This class models the accumulation of physical propagation delays on combinational paths along SSA dependences. More...

#include <Problems.h>

Inheritance diagram for circt::scheduling::ChainingProblem:

Collaboration diagram for circt::scheduling::ChainingProblem:

[legend]

Public Member Functions
std::optional< float >	getIncomingDelay (OperatorType opr)
	The incoming delay denotes the propagation time from the operand inputs to either the result outputs (combinational operators) or the first internal register stage. More...

void	setIncomingDelay (OperatorType opr, float delay)

std::optional< float >	getOutgoingDelay (OperatorType opr)
	The outgoing delay denotes the propagation time from either the operand inputs (combinational operators) or the last internal register stage to the result outputs. More...

void	setOutgoingDelay (OperatorType opr, float delay)

std::optional< float >	getStartTimeInCycle (Operation *op)
	Computed by the scheduler, this start time is relative to the beginning of the cycle that `op` starts in. More...

void	setStartTimeInCycle (Operation *op, float time)

virtual PropertyStringVector	getProperties (Operation *op) override

virtual PropertyStringVector	getProperties (OperatorType opr) override

virtual LogicalResult	check () override
	Return success if the constructed scheduling problem is valid. More...

virtual LogicalResult	verify () override
	Return success if the computed solution is valid. More...

Public Member Functions inherited from circt::scheduling::Problem
virtual	~Problem ()=default

void	insertOperation (Operation *op)
	Include `op` in this scheduling problem. More...

LogicalResult	insertDependence (Dependence dep)
	Include `dep` in the scheduling problem. More...

void	insertOperatorType (OperatorType opr)
	Include `opr` in this scheduling problem. More...

OperatorType	getOrInsertOperatorType (StringRef name)
	Retrieves the operator type identified by the client-specific `name`. More...

Operation *	getContainingOp ()
	Return the operation containing this problem, e.g. to emit diagnostics. More...

void	setContainingOp (Operation *op)
	Set the operation containing this problem, e.g. to emit diagnostics. More...

bool	hasOperation (Operation *op)
	Return true if `op` is part of this problem. More...

const OperationSet &	getOperations ()
	Return the set of operations. More...

DependenceRange	getDependences (Operation *op)
	Return a range object to transparently iterate over `op's` incoming 1) implicit def-use dependences (backed by the SSA graph), and then 2) explictly added auxiliary dependences. More...

bool	hasOperatorType (OperatorType opr)
	Return true if `opr` is part of this problem. More...

const OperatorTypeSet &	getOperatorTypes ()
	Return the set of operator types. More...

std::optional< OperatorType >	getLinkedOperatorType (Operation *op)
	The linked operator type provides the runtime characteristics for `op`. More...

void	setLinkedOperatorType (Operation *op, OperatorType opr)

std::optional< unsigned >	getLatency (OperatorType opr)
	The latency is the number of cycles `opr` needs to compute its result. More...

void	setLatency (OperatorType opr, unsigned val)

std::optional< unsigned >	getStartTime (Operation *op)
	Return the start time for `op`, as computed by the scheduler. More...

void	setStartTime (Operation *op, unsigned val)

std::optional< unsigned >	getEndTime (Operation *op)
	Returns the end time for `op`, as computed by the scheduler. More...

StringAttr	getInstanceName ()

void	setInstanceName (StringAttr name)

StringAttr	getLibraryName ()

void	setLibraryName (StringAttr name)

StringAttr	getOperationName (Operation *op)

void	setOperationName (Operation *op, StringAttr name)

virtual PropertyStringVector	getProperties (Dependence dep)

virtual PropertyStringVector	getProperties ()

Protected Member Functions
virtual LogicalResult	checkDelays (OperatorType opr)
	Incoming/outgoing delays are set for `opr` and non-negative. More...

virtual LogicalResult	verifyStartTimeInCycle (Operation *op)
	`op` has a non-negative start time in its cycle. More...

virtual LogicalResult	verifyPrecedenceInCycle (Dependence dep)
	If `dep` is an SSA edge and its source operation finishes in the same time step as the destination operation, the source's result is available before the destination starts in that cycle. More...

