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/********************* */
/*! \file integer_gmp_imp.h
** \verbatim
** Original author: Tim King
** Major contributors: Morgan Deters, Liana Hadarean
** Minor contributors (to current version): Dejan Jovanovic
** This file is part of the CVC4 project.
** Copyright (c) 2009-2014 New York University and The University of Iowa
** See the file COPYING in the top-level source directory for licensing
** information.\endverbatim
**
** \brief A multiprecision integer constant; wraps a GMP multiprecision
** integer.
**
** A multiprecision integer constant; wraps a GMP multiprecision integer.
**/
#include "cvc4_public.h"
#ifndef __CVC4__INTEGER_H
#define __CVC4__INTEGER_H
#include <string>
#include <iostream>
#include <limits>
#include "util/gmp_util.h"
#include "util/exception.h"
namespace CVC4 {
class Rational;
class CVC4_PUBLIC Integer {
private:
/**
* Stores the value of the rational is stored in a C++ GMP integer class.
* Using this instead of mpz_t allows for easier destruction.
*/
mpz_class d_value;
public:
/**
* Gets a reference to the gmp data that backs up the integer.
* Only accessible to friend classes.
*/
const mpz_class& get_mpz() const { return d_value; }
/**
* Constructs an Integer by copying a GMP C++ primitive.
*/
Integer(const mpz_class& val) : d_value(val) {}
/** Constructs a rational with the value 0. */
Integer() : d_value(0){}
/**
* Constructs a Integer from a C string.
* Throws std::invalid_argument if the string is not a valid rational.
* For more information about what is a valid rational string,
* see GMP's documentation for mpq_set_str().
*/
explicit Integer(const char* s, unsigned base = 10);
explicit Integer(const std::string& s, unsigned base = 10);
Integer(const Integer& q) : d_value(q.d_value) {}
Integer( signed int z) : d_value(z) {}
Integer(unsigned int z) : d_value(z) {}
Integer( signed long int z) : d_value(z) {}
Integer(unsigned long int z) : d_value(z) {}
#ifdef CVC4_NEED_INT64_T_OVERLOADS
Integer( int64_t z) : d_value(static_cast<long>(z)) {}
Integer(uint64_t z) : d_value(static_cast<unsigned long>(z)) {}
#endif /* CVC4_NEED_INT64_T_OVERLOADS */
~Integer() {}
Integer& operator=(const Integer& x){
if(this == &x) return *this;
d_value = x.d_value;
return *this;
}
bool operator==(const Integer& y) const {
return d_value == y.d_value;
}
Integer operator-() const {
return Integer(-(d_value));
}
bool operator!=(const Integer& y) const {
return d_value != y.d_value;
}
bool operator< (const Integer& y) const {
return d_value < y.d_value;
}
bool operator<=(const Integer& y) const {
return d_value <= y.d_value;
}
bool operator> (const Integer& y) const {
return d_value > y.d_value;
}
bool operator>=(const Integer& y) const {
return d_value >= y.d_value;
}
Integer operator+(const Integer& y) const {
return Integer( d_value + y.d_value );
}
Integer& operator+=(const Integer& y) {
d_value += y.d_value;
return *this;
}
Integer operator-(const Integer& y) const {
return Integer( d_value - y.d_value );
}
Integer& operator-=(const Integer& y) {
d_value -= y.d_value;
return *this;
}
Integer operator*(const Integer& y) const {
return Integer( d_value * y.d_value );
}
Integer& operator*=(const Integer& y) {
d_value *= y.d_value;
return *this;
}
Integer bitwiseOr(const Integer& y) const {
mpz_class result;
mpz_ior(result.get_mpz_t(), d_value.get_mpz_t(), y.d_value.get_mpz_t());
return Integer(result);
}
Integer bitwiseAnd(const Integer& y) const {
mpz_class result;
mpz_and(result.get_mpz_t(), d_value.get_mpz_t(), y.d_value.get_mpz_t());
return Integer(result);
}
Integer bitwiseXor(const Integer& y) const {
mpz_class result;
mpz_xor(result.get_mpz_t(), d_value.get_mpz_t(), y.d_value.get_mpz_t());
return Integer(result);
}
Integer bitwiseNot() const {
mpz_class result;
mpz_com(result.get_mpz_t(), d_value.get_mpz_t());
return Integer(result);
}
/**
* Return this*(2^pow).
*/
Integer multiplyByPow2(uint32_t pow) const{
mpz_class result;
mpz_mul_2exp(result.get_mpz_t(), d_value.get_mpz_t(), pow);
return Integer( result );
}
/**
* Returns the Integer obtained by setting the ith bit of the
* current Integer to 1.
