minisat_global.h

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/*****************************************************************************/
/*!
 *\file minisat_global.h
 *\brief MiniSat global functions
 *
 * Author: Alexander Fuchs
 *
 * Created: Fri Sep 08 11:04:00 2006
 *
 * <hr>
 *
 * License to use, copy, modify, sell and/or distribute this software
 * and its documentation for any purpose is hereby granted without
 * royalty, subject to the terms and conditions defined in the \ref
 * LICENSE file provided with this distribution.
 * 
 * <hr>
 */
/*****************************************************************************/

/****************************************************************************************[Global.h]
MiniSat -- Copyright (c) 2003-2005, Niklas Een, Niklas Sorensson

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and
associated documentation files (the "Software"), to deal in the Software without restriction,
including without limitation the rights to use, copy, modify, merge, publish, distribute,
sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or
substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT
NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT
OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
**************************************************************************************************/

#ifndef _cvc3__minisat__global_h_
#define _cvc3__minisat__global_h_

//=================================================================================================
// Basic Types & Minor Things:
// provides lbool and vec

#include "debug.h"
#include <cstdio>
#include <cstdlib>
#include <climits>
#include <cfloat>
#include <cstring>
#include <new>


namespace MiniSat {

template<class T> static inline T min(T x, T y) { return (x < y) ? x : y; }
template<class T> static inline T max(T x, T y) { return (x > y) ? x : y; }

template <bool> struct STATIC_ASSERTION_FAILURE;
template <> struct STATIC_ASSERTION_FAILURE<true>{};
#define TEMPLATE_FAIL STATIC_ASSERTION_FAILURE<false>()


//=================================================================================================
// 'malloc()'-style memory allocation -- never returns NULL; aborts instead:


template<class T> static inline T* xmalloc(size_t size) {
    T*   tmp = (T*)malloc(size * sizeof(T));
    DebugAssert(size == 0 || tmp != NULL, "Minisat::Global::xmalloc");
    return tmp; }

template<class T> static inline T* xrealloc(T* ptr, size_t size) {
    T*   tmp = (T*)realloc((void*)ptr, size * sizeof(T));
    DebugAssert(size == 0 || tmp != NULL, "Minisat::Global::xrealloc");
    return tmp; }

template<class T> static inline void xfree(T *ptr) {
    if (ptr != NULL) free((void*)ptr); }


//=================================================================================================
// Random numbers:


// Returns a random float 0 <= x < 1. Seed must never be 0.
static inline double drand(double& seed) {
    seed *= 1389796;
    int q = (int)(seed / 2147483647);
    seed -= (double)q * 2147483647;
    return seed / 2147483647; }

// Returns a random integer 0 <= x < size. Seed must never be 0.
static inline int irand(double& seed, int size) {
    return (int)(drand(seed) * size); }



//=================================================================================================
// 'vec' -- automatically resizable arrays (via 'push()' method):


// NOTE! Don't use this vector on datatypes that cannot be re-located in memory (with realloc)

template<class T>
class vec {
    T*  data;
    int sz;
    int cap;

    void     init(int size, const T& pad);
    void     grow(int min_cap);

public:
    // Types:
    typedef int Key;
    typedef T   Datum;

    // Constructors:
    vec(void)                   : data(NULL) , sz(0)   , cap(0)    { }
    vec(int size)               : data(NULL) , sz(0)   , cap(0)    { growTo(size); }
    vec(int size, const T& pad) : data(NULL) , sz(0)   , cap(0)    { growTo(size, pad); }
    vec(T* array, int size)     : data(array), sz(size), cap(size) { }      // (takes ownership of array -- will be deallocated with 'xfree()')
   ~vec(void)                                                      { clear(true); }

    // Ownership of underlying array:
    T*       release  (void)           { T* ret = data; data = NULL; sz = 0; cap = 0; return ret; }
    operator T*       (void)           { return data; }     // (unsafe but convenient)
    operator const T* (void) const     { return data; }

