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

Inheritance diagram for llvm::GISelValueTracking:

Public Member Functions
	GISelValueTracking (MachineFunction &MF, unsigned MaxDepth=6)

virtual	~GISelValueTracking ()=default

const MachineFunction &	getMachineFunction () const

const DataLayout &	getDataLayout () const

virtual void	computeKnownBitsImpl (Register R, KnownBits &Known, const APInt &DemandedElts, unsigned Depth=0)

unsigned	computeNumSignBits (Register R, const APInt &DemandedElts, unsigned Depth=0)

unsigned	computeNumSignBits (Register R, unsigned Depth=0)

KnownBits	getKnownBits (Register R)

KnownBits	getKnownBits (Register R, const APInt &DemandedElts, unsigned Depth=0)

KnownBits	getKnownBits (MachineInstr &MI)

APInt	getKnownZeroes (Register R)

APInt	getKnownOnes (Register R)

bool	maskedValueIsZero (Register Val, const APInt &Mask)

bool	signBitIsZero (Register Op)

Align	computeKnownAlignment (Register R, unsigned Depth=0)

std::optional< ConstantRange >	getValidShiftAmountRange (Register R, const APInt &DemandedElts, unsigned Depth)
	If a G_SHL/G_ASHR/G_LSHR node with shift operand `R` has shift amounts that are all less than the element bit-width of the shift node, return the valid constant range.

std::optional< uint64_t >	getValidMinimumShiftAmount (Register R, const APInt &DemandedElts, unsigned Depth=0)
	If a G_SHL/G_ASHR/G_LSHR node with shift operand `R` has shift amounts that are all less than the element bit-width of the shift node, return the minimum possible value.

KnownFPClass	computeKnownFPClass (Register R, const APInt &DemandedElts, FPClassTest InterestedClasses, unsigned Depth)
	Determine which floating-point classes are valid for `V`, and return them in KnownFPClass bit sets.

KnownFPClass	computeKnownFPClass (Register R, FPClassTest InterestedClasses=fcAllFlags, unsigned Depth=0)

KnownFPClass	computeKnownFPClass (Register R, const APInt &DemandedElts, uint32_t Flags, FPClassTest InterestedClasses, unsigned Depth)
	Wrapper to account for known fast math flags at the use instruction.

KnownFPClass	computeKnownFPClass (Register R, uint32_t Flags, FPClassTest InterestedClasses, unsigned Depth)

void	erasingInstr (MachineInstr &MI) override
	An instruction is about to be erased.

void	createdInstr (MachineInstr &MI) override
	An instruction has been created and inserted into the function.

void	changingInstr (MachineInstr &MI) override
	This instruction is about to be mutated in some way.

void	changedInstr (MachineInstr &MI) override
	This instruction was mutated in some way.

Public Member Functions inherited from llvm::GISelChangeObserver
virtual	~GISelChangeObserver ()=default

virtual void	erasingInstr (MachineInstr &MI)=0
	An instruction is about to be erased.

virtual void	createdInstr (MachineInstr &MI)=0
	An instruction has been created and inserted into the function.

virtual void	changingInstr (MachineInstr &MI)=0
	This instruction is about to be mutated in some way.

virtual void	changedInstr (MachineInstr &MI)=0
	This instruction was mutated in some way.

LLVM_ABI void	changingAllUsesOfReg (const MachineRegisterInfo &MRI, Register Reg)
	All the instructions using the given register are being changed.

LLVM_ABI void	finishedChangingAllUsesOfReg ()
	All instructions reported as changing by changingAllUsesOfReg() have finished being changed.

Static Public Member Functions
static void	computeKnownBitsForAlignment (KnownBits &Known, Align Alignment)

Protected Member Functions
unsigned	getMaxDepth () const

Detailed Description

Definition at line 34 of file GISelValueTracking.h.

