llvm::CallLowering Class Reference

#include "llvm/CodeGen/GlobalISel/CallLowering.h"

Inheritance diagram for llvm::CallLowering:

Classes
struct	ArgInfo
struct	BaseArgInfo
struct	CallLoweringInfo
struct	IncomingValueAssigner
struct	IncomingValueHandler
	Base class for ValueHandlers used for arguments coming into the current function, or for return values received from a call. More...
struct	OutgoingValueAssigner
struct	OutgoingValueHandler
	Base class for ValueHandlers used for arguments passed to a function call, or for return values. More...
struct	PtrAuthInfo
struct	ValueAssigner
	Argument handling is mostly uniform between the four places that make these decisions: function formal arguments, call instruction args, call instruction returns and function returns. More...
struct	ValueHandler

Public Member Functions
	CallLowering (const TargetLowering *TLI)
virtual	~CallLowering ()=default
virtual bool	supportSwiftError () const
void	insertSRetLoads (MachineIRBuilder &MIRBuilder, Type *RetTy, ArrayRef< Register > VRegs, Register DemoteReg, int FI) const
	Load the returned value from the stack into virtual registers in VRegs.
void	insertSRetStores (MachineIRBuilder &MIRBuilder, Type *RetTy, ArrayRef< Register > VRegs, Register DemoteReg) const
	Store the return value given by VRegs into stack starting at the offset specified in DemoteReg.
void	insertSRetIncomingArgument (const Function &F, SmallVectorImpl< ArgInfo > &SplitArgs, Register &DemoteReg, MachineRegisterInfo &MRI, const DataLayout &DL) const
	Insert the hidden sret ArgInfo to the beginning of SplitArgs.
void	insertSRetOutgoingArgument (MachineIRBuilder &MIRBuilder, const CallBase &CB, CallLoweringInfo &Info) const
	For the call-base described by CB, insert the hidden sret ArgInfo to the OrigArgs field of Info.
bool	checkReturn (CCState &CCInfo, SmallVectorImpl< BaseArgInfo > &Outs, CCAssignFn *Fn) const
void	getReturnInfo (CallingConv::ID CallConv, Type *RetTy, AttributeList Attrs, SmallVectorImpl< BaseArgInfo > &Outs, const DataLayout &DL) const
	Get the type and the ArgFlags for the split components of RetTy as returned by ComputeValueVTs.
bool	checkReturnTypeForCallConv (MachineFunction &MF) const
	Toplevel function to check the return type based on the target calling convention.
virtual bool	canLowerReturn (MachineFunction &MF, CallingConv::ID CallConv, SmallVectorImpl< BaseArgInfo > &Outs, bool IsVarArg) const
	This hook must be implemented to check whether the return values described by Outs can fit into the return registers.
virtual bool	lowerReturn (MachineIRBuilder &MIRBuilder, const Value *Val, ArrayRef< Register > VRegs, FunctionLoweringInfo &FLI, Register SwiftErrorVReg) const
	This hook must be implemented to lower outgoing return values, described by Val, into the specified virtual registers VRegs.
virtual bool	lowerReturn (MachineIRBuilder &MIRBuilder, const Value *Val, ArrayRef< Register > VRegs, FunctionLoweringInfo &FLI) const
	This hook behaves as the extended lowerReturn function, but for targets that do not support swifterror value promotion.
virtual bool	fallBackToDAGISel (const MachineFunction &MF) const
virtual bool	lowerFormalArguments (MachineIRBuilder &MIRBuilder, const Function &F, ArrayRef< ArrayRef< Register > > VRegs, FunctionLoweringInfo &FLI) const
	This hook must be implemented to lower the incoming (formal) arguments, described by VRegs, for GlobalISel.
virtual bool	lowerCall (MachineIRBuilder &MIRBuilder, CallLoweringInfo &Info) const
	This hook must be implemented to lower the given call instruction, including argument and return value marshalling.
bool	lowerCall (MachineIRBuilder &MIRBuilder, const CallBase &Call, ArrayRef< Register > ResRegs, ArrayRef< ArrayRef< Register > > ArgRegs, Register SwiftErrorVReg, std::optional< PtrAuthInfo > PAI, Register ConvergenceCtrlToken, std::function< unsigned()> GetCalleeReg) const
	Lower the given call instruction, including argument and return value marshalling.
virtual bool	enableBigEndian () const
	For targets which want to use big-endian can enable it with enableBigEndian() hook.
virtual bool	isTypeIsValidForThisReturn (EVT Ty) const
	For targets which support the "returned" parameter attribute, returns true if the given type is a valid one to use with "returned".

