Analysis that identifies uniform values in a data-parallel execution. More...

#include "llvm/ADT/GenericUniformityImpl.h"

Public Types
using	BlockT = typename ContextT::BlockT
using	FunctionT = typename ContextT::FunctionT
using	ValueRefT = typename ContextT::ValueRefT
using	ConstValueRefT = typename ContextT::ConstValueRefT
using	UseT = typename ContextT::UseT
using	InstructionT = typename ContextT::InstructionT
using	DominatorTreeT = typename ContextT::DominatorTreeT
using	CycleInfoT = GenericCycleInfo<ContextT>
using	CycleT = typename CycleInfoT::CycleT
using	SyncDependenceAnalysisT = GenericSyncDependenceAnalysis<ContextT>
using	DivergenceDescriptorT
using	BlockLabelMapT = typename SyncDependenceAnalysisT::BlockLabelMap
using	TemporalDivergenceTuple

Public Member Functions
	GenericUniformityAnalysisImpl (const DominatorTreeT &DT, const CycleInfoT &CI, const TargetTransformInfo *TTI)
void	initialize ()
const FunctionT &	getFunction () const
void	addUniformOverride (const InstructionT &Instr)
	Mark `UniVal` as a value that is always uniform.
void	markDivergent (const InstructionT &I)
	Examine `I` for divergent outputs and add to the worklist.
bool	markDivergent (ConstValueRefT DivVal)
	Mark `DivVal` as a divergent value by removing it from UniformValues.
bool	markDefsDivergent (const InstructionT &Instr)
	Mark outputs of `Instr` as divergent.
void	compute ()
	Propagate divergence to all instructions in the region.
bool	isAlwaysUniform (const InstructionT &Instr) const
	Whether `Val` will always return a uniform value regardless of its operands.
bool	hasDivergentDefs (const InstructionT &I) const
bool	isDivergent (const InstructionT &I) const
bool	isDivergent (ConstValueRefT V) const
	Whether `Val` is divergent at its definition.
bool	isDivergentUse (const UseT &U) const
bool	hasDivergentTerminator (const BlockT &B) const
void	print (raw_ostream &out) const
bool	printDivergentArgs (raw_ostream &out) const
	Print divergent arguments and return true if any were found.
void	recordTemporalDivergence (ConstValueRefT, const InstructionT , const CycleT )
bool	isCustomUniform (const InstructionT &I) const
	Check if an instruction with Custom uniformity can be proven uniform based on its operands.
void	addCustomUniformityCandidate (const InstructionT *I)
	Add an instruction that requires custom uniformity analysis.
bool	hasDivergentDefs (const Instruction &I) const
bool	markDefsDivergent (const Instruction &Instr)
bool	printDivergentArgs (raw_ostream &OS) const
void	initialize ()
bool	isDivergentUse (const Use &U) const
bool	hasDivergentDefs (const MachineInstr &I) const
bool	markDefsDivergent (const MachineInstr &Instr)
void	initialize ()
bool	isDivergentUse (const MachineOperand &U) const

Public Attributes
SmallVector< TemporalDivergenceTuple, 8 >	TemporalDivergenceList

Protected Member Functions
void	analyzeControlDivergence (const InstructionT &Term)
	Mark `Term` as divergent and push all Instructions that become divergent as a result on the worklist.

Protected Attributes
const ContextT &	Context
const FunctionT &	F
const CycleInfoT &	CI
const TargetTransformInfo *	TTI = nullptr
bool	HasBranchDivergence = false
SmallPtrSet< const BlockT *, 32 >	DivergentTermBlocks
DenseSet< ConstValueRefT >	UniformValues
std::vector< const InstructionT * >	Worklist
SmallPtrSet< const InstructionT *, 8 >	CustomUniformityCandidates

Detailed Description

template<typename ContextT>
class llvm::GenericUniformityAnalysisImpl< ContextT >

Analysis that identifies uniform values in a data-parallel execution.

This analysis propagates divergence in a data-parallel context from sources of divergence to all users. It can be instantiated for an IR that provides a suitable SSAContext.

Definition at line 330 of file GenericUniformityImpl.h.

Member Typedef Documentation

◆ BlockLabelMapT

template<typename ContextT>

using llvm::GenericUniformityAnalysisImpl< ContextT >::BlockLabelMapT = typename SyncDependenceAnalysisT::BlockLabelMap

Definition at line 346 of file GenericUniformityImpl.h.

◆ BlockT

template<typename ContextT>

using llvm::GenericUniformityAnalysisImpl< ContextT >::BlockT = typename ContextT::BlockT

Definition at line 332 of file GenericUniformityImpl.h.