*/
Integer setBit(uint32_t i) const {
mpz_class res = d_value;
mpz_setbit(res.get_mpz_t(), i);
return Integer(res);
}
bool isBitSet(uint32_t i) const {
return !extractBitRange(1, i).isZero();
}
/**
* Returns the integer with the binary representation of size bits
* extended with amount 1's
*/
Integer oneExtend(uint32_t size, uint32_t amount) const {
// check that the size is accurate
DebugCheckArgument((*this) < Integer(1).multiplyByPow2(size), size);
mpz_class res = d_value;
for (unsigned i = size; i < size + amount; ++i) {
mpz_setbit(res.get_mpz_t(), i);
}
return Integer(res);
}
uint32_t toUnsignedInt() const {
return mpz_get_ui(d_value.get_mpz_t());
}
/** See GMP Documentation. */
Integer extractBitRange(uint32_t bitCount, uint32_t low) const {
// bitCount = high-low+1
uint32_t high = low + bitCount-1;
//— Function: void mpz_fdiv_r_2exp (mpz_t r, mpz_t n, mp_bitcnt_t b)
mpz_class rem, div;
mpz_fdiv_r_2exp(rem.get_mpz_t(), d_value.get_mpz_t(), high+1);
mpz_fdiv_q_2exp(div.get_mpz_t(), rem.get_mpz_t(), low);
return Integer(div);
}
/**
* Returns the floor(this / y)
*/
Integer floorDivideQuotient(const Integer& y) const {
mpz_class q;
mpz_fdiv_q(q.get_mpz_t(), d_value.get_mpz_t(), y.d_value.get_mpz_t());
return Integer( q );
}
/**
* Returns r == this - floor(this/y)*y
*/
Integer floorDivideRemainder(const Integer& y) const {
mpz_class r;
mpz_fdiv_r(r.get_mpz_t(), d_value.get_mpz_t(), y.d_value.get_mpz_t());
return Integer( r );
}
/**
* Computes a floor quotient and remainder for x divided by y.
*/
static void floorQR(Integer& q, Integer& r, const Integer& x, const Integer& y) {
mpz_fdiv_qr(q.d_value.get_mpz_t(), r.d_value.get_mpz_t(), x.d_value.get_mpz_t(), y.d_value.get_mpz_t());
}
/**
* Returns the ceil(this / y)
*/
Integer ceilingDivideQuotient(const Integer& y) const {
mpz_class q;
mpz_cdiv_q(q.get_mpz_t(), d_value.get_mpz_t(), y.d_value.get_mpz_t());
return Integer( q );
}
/**
* Returns the ceil(this / y)
*/
Integer ceilingDivideRemainder(const Integer& y) const {
mpz_class r;
mpz_cdiv_r(r.get_mpz_t(), d_value.get_mpz_t(), y.d_value.get_mpz_t());
return Integer( r );
}
/**
* Computes a quoitent and remainder according to Boute's Euclidean definition.
* euclidianDivideQuotient, euclidianDivideRemainder.
*
* Boute, Raymond T. (April 1992).
* The Euclidean definition of the functions div and mod.
* ACM Transactions on Programming Languages and Systems (TOPLAS)
* ACM Press. 14 (2): 127 - 144. doi:10.1145/128861.128862.
*/
static void euclidianQR(Integer& q, Integer& r, const Integer& x, const Integer& y) {
// compute the floor and then fix the value up if needed.
floorQR(q,r,x,y);
if(r.strictlyNegative()){
// if r < 0
// abs(r) < abs(y)
// - abs(y) < r < 0, then 0 < r + abs(y) < abs(y)
// n = y * q + r
// n = y * q - abs(y) + r + abs(y)
if(r.sgn() >= 0){
// y = abs(y)
// n = y * q - y + r + y
// n = y * (q-1) + (r+y)
q -= 1;
r += y;
}else{
// y = -abs(y)
// n = y * q + y + r - y
// n = y * (q+1) + (r-y)
q += 1;
r -= y;
}
}
}
/**
* Returns the quoitent according to Boute's Euclidean definition.
* See the documentation for euclidianQR.
*/
Integer euclidianDivideQuotient(const Integer& y) const {
Integer q,r;
euclidianQR(q,r, *this, y);
return q;
}
/**
* Returns the remainfing according to Boute's Euclidean definition.
* See the documentation for euclidianQR.
*/
Integer euclidianDivideRemainder(const Integer& y) const {
Integer q,r;
euclidianQR(q,r, *this, y);
return r;
}
/**
* If y divides *this, then exactQuotient returns (this/y)
*/
Integer exactQuotient(const Integer& y) const {
DebugCheckArgument(y.divides(*this), y);
mpz_class q;
mpz_divexact(q.get_mpz_t(), d_value.get_mpz_t(), y.d_value.get_mpz_t());
return Integer( q );
}
/**
* Returns y mod 2^exp
*/
Integer modByPow2(uint32_t exp) const {
mpz_class res;
mpz_fdiv_r_2exp(res.get_mpz_t(), d_value.get_mpz_t(), exp);
return Integer(res);
}
/**
* Returns y / 2^exp
*/
Integer divByPow2(uint32_t exp) const {
mpz_class res;
mpz_fdiv_q_2exp(res.get_mpz_t(), d_value.get_mpz_t(), exp);
return Integer(res);
}
int sgn() const {
return mpz_sgn(d_value.get_mpz_t());
}
inline bool strictlyPositive() const {
return sgn() > 0;
}
inline bool strictlyNegative() const {
return sgn() < 0;
}
inline bool isZero() const {
return sgn() == 0;
}
bool isOne() const {
return mpz_cmp_si(d_value.get_mpz_t(), 1) == 0;
}
bool isNegativeOne() const {
return mpz_cmp_si(d_value.get_mpz_t(), -1) == 0;
}
/**
* Raise this Integer to the power <code>exp</code>.