Protected Member Functions
const TargetLowering *	getTLI () const
	Getter for generic TargetLowering class.
template<class XXXTargetLowering >
const XXXTargetLowering *	getTLI () const
	Getter for target specific TargetLowering class.
ISD::ArgFlagsTy	getAttributesForArgIdx (const CallBase &Call, unsigned ArgIdx) const
ISD::ArgFlagsTy	getAttributesForReturn (const CallBase &Call) const
void	addArgFlagsFromAttributes (ISD::ArgFlagsTy &Flags, const AttributeList &Attrs, unsigned OpIdx) const
	Adds flags to Flags based off of the attributes in Attrs.
template<typename FuncInfoTy >
void	setArgFlags (ArgInfo &Arg, unsigned OpIdx, const DataLayout &DL, const FuncInfoTy &FuncInfo) const
void	splitToValueTypes (const ArgInfo &OrigArgInfo, SmallVectorImpl< ArgInfo > &SplitArgs, const DataLayout &DL, CallingConv::ID CallConv, SmallVectorImpl< uint64_t > *Offsets=nullptr) const
	Break OrigArgInfo into one or more pieces the calling convention can process, returned in SplitArgs.
bool	determineAssignments (ValueAssigner &Assigner, SmallVectorImpl< ArgInfo > &Args, CCState &CCInfo) const
	Analyze the argument list in Args, using Assigner to populate CCInfo.
bool	determineAndHandleAssignments (ValueHandler &Handler, ValueAssigner &Assigner, SmallVectorImpl< ArgInfo > &Args, MachineIRBuilder &MIRBuilder, CallingConv::ID CallConv, bool IsVarArg, ArrayRef< Register > ThisReturnRegs=std::nullopt) const
	Invoke ValueAssigner::assignArg on each of the given Args and then use Handler to move them to the assigned locations.
bool	handleAssignments (ValueHandler &Handler, SmallVectorImpl< ArgInfo > &Args, CCState &CCState, SmallVectorImpl< CCValAssign > &ArgLocs, MachineIRBuilder &MIRBuilder, ArrayRef< Register > ThisReturnRegs=std::nullopt) const
	Use Handler to insert code to handle the argument/return values represented by Args.
bool	parametersInCSRMatch (const MachineRegisterInfo &MRI, const uint32_t *CallerPreservedMask, const SmallVectorImpl< CCValAssign > &ArgLocs, const SmallVectorImpl< ArgInfo > &OutVals) const
	Check whether parameters to a call that are passed in callee saved registers are the same as from the calling function.
bool	resultsCompatible (CallLoweringInfo &Info, MachineFunction &MF, SmallVectorImpl< ArgInfo > &InArgs, ValueAssigner &CalleeAssigner, ValueAssigner &CallerAssigner) const

Detailed Description

Definition at line 44 of file CallLowering.h.

Constructor & Destructor Documentation

CallLowering()

llvm::CallLowering::CallLowering ( const TargetLowering *  TLI )

inline

Definition at line 451 of file CallLowering.h.

~CallLowering()

virtual llvm::CallLowering::~CallLowering ( )

virtualdefault

Member Function Documentation

addArgFlagsFromAttributes()

void CallLowering::addArgFlagsFromAttributes ( ISD::ArgFlagsTy &  Flags, const AttributeList &  Attrs, unsigned  OpIdx  ) const

protected

Adds flags to Flags based off of the attributes in Attrs.

OpIdx is the index in Attrs to add flags from.

Definition at line 86 of file CallLowering.cpp.

References addFlagsUsingAttrFn().

Referenced by getReturnInfo(), and setArgFlags().

canLowerReturn()

virtual bool llvm::CallLowering::canLowerReturn ( MachineFunction &  MF, CallingConv::ID  CallConv, SmallVectorImpl< BaseArgInfo > &  Outs, bool  IsVarArg  ) const

inlinevirtual

This hook must be implemented to check whether the return values described by Outs can fit into the return registers.

If false is returned, an sret-demotion is performed.

Reimplemented in llvm::AArch64CallLowering, and llvm::X86CallLowering.

Definition at line 506 of file CallLowering.h.

Referenced by checkReturnTypeForCallConv(), and lowerCall().

checkReturn()

bool CallLowering::checkReturn	(	CCState &	CCInfo,
		SmallVectorImpl< BaseArgInfo > &	Outs,
		CCAssignFn *	Fn
	)		const

Returns

True if the return type described by Outs can be returned without performing sret demotion.

Definition at line 1095 of file CallLowering.cpp.

References llvm::CCValAssign::Full, llvm::MVT::getVT(), I, and llvm::SmallVectorBase< Size_T >::size().

Referenced by llvm::AArch64CallLowering::canLowerReturn(), and llvm::X86CallLowering::canLowerReturn().

checkReturnTypeForCallConv()

bool CallLowering::checkReturnTypeForCallConv

(

MachineFunction &

MF

)

const

Toplevel function to check the return type based on the target calling convention.

