SuccessFailureVal); |
| } |
| |
| llvm::Value * |
| AtomicInfo::EmitAtomicCompareExchangeLibcall(llvm::Value *ExpectedAddr, |
| llvm::Value *DesiredAddr, |
| llvm::AtomicOrdering Success, |
| llvm::AtomicOrdering Failure) { |
| // bool __atomic_compare_exchange(size_t size, void *obj, void *expected, |
| // void *desired, int success, int failure); |
| CallArgList Args; |
| Args.add(RValue::get(getAtomicSizeValue()), CGF.getContext().getSizeType()); |
| Args.add(RValue::get(CGF.EmitCastToVoidPtr(getAtomicPointer())), |
| CGF.getContext().VoidPtrTy); |
| Args.add(RValue::get(CGF.EmitCastToVoidPtr(ExpectedAddr)), |
| CGF.getContext().VoidPtrTy); |
| Args.add(RValue::get(CGF.EmitCastToVoidPtr(DesiredAddr)), |
| CGF.getContext().VoidPtrTy); |
| Args.add(RValue::get( |
| llvm::ConstantInt::get(CGF.IntTy, (int)llvm::toCABI(Success))), |
| CGF.getContext().IntTy); |
| Args.add(RValue::get( |
| llvm::ConstantInt::get(CGF.IntTy, (int)llvm::toCABI(Failure))), |
| CGF.getContext().IntTy); |
| auto SuccessFailureRVal = emitAtomicLibcall(CGF, "__atomic_compare_exchange", |
| CGF.getContext().BoolTy, Args); |
| |
| return SuccessFailureRVal.getScalarVal(); |
| } |
| |
| std::pair<RValue, llvm::Value *> AtomicInfo::EmitAtomicCompareExchange( |
| RValue Expected, RValue Desired, llvm::AtomicOrdering Success, |
| llvm::AtomicOrdering Failure, bool IsWeak) { |
| if (isStrongerThan(Failure, Success)) |
| // Don't assert on undefined behavior "failure argument shall be no stronger |
| // than the success argument". |
| Failure = llvm::AtomicCmpXchgInst::getStrongestFailureOrdering(Success); |
| |
| // Check whether we should use a library call. |
| if (shouldUseLibcall()) { |
| // Produce a source address. |
| Address ExpectedAddr = materializeRValue(Expected); |
| Address DesiredAddr = materializeRValue(Desired); |
| auto *Res = EmitAtomicCompareExchangeLibcall(ExpectedAddr.getPointer(), |
| DesiredAddr.getPointer(), |
| Success, Failure); |
| return std::make_pair( |
| convertAtomicTempToRValue(ExpectedAddr, AggValueSlot::ignored(), |
| SourceLocation(), /*AsValue=*/false), |
| Res); |
| } |
| |
| // If we've got a scalar value of the right size, try to avoid going |
| // through memory. |
| auto *ExpectedVal = convertRValueToInt(Expected); |
| auto *DesiredVal = convertRValueToInt(Desired); |
| auto Res = EmitAtomicCompareExchangeOp(ExpectedVal, DesiredVal, Success, |
| Failure, IsWeak); |
| return std::make_pair( |
| ConvertIntToValueOrAtomic(Res.first, AggValueSlot::ignored(), |
| SourceLocation(), /*AsValue=*/false), |
| Res.second); |
| } |
| |
| static void |
| EmitAtomicUpdateValue(CodeGenFunction &CGF, AtomicInfo &Atomics, RValue OldRVal, |
| const llvm::function_ref<RValue(RValue)> &UpdateOp, |
| Address DesiredAddr) { |
| RValue UpRVal; |
| LValue AtomicLVal = Atomics.getAtomicLValue(); |
| LValue DesiredLVal; |
| if (AtomicLVal.isSimple()) { |
| UpRVal = OldRVal; |
| DesiredLVal = CGF.MakeAddrLValue(DesiredAddr, AtomicLVal.getType()); |
| } else { |
| // Build new lvalue for temp address. |
| Address Ptr = Atomics.materializeRValue(OldRVal); |
| LValue UpdateLVal; |
| if (AtomicLVal.isBitField()) { |
| UpdateLVal = |
| LValue::MakeBitfield(Ptr, AtomicLVal.getBitFieldInfo(), |
| AtomicLVal.getType(), |
| AtomicLVal.getBaseInfo(), |
| AtomicLVal.getTBAAInfo()); |
| DesiredLVal = |
