Classes
struct	Object
struct	DebugPoint
struct	OpenPath
class	DataflowPath
struct	LongestPathAnalysisOptions
	Configuration options for the longest path analysis. More...
class	LongestPathAnalysis
class	IncrementalLongestPathAnalysis
class	LongestPathCollection
class	ResourceUsageAnalysis
	Analysis that computes resource usage for Synth dialect operations. More...
class	ValueWithArrivalTime
	Helper class for delay-aware tree building. More...
struct	Signal
	Edge representation in the logic network. More...
struct	LogicNetworkGate
	Represents a single gate/node in the flat logic network. More...
class	LogicNetwork
	Flat logic network representation for efficient cut enumeration. More...
struct	MatchResult
	Result of matching a cut against a pattern. More...
class	MatchedPattern
	Represents a cut that has been successfully matched to a rewriting pattern. More...
class	Cut
	Represents a cut in the combinational logic network. More...
class	CutSet
	Manages a collection of cuts for a single logic node using priority cuts algorithm. More...
struct	CutRewriterOptions
	Configuration options for the cut-based rewriting algorithm. More...
struct	CutEnumeratorStats
class	TrackedSpecificBumpPtrAllocator
class	CutEnumerator
	Cut enumeration engine for combinational logic networks. More...
struct	CutRewritePattern
	Base class for cut rewriting patterns used in combinational logic optimization. More...
class	CutRewritePatternSet
	Manages a collection of rewriting patterns for combinational logic optimization. More...
class	CutRewriter
	Main cut-based rewriting algorithm for combinational logic optimization. More...
struct	CombLoweringPipelineOptions
	Options for the aig lowering pipeline. More...
struct	SynthOptimizationPipelineOptions
	Options for the synth optimization pipeline. More...

Typedefs
using	DelayType = int64_t

Enumerations
enum	OptimizationStrategy { OptimizationStrategyArea , OptimizationStrategyTiming }
	Optimization strategy. More...

Functions
llvm::json::Value	toJSON (const circt::synth::DataflowPath &path)
void	registerSynthAnalysisPrerequisitePasses ()
void	populateVariadicAndInverterLoweringPatterns (mlir::RewritePatternSet &patterns)
void	populateVariadicXorInverterLoweringPatterns (mlir::RewritePatternSet &patterns)
bool	isLogicNetworkOp (mlir::Operation *op)
LogicalResult	topologicallySortGraphRegionBlocks (mlir::Operation op, llvm::function_ref< bool(mlir::Value, mlir::Operation )> isOperandReady)
	This function performs a topological sort on the operations within each block of graph regions in the given operation.
template<typename T>
T	buildBalancedTreeWithArrivalTimes (llvm::ArrayRef< T > elements, llvm::function_ref< T(T, T)> combine)
	Build a balanced binary tree using a priority queue to greedily pair elements with earliest arrival times.
template<typename T>
T	evaluateDotLogic (const T &x, const T &y, const T &z)
	Evaluate the Boolean function x ^ (z \| (x & y)).
template<typename T>
T	evaluateMajorityLogic (const T &a, const T &b, const T &c)
llvm::APInt	invertBooleanLogic (llvm::APInt value)
llvm::KnownBits	invertBooleanLogic (llvm::KnownBits value)
llvm::KnownBits	applyInputInversion (llvm::KnownBits value, bool inverted)
template<typename T>
T	evaluateOneHotLogic (const T &a, const T &b, const T &c)
template<typename T>
T	evaluateMuxLogic (const T &a, const T &b, const T &c)
template<typename T>
T	evaluateGambleLogic (const T &a, const T &b, const T &c)
LogicalResult	topologicallySortLogicNetwork (mlir::Operation *op)
FailureOr< BinaryTruthTable >	getTruthTable (ValueRange values, Block *block)
	Get the truth table for operations within a block.
void	buildCombLoweringPipeline (mlir::OpPassManager &pm, const CombLoweringPipelineOptions &options)
	Populate the synthesis pipelines.
void	buildSynthOptimizationPipeline (mlir::OpPassManager &pm, const SynthOptimizationPipelineOptions &options)
void	registerSynthesisPipeline ()
	Register the synthesis pipelines.