Returns

True if the return value of MF can be returned without performing sret demotion.

Definition at line 1129 of file CallLowering.cpp.

References canLowerReturn(), F, llvm::MachineFunction::getDataLayout(), llvm::MachineFunction::getFunction(), and getReturnInfo().

Referenced by llvm::IRTranslator::runOnMachineFunction().

determineAndHandleAssignments()

bool CallLowering::determineAndHandleAssignments ( ValueHandler &  Handler, ValueAssigner &  Assigner, SmallVectorImpl< ArgInfo > &  Args, MachineIRBuilder &  MIRBuilder, CallingConv::ID  CallConv, bool  IsVarArg, ArrayRef< Register >  ThisReturnRegs = std::nullopt  ) const

protected

Invoke ValueAssigner::assignArg on each of the given Args and then use Handler to move them to the assigned locations.

Returns

True if everything has succeeded, false otherwise.

Definition at line 649 of file CallLowering.cpp.

References determineAssignments(), F, llvm::MachineFunction::getFunction(), llvm::MachineIRBuilder::getMF(), and handleAssignments().

Referenced by llvm::AArch64CallLowering::lowerCall(), llvm::AMDGPUCallLowering::lowerCall(), llvm::ARMCallLowering::lowerCall(), llvm::M68kCallLowering::lowerCall(), llvm::RISCVCallLowering::lowerCall(), llvm::X86CallLowering::lowerCall(), llvm::ARMCallLowering::lowerFormalArguments(), llvm::M68kCallLowering::lowerFormalArguments(), llvm::PPCCallLowering::lowerFormalArguments(), llvm::X86CallLowering::lowerFormalArguments(), llvm::X86CallLowering::lowerReturn(), llvm::AArch64CallLowering::lowerReturn(), llvm::M68kCallLowering::lowerReturn(), and llvm::PPCCallLowering::lowerReturn().

determineAssignments()

bool CallLowering::determineAssignments ( ValueAssigner &  Assigner, SmallVectorImpl< ArgInfo > &  Args, CCState &  CCInfo  ) const

protected

Analyze the argument list in Args, using Assigner to populate CCInfo.

This will determine the types and locations to use for passed or returned values. This may resize fields in Args if the value is split across multiple registers or stack slots.

This is independent of the function state and can be used to determine how a call would pass arguments without needing to change the function. This can be used to check if arguments are suitable for tail call lowering.

Returns

True if everything has succeeded, false otherwise.

Definition at line 674 of file CallLowering.cpp.

References llvm::CallLowering::ValueAssigner::assignArg(), llvm::CCValAssign::Full, llvm::CCState::getCallingConv(), llvm::CCState::getContext(), llvm::EVT::getEVT(), llvm::TargetLoweringBase::getNumRegistersForCallingConv(), and llvm::TargetLoweringBase::getRegisterTypeForCallingConv().

Referenced by llvm::AMDGPUCallLowering::areCalleeOutgoingArgsTailCallable(), determineAndHandleAssignments(), llvm::AMDGPUCallLowering::lowerCall(), llvm::MipsCallLowering::lowerCall(), llvm::AMDGPUCallLowering::lowerFormalArguments(), llvm::AArch64CallLowering::lowerFormalArguments(), llvm::MipsCallLowering::lowerFormalArguments(), llvm::RISCVCallLowering::lowerFormalArguments(), llvm::MipsCallLowering::lowerReturn(), llvm::AMDGPUCallLowering::lowerTailCall(), and resultsCompatible().

enableBigEndian()

virtual bool llvm::CallLowering::enableBigEndian ( ) const

inlinevirtual

For targets which want to use big-endian can enable it with enableBigEndian() hook.

Reimplemented in llvm::ARMCallLowering, and llvm::M68kCallLowering.

Definition at line 603 of file CallLowering.h.

Referenced by llvm::IRTranslator::runOnMachineFunction().

fallBackToDAGISel()

virtual bool llvm::CallLowering::fallBackToDAGISel ( const MachineFunction &  MF ) const

inlinevirtual

Reimplemented in llvm::AArch64CallLowering.

Definition at line 540 of file CallLowering.h.

Referenced by llvm::IRTranslator::runOnMachineFunction().

getAttributesForArgIdx()

ISD::ArgFlagsTy CallLowering::getAttributesForArgIdx ( const CallBase &  Call, unsigned  ArgIdx  ) const

protected

Returns

Flags corresponding to the attributes on the ArgIdx-th parameter of Call.

Definition at line 68 of file CallLowering.cpp.

References addFlagsUsingAttrFn().