| LValue::MakeBitfield(DesiredAddr, AtomicLVal.getBitFieldInfo(), |
| AtomicLVal.getType(), AtomicLVal.getBaseInfo(), |
| AtomicLVal.getTBAAInfo()); |
| } else if (AtomicLVal.isVectorElt()) { |
| UpdateLVal = LValue::MakeVectorElt(Ptr, AtomicLVal.getVectorIdx(), |
| AtomicLVal.getType(), |
| AtomicLVal.getBaseInfo(), |
| AtomicLVal.getTBAAInfo()); |
| DesiredLVal = LValue::MakeVectorElt( |
| DesiredAddr, AtomicLVal.getVectorIdx(), AtomicLVal.getType(), |
| AtomicLVal.getBaseInfo(), AtomicLVal.getTBAAInfo()); |
| } else { |
| assert(AtomicLVal.isExtVectorElt()); |
| UpdateLVal = LValue::MakeExtVectorElt(Ptr, AtomicLVal.getExtVectorElts(), |
| AtomicLVal.getType(), |
| AtomicLVal.getBaseInfo(), |
| AtomicLVal.getTBAAInfo()); |
| DesiredLVal = LValue::MakeExtVectorElt( |
| DesiredAddr, AtomicLVal.getExtVectorElts(), AtomicLVal.getType(), |
| AtomicLVal.getBaseInfo(), AtomicLVal.getTBAAInfo()); |
| } |
| UpRVal = CGF.EmitLoadOfLValue(UpdateLVal, SourceLocation()); |
| } |
| // Store new value in the corresponding memory area. |
| RValue NewRVal = UpdateOp(UpRVal); |
| if (NewRVal.isScalar()) { |
| CGF.EmitStoreThroughLValue(NewRVal, DesiredLVal); |
| } else { |
| assert(NewRVal.isComplex()); |
| CGF.EmitStoreOfComplex(NewRVal.getComplexVal(), DesiredLVal, |
| /*isInit=*/false); |
| } |
| } |
| |
| void AtomicInfo::EmitAtomicUpdateLibcall( |
| llvm::AtomicOrdering AO, const llvm::function_ref<RValue(RValue)> &UpdateOp, |
| bool IsVolatile) { |
| auto Failure = llvm::AtomicCmpXchgInst::getStrongestFailureOrdering(AO); |
| |
| Address ExpectedAddr = CreateTempAlloca(); |
| |
| EmitAtomicLoadLibcall(ExpectedAddr.getPointer(), AO, IsVolatile); |
| auto *ContBB = CGF.createBasicBlock("atomic_cont"); |
| auto *ExitBB = CGF.createBasicBlock("atomic_exit"); |
| CGF.EmitBlock(ContBB); |
| Address DesiredAddr = CreateTempAlloca(); |
| if ((LVal.isBitField() && BFI.Size != ValueSizeInBits) || |
| requiresMemSetZero(getAtomicAddress().getElementType())) { |
| auto *OldVal = CGF.Builder.CreateLoad(ExpectedAddr); |
| CGF.Builder.CreateStore(OldVal, DesiredAddr); |
| } |
| auto OldRVal = convertAtomicTempToRValue(ExpectedAddr, |
| AggValueSlot::ignored(), |
| SourceLocation(), /*AsValue=*/false); |
| EmitAtomicUpdateValue(CGF, *this, OldRVal, UpdateOp, DesiredAddr); |
| auto *Res = |
| EmitAtomicCompareExchangeLibcall(ExpectedAddr.getPointer(), |
| DesiredAddr.getPointer(), |
| AO, Failure); |
| CGF.Builder.CreateCondBr(Res, ExitBB, ContBB); |
| CGF.EmitBlock(ExitBB, /*IsFinished=*/true); |
| } |
| |
| void AtomicInfo::EmitAtomicUpdateOp( |
| llvm::AtomicOrdering AO, const llvm::function_ref<RValue(RValue)> &UpdateOp, |
| bool IsVolatile) { |
| auto Failure = llvm::AtomicCmpXchgInst::getStrongestFailureOrdering(AO); |
| |
| // Do the atomic load. |
| auto *OldVal = EmitAtomicLoadOp(Failure, IsVolatile); |
| // For non-simple lvalues perform compare-and-swap procedure. |
| auto *ContBB = CGF.createBasicBlock("atomic_cont"); |
| auto *ExitBB = CGF.createBasicBlock("atomic_exit"); |
| auto *CurBB = CGF.Builder.GetInsertBlock(); |
| CGF.EmitBlock(ContBB); |
| llvm::PHINode *PHI = CGF.Builder.CreatePHI(OldVal->getType(), |
| /*NumReservedValues=*/2); |
| PHI->addIncoming(OldVal, CurBB); |
| Address NewAtomicAddr = CreateTempAlloca(); |
| Address NewAtomicIntAddr = emitCastToAtomicIntPointer(NewAtomicAddr); |
| if ((LVal.isBitField() && BFI.Size != ValueSizeInBits) || |