Variables
static constexpr unsigned	maxTruthTableInputs = 16
	Maximum number of inputs supported for truth table generation.

Typedef Documentation

◆ DelayType

using circt::synth::DelayType = int64_t

Definition at line 40 of file CutRewriter.h.

Enumeration Type Documentation

◆ OptimizationStrategy

enum circt::synth::OptimizationStrategy

Optimization strategy.

Enumerator
OptimizationStrategyArea	Optimize for minimal area.
OptimizationStrategyTiming	Optimize for minimal critical path delay.

Definition at line 24 of file SynthPasses.h.

Function Documentation

◆ applyInputInversion()

llvm::KnownBits circt::synth::applyInputInversion	(	llvm::KnownBits	value,
		bool	inverted )

inline

Definition at line 154 of file SynthOps.h.

◆ buildBalancedTreeWithArrivalTimes()

template<typename T>

T circt::synth::buildBalancedTreeWithArrivalTimes	(	llvm::ArrayRef< T >	elements,
		llvm::function_ref< T(T, T)>	combine )

Build a balanced binary tree using a priority queue to greedily pair elements with earliest arrival times.

This minimizes the critical path delay.

Template parameters: T - The element type (must have operator> defined)

The algorithm uses a min-heap to repeatedly combine the two elements with the earliest arrival times, which is optimal for minimizing maximum delay.

Definition at line 105 of file SynthOps.h.

References assert().

◆ buildCombLoweringPipeline()

void circt::synth::buildCombLoweringPipeline	(	mlir::OpPassManager &	pm,
		const CombLoweringPipelineOptions &	options )

Populate the synthesis pipelines.

Referenced by registerSynthesisPipeline().

◆ buildSynthOptimizationPipeline()

void circt::synth::buildSynthOptimizationPipeline	(	mlir::OpPassManager &	pm,
		const SynthOptimizationPipelineOptions &	options )

Referenced by registerSynthesisPipeline().

◆ evaluateDotLogic()

template<typename T>

T circt::synth::evaluateDotLogic	(	const T &	x,
		const T &	y,
		const T &	z )

Evaluate the Boolean function x ^ (z | (x & y)).

Definition at line 135 of file SynthOps.h.

Referenced by applyGateSemantics().

◆ evaluateGambleLogic()

template<typename T>

T circt::synth::evaluateGambleLogic	(	const T &	a,
		const T &	b,
		const T &	c )

Definition at line 173 of file SynthOps.h.

References invertBooleanLogic().

Referenced by applyGateSemantics().

◆ evaluateMajorityLogic()

template<typename T>

T circt::synth::evaluateMajorityLogic	(	const T &	a,
		const T &	b,
		const T &	c )

Definition at line 140 of file SynthOps.h.

Referenced by applyGateSemantics().

◆ evaluateMuxLogic()

template<typename T>

T circt::synth::evaluateMuxLogic	(	const T &	a,
		const T &	b,
		const T &	c )

Definition at line 168 of file SynthOps.h.

References invertBooleanLogic().

Referenced by applyGateSemantics().

◆ evaluateOneHotLogic()

template<typename T>

T circt::synth::evaluateOneHotLogic	(	const T &	a,
		const T &	b,
		const T &	c )

Definition at line 162 of file SynthOps.h.

References invertBooleanLogic().

Referenced by applyGateSemantics().

◆ getTruthTable()

FailureOr< BinaryTruthTable > circt::synth::getTruthTable	(	ValueRange	values,
		Block *	block )

Get the truth table for operations within a block.

Definition at line 308 of file CutRewriter.cpp.

References circt::createVarMask(), circt::hw::getBitWidth(), and maxTruthTableInputs.

Referenced by getNPNClassFromModule().

◆ invertBooleanLogic() [1/2]

llvm::APInt circt::synth::invertBooleanLogic ( llvm::APInt value )

inline

Definition at line 144 of file SynthOps.h.