Referenced by lowerCall().

getAttributesForReturn()

ISD::ArgFlagsTy CallLowering::getAttributesForReturn ( const CallBase &  Call ) const

protected

Returns

Flags corresponding to the attributes on the return from Call.

Definition at line 78 of file CallLowering.cpp.

References addFlagsUsingAttrFn().

Referenced by lowerCall().

getReturnInfo()

void CallLowering::getReturnInfo	(	CallingConv::ID	CallConv,
		Type *	RetTy,
		AttributeList	Attrs,
		SmallVectorImpl< BaseArgInfo > &	Outs,
		const DataLayout &	DL
	)		const

Get the type and the ArgFlags for the split components of RetTy as returned by ComputeValueVTs.

Definition at line 1106 of file CallLowering.cpp.

References addArgFlagsFromAttributes(), llvm::ComputeValueVTs(), DL, llvm::SmallVectorImpl< T >::emplace_back(), llvm::TargetLoweringBase::getNumRegistersForCallingConv(), llvm::TargetLoweringBase::getRegisterTypeForCallingConv(), llvm::EVT::getTypeForEVT(), I, RetTy, and llvm::AttributeList::ReturnIndex.

Referenced by checkReturnTypeForCallConv(), and lowerCall().

getTLI() [1/2]

const TargetLowering * llvm::CallLowering::getTLI ( ) const

inlineprotected

Getter for generic TargetLowering class.

Definition at line 354 of file CallLowering.h.

Referenced by setArgFlags().

getTLI() [2/2]

template<class XXXTargetLowering >

const XXXTargetLowering * llvm::CallLowering::getTLI ( ) const

inlineprotected

Getter for target specific TargetLowering class.

Definition at line 360 of file CallLowering.h.

handleAssignments()

bool CallLowering::handleAssignments ( ValueHandler &  Handler, SmallVectorImpl< ArgInfo > &  Args, CCState &  CCState, SmallVectorImpl< CCValAssign > &  ArgLocs, MachineIRBuilder &  MIRBuilder, ArrayRef< Register >  ThisReturnRegs = std::nullopt  ) const

protected

Use Handler to insert code to handle the argument/return values represented by Args.

It's expected determineAssignments previously processed these arguments to populate CCState and ArgLocs.

Definition at line 735 of file CallLowering.cpp.

References assert(), llvm::CallLowering::ValueHandler::assignCustomValue(), llvm::CallLowering::ValueHandler::assignValueToAddress(), llvm::CallLowering::ValueHandler::assignValueToReg(), llvm::MachineIRBuilder::buildCopy(), buildCopyFromRegs(), buildCopyToRegs(), llvm::MachineIRBuilder::buildFrameIndex(), llvm::MachineIRBuilder::buildLoad(), llvm::MachineIRBuilder::buildStore(), llvm::CallLowering::ValueHandler::copyArgumentMemory(), llvm::MachineFrameInfo::CreateStackObject(), DL, llvm::ArrayRef< T >::empty(), extendOpFromFlags(), F, llvm::LLT::getAddressSpace(), llvm::DataLayout::getAllocaAddrSpace(), llvm::MachineFunction::getDataLayout(), llvm::EVT::getEVT(), llvm::MachinePointerInfo::getFixedStack(), llvm::MachineFunction::getFrameInfo(), llvm::MachineFunction::getFunction(), llvm::getLLTForType(), llvm::CCValAssign::getLocInfo(), llvm::CCValAssign::getLocMemOffset(), llvm::CCValAssign::getLocReg(), llvm::CCValAssign::getLocVT(), llvm::MachineIRBuilder::getMF(), llvm::MachineInstrBuilder::getReg(), llvm::MachineFunction::getRegInfo(), llvm::LLT::getScalarSizeInBits(), llvm::LLT::getSizeInBytes(), llvm::CallLowering::ValueHandler::getStackAddress(), llvm::CallLowering::ValueHandler::getStackValueStoreType(), llvm::MachinePointerInfo::getUnknownStack(), llvm::CCValAssign::getValNo(), llvm::CCValAssign::getValVT(), llvm::TargetLoweringBase::hasBigEndianPartOrdering(), Idx, llvm::CCValAssign::Indirect, llvm::inferAlignFromPtrInfo(), llvm::CallLowering::ValueHandler::isIncomingArgumentHandler(), llvm::CCValAssign::isMemLoc(), isTypeIsValidForThisReturn(), MRI, llvm::CCValAssign::needsCustom(), llvm::Offset, llvm::LLT::pointer(), and llvm::SmallVectorBase< Size_T >::size().