| requiresMemSetZero(getAtomicAddress().getElementType())) { |
| CGF.Builder.CreateStore(PHI, NewAtomicIntAddr); |
| } |
| auto OldRVal = ConvertIntToValueOrAtomic(PHI, AggValueSlot::ignored(), |
| SourceLocation(), /*AsValue=*/false); |
| EmitAtomicUpdateValue(CGF, *this, OldRVal, UpdateOp, NewAtomicAddr); |
| auto *DesiredVal = CGF.Builder.CreateLoad(NewAtomicIntAddr); |
| // Try to write new value using cmpxchg operation. |
| auto Res = EmitAtomicCompareExchangeOp(PHI, DesiredVal, AO, Failure); |
| PHI->addIncoming(Res.first, CGF.Builder.GetInsertBlock()); |
| CGF.Builder.CreateCondBr(Res.second, ExitBB, ContBB); |
| CGF.EmitBlock(ExitBB, /*IsFinished=*/true); |
| } |
| |
| static void EmitAtomicUpdateValue(CodeGenFunction &CGF, AtomicInfo &Atomics, |
| RValue UpdateRVal, Address DesiredAddr) { |
| LValue AtomicLVal = Atomics.getAtomicLValue(); |
| LValue DesiredLVal; |
| // Build new lvalue for temp address. |
| if (AtomicLVal.isBitField()) { |
| DesiredLVal = |
| LValue::MakeBitfield(DesiredAddr, AtomicLVal.getBitFieldInfo(), |
| AtomicLVal.getType(), AtomicLVal.getBaseInfo(), |
| AtomicLVal.getTBAAInfo()); |
| } else if (AtomicLVal.isVectorElt()) { |
| DesiredLVal = |
| LValue::MakeVectorElt(DesiredAddr, AtomicLVal.getVectorIdx(), |
| AtomicLVal.getType(), AtomicLVal.getBaseInfo(), |
| AtomicLVal.getTBAAInfo()); |
| } else { |
| assert(AtomicLVal.isExtVectorElt()); |
| DesiredLVal = LValue::MakeExtVectorElt( |
| DesiredAddr, AtomicLVal.getExtVectorElts(), AtomicLVal.getType(), |
| AtomicLVal.getBaseInfo(), AtomicLVal.getTBAAInfo()); |
| } |
| // Store new value in the corresponding memory area. |
| assert(UpdateRVal.isScalar()); |
| CGF.EmitStoreThroughLValue(UpdateRVal, DesiredLVal); |
| } |
| |
| void AtomicInfo::EmitAtomicUpdateLibcall(llvm::AtomicOrdering AO, |
| RValue UpdateRVal, bool IsVolatile) { |
| auto Failure = llvm::AtomicCmpXchgInst::getStrongestFailureOrdering(AO); |
| |
| Address ExpectedAddr = CreateTempAlloca(); |
| |
| EmitAtomicLoadLibcall(ExpectedAddr.getPointer(), AO, IsVolatile); |
| auto *ContBB = CGF.createBasicBlock("atomic_cont"); |
| auto *ExitBB = CGF.createBasicBlock("atomic_exit"); |
| CGF.EmitBlock(ContBB); |
| Address DesiredAddr = CreateTempAlloca(); |
| if ((LVal.isBitField() && BFI.Size != ValueSizeInBits) || |
| requiresMemSetZero(getAtomicAddress().getElementType())) { |
| auto *OldVal = CGF.Builder.CreateLoad(ExpectedAddr); |
| CGF.Builder.CreateStore(OldVal, DesiredAddr); |
| } |
| EmitAtomicUpdateValue(CGF, *this, UpdateRVal, DesiredAddr); |
| auto *Res = |
| EmitAtomicCompareExchangeLibcall(ExpectedAddr.getPointer(), |
| DesiredAddr.getPointer(), |
| AO, Failure); |
| CGF.Builder.CreateCondBr(Res, ExitBB, ContBB); |
| CGF.EmitBlock(ExitBB, /*IsFinished=*/true); |
| } |
| |
| void AtomicInfo::EmitAtomicUpdateOp(llvm::AtomicOrdering AO, RValue UpdateRVal, |
| bool IsVolatile) { |
| auto Failure = llvm::AtomicCmpXchgInst::getStrongestFailureOrdering(AO); |
| |
| // Do the atomic load. |
| auto *OldVal = EmitAtomicLoadOp(Failure, IsVolatile); |
| // For non-simple lvalues perform compare-and-swap procedure. |
| auto *ContBB = CGF.createBasicBlock("atomic_cont"); |
| auto *ExitBB = CGF.createBasicBlock("atomic_exit"); |
| auto *CurBB = CGF.Builder.GetInsertBlock(); |
| CGF.EmitBlock(ContBB); |
| llvm::PHINode *PHI = CGF.Builder.CreatePHI(OldVal->getType(), |