Protected Member Functions inherited from circt::scheduling::Problem
virtual LogicalResult	checkLinkedOperatorType (Operation *op)
	`op` is linked to a registered operator type. More...

virtual LogicalResult	checkLatency (OperatorType opr)
	`opr` has a latency. More...

virtual LogicalResult	verifyStartTime (Operation *op)
	`op` has a start time. More...

virtual LogicalResult	verifyPrecedence (Dependence dep)
	`dep's` source operation is available before `dep's` destination operation starts. More...

Private Attributes
OperatorTypeProperty< float >	incomingDelay

OperatorTypeProperty< float >	outgoingDelay

OperationProperty< float >	startTimeInCycle

Additional Inherited Members
Public Types inherited from circt::scheduling::Problem
using	Dependence = detail::Dependence
	A thin wrapper to allow a uniform handling of def-use and auxiliary dependences. More...

using	OperatorType = mlir::StringAttr
	Operator types are distinguished by name (chosen by the client). More...

using	OperationSet = llvm::SetVector< Operation * >

using	DependenceRange = llvm::iterator_range< detail::DependenceIterator >

using	OperatorTypeSet = llvm::SetVector< OperatorType >

using	PropertyStringVector = llvm::SmallVector< std::pair< std::string, std::string >, 2 >

Protected Types inherited from circt::scheduling::Problem
using	AuxDependenceMap = llvm::DenseMap< Operation , llvm::SmallSetVector< Operation , 4 > >

template<typename T >
using	OperationProperty = llvm::DenseMap< Operation *, std::optional< T > >

template<typename T >
using	DependenceProperty = llvm::DenseMap< Dependence, std::optional< T > >

template<typename T >
using	OperatorTypeProperty = llvm::DenseMap< OperatorType, std::optional< T > >

template<typename T >
using	InstanceProperty = std::optional< T >

Detailed Description

This class models the accumulation of physical propagation delays on combinational paths along SSA dependences.

Each operator type is annotated with estimated values for incoming and outgoing delays. Combinational operators (zero-latency, no internal registers) have only a single delay; this important special case is modeled by setting the incoming and outgoing delays to the same value.

A solution to this problem comprises per-operation start times in a continuous unit, e.g. in nanoseconds, inside the discrete time steps/cycles determined by the underlying scheduling problem.

Definition at line 340 of file Problems.h.

Member Function Documentation

◆ check()

LogicalResult ChainingProblem::check ( )

overridevirtual

Return success if the constructed scheduling problem is valid.

Reimplemented from circt::scheduling::Problem.

Definition at line 290 of file Problems.cpp.

References circt::scheduling::Problem::check().

◆ checkDelays()

LogicalResult ChainingProblem::checkDelays ( OperatorType opr )

protectedvirtual

Incoming/outgoing delays are set for opr and non-negative.

The delays are equal if opr is a zero-latency operator type.

Definition at line 224 of file Problems.cpp.

◆ getIncomingDelay()

std::optional<float> circt::scheduling::ChainingProblem::getIncomingDelay ( OperatorType opr )

inline

The incoming delay denotes the propagation time from the operand inputs to either the result outputs (combinational operators) or the first internal register stage.

Definition at line 351 of file Problems.h.

References incomingDelay.

◆ getOutgoingDelay()

std::optional<float> circt::scheduling::ChainingProblem::getOutgoingDelay ( OperatorType opr )

inline

The outgoing delay denotes the propagation time from either the operand inputs (combinational operators) or the last internal register stage to the result outputs.

Definition at line 361 of file Problems.h.

References outgoingDelay.

◆ getProperties() [1/2]

Problem::PropertyStringVector ChainingProblem::getProperties ( Operation * op )

overridevirtual

Reimplemented from circt::scheduling::Problem.