Referenced by determineAndHandleAssignments(), llvm::AMDGPUCallLowering::lowerCall(), llvm::MipsCallLowering::lowerCall(), llvm::AMDGPUCallLowering::lowerFormalArguments(), llvm::AArch64CallLowering::lowerFormalArguments(), llvm::MipsCallLowering::lowerFormalArguments(), llvm::RISCVCallLowering::lowerFormalArguments(), llvm::MipsCallLowering::lowerReturn(), and llvm::AMDGPUCallLowering::lowerTailCall().

insertSRetIncomingArgument()

void CallLowering::insertSRetIncomingArgument	(	const Function &	F,
		SmallVectorImpl< ArgInfo > &	SplitArgs,
		Register &	DemoteReg,
		MachineRegisterInfo &	MRI,
		const DataLayout &	DL
	)		const

Insert the hidden sret ArgInfo to the beginning of SplitArgs.

This function should be called from the target specific lowerFormalArguments when F requires the sret demotion.

Definition at line 1051 of file CallLowering.cpp.

References assert(), llvm::SmallVectorTemplateCommon< T, typename >::begin(), llvm::ComputeValueVTs(), DL, F, llvm::CallLowering::BaseArgInfo::Flags, llvm::PointerType::get(), llvm::Type::getContext(), llvm::SmallVectorImpl< T >::insert(), MRI, llvm::CallLowering::ArgInfo::NoArgIndex, llvm::LLT::pointer(), llvm::AttributeList::ReturnIndex, setArgFlags(), and llvm::SmallVectorBase< Size_T >::size().

Referenced by llvm::AMDGPUCallLowering::lowerFormalArguments(), llvm::AArch64CallLowering::lowerFormalArguments(), and llvm::X86CallLowering::lowerFormalArguments().

insertSRetLoads()

void CallLowering::insertSRetLoads	(	MachineIRBuilder &	MIRBuilder,
		Type *	RetTy,
		ArrayRef< Register >	VRegs,
		Register	DemoteReg,
		int	FI
	)		const

Load the returned value from the stack into virtual registers in VRegs.

It uses the frame index FI and the start offset from DemoteReg. The loaded data size will be determined from RetTy.

Definition at line 990 of file CallLowering.cpp.

References Addr, assert(), llvm::MachineIRBuilder::buildLoad(), llvm::commonAlignment(), llvm::ComputeValueVTs(), DL, llvm::PointerType::get(), llvm::MachineFunction::getDataLayout(), llvm::MachinePointerInfo::getFixedStack(), llvm::getLLTForType(), llvm::MachineFunction::getMachineMemOperand(), llvm::MachineIRBuilder::getMF(), llvm::MachineFunction::getRegInfo(), I, llvm::MachineIRBuilder::materializePtrAdd(), llvm::MachineMemOperand::MOLoad, MRI, RetTy, llvm::ArrayRef< T >::size(), and llvm::SmallVectorBase< Size_T >::size().

Referenced by llvm::AArch64CallLowering::lowerCall(), llvm::AMDGPUCallLowering::lowerCall(), and llvm::X86CallLowering::lowerCall().

insertSRetOutgoingArgument()

void CallLowering::insertSRetOutgoingArgument	(	MachineIRBuilder &	MIRBuilder,
		const CallBase &	CB,
		CallLoweringInfo &	Info
	)		const

For the call-base described by CB, insert the hidden sret ArgInfo to the OrigArgs field of Info.

Definition at line 1073 of file CallLowering.cpp.

References llvm::MachineIRBuilder::buildFrameIndex(), llvm::MachineFrameInfo::CreateStackObject(), DL, llvm::CallLowering::BaseArgInfo::Flags, llvm::PointerType::get(), llvm::MachineIRBuilder::getDataLayout(), llvm::MachineFunction::getFrameInfo(), llvm::MachineIRBuilder::getMF(), llvm::MachineInstrBuilder::getReg(), llvm::Value::getType(), Info, llvm::CallLowering::ArgInfo::NoArgIndex, llvm::LLT::pointer(), RetTy, llvm::AttributeList::ReturnIndex, and setArgFlags().

Referenced by lowerCall().

insertSRetStores()

void CallLowering::insertSRetStores	(	MachineIRBuilder &	MIRBuilder,
		Type *	RetTy,
		ArrayRef< Register >	VRegs,
		Register	DemoteReg
	)		const

Store the return value given by VRegs into stack starting at the offset specified in DemoteReg.

Definition at line 1021 of file CallLowering.cpp.

References Addr, assert(), llvm::MachineIRBuilder::buildStore(), llvm::commonAlignment(), llvm::ComputeValueVTs(), DL, llvm::MachineFunction::getDataLayout(), llvm::getLLTForType(), llvm::MachineFunction::getMachineMemOperand(), llvm::MachineIRBuilder::getMF(), llvm::MachineFunction::getRegInfo(), I, llvm::MachineIRBuilder::materializePtrAdd(), llvm::MachineMemOperand::MOStore, MRI, RetTy, llvm::ArrayRef< T >::size(), and llvm::SmallVectorBase< Size_T >::size().

