Store Value Forwarding Optimization. More...

#include <StoreValueForwarding.hpp>

Inheritance diagram for jlm::llvm::StoreValueForwarding:

Collaboration diagram for jlm::llvm::StoreValueForwarding:

Classes
struct	Context

class	Statistics
	Store Value Forwarding Statistics class. More...

struct	TracedDelta

Public Member Functions
	~StoreValueForwarding () noexcept override

	StoreValueForwarding ()

	StoreValueForwarding (const StoreValueForwarding &)=delete

	StoreValueForwarding (StoreValueForwarding &&)=delete

StoreValueForwarding &	operator= (const StoreValueForwarding &)=delete

StoreValueForwarding &	operator= (StoreValueForwarding &&)=delete

void	Run (rvsdg::RvsdgModule &module, util::StatisticsCollector &statisticsCollector) override
	Perform RVSDG transformation.

Public Member Functions inherited from jlm::rvsdg::Transformation
virtual	~Transformation () noexcept

	Transformation (std::string_view Name)

const std::string_view &	GetName () const noexcept

void	Run (RvsdgModule &module)
	Perform RVSDG transformation.

Private Member Functions
void	traverseInterProceduralRegion (rvsdg::Region &region)

void	traverseIntraProceduralRegion (rvsdg::Region &region)

void	processLoad (rvsdg::SimpleNode &loadNode)

void	processLoadWithoutMemoryStates (rvsdg::SimpleNode &loadNode)

std::optional< TracedDelta >	traceLoadWithoutMemoryStates (const rvsdg::SimpleNode &loadNode)

void	forwardLoadWithoutMemoryStates (rvsdg::SimpleNode &loadNode, const TracedDelta &tracedDelta)

void	processLoadWithMemoryStates (rvsdg::SimpleNode &loadNode)

void	forwardValueOrigins (LoadTracingInfo &tracingInfo)

rvsdg::Output &	getValueOriginOutput (ValueOrigin storeValueOrigin, rvsdg::Region &targetRegion, LoadTracingInfo &tracingInfo)

void	connectUnroutedLoopPosts (LoadTracingInfo &tracingInfo)

rvsdg::Output &	routeOutputToRegion (rvsdg::Output &output, rvsdg::Region &region)

Private Attributes
std::unique_ptr< Context >	context_

Detailed Description

Store Value Forwarding Optimization.

Store Value Forwarding is an optimization that forwards store values to eliminate redundant loads.

Definition at line 30 of file StoreValueForwarding.hpp.

Constructor & Destructor Documentation

◆ ~StoreValueForwarding()

jlm::llvm::StoreValueForwarding::~StoreValueForwarding ( )

overridedefaultnoexcept

◆ StoreValueForwarding() [1/3]

jlm::llvm::StoreValueForwarding::StoreValueForwarding ( )

Definition at line 237 of file StoreValueForwarding.cpp.

◆ StoreValueForwarding() [2/3]

jlm::llvm::StoreValueForwarding::StoreValueForwarding ( const StoreValueForwarding & )

delete

◆ StoreValueForwarding() [3/3]

jlm::llvm::StoreValueForwarding::StoreValueForwarding ( StoreValueForwarding && )

delete

Member Function Documentation

◆ connectUnroutedLoopPosts()

void jlm::llvm::StoreValueForwarding::connectUnroutedLoopPosts ( LoadTracingInfo & tracingInfo )

private

In getValueOriginOutput(), all loop variables are created as invariant, to avoid recursive function calls looping around the graph. Instead, the post results of all created loop variables are added to a queue, and properly diverted to their correct origins by this function.

Definition at line 1492 of file StoreValueForwarding.cpp.

◆ forwardLoadWithoutMemoryStates()

void jlm::llvm::StoreValueForwarding::forwardLoadWithoutMemoryStates	(	rvsdg::SimpleNode &	loadNode,
		const TracedDelta &	tracedDelta
	)

private

Forwards a traced LoadNonVolatileOperation node without memory states.

Parameters

loadNode	The LoadNonVolatileOperation node to handle.
tracedDelta	The TracedDelta information of `loadNode`.

Definition at line 1301 of file StoreValueForwarding.cpp.

◆ forwardValueOrigins()

void jlm::llvm::StoreValueForwarding::forwardValueOrigins ( LoadTracingInfo & tracingInfo )

private

Performs store value forwarding to the load node represented by the given tracingInfo. Uses the metadata stored during tracing to replace the value output of the load node with the last value that was stored to the memory loaded by it.

Parameters

tracingInfo the metadata created during store value origin tracing.

Definition at line 1338 of file StoreValueForwarding.cpp.

◆ getValueOriginOutput()

rvsdg::Output & jlm::llvm::StoreValueForwarding::getValueOriginOutput	(	ValueOrigin	storeValueOrigin,
		rvsdg::Region &	targetRegion,
		LoadTracingInfo &	tracingInfo
	)

private

Gets an output providing the value stored at the given storeValueOrigin. The returned output is in the specified targetRegion. It must be the same region as the storeValueOrigin itself, or a parent region. Getting it may involve routing and creating new structural node inputs and outputs.