Constructor & Destructor Documentation

◆ GISelValueTracking()

llvm::GISelValueTracking::GISelValueTracking	(	MachineFunction &	MF,
		unsigned	MaxDepth = `6`
	)

◆ ~GISelValueTracking()

virtual llvm::GISelValueTracking::~GISelValueTracking ( )

virtualdefault

Member Function Documentation

◆ changedInstr()

void llvm::GISelValueTracking::changedInstr ( MachineInstr & MI )

inlineoverridevirtual

This instruction was mutated in some way.

Implements llvm::GISelChangeObserver.

Definition at line 152 of file GISelValueTracking.h.

◆ changingInstr()

void llvm::GISelValueTracking::changingInstr ( MachineInstr & MI )

inlineoverridevirtual

This instruction is about to be mutated in some way.

Implements llvm::GISelChangeObserver.

Definition at line 151 of file GISelValueTracking.h.

◆ computeKnownAlignment()

Align GISelValueTracking::computeKnownAlignment	(	Register	R,
		unsigned	Depth = `0`
	)

Returns: The known alignment for the pointer-like value R.

Definition at line 55 of file GISelValueTracking.cpp.

References llvm::TargetLowering::computeKnownAlignForTargetInstr(), computeKnownAlignment(), llvm::Depth, llvm::MachineFunction::getFrameInfo(), llvm::MachineFrameInfo::getObjectAlign(), llvm::MachineRegisterInfo::getVRegDef(), and MI.

Referenced by computeKnownAlignment().

◆ computeKnownBitsForAlignment()

static void llvm::GISelValueTracking::computeKnownBitsForAlignment	(	KnownBits &	Known,
		Align	Alignment
	)

inlinestatic

Definition at line 98 of file GISelValueTracking.h.

References llvm::Log2(), llvm::APInt::setLowBits(), and llvm::KnownBits::Zero.

◆ computeKnownBitsImpl()

void GISelValueTracking::computeKnownBitsImpl	(	Register	R,
		KnownBits &	Known,
		const APInt &	DemandedElts,
		unsigned	Depth = `0`
	)

virtual

Definition at line 163 of file GISelValueTracking.cpp.

References llvm::KnownBits::add(), llvm::KnownBits::anyext(), llvm::KnownBits::anyextOrTrunc(), llvm::KnownBits::ashr(), assert(), llvm::bit_width(), llvm::BitWidth, llvm::KnownBits::byteSwap(), llvm::APInt::clearLowBits(), llvm::TargetLowering::computeKnownBitsForFrameIndex(), llvm::TargetLowering::computeKnownBitsForTargetInstr(), llvm::computeKnownBitsFromRangeMetadata(), computeKnownBitsImpl(), llvm::KnownBits::countMaxLeadingZeros(), llvm::KnownBits::countMaxPopulation(), llvm::dbgs(), llvm::Depth, llvm::drop_begin(), dumpResult(), llvm::enumerate(), llvm::extractBits(), llvm::APInt::extractBits(), llvm::KnownBits::extractBits(), llvm::LLT::getAddressSpace(), llvm::APInt::getAllOnes(), llvm::APInt::getBitWidth(), llvm::KnownBits::getBitWidth(), llvm::TargetLoweringBase::getBooleanContents(), llvm::APInt::getLowBitsSet(), getMaxDepth(), llvm::MachineMemOperand::getMemoryType(), llvm::LLT::getNumElements(), llvm::MachineMemOperand::getRanges(), getReg(), llvm::LLT::getScalarSizeInBits(), llvm::LLT::getScalarType(), llvm::getShuffleDemandedElts(), llvm::LLT::getSizeInBits(), llvm::MachineRegisterInfo::getType(), llvm::MachineRegisterInfo::getVRegDef(), I, Idx, llvm::KnownBits::insertBits(), llvm::KnownBits::intersectWith(), llvm::LLT::isFixedVector(), llvm::DataLayout::isNonIntegralAddressSpace(), llvm::LLT::isScalableVector(), llvm::KnownBits::isUnknown(), llvm::LLT::isValid(), llvm::LLT::isVector(), llvm::Register::isVirtual(), LLVM_DEBUG, llvm::Log2_64(), llvm::KnownBits::lshr(), llvm::KnownBits::makeConstant(), MI, llvm::KnownBits::mul(), llvm::KnownBits::One, llvm::KnownBits::reverseBits(), llvm::APInt::setAllBits(), llvm::APInt::setBitsFrom(), llvm::APInt::setLowBits(), llvm::KnownBits::sext(), llvm::KnownBits::sextInReg(), llvm::KnownBits::shl(), llvm::APInt::shl(), llvm::KnownBits::smax(), llvm::KnownBits::smin(), llvm::KnownBits::sub(), llvm::KnownBits::trunc(), llvm::KnownBits::umax(), llvm::KnownBits::umin(), llvm::KnownBits::Zero, llvm::TargetLoweringBase::ZeroOrOneBooleanContent, llvm::KnownBits::zext(), llvm::APInt::zext(), and llvm::KnownBits::zextOrTrunc().