Referenced by llvm::AMDGPUCallLowering::lowerReturn(), llvm::X86CallLowering::lowerReturn(), and llvm::AArch64CallLowering::lowerReturn().

isTypeIsValidForThisReturn()

virtual bool llvm::CallLowering::isTypeIsValidForThisReturn ( EVT  Ty ) const

inlinevirtual

For targets which support the "returned" parameter attribute, returns true if the given type is a valid one to use with "returned".

Reimplemented in llvm::AArch64CallLowering.

Definition at line 607 of file CallLowering.h.

Referenced by handleAssignments().

lowerCall() [1/2]

virtual bool llvm::CallLowering::lowerCall ( MachineIRBuilder &  MIRBuilder, CallLoweringInfo &  Info  ) const

inlinevirtual

This hook must be implemented to lower the given call instruction, including argument and return value marshalling.

Returns

true if the lowering succeeded, false otherwise.

Reimplemented in llvm::AArch64CallLowering, llvm::AMDGPUCallLowering, llvm::ARMCallLowering, llvm::BPFCallLowering, llvm::M68kCallLowering, llvm::MipsCallLowering, llvm::PPCCallLowering, llvm::RISCVCallLowering, llvm::SPIRVCallLowering, and llvm::X86CallLowering.

Definition at line 566 of file CallLowering.h.

Referenced by lowerCall().

lowerCall() [2/2]

bool CallLowering::lowerCall	(	MachineIRBuilder &	MIRBuilder,
		const CallBase &	Call,
		ArrayRef< Register >	ResRegs,
		ArrayRef< ArrayRef< Register > >	ArgRegs,
		Register	SwiftErrorVReg,
		std::optional< PtrAuthInfo >	PAI,
		Register	ConvergenceCtrlToken,
		std::function< unsigned()>	GetCalleeReg
	)		const

Lower the given call instruction, including argument and return value marshalling.

CI is the call/invoke instruction.

ResRegs are the registers where the call's return value should be stored (or 0 if there is no return value). There will be one register for each non-aggregate type, as returned by computeValueLLTs.

ArgRegs is a list of lists of virtual registers containing each argument that needs to be passed (argument i should be placed in ArgRegs[i]). For each argument, there will be one register for each non-aggregate type, as returned by computeValueLLTs.

SwiftErrorVReg is non-zero if the call has a swifterror inout parameter, and contains the vreg that the swifterror should be copied into after the call.

GetCalleeReg is a callback to materialize a register for the callee if the target determines it cannot jump to the destination based purely on CI. This might be because CI is indirect, or because of the limited range of an immediate jump.

Returns

true if the lowering succeeded, false otherwise.

Definition at line 94 of file CallLowering.cpp.

References llvm::CallBase::args(), assert(), llvm::MachineIRBuilder::buildAssertAlign(), llvm::MachineIRBuilder::buildGlobalValue(), canLowerReturn(), llvm::CallBase::countOperandBundlesOfType(), llvm::MachineOperand::CreateGA(), llvm::MachineOperand::CreateReg(), DL, F, llvm::AttributeList::FirstArgIndex, llvm::CallBase::getAttributes(), getAttributesForArgIdx(), getAttributesForReturn(), llvm::CallBase::getCalledOperand(), llvm::CallBase::getCallingConv(), llvm::MachineIRBuilder::getDataLayout(), llvm::Function::getFnAttribute(), llvm::MachineFunction::getFunction(), llvm::CallBase::getFunctionType(), llvm::getLLTForType(), llvm::Instruction::getMetadata(), llvm::MachineIRBuilder::getMF(), llvm::FunctionType::getNumParams(), llvm::CallBase::getOperandBundle(), llvm::MachineInstrBuilder::getReg(), llvm::MachineFunction::getRegInfo(), llvm::CallBase::getRetAlign(), getReturnInfo(), llvm::MachineFunction::getTarget(), llvm::Value::getType(), llvm::Attribute::getValueAsString(), Info, insertSRetOutgoingArgument(), llvm::CallBase::isConvergent(), llvm::CallBase::isIndirectCall(), llvm::isInTailCallPosition(), llvm::CallBase::isMustTailCall(), llvm::CallBase::isTailCall(), llvm::FunctionType::isVarArg(), lowerCall(), MRI, NumFixedArgs, llvm::LLVMContext::OB_kcfi, llvm::LLVMContext::OB_ptrauth, RetTy, llvm::AttributeList::ReturnIndex, setArgFlags(), and llvm::Value::stripPointerCasts().

lowerFormalArguments()

virtual bool llvm::CallLowering::lowerFormalArguments ( MachineIRBuilder &  MIRBuilder, const Function &  F, ArrayRef< ArrayRef< Register > >  VRegs, FunctionLoweringInfo &  FLI  ) const

inlinevirtual

This hook must be implemented to lower the incoming (formal) arguments, described by VRegs, for GlobalISel.

