#include "Target/Hexagon/HexagonHazardRecognizer.h"

Inheritance diagram for llvm::HexagonHazardRecognizer:

Public Member Functions
	HexagonHazardRecognizer (const InstrItineraryData II, const HexagonInstrInfo HII, const HexagonSubtarget &ST)

	~HexagonHazardRecognizer () override

void	Reset () override
	This callback is invoked when a new block of instructions is about to be scheduled.

HazardType	getHazardType (SUnit *SU, int stalls) override
	Return the hazard type of emitting this node.

void	EmitInstruction (SUnit *) override
	This callback is invoked when an instruction is emitted to be scheduled, to advance the hazard state.

bool	ShouldPreferAnother (SUnit *) override
	This callback may be invoked if getHazardType returns NoHazard.

void	AdvanceCycle () override
	This callback is invoked whenever the next top-down instruction to be scheduled cannot issue in the current cycle, either because of latency or resource conflicts.

Public Member Functions inherited from llvm::ScheduleHazardRecognizer
	ScheduleHazardRecognizer ()=default

virtual	~ScheduleHazardRecognizer ()

unsigned	getMaxLookAhead () const

bool	isEnabled () const

virtual bool	atIssueLimit () const
	atIssueLimit - Return true if no more instructions may be issued in this cycle.

virtual HazardType	getHazardType (SUnit *, int Stalls=0)
	getHazardType - Return the hazard type of emitting this node.

virtual void	Reset ()
	Reset - This callback is invoked when a new block of instructions is about to be schedule.

virtual void	EmitInstruction (SUnit *)
	EmitInstruction - This callback is invoked when an instruction is emitted, to advance the hazard state.

virtual void	EmitInstruction (MachineInstr *)
	This overload will be used when the hazard recognizer is being used by a non-scheduling pass, which does not use SUnits.

virtual unsigned	PreEmitNoops (SUnit *)
	PreEmitNoops - This callback is invoked prior to emitting an instruction.

virtual unsigned	PreEmitNoops (MachineInstr *)
	This overload will be used when the hazard recognizer is being used by a non-scheduling pass, which does not use SUnits.

virtual bool	ShouldPreferAnother (SUnit *)
	ShouldPreferAnother - This callback may be invoked if getHazardType returns NoHazard.

virtual void	AdvanceCycle ()
	AdvanceCycle - This callback is invoked whenever the next top-down instruction to be scheduled cannot issue in the current cycle, either because of latency or resource conflicts.

virtual void	RecedeCycle ()
	RecedeCycle - This callback is invoked whenever the next bottom-up instruction to be scheduled cannot issue in the current cycle, either because of latency or resource conflicts.

virtual void	EmitNoop ()
	EmitNoop - This callback is invoked when a noop was added to the instruction stream.

virtual void	EmitNoops (unsigned Quantity)
	EmitNoops - This callback is invoked when noops were added to the instruction stream.

Additional Inherited Members
Public Types inherited from llvm::ScheduleHazardRecognizer
enum	HazardType { NoHazard , Hazard , NoopHazard }

Protected Attributes inherited from llvm::ScheduleHazardRecognizer
unsigned	MaxLookAhead = 0
	MaxLookAhead - Indicate the number of cycles in the scoreboard state.

Detailed Description

Definition at line 22 of file HexagonHazardRecognizer.h.

Constructor & Destructor Documentation

◆ HexagonHazardRecognizer()

llvm::HexagonHazardRecognizer::HexagonHazardRecognizer	(	const InstrItineraryData *	II,
		const HexagonInstrInfo *	HII,
		const HexagonSubtarget &	ST
	)

inline

Definition at line 48 of file HexagonHazardRecognizer.h.

References TII.

◆ ~HexagonHazardRecognizer()

llvm::HexagonHazardRecognizer::~HexagonHazardRecognizer ( )

inlineoverride

Definition at line 53 of file HexagonHazardRecognizer.h.

Member Function Documentation

◆ AdvanceCycle()

void HexagonHazardRecognizer::AdvanceCycle ( )

overridevirtual

This callback is invoked whenever the next top-down instruction to be scheduled cannot issue in the current cycle, either because of latency or resource conflicts.

This should increment the internal state of the hazard recognizer so that previously "Hazard" instructions will now not be hazards.

Reimplemented from llvm::ScheduleHazardRecognizer.

