RegisterPressure.cpp File Reference

#include "llvm/CodeGen/RegisterPressure.h"
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/CodeGen/LiveInterval.h"
#include "llvm/CodeGen/LiveIntervals.h"
#include "llvm/CodeGen/MachineBasicBlock.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/CodeGen/MachineInstrBundle.h"
#include "llvm/CodeGen/MachineOperand.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/RegisterClassInfo.h"
#include "llvm/CodeGen/SlotIndexes.h"
#include "llvm/CodeGen/TargetRegisterInfo.h"
#include "llvm/CodeGen/TargetSubtargetInfo.h"
#include "llvm/Config/llvm-config.h"
#include "llvm/MC/LaneBitmask.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
#include <algorithm>
#include <cassert>
#include <cstdint>
#include <cstdlib>
#include <cstring>
#include <iterator>
#include <limits>
#include <utility>
#include <vector>

Go to the source code of this file.

Functions
static void	increaseSetPressure (std::vector< unsigned > &CurrSetPressure, const MachineRegisterInfo &MRI, unsigned Reg, LaneBitmask PrevMask, LaneBitmask NewMask)
	Increase pressure for each pressure set provided by TargetRegisterInfo.
static void	decreaseSetPressure (std::vector< unsigned > &CurrSetPressure, const MachineRegisterInfo &MRI, Register Reg, LaneBitmask PrevMask, LaneBitmask NewMask)
	Decrease pressure for each pressure set provided by TargetRegisterInfo.
static const LiveRange *	getLiveRange (const LiveIntervals &LIS, unsigned Reg)
static LaneBitmask	getRegLanes (ArrayRef< VRegMaskOrUnit > RegUnits, Register RegUnit)
static void	addRegLanes (SmallVectorImpl< VRegMaskOrUnit > &RegUnits, VRegMaskOrUnit Pair)
static void	setRegZero (SmallVectorImpl< VRegMaskOrUnit > &RegUnits, Register RegUnit)
static void	removeRegLanes (SmallVectorImpl< VRegMaskOrUnit > &RegUnits, VRegMaskOrUnit Pair)
static LaneBitmask	getLanesWithProperty (const LiveIntervals &LIS, const MachineRegisterInfo &MRI, bool TrackLaneMasks, Register RegUnit, SlotIndex Pos, LaneBitmask SafeDefault, bool(*Property)(const LiveRange &LR, SlotIndex Pos))
static LaneBitmask	getLiveLanesAt (const LiveIntervals &LIS, const MachineRegisterInfo &MRI, bool TrackLaneMasks, Register RegUnit, SlotIndex Pos)
static void	computeExcessPressureDelta (ArrayRef< unsigned > OldPressureVec, ArrayRef< unsigned > NewPressureVec, RegPressureDelta &Delta, const RegisterClassInfo *RCI, ArrayRef< unsigned > LiveThruPressureVec)
	Find the max change in excess pressure across all sets.
static void	computeMaxPressureDelta (ArrayRef< unsigned > OldMaxPressureVec, ArrayRef< unsigned > NewMaxPressureVec, ArrayRef< PressureChange > CriticalPSets, ArrayRef< unsigned > MaxPressureLimit, RegPressureDelta &Delta)
	Find the max change in max pressure that either surpasses a critical PSet limit or exceeds the current MaxPressureLimit.
static LaneBitmask	findUseBetween (unsigned Reg, LaneBitmask LastUseMask, SlotIndex PriorUseIdx, SlotIndex NextUseIdx, const MachineRegisterInfo &MRI, const LiveIntervals *LIS)
	Helper to find a vreg use between two indices [PriorUseIdx, NextUseIdx).

Function Documentation

addRegLanes()

void addRegLanes ( SmallVectorImpl< VRegMaskOrUnit > & RegUnits, VRegMaskOrUnit Pair )

static

Definition at line 376 of file RegisterPressure.cpp.