Each argument must end up in the related virtual registers described by VRegs. In other words, the first argument should end up in VRegs[0], the second in VRegs[1], and so on. For each argument, there will be one register for each non-aggregate type, as returned by computeValueLLTs. MIRBuilder is set to the proper insertion for the argument lowering. FLI is required for sret demotion.

Returns

True if the lowering succeeded, false otherwise.

Reimplemented in llvm::AMDGPUCallLowering, llvm::AArch64CallLowering, llvm::ARMCallLowering, llvm::BPFCallLowering, llvm::M68kCallLowering, llvm::MipsCallLowering, llvm::PPCCallLowering, llvm::RISCVCallLowering, llvm::SPIRVCallLowering, and llvm::X86CallLowering.

Definition at line 554 of file CallLowering.h.

Referenced by llvm::IRTranslator::runOnMachineFunction().

lowerReturn() [1/2]

virtual bool llvm::CallLowering::lowerReturn ( MachineIRBuilder &  MIRBuilder, const Value *  Val, ArrayRef< Register >  VRegs, FunctionLoweringInfo &  FLI  ) const

inlinevirtual

This hook behaves as the extended lowerReturn function, but for targets that do not support swifterror value promotion.

Reimplemented in llvm::AMDGPUCallLowering, llvm::ARMCallLowering, llvm::MipsCallLowering, llvm::X86CallLowering, and llvm::RISCVCallLowering.

Definition at line 534 of file CallLowering.h.

lowerReturn() [2/2]

virtual bool llvm::CallLowering::lowerReturn ( MachineIRBuilder &  MIRBuilder, const Value *  Val, ArrayRef< Register >  VRegs, FunctionLoweringInfo &  FLI, Register  SwiftErrorVReg  ) const

inlinevirtual

This hook must be implemented to lower outgoing return values, described by Val, into the specified virtual registers VRegs.

This hook is used by GlobalISel.

FLI is required for sret demotion.

SwiftErrorVReg is non-zero if the function has a swifterror parameter that needs to be implicitly returned.

Returns

True if the lowering succeeds, false otherwise.

Reimplemented in llvm::AArch64CallLowering, llvm::BPFCallLowering, llvm::M68kCallLowering, llvm::PPCCallLowering, and llvm::SPIRVCallLowering.

Definition at line 522 of file CallLowering.h.

References assert(), lowerReturn(), and supportSwiftError().

Referenced by lowerReturn().

parametersInCSRMatch()

bool CallLowering::parametersInCSRMatch ( const MachineRegisterInfo &  MRI, const uint32_t *  CallerPreservedMask, const SmallVectorImpl< CCValAssign > &  ArgLocs, const SmallVectorImpl< ArgInfo > &  OutVals  ) const

protected

Check whether parameters to a call that are passed in callee saved registers are the same as from the calling function.

This needs to be checked for tail call eligibility.

Definition at line 1140 of file CallLowering.cpp.

References llvm::MachineOperand::clobbersPhysReg(), llvm::dbgs(), llvm::getDefIgnoringCopies(), llvm::MachineInstr::getOpcode(), llvm::MachineInstr::getOperand(), llvm::MachineOperand::getReg(), LLVM_DEBUG, MRI, llvm::CallLowering::ArgInfo::Regs, and llvm::SmallVectorBase< Size_T >::size().

Referenced by llvm::AMDGPUCallLowering::areCalleeOutgoingArgsTailCallable().

resultsCompatible()

bool CallLowering::resultsCompatible ( CallLoweringInfo &  Info, MachineFunction &  MF, SmallVectorImpl< ArgInfo > &  InArgs, ValueAssigner &  CalleeAssigner, ValueAssigner &  CallerAssigner  ) const

protected

Returns

True if the calling convention for a callee and its caller pass results in the same way. Typically used for tail call eligibility checks.

Info is the CallLoweringInfo for the call. MF is the MachineFunction for the caller. InArgs contains the results of the call. CalleeAssigner specifies the target's handling of the argument types for the callee. CallerAssigner specifies the target's handling of the argument types for the caller.

Definition at line 1192 of file CallLowering.cpp.

References determineAssignments(), F, llvm::MachineFunction::getFunction(), llvm::CCValAssign::getLocMemOffset(), llvm::CCValAssign::getLocReg(), Info, llvm::CCValAssign::isRegLoc(), and llvm::SmallVectorBase< Size_T >::size().

