jlm::llvm::LoadTracingInfo Class Reference

Collaboration diagram for jlm::llvm::LoadTracingInfo:

Public Member Functions
	LoadTracingInfo (rvsdg::SimpleNode &loadNode, OutputTracer &tracer, aa::AliasAnalysis &aliasAnalysis)
bool	traceAllMemoryStateInputs ()

Public Attributes
rvsdg::SimpleNode &	loadNode
rvsdg::Output *	loadedAddress
std::shared_ptr< const rvsdg::Type >	loadedType
size_t	loadedTypeSize
OutputTracer &	tracer
aa::AliasAnalysis &	aliasAnalysis
size_t	numNoAliasAnalysisQueries = 0
size_t	numMayAliasAnalysisQueries = 0
size_t	numMustAliasAnalysisQueries = 0
std::unordered_map< rvsdg::SimpleNode *, StoreNodeInfo >	storeNodeInfo
std::unordered_map< rvsdg::Input *, StoreValueOrigin >	lastStoreBeforeInput
std::unordered_map< rvsdg::Node *, StoreValueOrigin >	lastStoreBeforeNode
std::unordered_map< rvsdg::Region *, StoreValueOrigin >	lastStoreInRegion
util::HashSet< rvsdg::Input * >	loopVarPostsToTrace
std::unordered_map< rvsdg::GammaNode *, rvsdg::Output * >	createdExitVars
std::unordered_map< rvsdg::ThetaNode *, rvsdg::ThetaNode::LoopVar >	createdLoopVars
std::queue< rvsdg::Input * >	unroutedLoopVarPosts

Private Member Functions
aa::AliasAnalysis::AliasQueryResponse	queryAliasAnalysis (rvsdg::SimpleNode &storeNode)
StoreValueOrigin	getLastStoreBeforeInput (rvsdg::Input &input)
StoreValueOrigin	getLastStoreBeforeInputInternal (rvsdg::Input &input)
void	updateAliasAnalysisQueryCounters (aa::AliasAnalysis::AliasQueryResponse response)

Detailed Description

Helper class holding info during tracing of the memory states going to a given load node. Can trace into structural nodes, and keep track of separate store nodes for separate regions. If all branches lead to a store that can be forwarded, forwarding can be performed.

Definition at line 320 of file StoreValueForwarding.cpp.

Constructor & Destructor Documentation

LoadTracingInfo()

jlm::llvm::LoadTracingInfo::LoadTracingInfo ( rvsdg::SimpleNode &  loadNode, OutputTracer &  tracer, aa::AliasAnalysis &  aliasAnalysis  )

inline

Definition at line 323 of file StoreValueForwarding.cpp.

Member Function Documentation

getLastStoreBeforeInput()

StoreValueOrigin jlm::llvm::LoadTracingInfo::getLastStoreBeforeInput ( rvsdg::Input &  input )

inlineprivate

Attempts to trace the given memory state input back to a store node that can be forwarded. If a store node that may alias the load is encountered, unknown is returned. If structural nodes are encountered, all branches are traced. If any of the branches are not traceable, unknown is returned. If the branches lead to different store nodes, the structural node itself is returned.

During tracing, the class keeps track of the last store before nodes and region exits. If tracing different memory state chains lead to different "last store node before X", store forwarding is not possible, and unknown is returned to terminate early.

Parameters

input

the memory state input to trace from

Returns

the last node that stores to the memory loaded by the loadNode, before the input.

Definition at line 421 of file StoreValueForwarding.cpp.

getLastStoreBeforeInputInternal()

StoreValueOrigin jlm::llvm::LoadTracingInfo::getLastStoreBeforeInputInternal ( rvsdg::Input &  input )

inlineprivate

Definition at line 457 of file StoreValueForwarding.cpp.

queryAliasAnalysis()

aa::AliasAnalysis::AliasQueryResponse jlm::llvm::LoadTracingInfo::queryAliasAnalysis ( rvsdg::SimpleNode &  storeNode )

inlineprivate

Performs a simple alias analysis query between the loadNode and the given store node, to determine if they read and write from the same exact address, possibly interfere, or if the operations are guaranteed to be fully independent.