Definition at line 72 of file HexagonHazardRecognizer.cpp.

References llvm::SmallSet< T, N, C >::clear(), llvm::DFAPacketizer::clearResources(), llvm::dbgs(), and LLVM_DEBUG.

◆ EmitInstruction()

void HexagonHazardRecognizer::EmitInstruction ( SUnit * SU )

overridevirtual

This callback is invoked when an instruction is emitted to be scheduled, to advance the hazard state.

Reimplemented from llvm::ScheduleHazardRecognizer.

Definition at line 112 of file HexagonHazardRecognizer.cpp.

References assert(), llvm::DFAPacketizer::canReserveResources(), llvm::MachineFunction::CreateMachineInstr(), llvm::dbgs(), llvm::MachineFunction::deleteMachineInstr(), llvm::HexagonInstrInfo::getDotNewOp(), llvm::SUnit::getInstr(), llvm::MachineOperand::getReg(), llvm::SmallSet< T, N, C >::insert(), llvm::MachineOperand::isDef(), llvm::HexagonInstrInfo::isHVXVec(), llvm::MachineOperand::isImplicit(), llvm::MachineOperand::isReg(), LLVM_DEBUG, llvm::HexagonInstrInfo::mayBeCurLoad(), llvm::HexagonInstrInfo::mayBeNewStore(), MI, llvm::DFAPacketizer::reserveResources(), and llvm::SUnit::Succs.

◆ getHazardType()

ScheduleHazardRecognizer::HazardType HexagonHazardRecognizer::getHazardType	(	SUnit *	SU,
		int	stalls
	)

overridevirtual

Return the hazard type of emitting this node.

There are three possible results. Either:

NoHazard: it is legal to issue this instruction on this cycle.
Hazard: issuing this instruction would stall the machine. If some other instruction is available, issue it first.

Reimplemented from llvm::ScheduleHazardRecognizer.

Definition at line 39 of file HexagonHazardRecognizer.cpp.

References llvm::DFAPacketizer::canReserveResources(), llvm::MachineFunction::CreateMachineInstr(), llvm::dbgs(), llvm::MachineFunction::deleteMachineInstr(), llvm::HexagonInstrInfo::getDotNewOp(), llvm::SUnit::getInstr(), llvm::ScheduleHazardRecognizer::Hazard, LLVM_DEBUG, MI, and llvm::ScheduleHazardRecognizer::NoHazard.

◆ Reset()

void HexagonHazardRecognizer::Reset ( )

overridevirtual

This callback is invoked when a new block of instructions is about to be scheduled.

The hazard state is set to an initialized state.

Reimplemented from llvm::ScheduleHazardRecognizer.

Definition at line 27 of file HexagonHazardRecognizer.cpp.

References llvm::SmallSet< T, N, C >::clear(), llvm::DFAPacketizer::clearResources(), llvm::dbgs(), and LLVM_DEBUG.

◆ ShouldPreferAnother()

bool HexagonHazardRecognizer::ShouldPreferAnother ( SUnit * SU )

overridevirtual

This callback may be invoked if getHazardType returns NoHazard.

Handle the cases when we prefer one instruction over another.

If, even though there is no hazard, it would be better to schedule another available instruction, this callback should return true.

Case 1 - we prefer not to generate multiple loads in the packet to avoid a potential bank conflict. Case 2 - if a packet contains a dot cur instruction, then we prefer the instruction that can use the dot cur result. However, if the use is not scheduled in the same packet, then prefer other instructions in the subsequent packet. Case 3 - we prefer a vector store that can be converted to a .new store. The packetizer will not generate the .new store if the store doesn't have resources to fit in the packet (but the .new store may have resources). We attempt to schedule the store as soon as possible to help packetize the two instructions together.

Reimplemented from llvm::ScheduleHazardRecognizer.

Definition at line 95 of file HexagonHazardRecognizer.cpp.

References llvm::SUnit::getInstr(), llvm::SUnit::isInstr(), and llvm::MachineInstr::mayLoad().

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

lib/Target/Hexagon/HexagonHazardRecognizer.h
lib/Target/Hexagon/HexagonHazardRecognizer.cpp

Public Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ HexagonHazardRecognizer()

◆ ~HexagonHazardRecognizer()

Member Function Documentation

◆ AdvanceCycle()

◆ EmitInstruction()

◆ getHazardType()

◆ Reset()

◆ ShouldPreferAnother()