Referenced by llvm::SITargetLowering::computeKnownBitsForTargetInstr(), computeKnownBitsImpl(), getKnownBits(), and knownBitsForSBFE().

◆ computeKnownFPClass() [1/4]

KnownFPClass GISelValueTracking::computeKnownFPClass	(	Register	R,
		const APInt &	DemandedElts,
		FPClassTest	InterestedClasses,
		unsigned	Depth
	)

Determine which floating-point classes are valid for V, and return them in KnownFPClass bit sets.

This function is defined on values with floating-point type, values vectors of floating-point type, and arrays of floating-point type. InterestedClasses is a compile time optimization hint for which floating point classes should be queried. Queries not specified in InterestedClasses should be reliable if they are determined during the query.

Definition at line 1705 of file GISelValueTracking.cpp.

References llvm::Depth.

◆ computeKnownFPClass() [2/4]

KnownFPClass GISelValueTracking::computeKnownFPClass	(	Register	R,
		const APInt &	DemandedElts,
		uint32_t	Flags,
		FPClassTest	InterestedClasses,
		unsigned	Depth
	)

Wrapper to account for known fast math flags at the use instruction.

Definition at line 1720 of file GISelValueTracking.cpp.

References llvm::Depth, llvm::MachineInstr::FmNoInfs, and llvm::MachineInstr::FmNoNans.

◆ computeKnownFPClass() [3/4]

KnownFPClass GISelValueTracking::computeKnownFPClass	(	Register	R,
		FPClassTest	InterestedClasses = `fcAllFlags`,
		unsigned	Depth = `0`
	)

Definition at line 1713 of file GISelValueTracking.cpp.

References llvm::Depth.

◆ computeKnownFPClass() [4/4]

KnownFPClass GISelValueTracking::computeKnownFPClass	(	Register	R,
		uint32_t	Flags,
		FPClassTest	InterestedClasses,
		unsigned	Depth
	)

Definition at line 1738 of file GISelValueTracking.cpp.

References llvm::Depth, llvm::APInt::getAllOnes(), llvm::LLT::getNumElements(), llvm::MachineRegisterInfo::getType(), and llvm::LLT::isFixedVector().

◆ computeNumSignBits() [1/2]

unsigned GISelValueTracking::computeNumSignBits	(	Register	R,
		const APInt &	DemandedElts,
		unsigned	Depth = `0`
	)

Definition at line 1784 of file GISelValueTracking.cpp.

