LLVM  6.0.0svn
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llvm::EquivalenceClasses< ElemTy > Class Template Reference

EquivalenceClasses - This represents a collection of equivalence classes and supports three efficient operations: insert an element into a class of its own, union two classes, and find the class for a given element. More...

#include "llvm/ADT/EquivalenceClasses.h"

Inheritance diagram for llvm::EquivalenceClasses< ElemTy >:
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Classes

class  member_iterator
 

Public Types

using iterator = typename std::set< ECValue >::const_iterator
 iterator* - Provides a way to iterate over all values in the set. More...
 

Public Member Functions

 EquivalenceClasses ()=default
 
 EquivalenceClasses (const EquivalenceClasses &RHS)
 
const EquivalenceClassesoperator= (const EquivalenceClasses &RHS)
 
iterator begin () const
 
iterator end () const
 
bool empty () const
 
member_iterator member_begin (iterator I) const
 
member_iterator member_end () const
 
iterator findValue (const ElemTy &V) const
 findValue - Return an iterator to the specified value. More...
 
const ElemTy & getLeaderValue (const ElemTy &V) const
 getLeaderValue - Return the leader for the specified value that is in the set. More...
 
const ElemTy & getOrInsertLeaderValue (const ElemTy &V)
 getOrInsertLeaderValue - Return the leader for the specified value that is in the set. More...
 
unsigned getNumClasses () const
 getNumClasses - Return the number of equivalence classes in this set. More...
 
iterator insert (const ElemTy &Data)
 insert - Insert a new value into the union/find set, ignoring the request if the value already exists. More...
 
member_iterator findLeader (iterator I) const
 findLeader - Given a value in the set, return a member iterator for the equivalence class it is in. More...
 
member_iterator findLeader (const ElemTy &V) const
 
member_iterator unionSets (const ElemTy &V1, const ElemTy &V2)
 union - Merge the two equivalence sets for the specified values, inserting them if they do not already exist in the equivalence set. More...
 
member_iterator unionSets (member_iterator L1, member_iterator L2)
 

Detailed Description

template<class ElemTy>
class llvm::EquivalenceClasses< ElemTy >

EquivalenceClasses - This represents a collection of equivalence classes and supports three efficient operations: insert an element into a class of its own, union two classes, and find the class for a given element.

In addition to these modification methods, it is possible to iterate over all of the equivalence classes and all of the elements in a class.

This implementation is an efficient implementation that only stores one copy of the element being indexed per entry in the set, and allows any arbitrary type to be indexed (as long as it can be ordered with operator<).

Here is a simple example using integers:

EquivalenceClasses<int> EC;
EC.unionSets(1, 2); // insert 1, 2 into the same set
EC.insert(4); EC.insert(5); // insert 4, 5 into own sets
EC.unionSets(5, 1); // merge the set for 1 with 5's set.
for (EquivalenceClasses<int>::iterator I = EC.begin(), E = EC.end();
I != E; ++I) { // Iterate over all of the equivalence sets.
if (!I->isLeader()) continue; // Ignore non-leader sets.
for (EquivalenceClasses<int>::member_iterator MI = EC.member_begin(I);
MI != EC.member_end(); ++MI) // Loop over members in this set.
cerr << *MI << " "; // Print member.
cerr << "\n"; // Finish set.
}

This example prints: 4 5 1 2

Definition at line 59 of file EquivalenceClasses.h.

Member Typedef Documentation

◆ iterator

template<class ElemTy>
using llvm::EquivalenceClasses< ElemTy >::iterator = typename std::set<ECValue>::const_iterator

iterator* - Provides a way to iterate over all values in the set.

Definition at line 145 of file EquivalenceClasses.h.

Constructor & Destructor Documentation

◆ EquivalenceClasses() [1/2]

template<class ElemTy>
llvm::EquivalenceClasses< ElemTy >::EquivalenceClasses ( )
default

◆ EquivalenceClasses() [2/2]

template<class ElemTy>
llvm::EquivalenceClasses< ElemTy >::EquivalenceClasses ( const EquivalenceClasses< ElemTy > &  RHS)
inline

Definition at line 124 of file EquivalenceClasses.h.

Member Function Documentation

◆ begin()

template<class ElemTy>
iterator llvm::EquivalenceClasses< ElemTy >::begin ( ) const
inline

◆ empty()

template<class ElemTy>
bool llvm::EquivalenceClasses< ElemTy >::empty ( ) const
inline

Definition at line 150 of file EquivalenceClasses.h.