References llvm::LaneBitmask::any(), assert(), llvm::SmallVectorTemplateCommon< T, typename >::end(), llvm::find_if(), I, llvm::VRegMaskOrUnit::LaneMask, llvm::Other, llvm::SmallVectorTemplateBase< T, bool >::push_back(), and llvm::VRegMaskOrUnit::RegUnit.

Referenced by llvm::RegPressureTracker::recede().

computeExcessPressureDelta()

void computeExcessPressureDelta ( ArrayRef< unsigned > OldPressureVec, ArrayRef< unsigned > NewPressureVec, RegPressureDelta & Delta, const RegisterClassInfo * RCI, ArrayRef< unsigned > LiveThruPressureVec )

static

Find the max change in excess pressure across all sets.

Definition at line 945 of file RegisterPressure.cpp.

References llvm::ArrayRef< T >::empty(), llvm::RegPressureDelta::Excess, llvm::RegisterClassInfo::getRegPressureSetLimit(), llvm::PressureChange::setUnitInc(), and llvm::ArrayRef< T >::size().

Referenced by llvm::RegPressureTracker::getMaxDownwardPressureDelta(), and llvm::RegPressureTracker::getMaxUpwardPressureDelta().

computeMaxPressureDelta()

void computeMaxPressureDelta ( ArrayRef< unsigned > OldMaxPressureVec, ArrayRef< unsigned > NewMaxPressureVec, ArrayRef< PressureChange > CriticalPSets, ArrayRef< unsigned > MaxPressureLimit, RegPressureDelta & Delta )

static

Find the max change in max pressure that either surpasses a critical PSet limit or exceeds the current MaxPressureLimit.

FIXME: comparing each element of the old and new MaxPressure vectors here is silly. It's done now to demonstrate the concept but will go away with a RegPressureTracker API change to work with pressure differences.

Definition at line 984 of file RegisterPressure.cpp.

References llvm::RegPressureDelta::CriticalMax, llvm::RegPressureDelta::CurrentMax, llvm::PressureChange::isValid(), llvm::PressureChange::setUnitInc(), and llvm::ArrayRef< T >::size().

Referenced by llvm::RegPressureTracker::getMaxDownwardPressureDelta(), and llvm::RegPressureTracker::getMaxUpwardPressureDelta().

decreaseSetPressure()

void decreaseSetPressure ( std::vector< unsigned > & CurrSetPressure, const MachineRegisterInfo & MRI, Register Reg, LaneBitmask PrevMask, LaneBitmask NewMask )

static

Decrease pressure for each pressure set provided by TargetRegisterInfo.

Definition at line 63 of file RegisterPressure.cpp.

References llvm::LaneBitmask::any(), assert(), llvm::PSetIterator::getWeight(), llvm::PSetIterator::isValid(), MRI, llvm::LaneBitmask::none(), none, and Reg.

Referenced by llvm::RegPressureTracker::decreaseRegPressure().

findUseBetween()

LaneBitmask findUseBetween ( unsigned Reg, LaneBitmask LastUseMask, SlotIndex PriorUseIdx, SlotIndex NextUseIdx, const MachineRegisterInfo & MRI, const LiveIntervals * LIS )

static

Helper to find a vreg use between two indices [PriorUseIdx, NextUseIdx).

The query starts with a lane bitmask which gets lanes/bits removed for every use we find.

Definition at line 1212 of file RegisterPressure.cpp.

References llvm::LiveIntervals::getInstructionIndex(), llvm::LaneBitmask::getNone(), llvm::MachineOperand::getParent(), llvm::SlotIndex::getRegSlot(), llvm::MachineOperand::getSubReg(), llvm::MachineOperand::isUndef(), MI, MRI, llvm::LaneBitmask::none(), Reg, and TRI.

Referenced by llvm::GCNDownwardRPTracker::bumpDownwardPressure(), and llvm::RegPressureTracker::bumpDownwardPressure().

getLanesWithProperty()

LaneBitmask getLanesWithProperty ( const LiveIntervals & LIS, const MachineRegisterInfo & MRI, bool TrackLaneMasks, Register RegUnit, SlotIndex Pos, LaneBitmask SafeDefault, bool(* Property )(const LiveRange &LR, SlotIndex Pos) )

static

Definition at line 417 of file RegisterPressure.cpp.

