helper_functions-inl.h

/*
 *  MEGAHIT
 *  Copyright (C) 2014 The University of Hong Kong
 *
 *  This program is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#ifndef HELPER_FUNCTIONS_INL_H_
#define HELPER_FUNCTIONS_INL_H_

#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>

template<typename T1, typename T2>
inline T1 DivCeiling(T1 a, T2 b) {
    return (a + b - 1) / b;
}

inline void debug(const char* format, ...) {
#ifdef DBJ_DEBUG
    va_list args;
    va_start(args, format);
    vfprintf(stdout, format, args);
    va_end(args);
    fflush(stdout);
#endif
}

inline void log(const char* format, ...) {
    va_list args;
    va_start(args, format);
    vfprintf(stdout, format, args);
    va_end(args);
    fflush(stdout);
}

inline void err(const char* format, ...) {
    va_list args;
    va_start(args, format);
    vfprintf(stderr, format, args);
    va_end(args);
    fflush(stderr);
}

inline unsigned int mirror(unsigned int v) {
    // swap odd and even bits
    // v = ((v >> 1) & 0x55555555) | ((v & 0x55555555) << 1);
    // swap consecutive pairs
    v = ((v >> 2) & 0x33333333) | ((v & 0x33333333) << 2);
    // swap nibbles ... 
    v = ((v >> 4) & 0x0F0F0F0F) | ((v & 0x0F0F0F0F) << 4);
    // swap bytes
    v = ((v >> 8) & 0x00FF00FF) | ((v & 0x00FF00FF) << 8);
    // swap 2-byte long pairs
    v = ( v >> 16             ) | ( v               << 16);
    return v;
}


#endif // HELPER_FUNCTIONS_INL_H_