| /*NumReservedValues=*/2); |
| PHI->addIncoming(OldVal, CurBB); |
| Address NewAtomicAddr = CreateTempAlloca(); |
| Address NewAtomicIntAddr = emitCastToAtomicIntPointer(NewAtomicAddr); |
| if ((LVal.isBitField() && BFI.Size != ValueSizeInBits) || |
| requiresMemSetZero(getAtomicAddress().getElementType())) { |
| CGF.Builder.CreateStore(PHI, NewAtomicIntAddr); |
| } |
| EmitAtomicUpdateValue(CGF, *this, UpdateRVal, NewAtomicAddr); |
| auto *DesiredVal = CGF.Builder.CreateLoad(NewAtomicIntAddr); |
| // Try to write new value using cmpxchg operation. |
| auto Res = EmitAtomicCompareExchangeOp(PHI, DesiredVal, AO, Failure); |
| PHI->addIncoming(Res.first, CGF.Builder.GetInsertBlock()); |
| CGF.Builder.CreateCondBr(Res.second, ExitBB, ContBB); |
| CGF.EmitBlock(ExitBB, /*IsFinished=*/true); |
| } |
| |
| void AtomicInfo::EmitAtomicUpdate( |
| llvm::AtomicOrdering AO, const llvm::function_ref<RValue(RValue)> &UpdateOp, |
| bool IsVolatile) { |
| if (shouldUseLibcall()) { |
| EmitAtomicUpdateLibcall(AO, UpdateOp, IsVolatile); |
| } else { |
| EmitAtomicUpdateOp(AO, UpdateOp, IsVolatile); |
| } |
| } |
| |
| void AtomicInfo::EmitAtomicUpdate(llvm::AtomicOrdering AO, RValue UpdateRVal, |
| bool IsVolatile) { |
| if (shouldUseLibcall()) { |
| EmitAtomicUpdateLibcall(AO, UpdateRVal, IsVolatile); |
| } else { |
| EmitAtomicUpdateOp(AO, UpdateRVal, IsVolatile); |
| } |
| } |
| |
| void CodeGenFunction::EmitAtomicStore(RValue rvalue, LValue lvalue, |
| bool isInit) { |
| bool IsVolatile = lvalue.isVolatileQualified(); |
| llvm::AtomicOrdering AO; |
| if (lvalue.getType()->isAtomicType()) { |
| AO = llvm::AtomicOrdering::SequentiallyConsistent; |
| } else { |
| AO = llvm::AtomicOrdering::Release; |
| IsVolatile = true; |
| } |
| return EmitAtomicStore(rvalue, lvalue, AO, IsVolatile, isInit); |
| } |
| |
| /// Emit a store to an l-value of atomic type. |
| /// |
| /// Note that the r-value is expected to be an r-value *of the atomic |
| /// type*; this means that for aggregate r-values, it should include |
| /// storage for any padding that was necessary. |
| void CodeGenFunction::EmitAtomicStore(RValue rvalue, LValue dest, |
| llvm::AtomicOrdering AO, bool IsVolatile, |
| bool isInit) { |
| // If this is an aggregate r-value, it should agree in type except |
| // maybe for address-space qualification. |
| assert(!rvalue.isAggregate() || |
| rvalue.getAggregateAddress().getElementType() == |
| dest.getAddress(*this).getElementType()); |
| |
| AtomicInfo atomics(*this, dest); |
| LValue LVal = atomics.getAtomicLValue(); |
| |
| // If this is an initialization, just put the value there normally. |
| if (LVal.isSimple()) { |
| if (isInit) { |
| atomics.emitCopyIntoMemory(rvalue); |
| return; |
| } |
| |
| // Check whether we should use a library call. |
| if (atomics.shouldUseLibcall()) { |
| // Produce a source address. |
| Address srcAddr = atomics.materializeRValue(rvalue); |
| |
| // void __atomic_store(size_t size, void *mem, void *val, int order) |
| CallArgList args; |
| args.add(RValue::get(atomics.getAtomicSizeValue()), |
| getContext().getSizeType()); |
| args.add(RValue::get(EmitCastToVoidPtr(atomics.getAtomicPointer())), |
| getContext().VoidPtrTy); |
| args.add(RValue::get(EmitCastToVoidPtr(srcAddr.getPointer())), |
| getContext().VoidPtrTy); |
| args.add( |
| RValue::get(llvm::ConstantInt::get(IntTy, (int)llvm::toCABI(AO))), |