References llvm::CallingConv::C, computeNumSignBits(), llvm::TargetLowering::computeNumSignBitsForTargetInstr(), computeNumSignBitsFromRangeMetadata(), llvm::Depth, llvm::drop_begin(), llvm::enumerate(), llvm::APInt::extractBits(), llvm::TargetLoweringBase::getBooleanContents(), getDataLayout(), getKnownBits(), getMaxDepth(), llvm::LLT::getNumElements(), llvm::LLT::getScalarSizeInBits(), llvm::getShuffleDemandedElts(), llvm::MachineMemOperand::getSizeInBits(), llvm::LLT::getSizeInBits(), llvm::MachineRegisterInfo::getType(), getValidMinimumShiftAmount(), llvm::LocationSize::getValue(), llvm::MachineRegisterInfo::getVRegDef(), I, llvm::KnownBits::isNegative(), llvm::KnownBits::isNonNegative(), llvm::LLT::isScalableVector(), llvm::LLT::isValid(), llvm::LLT::isVector(), MI, llvm::KnownBits::One, llvm::KnownBits::Zero, llvm::TargetLoweringBase::ZeroOrNegativeOneBooleanContent, and llvm::TargetLoweringBase::ZeroOrOneBooleanContent.

Referenced by computeNumSignBits(), llvm::CombinerHelper::matchAddOverflow(), llvm::CombinerHelper::matchRedundantSExtInReg(), and llvm::LegalizationArtifactCombiner::tryCombineSExt().

◆ computeNumSignBits() [2/2]

unsigned GISelValueTracking::computeNumSignBits	(	Register	R,
		unsigned	Depth = `0`
	)

Definition at line 2057 of file GISelValueTracking.cpp.

References computeNumSignBits(), llvm::Depth, llvm::APInt::getAllOnes(), llvm::LLT::getNumElements(), llvm::MachineRegisterInfo::getType(), and llvm::LLT::isFixedVector().

◆ createdInstr()

void llvm::GISelValueTracking::createdInstr ( MachineInstr & MI )

inlineoverridevirtual

An instruction has been created and inserted into the function.

Note that the instruction might not be a fully fledged instruction at this point and won't be if the MachineFunction::Delegate is calling it. This is because the delegate only sees the construction of the MachineInstr before operands have been added.

Implements llvm::GISelChangeObserver.

Definition at line 150 of file GISelValueTracking.h.

◆ erasingInstr()

void llvm::GISelValueTracking::erasingInstr ( MachineInstr & MI )

inlineoverridevirtual

An instruction is about to be erased.

Implements llvm::GISelChangeObserver.

Definition at line 149 of file GISelValueTracking.h.

◆ getDataLayout()

const DataLayout & llvm::GISelValueTracking::getDataLayout ( ) const

inline

Definition at line 67 of file GISelValueTracking.h.

References DL.

Referenced by computeNumSignBits().

◆ getKnownBits() [1/3]

KnownBits GISelValueTracking::getKnownBits ( MachineInstr & MI )

Definition at line 77 of file GISelValueTracking.cpp.

References assert(), getKnownBits(), and MI.

◆ getKnownBits() [2/3]

KnownBits GISelValueTracking::getKnownBits ( Register R )

Definition at line 83 of file GISelValueTracking.cpp.

References llvm::APInt::getAllOnes(), getKnownBits(), llvm::LLT::getNumElements(), llvm::MachineRegisterInfo::getType(), and llvm::LLT::isFixedVector().

◆ getKnownBits() [3/3]

KnownBits GISelValueTracking::getKnownBits	(	Register	R,
		const APInt &	DemandedElts,
		unsigned	Depth = `0`
	)

Definition at line 93 of file GISelValueTracking.cpp.

References assert(), computeKnownBitsImpl(), and llvm::Depth.

◆ getKnownOnes()

APInt GISelValueTracking::getKnownOnes ( Register R )

Definition at line 115 of file GISelValueTracking.cpp.

References getKnownBits(), and llvm::KnownBits::One.

◆ getKnownZeroes()

APInt GISelValueTracking::getKnownZeroes ( Register R )

Definition at line 111 of file GISelValueTracking.cpp.

References getKnownBits(), and llvm::KnownBits::Zero.

Referenced by llvm::CombinerHelper::matchCombineShlOfExtend(), and llvm::LegalizationArtifactCombiner::tryCombineZExt().

◆ getMachineFunction()

const MachineFunction & llvm::GISelValueTracking::getMachineFunction ( ) const

inline

Definition at line 65 of file GISelValueTracking.h.