References llvm::LaneBitmask::getAll(), llvm::LiveIntervals::getCachedRegUnit(), llvm::LiveIntervals::getInterval(), llvm::LaneBitmask::getNone(), llvm::LiveInterval::hasSubRanges(), llvm::Register::isVirtual(), MRI, and llvm::LiveInterval::subranges().

Referenced by llvm::GCNRPTracker::getLastUsedLanes(), llvm::RegPressureTracker::getLastUsedLanes(), getLiveLanesAt(), llvm::RegPressureTracker::getLiveLanesAt(), and llvm::RegPressureTracker::getLiveThroughAt().

getLiveLanesAt()

LaneBitmask getLiveLanesAt ( const LiveIntervals & LIS, const MachineRegisterInfo & MRI, bool TrackLaneMasks, Register RegUnit, SlotIndex Pos )

static

Definition at line 445 of file RegisterPressure.cpp.

References llvm::LaneBitmask::getAll(), getLanesWithProperty(), llvm::LiveRange::liveAt(), and MRI.

Referenced by llvm::RegisterOperands::adjustLaneLiveness().

getLiveRange()

const LiveRange * getLiveRange ( const LiveIntervals & LIS, unsigned Reg )

static

Definition at line 233 of file RegisterPressure.cpp.

References llvm::LiveIntervals::getCachedRegUnit(), llvm::LiveIntervals::getInterval(), llvm::Register::isVirtualRegister(), and Reg.

Referenced by llvm::RegisterOperands::detectDeadDefs().

getRegLanes()

LaneBitmask getRegLanes ( ArrayRef< VRegMaskOrUnit > RegUnits, Register RegUnit )

static

Definition at line 366 of file RegisterPressure.cpp.

References llvm::ArrayRef< T >::end(), llvm::find_if(), llvm::LaneBitmask::getNone(), I, and llvm::Other.

Referenced by llvm::RegPressureTracker::bumpUpwardPressure().

increaseSetPressure()

void increaseSetPressure ( std::vector< unsigned > & CurrSetPressure, const MachineRegisterInfo & MRI, unsigned Reg, LaneBitmask PrevMask, LaneBitmask NewMask )

static

Increase pressure for each pressure set provided by TargetRegisterInfo.

Definition at line 49 of file RegisterPressure.cpp.

References llvm::LaneBitmask::any(), assert(), llvm::PSetIterator::getWeight(), llvm::PSetIterator::isValid(), MRI, llvm::LaneBitmask::none(), none, and Reg.

Referenced by llvm::RegPressureTracker::discoverLiveInOrOut(), llvm::RegPressureTracker::initLiveThru(), and llvm::RegPressureTracker::recede().

removeRegLanes()

void removeRegLanes ( SmallVectorImpl< VRegMaskOrUnit > & RegUnits, VRegMaskOrUnit Pair )

static

Definition at line 402 of file RegisterPressure.cpp.

References llvm::LaneBitmask::any(), assert(), llvm::SmallVectorTemplateCommon< T, typename >::end(), llvm::SmallVectorImpl< T >::erase(), llvm::find_if(), I, llvm::VRegMaskOrUnit::LaneMask, llvm::Other, and llvm::VRegMaskOrUnit::RegUnit.

Referenced by llvm::RegPressureTracker::recede().

setRegZero()

void setRegZero ( SmallVectorImpl< VRegMaskOrUnit > & RegUnits, Register RegUnit )

static

Definition at line 390 of file RegisterPressure.cpp.

References llvm::SmallVectorImpl< T >::emplace_back(), llvm::SmallVectorTemplateCommon< T, typename >::end(), llvm::find_if(), llvm::LaneBitmask::getNone(), I, and llvm::Other.

Referenced by llvm::RegPressureTracker::recede().