jlm::llvm::CommonNodeElimination::Context Class Reference

Classes
struct	CongruenceSet

Public Types
using	CongruenceSetIndex = size_t

Public Member Functions
CongruenceSetIndex	numCongruenceSets () const
CongruenceSetIndex	tryGetSetFor (const rvsdg::Output &output) const
CongruenceSetIndex	getSetFor (const rvsdg::Output &output) const
bool	hasSet (const rvsdg::Output &output) const
CongruenceSetIndex	getOrCreateSetForLeader (const rvsdg::Output &leader)
const rvsdg::Output &	getLeader (CongruenceSetIndex index) const
void	addFollower (CongruenceSetIndex index, const rvsdg::Output &follower)
const util::HashSet< const rvsdg::Output * > &	getFollowers (CongruenceSetIndex index) const

Static Public Attributes
static constexpr auto	NoCongruenceSetIndex = std::numeric_limits<CongruenceSetIndex>::max()

Private Attributes
std::vector< CongruenceSet >	sets_
std::unordered_map< const rvsdg::Output *, CongruenceSetIndex >	congruenceSetMapping_

Detailed Description

Class representing congruence sets over outputs. Different outputs can be grouped together into congruence sets, where all members of a set are considered identical.

One output per set is the leader, and the rest are followers. During analysis of loops, outputs can be speculatively placed in the same congruence set. Later passes can then quickly verify if a outputs does not belong, by comparing against only the congruence set leader.

Definition at line 76 of file CommonNodeElimination.cpp.

Member Typedef Documentation

CongruenceSetIndex

using jlm::llvm::CommonNodeElimination::Context::CongruenceSetIndex = size_t

Definition at line 107 of file CommonNodeElimination.cpp.

Member Function Documentation

addFollower()

void jlm::llvm::CommonNodeElimination::Context::addFollower ( CongruenceSetIndex  index, const rvsdg::Output &  follower  )

inline

Makes the given output a follower of the congruence set with the given index. If output already follows the congruence set, this is a no-op If output already follows a different congruence set, it is moved. output can not be the leader of a congruence set.

Parameters

index	the index of the congruence set to follow
follower	the output that should become a follower

Definition at line 216 of file CommonNodeElimination.cpp.

getFollowers()

const util::HashSet<const rvsdg::Output *>& jlm::llvm::CommonNodeElimination::Context::getFollowers ( CongruenceSetIndex  index ) const

inline

Gets the set of followers in the congruence set with the given index.

Parameters

index

the index of the congruence set

Returns

the followers

Definition at line 249 of file CommonNodeElimination.cpp.

getLeader()

const rvsdg::Output& jlm::llvm::CommonNodeElimination::Context::getLeader ( CongruenceSetIndex  index ) const

inline

Gets the leader of the congruence set with the given index.

Parameters

index

the index of the congruence set

Returns

the output that is the leader of the set

Definition at line 201 of file CommonNodeElimination.cpp.

getOrCreateSetForLeader()

CongruenceSetIndex jlm::llvm::CommonNodeElimination::Context::getOrCreateSetForLeader ( const rvsdg::Output &  leader )

inline

Creates a new congruence set, in which the given leader becomes the leader. If leader already belongs to a congruence set as a follower, it is removed from that set. If leader is already a leader of a set, its index is returned, and this is a no-op.

Parameters

leader

the output that should lead a congruence set

Returns

the index of the congruence set led by the given leader

Definition at line 171 of file CommonNodeElimination.cpp.

getSetFor()

CongruenceSetIndex jlm::llvm::CommonNodeElimination::Context::getSetFor ( const rvsdg::Output &  output ) const

inline

Gets the index of the congruence set representing the given output.

Parameters

output

the output

Returns

the index of the congruence set the output belongs to

Exceptions

std::logic_error

if the output does not belong to a congruence set

Definition at line 144 of file CommonNodeElimination.cpp.

hasSet()

bool jlm::llvm::CommonNodeElimination::Context::hasSet ( const rvsdg::Output &  output ) const

inline

Checks if the given output is associated with a congruence set.

Parameters

output

the output

Returns

true if the output is associated with a congruence set, false otherwise

Definition at line 158 of file CommonNodeElimination.cpp.

numCongruenceSets()

CongruenceSetIndex jlm::llvm::CommonNodeElimination::Context::numCongruenceSets ( ) const

inline

Returns

the number of congruence sets in the data structure. Any congruence set that already exists when calling this method is guaranteed to have a CongruenceSetIndex strictly less than the returned value.

Definition at line 116 of file CommonNodeElimination.cpp.

tryGetSetFor()

CongruenceSetIndex jlm::llvm::CommonNodeElimination::Context::tryGetSetFor ( const rvsdg::Output &  output ) const

inline

Gets the index of the congruence set representing the given output, if it has one.

Parameters

output

the output

Returns

the index of the congruence set if the output belongs to one, otherwise NoCongruenceSetIndex.

Definition at line 128 of file CommonNodeElimination.cpp.

Member Data Documentation

congruenceSetMapping_

std::unordered_map<const rvsdg::Output *, CongruenceSetIndex> jlm::llvm::CommonNodeElimination::Context::congruenceSetMapping_

private

Definition at line 259 of file CommonNodeElimination.cpp.

NoCongruenceSetIndex

constexpr auto jlm::llvm::CommonNodeElimination::Context::NoCongruenceSetIndex = std::numeric_limits<CongruenceSetIndex>::max()

staticconstexpr

Definition at line 108 of file CommonNodeElimination.cpp.

sets_

std::vector<CongruenceSet> jlm::llvm::CommonNodeElimination::Context::sets_

private

Definition at line 257 of file CommonNodeElimination.cpp.

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

• jlm/llvm/opt/CommonNodeElimination.cpp