| getContext().IntTy); |
| emitAtomicLibcall(*this, "__atomic_store", getContext().VoidTy, args); |
| return; |
| } |
| |
| // Okay, we're doing this natively. |
| llvm::Value *intValue = atomics.convertRValueToInt(rvalue); |
| |
| // Do the atomic store. |
| Address addr = |
| atomics.emitCastToAtomicIntPointer(atomics.getAtomicAddress()); |
| intValue = Builder.CreateIntCast( |
| intValue, addr.getElementType(), /*isSigned=*/false); |
| llvm::StoreInst *store = Builder.CreateStore(intValue, addr); |
| |
| if (AO == llvm::AtomicOrdering::Acquire) |
| AO = llvm::AtomicOrdering::Monotonic; |
| else if (AO == llvm::AtomicOrdering::AcquireRelease) |
| AO = llvm::AtomicOrdering::Release; |
| // Initializations don't need to be atomic. |
| if (!isInit) |
| store->setAtomic(AO); |
| |
| // Other decoration. |
| if (IsVolatile) |
| store->setVolatile(true); |
| CGM.DecorateInstructionWithTBAA(store, dest.getTBAAInfo()); |
| return; |
| } |
| |
| // Emit simple atomic update operation. |
| atomics.EmitAtomicUpdate(AO, rvalue, IsVolatile); |
| } |
| |
| /// Emit a compare-and-exchange op for atomic type. |
| /// |
| std::pair<RValue, llvm::Value *> CodeGenFunction::EmitAtomicCompareExchange( |
| LValue Obj, RValue Expected, RValue Desired, SourceLocation Loc, |
| llvm::AtomicOrdering Success, llvm::AtomicOrdering Failure, bool IsWeak, |
| AggValueSlot Slot) { |
| // If this is an aggregate r-value, it should agree in type except |
| // maybe for address-space qualification. |
| assert(!Expected.isAggregate() || |
| Expected.getAggregateAddress().getElementType() == |
| Obj.getAddress(*this).getElementType()); |
| assert(!Desired.isAggregate() || |
| Desired.getAggregateAddress().getElementType() == |
| Obj.getAddress(*this).getElementType()); |
| AtomicInfo Atomics(*this, Obj); |
| |
| return Atomics.EmitAtomicCompareExchange(Expected, Desired, Success, Failure, |
| IsWeak); |
| } |
| |
| void CodeGenFunction::EmitAtomicUpdate( |
| LValue LVal, llvm::AtomicOrdering AO, |
| const llvm::function_ref<RValue(RValue)> &UpdateOp, bool IsVolatile) { |
| AtomicInfo Atomics(*this, LVal); |
| Atomics.EmitAtomicUpdate(AO, UpdateOp, IsVolatile); |
| } |
| |
| void CodeGenFunction::EmitAtomicInit(Expr *init, LValue dest) { |
| AtomicInfo atomics(*this, dest); |
| |
| switch (atomics.getEvaluationKind()) { |
| case TEK_Scalar: { |
| llvm::Value *value = EmitScalarExpr(init); |
| atomics.emitCopyIntoMemory(RValue::get(value)); |
| return; |
| } |
| |
| case TEK_Complex: { |
| ComplexPairTy value = EmitComplexExpr(init); |
| atomics.emitCopyIntoMemory(RValue::getComplex(value)); |
| return; |
| } |
| |
| case TEK_Aggregate: { |
| // Fix up the destination if the initializer isn't an expression |
| // of atomic type. |
| bool Zeroed = false; |
| if (!init->getType()->isAtomicType()) { |
| Zeroed = atomics.emitMemSetZeroIfNecessary(); |
| dest = atomics.projectValue(); |
| } |
| |
| // Evaluate the expression directly into the destination. |
| AggValueSlot slot = AggValueSlot::forLValue( |
| dest, *this, AggValueSlot::IsNotDestructed, |
| AggValueSlot::DoesNotNeedGCBarriers, AggValueSlot::IsNotAliased, |
| AggValueSlot::DoesNotOverlap, |
| Zeroed ? AggValueSlot::IsZeroed : AggValueSlot::IsNotZeroed); |
| |
| EmitAggExpr(init, slot); |
| return; |
| } |
| } |
| llvm_unreachable("bad evaluation kind"); |
| } |