*
* @param exp the exponent
*/
Integer pow(unsigned long int exp) const {
mpz_class result;
mpz_pow_ui(result.get_mpz_t(),d_value.get_mpz_t(),exp);
return Integer( result );
}
/**
* Return the greatest common divisor of this integer with another.
*/
Integer gcd(const Integer& y) const {
mpz_class result;
mpz_gcd(result.get_mpz_t(), d_value.get_mpz_t(), y.d_value.get_mpz_t());
return Integer(result);
}
/**
* Return the least common multiple of this integer with another.
*/
Integer lcm(const Integer& y) const {
mpz_class result;
mpz_lcm(result.get_mpz_t(), d_value.get_mpz_t(), y.d_value.get_mpz_t());
return Integer(result);
}
/**
* All non-zero integers z, z.divide(0)
* ! zero.divides(zero)
*/
bool divides(const Integer& y) const {
int res = mpz_divisible_p(y.d_value.get_mpz_t(), d_value.get_mpz_t());
return res != 0;
}
/**
* Return the absolute value of this integer.
*/
Integer abs() const {
return d_value >= 0 ? *this : -*this;
}
std::string toString(int base = 10) const{
return d_value.get_str(base);
}
bool fitsSignedInt() const;
bool fitsUnsignedInt() const;
signed int getSignedInt() const;
unsigned int getUnsignedInt() const;
long getLong() const {
long si = d_value.get_si();
// ensure there wasn't overflow
CheckArgument(mpz_cmp_si(d_value.get_mpz_t(), si) == 0, this,
"Overflow detected in Integer::getLong()");
return si;
}
unsigned long getUnsignedLong() const {
unsigned long ui = d_value.get_ui();
// ensure there wasn't overflow
CheckArgument(mpz_cmp_ui(d_value.get_mpz_t(), ui) == 0, this,
"Overflow detected in Integer::getUnsignedLong()");
return ui;
}
/**
* Computes the hash of the node from the first word of the
* numerator, the denominator.
*/
size_t hash() const {
return gmpz_hash(d_value.get_mpz_t());
}
/**
* Returns true iff bit n is set.
*
* @param n the bit to test (0 == least significant bit)
* @return true if bit n is set in this integer; false otherwise
*/
bool testBit(unsigned n) const {
return mpz_tstbit(d_value.get_mpz_t(), n);
}
/**
* Returns k if the integer is equal to 2^(k-1)
* @return k if the integer is equal to 2^(k-1) and 0 otherwise
*/
unsigned isPow2() const {
if (d_value <= 0) return 0;
// check that the number of ones in the binary representation is 1
if (mpz_popcount(d_value.get_mpz_t()) == 1) {
// return the index of the first one plus 1
return mpz_scan1(d_value.get_mpz_t(), 0) + 1;
}
return 0;
}
/**
* If x != 0, returns the smallest n s.t. 2^{n-1} <= abs(x) < 2^{n}.
* If x == 0, returns 1.
*/
size_t length() const {
if(sgn() == 0){
return 1;
}else{
return mpz_sizeinbase(d_value.get_mpz_t(),2);
}
}
static void extendedGcd(Integer& g, Integer& s, Integer& t, const Integer& a, const Integer& b){
//see the documentation for:
//mpz_gcdext (mpz_t g, mpz_t s, mpz_t t, mpz_t a, mpz_t b);
mpz_gcdext (g.d_value.get_mpz_t(), s.d_value.get_mpz_t(), t.d_value.get_mpz_t(), a.d_value.get_mpz_t(), b.d_value.get_mpz_t());
}
/** Returns a reference to the minimum of two integers. */
static const Integer& min(const Integer& a, const Integer& b){
return (a <=b ) ? a : b;
}
/** Returns a reference to the maximum of two integers. */
static const Integer& max(const Integer& a, const Integer& b){
return (a >= b ) ? a : b;
}
friend class CVC4::Rational;
};/* class Integer */
struct IntegerHashFunction {
inline size_t operator()(const CVC4::Integer& i) const {
return i.hash();
}
};/* struct IntegerHashFunction */
inline std::ostream& operator<<(std::ostream& os, const Integer& n) {
return os << n.toString();
}
}/* CVC4 namespace */
#endif /* __CVC4__INTEGER_H */