Referenced by llvm::AMDGPUCallLowering::doCallerAndCalleePassArgsTheSameWay().

setArgFlags()

template<typename FuncInfoTy >

template void CallLowering::setArgFlags< CallBase > ( ArgInfo &  Arg, unsigned  OpIdx, const DataLayout &  DL, const FuncInfoTy &  FuncInfo  ) const

protected

Definition at line 220 of file CallLowering.cpp.

References addArgFlagsFromAttributes(), assert(), DL, llvm::AttributeList::FirstArgIndex, llvm::CallLowering::BaseArgInfo::Flags, llvm::Type::getPointerAddressSpace(), llvm::Type::getScalarType(), getTLI(), and llvm::CallLowering::BaseArgInfo::Ty.

Referenced by insertSRetIncomingArgument(), insertSRetOutgoingArgument(), lowerCall(), llvm::AMDGPUCallLowering::lowerFormalArguments(), llvm::AArch64CallLowering::lowerFormalArguments(), llvm::ARMCallLowering::lowerFormalArguments(), llvm::M68kCallLowering::lowerFormalArguments(), llvm::MipsCallLowering::lowerFormalArguments(), llvm::PPCCallLowering::lowerFormalArguments(), llvm::RISCVCallLowering::lowerFormalArguments(), llvm::X86CallLowering::lowerFormalArguments(), llvm::AMDGPUCallLowering::lowerFormalArgumentsKernel(), llvm::MipsCallLowering::lowerReturn(), llvm::X86CallLowering::lowerReturn(), llvm::AArch64CallLowering::lowerReturn(), llvm::M68kCallLowering::lowerReturn(), and llvm::PPCCallLowering::lowerReturn().

splitToValueTypes()

void CallLowering::splitToValueTypes ( const ArgInfo &  OrigArgInfo, SmallVectorImpl< ArgInfo > &  SplitArgs, const DataLayout &  DL, CallingConv::ID  CallConv, SmallVectorImpl< uint64_t > *  Offsets = nullptr  ) const

protected

Break OrigArgInfo into one or more pieces the calling convention can process, returned in SplitArgs.

For example, this should break structs down into individual fields.

If Offsets is non-null, it points to a vector to be filled in with the in-memory offsets of each of the individual values.

Definition at line 287 of file CallLowering.cpp.

References assert(), llvm::SmallVectorTemplateCommon< T, typename >::back(), llvm::ComputeValueVTs(), DL, llvm::SmallVectorImpl< T >::emplace_back(), llvm::CallLowering::BaseArgInfo::Flags, llvm::TargetLowering::functionArgumentNeedsConsecutiveRegisters(), llvm::Type::getContext(), llvm::CallLowering::BaseArgInfo::IsFixed, llvm::CallLowering::ArgInfo::OrigArgIndex, llvm::CallLowering::ArgInfo::OrigValue, llvm::CallLowering::ArgInfo::Regs, llvm::SmallVectorBase< Size_T >::size(), and llvm::CallLowering::BaseArgInfo::Ty.

Referenced by llvm::AArch64CallLowering::lowerCall(), llvm::AMDGPUCallLowering::lowerCall(), llvm::ARMCallLowering::lowerCall(), llvm::M68kCallLowering::lowerCall(), llvm::MipsCallLowering::lowerCall(), llvm::RISCVCallLowering::lowerCall(), llvm::X86CallLowering::lowerCall(), llvm::AMDGPUCallLowering::lowerChainCall(), llvm::AMDGPUCallLowering::lowerFormalArguments(), llvm::AArch64CallLowering::lowerFormalArguments(), llvm::ARMCallLowering::lowerFormalArguments(), llvm::M68kCallLowering::lowerFormalArguments(), llvm::MipsCallLowering::lowerFormalArguments(), llvm::PPCCallLowering::lowerFormalArguments(), llvm::RISCVCallLowering::lowerFormalArguments(), llvm::X86CallLowering::lowerFormalArguments(), llvm::MipsCallLowering::lowerReturn(), llvm::X86CallLowering::lowerReturn(), llvm::AArch64CallLowering::lowerReturn(), llvm::M68kCallLowering::lowerReturn(), and llvm::PPCCallLowering::lowerReturn().

supportSwiftError()

virtual bool llvm::CallLowering::supportSwiftError ( ) const

inlinevirtual

Returns

true if the target is capable of handling swifterror values that have been promoted to a specified register. The extended versions of lowerReturn and lowerCall should be implemented.

Reimplemented in llvm::AArch64CallLowering.

Definition at line 457 of file CallLowering.h.

Referenced by lowerReturn().

---

The documentation for this class was generated from the following files:

• include/llvm/CodeGen/GlobalISel/CallLowering.h
• lib/CodeGen/GlobalISel/CallLowering.cpp