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implementing some new functionality to bitvecotr

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This commit is contained in:
Jiri Pittner
2023-12-27 23:24:13 +01:00
parent eafcfbdd00
commit c428d4650c
5 changed files with 111 additions and 16 deletions
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24
bitvector.h
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@@ -20,13 +20,14 @@
#define _BITVECTOR_H_
#include "vec.h"
#include <stdint.h>
namespace LA {
//compressed storage of large bit vectors
//any reasonable compiler changes the dividions and modulos to shift/and instructions
//let's now use 64-bit blocks exclusively
typedef unsigned long bitvector_block; //should be automatically portable and efficiently use wordlength of each machine (32 vs 64)
typedef uint64_t bitvector_block;
#define blockbits (8*sizeof(bitvector_block))
@@ -47,19 +48,21 @@ public:
//operator= seems to be correctly synthetized by the compiler
//override dereferencing to address single bits, is however possible
//only in the const context (otherwise we would have to define a type which, when assigned to, changes a single bit - possible but probably inefficient)
void resize(const unsigned int n) {NRVec<bitvector_block>::resize((n+blockbits-1)/blockbits); modulo=n%blockbits;};
void resize(const unsigned int n, bool preserve=false) {NRVec<bitvector_block>::resize((n+blockbits-1)/blockbits,preserve); modulo=n%blockbits;};
unsigned int size() const {return (nn*blockbits)-blockbits+(modulo?modulo:blockbits);};
//arguments must be unsigned to keep the resulting assembly code simple and efficient
const bool operator[](const unsigned int i) const {return (v[i/blockbits] >>(i%blockbits))&1UL;};
const bool get(const unsigned int i) const {return (*this)[i];};
bitvector_block getblock(const unsigned int i) const {return v[i];}; //integer interpretation
void setblock(const unsigned int i, const bitvector_block b) {v[i]=b;};
int getblocksize() const {return 8*sizeof(bitvector_block);};
void set(const unsigned int i) {v[i/blockbits] |= (1UL<<(i%blockbits));};
void reset(const unsigned int i) {v[i/blockbits] &= ~(1UL<<(i%blockbits));};
const bool get(const unsigned int i) {return (v[i/blockbits] >>(i%blockbits))&1UL;};
const bool assign(const unsigned int i, const bool r) {if(r) set(i); else reset(i); return r;};
void clear() {copyonwrite(true); memset(v,0,nn*sizeof(bitvector_block));};
void fill() {memset(v,0xff,nn*sizeof(bitvector_block));};
bool iszero() const {for(int i=0; i<nn; ++i) if(v[i]) return false; return true;};
void randomize();
bool operator!=(const bitvector &rhs) const;
bool operator==(const bitvector &rhs) const {return !(*this != rhs);};
bool operator>(const bitvector &rhs) const;
@@ -70,13 +73,22 @@ public:
bitvector& operator&=(const bitvector &rhs);
bitvector& operator|=(const bitvector &rhs);
bitvector& operator^=(const bitvector &rhs);
bitvector& operator+=(const bitvector &rhs) {return (*this)^=rhs;}; //addition modulo 2
bitvector& operator-=(const bitvector &rhs) {return (*this)^=rhs;}; //subtraction modulo 2
bitvector operator&(const bitvector &rhs) const {return bitvector(*this) &= rhs;};
bitvector operator|(const bitvector &rhs) const {return bitvector(*this) |= rhs;};
bitvector operator^(const bitvector &rhs) const {return bitvector(*this) ^= rhs;};
bitvector operator+(const bitvector &rhs) const {return *this ^ rhs;}; //addition modulo 2
bitvector operator-(const bitvector &rhs) const {return *this ^ rhs;}; //subtraction modulo 2
unsigned int operator%(const bitvector &y) const; //number of differing bits
unsigned int population(const unsigned int before=0) const; //number of 1's
//extended, truncated const i.e. not on *this but return new entity, take care of modulo's bits
//logical shifts <<= >>= << >> not implemented yet
//logical shifts
bitvector& operator>>=(unsigned int i);
bitvector& leftshift(unsigned int i, bool autoresize=false);
bitvector& operator<<=(unsigned int i) {return leftshift(i,true);};
bitvector operator>>(unsigned int i) {bitvector r(*this); return r>>=i;};
bitvector operator<<(unsigned int i) {bitvector r(*this); return r<<=i;};
//logical rotations not implemented yet
//unformatted file IO
void read(int fd, bool dimensions=1, bool transp=0);