Calculate auxiliary information for a virtual register such as its spill weight and allocation hint. More...

#include "llvm/CodeGen/CalcSpillWeights.h"

Public Types
using	NormalizingFn = float(*)(float, unsigned, unsigned)

Public Member Functions
	VirtRegAuxInfo (MachineFunction &mf, LiveIntervals &lis, VirtRegMap *vrm, const MachineLoopInfo &loops, const MachineBlockFrequencyInfo &mbfi, NormalizingFn norm=normalizeSpillWeight)

void	calculateSpillWeightAndHint (LiveInterval &li)
	(re)compute li's spill weight and allocation hint. More...

float	futureWeight (LiveInterval &li, SlotIndex start, SlotIndex end)
	Compute future expected spill weight of a split artifact of li that will span between start and end slot indexes. More...

float	weightCalcHelper (LiveInterval &li, SlotIndex start=nullptr, SlotIndex end=nullptr)
	Helper function for weight calculations. More...

Detailed Description

Calculate auxiliary information for a virtual register such as its spill weight and allocation hint.

Definition at line 47 of file CalcSpillWeights.h.

Member Typedef Documentation

◆ NormalizingFn

using llvm::VirtRegAuxInfo::NormalizingFn = float (*)(float, unsigned, unsigned)

Definition at line 49 of file CalcSpillWeights.h.

Constructor & Destructor Documentation

◆ VirtRegAuxInfo()

llvm::VirtRegAuxInfo::VirtRegAuxInfo	(	MachineFunction &	mf,
		LiveIntervals &	lis,
		VirtRegMap *	vrm,
		const MachineLoopInfo &	loops,
		const MachineBlockFrequencyInfo &	mbfi,
		NormalizingFn	norm = `normalizeSpillWeight`
	)

inline

Definition at line 61 of file CalcSpillWeights.h.

References calculateSpillWeightAndHint(), llvm::calculateSpillWeightsAndHints(), llvm::sys::path::end(), futureWeight(), llvm::normalizeSpillWeight(), and weightCalcHelper().

Member Function Documentation

◆ calculateSpillWeightAndHint()

void VirtRegAuxInfo::calculateSpillWeightAndHint ( LiveInterval & li )

(re)compute li's spill weight and allocation hint.

Definition at line 138 of file CalcSpillWeights.cpp.

References llvm::LiveInterval::weight, and weightCalcHelper().

Referenced by llvm::LiveRangeEdit::calculateRegClassAndHint(), llvm::calculateSpillWeightsAndHints(), and VirtRegAuxInfo().

◆ futureWeight()

float VirtRegAuxInfo::futureWeight	(	LiveInterval &	li,
		SlotIndex	start,
		SlotIndex	end
	)

Compute future expected spill weight of a split artifact of li that will span between start and end slot indexes.

Parameters

li	The live interval to be split.
start	The expected begining of the split artifact. Instructions before start will not affect the weight.
end	The expected end of the split artifact. Instructions after end will not affect the weight.

Returns: The expected spill weight of the split artifact. Returns negative weight for unspillable li.

Definition at line 146 of file CalcSpillWeights.cpp.

References weightCalcHelper().

Referenced by VirtRegAuxInfo().

◆ weightCalcHelper()

float VirtRegAuxInfo::weightCalcHelper	(	LiveInterval &	li,
		SlotIndex *	start = `nullptr`,
		SlotIndex *	end = `nullptr`
	)

Helper function for weight calculations.

(Re)compute li's spill weight and allocation hint, or, for non null start and end - compute future expected spill weight of a split artifact of li that will span between start and end slot indexes.

Parameters

li	The live interval for which to compute the weight.
start	The expected begining of the split artifact. Instructions before start will not affect the weight. Relevant for weight calculation of future split artifact.
end	The expected end of the split artifact. Instructions after end will not affect the weight. Relevant for weight calculation of future split artifact.

Returns: The spill weight. Returns negative weight for unspillable li.

Definition at line 151 of file CalcSpillWeights.cpp.

References llvm::MachineRegisterInfo::addRegAllocationHint(), assert(), llvm::MachineRegisterInfo::clearSimpleHint(), copyHint(), llvm::SlotIndex::distance(), E, llvm::sys::path::end(), llvm::LiveIntervals::getMBBFromIndex(), llvm::MachineInstr::getParent(), llvm::MachineRegisterInfo::getRegAllocationHint(), llvm::MachineFunction::getRegInfo(), llvm::TargetSubtargetInfo::getRegisterInfo(), llvm::LiveInterval::getSize(), llvm::LiveIntervals::getSpillWeight(), llvm::MachineFunction::getSubtarget(), I, llvm::SmallPtrSetImpl< PtrType >::insert(), llvm::MachineRegisterInfo::isAllocatable(), llvm::MachineInstr::isCopy(), llvm::MachineInstr::isDebugInstr(), llvm::MachineInstr::isIdentityCopy(), llvm::MachineInstr::isImplicitDef(), llvm::LiveRange::isLiveAtIndexes(), llvm::LoopBase< BlockT, LoopT >::isLoopExiting(), llvm::TargetRegisterInfo::isPhysicalRegister(), isRematerializable(), llvm::LiveInterval::isSpillable(), llvm::TargetRegisterInfo::isVirtualRegister(), llvm::LiveRange::isZeroLength(), Loops, llvm::LiveInterval::markNotSpillable(), llvm::operator<(), P, llvm::MachineInstr::readsWritesVirtualRegister(), llvm::LiveInterval::reg, Reg, llvm::MachineRegisterInfo::reg_instr_begin(), llvm::MachineRegisterInfo::reg_instr_end(), and llvm::RISCVFenceField::W.

Referenced by calculateSpillWeightAndHint(), futureWeight(), and VirtRegAuxInfo().

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

include/llvm/CodeGen/CalcSpillWeights.h
lib/CodeGen/CalcSpillWeights.cpp

Public Types

Public Member Functions