Parameters

storeNode

the StoreOperation node

Definition at line 387 of file StoreValueForwarding.cpp.

traceAllMemoryStateInputs()

bool jlm::llvm::LoadTracingInfo::traceAllMemoryStateInputs ( )

inline

Performs tracing of memory states to find store node(s) that can be forwarded to the load. If tracing leads to nodes that may or may not clobber the load, or if different memory state inputs lead to different store node(s), store value forwarding is not possible, and false is returned. Different branches of structural nodes can lead to different store nodes, as long as all memory states lead to the same store node in each branch.

Returns

true iff all memory state inputs could be traced to the same store node(s).

Definition at line 347 of file StoreValueForwarding.cpp.

updateAliasAnalysisQueryCounters()

void jlm::llvm::LoadTracingInfo::updateAliasAnalysisQueryCounters ( aa::AliasAnalysis::AliasQueryResponse  response )

inlineprivate

Definition at line 627 of file StoreValueForwarding.cpp.

Member Data Documentation

aliasAnalysis

aa::AliasAnalysis& jlm::llvm::LoadTracingInfo::aliasAnalysis

Definition at line 652 of file StoreValueForwarding.cpp.

createdExitVars

std::unordered_map<rvsdg::GammaNode *, rvsdg::Output *> jlm::llvm::LoadTracingInfo::createdExitVars

Definition at line 676 of file StoreValueForwarding.cpp.

createdLoopVars

std::unordered_map<rvsdg::ThetaNode *, rvsdg::ThetaNode::LoopVar> jlm::llvm::LoadTracingInfo::createdLoopVars

Definition at line 678 of file StoreValueForwarding.cpp.

lastStoreBeforeInput

std::unordered_map<rvsdg::Input *, StoreValueOrigin> jlm::llvm::LoadTracingInfo::lastStoreBeforeInput

Definition at line 663 of file StoreValueForwarding.cpp.

lastStoreBeforeNode

std::unordered_map<rvsdg::Node *, StoreValueOrigin> jlm::llvm::LoadTracingInfo::lastStoreBeforeNode

Definition at line 665 of file StoreValueForwarding.cpp.

lastStoreInRegion

std::unordered_map<rvsdg::Region *, StoreValueOrigin> jlm::llvm::LoadTracingInfo::lastStoreInRegion

Definition at line 668 of file StoreValueForwarding.cpp.

loadedAddress

rvsdg::Output* jlm::llvm::LoadTracingInfo::loadedAddress

Definition at line 647 of file StoreValueForwarding.cpp.

loadedType

std::shared_ptr<const rvsdg::Type> jlm::llvm::LoadTracingInfo::loadedType

Definition at line 648 of file StoreValueForwarding.cpp.

loadedTypeSize

size_t jlm::llvm::LoadTracingInfo::loadedTypeSize

Definition at line 649 of file StoreValueForwarding.cpp.

loadNode

rvsdg::SimpleNode& jlm::llvm::LoadTracingInfo::loadNode

Definition at line 646 of file StoreValueForwarding.cpp.

loopVarPostsToTrace

util::HashSet<rvsdg::Input *> jlm::llvm::LoadTracingInfo::loopVarPostsToTrace

Definition at line 673 of file StoreValueForwarding.cpp.

numMayAliasAnalysisQueries

size_t jlm::llvm::LoadTracingInfo::numMayAliasAnalysisQueries = 0

Definition at line 656 of file StoreValueForwarding.cpp.

numMustAliasAnalysisQueries

size_t jlm::llvm::LoadTracingInfo::numMustAliasAnalysisQueries = 0

Definition at line 657 of file StoreValueForwarding.cpp.

numNoAliasAnalysisQueries

size_t jlm::llvm::LoadTracingInfo::numNoAliasAnalysisQueries = 0

Definition at line 655 of file StoreValueForwarding.cpp.

storeNodeInfo

std::unordered_map<rvsdg::SimpleNode *, StoreNodeInfo> jlm::llvm::LoadTracingInfo::storeNodeInfo

Definition at line 660 of file StoreValueForwarding.cpp.

tracer

OutputTracer& jlm::llvm::LoadTracingInfo::tracer

Definition at line 651 of file StoreValueForwarding.cpp.

unroutedLoopVarPosts

std::queue<rvsdg::Input *> jlm::llvm::LoadTracingInfo::unroutedLoopVarPosts

Definition at line 680 of file StoreValueForwarding.cpp.

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

• jlm/llvm/opt/StoreValueForwarding.cpp