Parameters

storeValueOrigin	the origin of the last stored value along some memory state.
targetRegion	the region the returned output should be in.
tracingInfo	the metadata created during store value origin tracing.

Returns: the rvsdg output providing the stored value in the given region.

Definition at line 1368 of file StoreValueForwarding.cpp.

◆ operator=() [1/2]

StoreValueForwarding & jlm::llvm::StoreValueForwarding::operator= ( const StoreValueForwarding & )

delete

◆ operator=() [2/2]

StoreValueForwarding & jlm::llvm::StoreValueForwarding::operator= ( StoreValueForwarding && )

delete

◆ processLoad()

void jlm::llvm::StoreValueForwarding::processLoad ( rvsdg::SimpleNode & loadNode )

private

Process a non-volatile load node during traversal

Parameters

loadNode the load node to handle

Definition at line 983 of file StoreValueForwarding.cpp.

◆ processLoadWithMemoryStates()

void jlm::llvm::StoreValueForwarding::processLoadWithMemoryStates ( rvsdg::SimpleNode & loadNode )

private

Process a LoadNonVolatileOperation node with no memory states during traversal

Parameters

loadNode The LoadNonVolatileOperation node to handle

Definition at line 1000 of file StoreValueForwarding.cpp.

◆ processLoadWithoutMemoryStates()

void jlm::llvm::StoreValueForwarding::processLoadWithoutMemoryStates ( rvsdg::SimpleNode & loadNode )

private

Process a LoadNonVolatileOperation node with memory states during traversal

Parameters

loadNode The LoadNonVolatileOperation node to handle

Definition at line 1026 of file StoreValueForwarding.cpp.

◆ routeOutputToRegion()

rvsdg::Output & jlm::llvm::StoreValueForwarding::routeOutputToRegion	(	rvsdg::Output &	output,
		rvsdg::Region &	region
	)

private

Helper for routing outputs that memoizes the routing to avoid creating duplicate inputs and outputs in structural nodes. The output must be in the region, or in an ancestor of the region.

Parameters

output	the output to route
region	the destination of the routing

Returns: an output inside region that provides the same value as output

Definition at line 1514 of file StoreValueForwarding.cpp.

◆ Run()

void jlm::llvm::StoreValueForwarding::Run	(	rvsdg::RvsdgModule &	module,
		util::StatisticsCollector &	statisticsCollector
	)

overridevirtual

Perform RVSDG transformation.

Note: This method is expected to be called multiple times. An implementation is required to reset the objects' internal state to ensure correct behavior after every invocation.

Parameters

module	RVSDG module the transformation is performed on.
statisticsCollector	Statistics collector for collecting transformation statistics.

Implements jlm::rvsdg::Transformation.

Definition at line 1603 of file StoreValueForwarding.cpp.

◆ traceLoadWithoutMemoryStates()

std::optional< StoreValueForwarding::TracedDelta > jlm::llvm::StoreValueForwarding::traceLoadWithoutMemoryStates ( const rvsdg::SimpleNode & loadNode )

private

Try to trace a LoadNonVolatileOperation node without memory states to a delta node.

Parameters

loadNode The LoadNonVolatileOperation node to handle

Returns: The TracedDelta information if tracing was successful, otherwise std::nullopt.

Definition at line 1045 of file StoreValueForwarding.cpp.

◆ traverseInterProceduralRegion()

void jlm::llvm::StoreValueForwarding::traverseInterProceduralRegion ( rvsdg::Region & region )

private

Traverse the given inter-procedural region

Parameters

region the region to traverse

Definition at line 242 of file StoreValueForwarding.cpp.

◆ traverseIntraProceduralRegion()

void jlm::llvm::StoreValueForwarding::traverseIntraProceduralRegion ( rvsdg::Region & region )

private

Traverse the given intra-procedural region

Parameters

region the region to traverse

Definition at line 269 of file StoreValueForwarding.cpp.

Member Data Documentation

◆ context_

std::unique_ptr<Context> jlm::llvm::StoreValueForwarding::context_

private

Definition at line 174 of file StoreValueForwarding.hpp.

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

jlm/llvm/opt/StoreValueForwarding.hpp
jlm/llvm/opt/StoreValueForwarding.cpp

Classes

Public Member Functions

Private Member Functions

Private Attributes

Detailed Description

Constructor & Destructor Documentation

◆ ~StoreValueForwarding()

◆ StoreValueForwarding() [1/3]

◆ StoreValueForwarding() [2/3]

◆ StoreValueForwarding() [3/3]

Member Function Documentation

◆ connectUnroutedLoopPosts()

◆ forwardLoadWithoutMemoryStates()

◆ forwardValueOrigins()

◆ getValueOriginOutput()

◆ operator=() [1/2]

◆ operator=() [2/2]

◆ processLoad()

◆ processLoadWithMemoryStates()

◆ processLoadWithoutMemoryStates()

◆ routeOutputToRegion()

◆ Run()

◆ traceLoadWithoutMemoryStates()

◆ traverseInterProceduralRegion()

◆ traverseIntraProceduralRegion()

Member Data Documentation

◆ context_