Definition at line 208 of file Problems.cpp.

References circt::scheduling::Problem::getProperties().

◆ getProperties() [2/2]

Problem::PropertyStringVector ChainingProblem::getProperties ( OperatorType opr )

overridevirtual

Reimplemented from circt::scheduling::Problem.

Definition at line 215 of file Problems.cpp.

References circt::scheduling::Problem::getProperties().

◆ getStartTimeInCycle()

std::optional<float> circt::scheduling::ChainingProblem::getStartTimeInCycle ( Operation * op )

inline

Computed by the scheduler, this start time is relative to the beginning of the cycle that op starts in.

Definition at line 370 of file Problems.h.

References startTimeInCycle.

◆ setIncomingDelay()

void circt::scheduling::ChainingProblem::setIncomingDelay	(	OperatorType	opr,
		float	delay
	)

inline

Definition at line 354 of file Problems.h.

References incomingDelay.

◆ setOutgoingDelay()

void circt::scheduling::ChainingProblem::setOutgoingDelay	(	OperatorType	opr,
		float	delay
	)

inline

Definition at line 364 of file Problems.h.

References outgoingDelay.

◆ setStartTimeInCycle()

void circt::scheduling::ChainingProblem::setStartTimeInCycle	(	Operation *	op,
		float	time
	)

inline

Definition at line 373 of file Problems.h.

References startTimeInCycle.

Referenced by circt::scheduling::computeStartTimesInCycle().

◆ verify()

LogicalResult ChainingProblem::verify ( )

overridevirtual

Return success if the computed solution is valid.

Reimplemented from circt::scheduling::Problem.

Definition at line 301 of file Problems.cpp.

References circt::scheduling::Problem::verify().

◆ verifyPrecedenceInCycle()

LogicalResult ChainingProblem::verifyPrecedenceInCycle ( Dependence dep )

protectedvirtual

If dep is an SSA edge and its source operation finishes in the same time step as the destination operation, the source's result is available before the destination starts in that cycle.

Definition at line 255 of file Problems.cpp.

References circt::scheduling::detail::Dependence::getDestination(), circt::scheduling::detail::Dependence::getSource(), and circt::scheduling::detail::Dependence::isAuxiliary().

◆ verifyStartTimeInCycle()

LogicalResult ChainingProblem::verifyStartTimeInCycle ( Operation * op )

protectedvirtual

op has a non-negative start time in its cycle.

Definition at line 248 of file Problems.cpp.

Member Data Documentation

◆ incomingDelay

OperatorTypeProperty<float> circt::scheduling::ChainingProblem::incomingDelay

private

Definition at line 344 of file Problems.h.

Referenced by getIncomingDelay(), and setIncomingDelay().

◆ outgoingDelay

OperatorTypeProperty<float> circt::scheduling::ChainingProblem::outgoingDelay

private

Definition at line 344 of file Problems.h.

Referenced by getOutgoingDelay(), and setOutgoingDelay().

◆ startTimeInCycle

OperationProperty<float> circt::scheduling::ChainingProblem::startTimeInCycle

private

Definition at line 345 of file Problems.h.

Referenced by getStartTimeInCycle(), and setStartTimeInCycle().

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

include/circt/Scheduling/Problems.h
lib/Scheduling/Problems.cpp

Public Member Functions

Protected Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

Member Function Documentation

◆ check()

◆ checkDelays()

◆ getIncomingDelay()

◆ getOutgoingDelay()

◆ getProperties() [1/2]

◆ getProperties() [2/2]

◆ getStartTimeInCycle()

◆ setIncomingDelay()

◆ setOutgoingDelay()

◆ setStartTimeInCycle()

◆ verify()

◆ verifyPrecedenceInCycle()

◆ verifyStartTimeInCycle()

Member Data Documentation

◆ incomingDelay

◆ outgoingDelay

◆ startTimeInCycle