◆ end()

template<class ElemTy>
iterator llvm::EquivalenceClasses< ElemTy >::end ( ) const
inline

◆ findLeader() [1/2]

template<class ElemTy>
member_iterator llvm::EquivalenceClasses< ElemTy >::findLeader ( iterator  I) const
inline

findLeader - Given a value in the set, return a member iterator for the equivalence class it is in.

This does the path-compression part that makes union-find "union findy". This returns an end iterator if the value is not in the equivalence class.

Definition at line 208 of file EquivalenceClasses.h.

Referenced by llvm::EquivalenceClasses< llvm::Instruction *>::findLeader(), llvm::EquivalenceClasses< llvm::Instruction *>::getLeaderValue(), llvm::EquivalenceClasses< llvm::Instruction *>::getOrInsertLeaderValue(), and llvm::EquivalenceClasses< llvm::Instruction *>::unionSets().

◆ findLeader() [2/2]

template<class ElemTy>
member_iterator llvm::EquivalenceClasses< ElemTy >::findLeader ( const ElemTy &  V) const
inline

Definition at line 212 of file EquivalenceClasses.h.

◆ findValue()

template<class ElemTy>
iterator llvm::EquivalenceClasses< ElemTy >::findValue ( const ElemTy &  V) const
inline

findValue - Return an iterator to the specified value.

If it does not exist, end() is returned.

Definition at line 164 of file EquivalenceClasses.h.

Referenced by llvm::RuntimePointerChecking::CheckingPtrGroup::addPointer(), and llvm::MemoryDepChecker::areDepsSafe().

◆ getLeaderValue()

template<class ElemTy>
const ElemTy& llvm::EquivalenceClasses< ElemTy >::getLeaderValue ( const ElemTy &  V) const
inline

getLeaderValue - Return the leader for the specified value that is in the set.

It is an error to call this method for a value that is not yet in the set. For that, call getOrInsertLeaderValue(V).

Definition at line 171 of file EquivalenceClasses.h.

Referenced by llvm::RuntimePointerChecking::CheckingPtrGroup::addPointer(), llvm::MemoryDepChecker::areDepsSafe(), and isNoWrap().

◆ getNumClasses()

template<class ElemTy>
unsigned llvm::EquivalenceClasses< ElemTy >::getNumClasses ( ) const
inline

getNumClasses - Return the number of equivalence classes in this set.

Note that this is a linear time operation.

Definition at line 188 of file EquivalenceClasses.h.

◆ getOrInsertLeaderValue()

template<class ElemTy>
const ElemTy& llvm::EquivalenceClasses< ElemTy >::getOrInsertLeaderValue ( const ElemTy &  V)
inline

getOrInsertLeaderValue - Return the leader for the specified value that is in the set.

If the member is not in the set, it is inserted, then returned.

Definition at line 180 of file EquivalenceClasses.h.

Referenced by llvm::computeMinimumValueSizes().

◆ insert()

template<class ElemTy>
iterator llvm::EquivalenceClasses< ElemTy >::insert ( const ElemTy &  Data)
inline

◆ member_begin()

template<class ElemTy>
member_iterator llvm::EquivalenceClasses< ElemTy >::member_begin ( iterator  I) const
inline

◆ member_end()

template<class ElemTy>
member_iterator llvm::EquivalenceClasses< ElemTy >::member_end ( ) const
inline

◆ operator=()

template<class ElemTy>
const EquivalenceClasses& llvm::EquivalenceClasses< ElemTy >::operator= ( const EquivalenceClasses< ElemTy > &  RHS)
inline

◆ unionSets() [1/2]

template<class ElemTy>
member_iterator llvm::EquivalenceClasses< ElemTy >::unionSets ( const ElemTy &  V1,
const ElemTy &  V2 
)
inline

union - Merge the two equivalence sets for the specified values, inserting them if they do not already exist in the equivalence set.

Definition at line 218 of file EquivalenceClasses.h.

Referenced by llvm::computeMinimumValueSizes(), isNoWrap(), llvm::EquivalenceClasses< llvm::Instruction *>::operator=(), and llvm::EquivalenceClasses< llvm::Instruction *>::unionSets().

◆ unionSets() [2/2]

template<class ElemTy>
member_iterator llvm::EquivalenceClasses< ElemTy >::unionSets ( member_iterator  L1,
member_iterator  L2 
)
inline

Definition at line 222 of file EquivalenceClasses.h.


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