◆ ConstValueRefT

template<typename ContextT>

using llvm::GenericUniformityAnalysisImpl< ContextT >::ConstValueRefT = typename ContextT::ConstValueRefT

Definition at line 335 of file GenericUniformityImpl.h.

◆ CycleInfoT

template<typename ContextT>

using llvm::GenericUniformityAnalysisImpl< ContextT >::CycleInfoT = GenericCycleInfo<ContextT>

Definition at line 340 of file GenericUniformityImpl.h.

◆ CycleT

template<typename ContextT>

using llvm::GenericUniformityAnalysisImpl< ContextT >::CycleT = typename CycleInfoT::CycleT

Definition at line 341 of file GenericUniformityImpl.h.

◆ DivergenceDescriptorT

template<typename ContextT>

using llvm::GenericUniformityAnalysisImpl< ContextT >::DivergenceDescriptorT

Initial value:

typename SyncDependenceAnalysisT::DivergenceDescriptor

Definition at line 344 of file GenericUniformityImpl.h.

◆ DominatorTreeT

template<typename ContextT>

using llvm::GenericUniformityAnalysisImpl< ContextT >::DominatorTreeT = typename ContextT::DominatorTreeT

Definition at line 338 of file GenericUniformityImpl.h.

◆ FunctionT

template<typename ContextT>

using llvm::GenericUniformityAnalysisImpl< ContextT >::FunctionT = typename ContextT::FunctionT

Definition at line 333 of file GenericUniformityImpl.h.

◆ InstructionT

template<typename ContextT>

using llvm::GenericUniformityAnalysisImpl< ContextT >::InstructionT = typename ContextT::InstructionT

Definition at line 337 of file GenericUniformityImpl.h.

◆ SyncDependenceAnalysisT

template<typename ContextT>

using llvm::GenericUniformityAnalysisImpl< ContextT >::SyncDependenceAnalysisT = GenericSyncDependenceAnalysis<ContextT>

Definition at line 343 of file GenericUniformityImpl.h.

◆ TemporalDivergenceTuple

template<typename ContextT>

using llvm::GenericUniformityAnalysisImpl< ContextT >::TemporalDivergenceTuple

Initial value:

std::tuple<ConstValueRefT, InstructionT *, const CycleT *>

Definition at line 348 of file GenericUniformityImpl.h.

◆ UseT

template<typename ContextT>

using llvm::GenericUniformityAnalysisImpl< ContextT >::UseT = typename ContextT::UseT

Definition at line 336 of file GenericUniformityImpl.h.

◆ ValueRefT

template<typename ContextT>

using llvm::GenericUniformityAnalysisImpl< ContextT >::ValueRefT = typename ContextT::ValueRefT

Definition at line 334 of file GenericUniformityImpl.h.

Constructor & Destructor Documentation

◆ GenericUniformityAnalysisImpl()

template<typename ContextT>

llvm::GenericUniformityAnalysisImpl< ContextT >::GenericUniformityAnalysisImpl	(	const DominatorTreeT &	DT,
		const CycleInfoT &	CI,
		const TargetTransformInfo *	TTI )

inline

Definition at line 351 of file GenericUniformityImpl.h.

References CI, Context, F, getFunction(), and TTI.

Member Function Documentation

◆ addCustomUniformityCandidate()

template<typename ContextT>

void llvm::GenericUniformityAnalysisImpl< ContextT >::addCustomUniformityCandidate ( const InstructionT * I )

Add an instruction that requires custom uniformity analysis.

Definition at line 859 of file GenericUniformityImpl.h.

References CustomUniformityCandidates, and I.

Referenced by initialize().

◆ addUniformOverride()

template<typename ContextT>

void llvm::GenericUniformityAnalysisImpl< ContextT >::addUniformOverride ( const InstructionT & Instr )

Mark UniVal as a value that is always uniform.

Definition at line 853 of file GenericUniformityImpl.h.

Referenced by initialize().

◆ analyzeControlDivergence()

template<typename ContextT>

void llvm::GenericUniformityAnalysisImpl< ContextT >::analyzeControlDivergence ( const InstructionT & Term )

protected

Mark Term as divergent and push all Instructions that become divergent as a result on the worklist.

Definition at line 1097 of file GenericUniformityImpl.h.

References A(), assert(), B(), llvm::CallingConv::C, CI, Context, llvm::dbgs(), DivergentTermBlocks, llvm::getOutermostDivergentCycle(), llvm::insertIfNotContained(), LLVM_DEBUG, llvm::SmallVectorTemplateBase< T, bool >::push_back(), and llvm::sort().