Referenced by evaluateGambleLogic(), evaluateMuxLogic(), and evaluateOneHotLogic().

◆ invertBooleanLogic() [2/2]

llvm::KnownBits circt::synth::invertBooleanLogic ( llvm::KnownBits value )

inline

Definition at line 149 of file SynthOps.h.

◆ isLogicNetworkOp()

bool circt::synth::isLogicNetworkOp ( mlir::Operation * op )

◆ populateVariadicAndInverterLoweringPatterns()

void circt::synth::populateVariadicAndInverterLoweringPatterns ( mlir::RewritePatternSet & patterns )

Referenced by populateCombToAIGConversionPatterns().

◆ populateVariadicXorInverterLoweringPatterns()

void circt::synth::populateVariadicXorInverterLoweringPatterns ( mlir::RewritePatternSet & patterns )

Referenced by populateCombToAIGConversionPatterns().

◆ registerSynthAnalysisPrerequisitePasses()

void circt::synth::registerSynthAnalysisPrerequisitePasses ( )

inline

Definition at line 361 of file LongestPathAnalysis.h.

◆ registerSynthesisPipeline()

void circt::synth::registerSynthesisPipeline ( void )

Register the synthesis pipelines.

Definition at line 155 of file SynthesisPipeline.cpp.

References buildCombLoweringPipeline(), and buildSynthOptimizationPipeline().

Referenced by registerSynthesisPipeline().

◆ toJSON()

llvm::json::Value circt::synth::toJSON ( const circt::synth::DataflowPath & path )

Definition at line 433 of file LongestPathAnalysis.cpp.

References toJSON().

Referenced by toJSON(), toJSON(), toJSON(), toJSON(), and toJSON().

◆ topologicallySortGraphRegionBlocks()

LogicalResult circt::synth::topologicallySortGraphRegionBlocks	(	mlir::Operation *	op,
		llvm::function_ref< bool(mlir::Value, mlir::Operation *)>	isOperandReady )

This function performs a topological sort on the operations within each block of graph regions in the given operation.

It uses MLIR's topological sort utility as a wrapper, ensuring that operations are ordered such that all operands are defined before their uses. The isOperandReady callback allows customization of when an operand is considered ready for sorting.

Definition at line 543 of file SynthOps.cpp.

References success().

◆ topologicallySortLogicNetwork()

LogicalResult circt::synth::topologicallySortLogicNetwork ( mlir::Operation * op )

Referenced by circt::synth::CutEnumerator::enumerateCuts(), and circt::synth::CutRewriter::run().

Variable Documentation

◆ maxTruthTableInputs

unsigned circt::synth::maxTruthTableInputs = 16

staticconstexpr

Maximum number of inputs supported for truth table generation.

This limit prevents excessive memory usage as truth table size grows exponentially with the number of inputs (2^n entries).

Definition at line 45 of file CutRewriter.h.

Referenced by getNPNClassFromModule(), and getTruthTable().

Classes

Typedefs

Enumerations

Functions

Variables

Typedef Documentation

◆ DelayType

Enumeration Type Documentation

◆ OptimizationStrategy

Function Documentation

◆ applyInputInversion()

◆ buildBalancedTreeWithArrivalTimes()

◆ buildCombLoweringPipeline()

◆ buildSynthOptimizationPipeline()

◆ evaluateDotLogic()

◆ evaluateGambleLogic()

◆ evaluateMajorityLogic()

◆ evaluateMuxLogic()

◆ evaluateOneHotLogic()

◆ getTruthTable()

◆ invertBooleanLogic() [1/2]

◆ invertBooleanLogic() [2/2]

◆ isLogicNetworkOp()

◆ populateVariadicAndInverterLoweringPatterns()

◆ populateVariadicXorInverterLoweringPatterns()

◆ registerSynthAnalysisPrerequisitePasses()

◆ registerSynthesisPipeline()

◆ toJSON()

◆ topologicallySortGraphRegionBlocks()

◆ topologicallySortLogicNetwork()

Variable Documentation

◆ maxTruthTableInputs