Referenced by llvm::SITargetLowering::computeKnownAlignForTargetInstr(), knownBitsForSBFE(), and knownBitsForWorkitemID().

◆ getMaxDepth()

unsigned llvm::GISelValueTracking::getMaxDepth ( ) const

inlineprotected

Definition at line 155 of file GISelValueTracking.h.

Referenced by computeKnownBitsImpl(), and computeNumSignBits().

◆ getValidMinimumShiftAmount()

std::optional< uint64_t > GISelValueTracking::getValidMinimumShiftAmount	(	Register	R,
		const APInt &	DemandedElts,
		unsigned	Depth = `0`
	)

If a G_SHL/G_ASHR/G_LSHR node with shift operand R has shift amounts that are all less than the element bit-width of the shift node, return the minimum possible value.

Definition at line 2114 of file GISelValueTracking.cpp.

References llvm::Depth, and getValidShiftAmountRange().

Referenced by computeNumSignBits().

◆ getValidShiftAmountRange()

std::optional< ConstantRange > GISelValueTracking::getValidShiftAmountRange	(	Register	R,
		const APInt &	DemandedElts,
		unsigned	Depth
	)

If a G_SHL/G_ASHR/G_LSHR node with shift operand R has shift amounts that are all less than the element bit-width of the shift node, return the valid constant range.

Definition at line 2064 of file GISelValueTracking.cpp.

References assert(), llvm::BitWidth, llvm::Depth, llvm::ConstantRange::fromKnownBits(), getKnownBits(), llvm::KnownBits::getMaxValue(), llvm::LLT::getScalarSizeInBits(), llvm::MachineRegisterInfo::getType(), llvm::MachineRegisterInfo::getVRegDef(), I, MI, llvm::APInt::uge(), llvm::APInt::ugt(), and llvm::APInt::ult().

Referenced by getValidMinimumShiftAmount().

◆ maskedValueIsZero()

bool llvm::GISelValueTracking::maskedValueIsZero	(	Register	Val,
		const APInt &	Mask
	)

inline

Returns: true if 'V & Mask' is known to be zero in DemandedElts. We use this predicate to simplify operations downstream. Mask is known to be zero for bits that V cannot have.

Definition at line 90 of file GISelValueTracking.h.

Referenced by llvm::AMDGPU::getBaseWithConstantOffset(), and signBitIsZero().

◆ signBitIsZero()

bool GISelValueTracking::signBitIsZero ( Register Op )

Returns: true if the sign bit of Op is known to be zero. We use this predicate to simplify operations downstream.

Definition at line 105 of file GISelValueTracking.cpp.

References llvm::BitWidth, llvm::LLT::getScalarSizeInBits(), llvm::APInt::getSignMask(), llvm::MachineRegisterInfo::getType(), and maskedValueIsZero().

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

include/llvm/CodeGen/GlobalISel/GISelValueTracking.h
lib/CodeGen/GlobalISel/GISelValueTracking.cpp

Public Member Functions

Static Public Member Functions

Protected Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ GISelValueTracking()

◆ ~GISelValueTracking()

Member Function Documentation

◆ changedInstr()

◆ changingInstr()

◆ computeKnownAlignment()

◆ computeKnownBitsForAlignment()

◆ computeKnownBitsImpl()

◆ computeKnownFPClass() [1/4]

◆ computeKnownFPClass() [2/4]

◆ computeKnownFPClass() [3/4]

◆ computeKnownFPClass() [4/4]

◆ computeNumSignBits() [1/2]

◆ computeNumSignBits() [2/2]

◆ createdInstr()

◆ erasingInstr()

◆ getDataLayout()

◆ getKnownBits() [1/3]

◆ getKnownBits() [2/3]

◆ getKnownBits() [3/3]

◆ getKnownOnes()

◆ getKnownZeroes()

◆ getMachineFunction()

◆ getMaxDepth()

◆ getValidMinimumShiftAmount()

◆ getValidShiftAmountRange()

◆ maskedValueIsZero()

◆ signBitIsZero()