Referenced by compute().

◆ compute()

template<typename ContextT>

void llvm::GenericUniformityAnalysisImpl< ContextT >::compute ( )

Propagate divergence to all instructions in the region.

Divergence is seeded by calls to markDivergent.

Definition at line 1153 of file GenericUniformityImpl.h.

References analyzeControlDivergence(), assert(), Context, llvm::dbgs(), HasBranchDivergence, I, isDivergent(), LLVM_DEBUG, and Worklist.

◆ getFunction()

template<typename ContextT>

const FunctionT & llvm::GenericUniformityAnalysisImpl< ContextT >::getFunction ( ) const

inline

Definition at line 358 of file GenericUniformityImpl.h.

References F.

Referenced by GenericUniformityAnalysisImpl().

◆ hasDivergentDefs() [1/3]

bool llvm::GenericUniformityAnalysisImpl< SSAContext >::hasDivergentDefs ( const Instruction & I ) const

Definition at line 22 of file UniformityAnalysis.cpp.

References I, and isDivergent().

◆ hasDivergentDefs() [2/3]

template<typename ContextT>

bool llvm::GenericUniformityAnalysisImpl< ContextT >::hasDivergentDefs ( const InstructionT & I ) const

References I.

Referenced by isDivergent().

◆ hasDivergentDefs() [3/3]

bool llvm::GenericUniformityAnalysisImpl< MachineSSAContext >::hasDivergentDefs ( const MachineInstr & I ) const

Definition at line 22 of file MachineUniformityAnalysis.cpp.

References I, isDivergent(), and op.

◆ hasDivergentTerminator()

template<typename ContextT>

bool llvm::GenericUniformityAnalysisImpl< ContextT >::hasDivergentTerminator ( const BlockT & B ) const

inline

Definition at line 410 of file GenericUniformityImpl.h.

References B(), and DivergentTermBlocks.

Referenced by print().

◆ initialize() [1/3]

template<typename ContextT>

void llvm::GenericUniformityAnalysisImpl< ContextT >::initialize ( )

◆ initialize() [2/3]

void llvm::GenericUniformityAnalysisImpl< SSAContext >::initialize ( )

Definition at line 68 of file UniformityAnalysis.cpp.

References addCustomUniformityCandidate(), addUniformOverride(), llvm::AlwaysUniform, llvm::Custom, llvm::Default, DivergentTermBlocks, F, I, instructions, llvm::NeverUniform, llvm::SmallVectorTemplateBase< T, bool >::push_back(), TTI, UniformValues, and Worklist.

◆ initialize() [3/3]

void llvm::GenericUniformityAnalysisImpl< MachineSSAContext >::initialize ( )

Definition at line 50 of file MachineUniformityAnalysis.cpp.

References addUniformOverride(), llvm::AlwaysUniform, block, llvm::Custom, llvm::Default, F, instr, markDivergent(), MI, llvm::NeverUniform, uniformity, and UniformValues.

◆ isAlwaysUniform()

template<typename ContextT>

bool llvm::GenericUniformityAnalysisImpl< ContextT >::isAlwaysUniform ( const InstructionT & Instr ) const

Whether Val will always return a uniform value regardless of its operands.

Definition at line 1183 of file GenericUniformityImpl.h.

Referenced by markDivergent().

◆ isCustomUniform()

template<typename ContextT>

bool llvm::GenericUniformityAnalysisImpl< ContextT >::isCustomUniform ( const InstructionT & I ) const

Check if an instruction with Custom uniformity can be proven uniform based on its operands.

This queries the target-specific callback.

References I.

Referenced by markDivergent().

◆ isDivergent() [1/2]

template<typename ContextT>

bool llvm::GenericUniformityAnalysisImpl< ContextT >::isDivergent ( const InstructionT & I ) const

inline

Definition at line 385 of file GenericUniformityImpl.h.

References DivergentTermBlocks, hasDivergentDefs(), and I.

Referenced by compute(), hasDivergentDefs(), hasDivergentDefs(), isDivergentUse(), isDivergentUse(), print(), and printDivergentArgs().

◆ isDivergent() [2/2]

template<typename ContextT>

bool llvm::GenericUniformityAnalysisImpl< ContextT >::isDivergent ( ConstValueRefT V ) const

inline

Whether Val is divergent at its definition.

When the target has no branch divergence, compute() is never called and everything is uniform. Otherwise, values not in UniformValues (e.g. newly created) are conservatively treated as divergent.

Definition at line 396 of file GenericUniformityImpl.h.

References HasBranchDivergence, and UniformValues.