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llvm::SparseBitVectorElement< ElementSize > Struct Template Reference

#include <SparseBitVector.h>

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List of all members.

Public Types

enum  { BITWORD_SIZE = sizeof(BitWord) * CHAR_BIT, BITWORDS_PER_ELEMENT = (ElementSize + BITWORD_SIZE - 1) / BITWORD_SIZE, BITS_PER_ELEMENT = ElementSize }
typedef unsigned long BitWord
typedef unsigned size_type

Public Member Functions

 SparseBitVectorElement (unsigned Idx)
bool operator== (const SparseBitVectorElement &RHS) const
bool operator!= (const SparseBitVectorElement &RHS) const
BitWord word (unsigned Idx) const
unsigned index () const
bool empty () const
void set (unsigned Idx)
bool test_and_set (unsigned Idx)
void reset (unsigned Idx)
bool test (unsigned Idx) const
size_type count () const
int find_first () const
 find_first - Returns the index of the first set bit.
int find_next (unsigned Curr) const
bool unionWith (const SparseBitVectorElement &RHS)
bool intersects (const SparseBitVectorElement &RHS) const
bool intersectWith (const SparseBitVectorElement &RHS, bool &BecameZero)
bool intersectWithComplement (const SparseBitVectorElement &RHS, bool &BecameZero)
void intersectWithComplement (const SparseBitVectorElement &RHS1, const SparseBitVectorElement &RHS2, bool &BecameZero)

Friends

struct ilist_sentinel_traits< SparseBitVectorElement >

Detailed Description

template<unsigned ElementSize = 128>
struct llvm::SparseBitVectorElement< ElementSize >

SparseBitVector is an implementation of a bitvector that is sparse by only storing the elements that have non-zero bits set. In order to make this fast for the most common cases, SparseBitVector is implemented as a linked list of SparseBitVectorElements. We maintain a pointer to the last SparseBitVectorElement accessed (in the form of a list iterator), in order to make multiple in-order test/set constant time after the first one is executed. Note that using vectors to store SparseBitVectorElement's does not work out very well because it causes insertion in the middle to take enormous amounts of time with a large amount of bits. Other structures that have better worst cases for insertion in the middle (various balanced trees, etc) do not perform as well in practice as a linked list with this iterator kept up to date. They are also significantly more memory intensive.

Definition at line 44 of file SparseBitVector.h.


Member Typedef Documentation

template<unsigned ElementSize = 128>
typedef unsigned long llvm::SparseBitVectorElement< ElementSize >::BitWord

Definition at line 47 of file SparseBitVector.h.

template<unsigned ElementSize = 128>
typedef unsigned llvm::SparseBitVectorElement< ElementSize >::size_type

Definition at line 48 of file SparseBitVector.h.


Member Enumeration Documentation

template<unsigned ElementSize = 128>
anonymous enum
Enumerator:
BITWORD_SIZE 
BITWORDS_PER_ELEMENT 
BITS_PER_ELEMENT 

Definition at line 49 of file SparseBitVector.h.


Constructor & Destructor Documentation

template<unsigned ElementSize = 128>
llvm::SparseBitVectorElement< ElementSize >::SparseBitVectorElement ( unsigned  Idx) [inline, explicit]

Member Function Documentation

template<unsigned ElementSize = 128>
size_type llvm::SparseBitVectorElement< ElementSize >::count ( ) const [inline]
template<unsigned ElementSize = 128>
bool llvm::SparseBitVectorElement< ElementSize >::empty ( ) const [inline]
template<unsigned ElementSize = 128>
int llvm::SparseBitVectorElement< ElementSize >::find_first ( ) const [inline]
template<unsigned ElementSize = 128>
int llvm::SparseBitVectorElement< ElementSize >::find_next ( unsigned  Curr) const [inline]

find_next - Returns the index of the next set bit starting from the "Curr" bit. Returns -1 if the next set bit is not found.

Definition at line 151 of file SparseBitVector.h.

References llvm::tgtok::Bits, llvm::SparseBitVectorElement< ElementSize >::BITS_PER_ELEMENT, llvm::SparseBitVectorElement< ElementSize >::BITWORD_SIZE, llvm::SparseBitVectorElement< ElementSize >::BITWORDS_PER_ELEMENT, llvm::countTrailingZeros(), and llvm_unreachable.

template<unsigned ElementSize = 128>
unsigned llvm::SparseBitVectorElement< ElementSize >::index ( ) const [inline]

Definition at line 92 of file SparseBitVector.h.

Referenced by llvm::SparseBitVector< ElementSize >::find_first().

template<unsigned ElementSize = 128>
bool llvm::SparseBitVectorElement< ElementSize >::intersects ( const SparseBitVectorElement< ElementSize > &  RHS) const [inline]
template<unsigned ElementSize = 128>
bool llvm::SparseBitVectorElement< ElementSize >::intersectWith ( const SparseBitVectorElement< ElementSize > &  RHS,
bool BecameZero 
) [inline]
template<unsigned ElementSize = 128>
bool llvm::SparseBitVectorElement< ElementSize >::intersectWithComplement ( const SparseBitVectorElement< ElementSize > &  RHS,
bool BecameZero 
) [inline]
template<unsigned ElementSize = 128>
void llvm::SparseBitVectorElement< ElementSize >::intersectWithComplement ( const SparseBitVectorElement< ElementSize > &  RHS1,
const SparseBitVectorElement< ElementSize > &  RHS2,
bool BecameZero 
) [inline]
template<unsigned ElementSize = 128>
bool llvm::SparseBitVectorElement< ElementSize >::operator!= ( const SparseBitVectorElement< ElementSize > &  RHS) const [inline]

Definition at line 82 of file SparseBitVector.h.

template<unsigned ElementSize = 128>
bool llvm::SparseBitVectorElement< ElementSize >::operator== ( const SparseBitVectorElement< ElementSize > &  RHS) const [inline]
template<unsigned ElementSize = 128>
void llvm::SparseBitVectorElement< ElementSize >::reset ( unsigned  Idx) [inline]
template<unsigned ElementSize = 128>
void llvm::SparseBitVectorElement< ElementSize >::set ( unsigned  Idx) [inline]
template<unsigned ElementSize = 128>
bool llvm::SparseBitVectorElement< ElementSize >::test ( unsigned  Idx) const [inline]
template<unsigned ElementSize = 128>
bool llvm::SparseBitVectorElement< ElementSize >::test_and_set ( unsigned  Idx) [inline]
template<unsigned ElementSize = 128>
bool llvm::SparseBitVectorElement< ElementSize >::unionWith ( const SparseBitVectorElement< ElementSize > &  RHS) [inline]
template<unsigned ElementSize = 128>
BitWord llvm::SparseBitVectorElement< ElementSize >::word ( unsigned  Idx) const [inline]

Friends And Related Function Documentation

template<unsigned ElementSize = 128>
friend struct ilist_sentinel_traits< SparseBitVectorElement > [friend]

Definition at line 60 of file SparseBitVector.h.


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