    // Size operations:
    int      size   (void) const       { return sz; }
    void     shrink (int nelems)       { DebugAssert(nelems <= sz, "MiniSat::vec::shrink");
                                         for (int i = 0; i < nelems; i++) sz--, data[sz].~T(); }
    void     pop    (void)             { sz--, data[sz].~T(); }
    void     growTo (int size);
    void     growTo (int size, const T& pad);
    void     clear  (bool dealloc = false);
    void     capacity (int size) { grow(size); }

    // Stack interface:
    void     push  (void)              { if (sz == cap) grow(sz+1); new (&data[sz]) T()    ; sz++; }
    void     push  (const T& elem)     { if (sz == cap) grow(sz+1); new (&data[sz]) T(elem); sz++; }
    const T& last  (void) const        { return data[sz-1]; }
    T&       last  (void)              { return data[sz-1]; }

    // Vector interface:
    const T& operator [] (int index) const  { return data[index]; }
    T&       operator [] (int index)        { return data[index]; }

    // Don't allow copying (error prone):
    vec<T>&  operator = (vec<T>& other) { TEMPLATE_FAIL; }
             vec        (vec<T>& other) { TEMPLATE_FAIL; }

    // Duplicatation (preferred instead):
    void copyTo(vec<T>& copy) const { copy.clear(); copy.growTo(sz); for (int i = 0; i < sz; i++) new (&copy[i]) T(data[i]); }
    void moveTo(vec<T>& dest) { dest.clear(true); dest.data = data; dest.sz = sz; dest.cap = cap; data = NULL; sz = 0; cap = 0; }
};

template<class T>
void vec<T>::grow(int min_cap) {
    if (min_cap <= cap) return;
    if (cap == 0) cap = (min_cap >= 2) ? min_cap : 2;
    else          do cap = (cap*3+1) >> 1; while (cap < min_cap);
    data = xrealloc(data, cap); }

template<class T>
void vec<T>::growTo(int size, const T& pad) {
    if (sz >= size) return;
    grow(size);
    for (int i = sz; i < size; i++) new (&data[i]) T(pad);
    sz = size; }

template<class T>
void vec<T>::growTo(int size) {
    if (sz >= size) return;
    grow(size);
    for (int i = sz; i < size; i++) new (&data[i]) T();
    sz = size; }

template<class T>
void vec<T>::clear(bool dealloc) {
    if (data != NULL){
        for (int i = 0; i < sz; i++) data[i].~T();
        sz = 0;
        if (dealloc) xfree(data), data = NULL, cap = 0; } }


//=================================================================================================
// Lifted booleans:


class lbool {
    int     value;
    explicit lbool(int v) : value(v) { }

public:
    lbool()       : value(0) { }
    lbool(bool x) : value((int)x*2-1) { }
    int toInt(void) const { return value; }

    bool  operator == (const lbool& other) const { return value == other.value; }
    bool  operator != (const lbool& other) const { return value != other.value; }
    lbool operator ~  (void)               const { return lbool(-value); }

    friend int   toInt  (lbool l);
    friend lbool toLbool(int   v);
};
inline int   toInt  (lbool l) { return l.toInt(); }
inline lbool toLbool(int   v) { return lbool(v);  }

const lbool l_True  = toLbool( 1);
const lbool l_False = toLbool(-1);
const lbool l_Undef = toLbool( 0);


//=================================================================================================
// Relation operators -- extend definitions from '==' and '<'


#ifndef __SGI_STL_INTERNAL_RELOPS   // (be aware of SGI's STL implementation...)
#define __SGI_STL_INTERNAL_RELOPS
template <class T> static inline bool operator != (const T& x, const T& y) { return !(x == y); }
template <class T> static inline bool operator >  (const T& x, const T& y) { return y < x;     }
template <class T> static inline bool operator <= (const T& x, const T& y) { return !(y < x);  }
template <class T> static inline bool operator >= (const T& x, const T& y) { return !(x < y);  }
#endif

}

//=================================================================================================
#endif