/**
 * random.h: SIMD oriented Fast Mersenne Twister (SFMT) pseudorandom
 *
 * Copyright © 2007 Pippijn van Steenhoven / The Ermyth Team
 * Rights to this code are as documented in COPYING.
 *
 *
 * Portions of this file were derived from sources bearing the following license:
 * Copyright © 2006, 2007 Mutsuo Saito, Makoto Matsumoto and Hiroshima
 * University. All rights reserved.
 * The new BSD License is applied to this software.
 *
 * @author Mutsuo Saito (Hiroshima University)
 * @author Makoto Matsumoto (Hiroshima University)
 *
 * $Id: random.h,v 1.5 2007/09/22 14:27:26 pippijn dead $
 */

#ifndef COMMON_RANDOM_H
#define COMMON_RANDOM_H

#include <stdio.h>

#if defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L)
  #include <inttypes.h>
#elif defined (_MSC_VER) || defined (__BORLANDC__)
  typedef unsigned int uint32_t;
  typedef unsigned __int64 uint64_t;
  #define inline __inline
#else
  #include <inttypes.h>
  #if defined (__GNUC__)
    #define inline __inline__
  #endif
#endif

#ifndef PRIu64
  #if defined (_MSC_VER) || defined (__BORLANDC__)
    #define PRIu64 "I64u"
    #define PRIx64 "I64x"
  #else
    #define PRIu64 "lu"
    #define PRIx64 "lx"
  #endif
#endif

#if defined (__GNUC__)
#define ALWAYSINLINE __attribute__ ((always_inline))
#endif

uint32_t gen_rand32 (void);
uint64_t gen_rand64 (void);
void fill_array32 (uint32_t *array, int size);
void fill_array64 (uint64_t *array, int size);
void init_gen_rand (uint32_t seed);
void init_by_array (uint32_t *init_key, int key_length);
char const * const get_idstring (void);
int get_min_array_size32 (void);
int get_min_array_size64 (void);

/* These real versions are due to Isaku Wada */
/** generates a random number on [0,1]-real-interval */
inline double
to_real1 (uint32_t v)
{
    return v * (1.0/4294967295.0); 
    /* divided by 2^32-1 */ 
}

/** generates a random number on [0,1]-real-interval */
inline double
genrand_real1 (void)
{
    return to_real1 (gen_rand32 ());
}

/** generates a random number on [0,1)-real-interval */
inline double
to_real2 (uint32_t v)
{
    return v * (1.0/4294967296.0); 
    /* divided by 2^32 */
}

/** generates a random number on [0,1)-real-interval */
inline double
genrand_real2 (void)
{
    return to_real2 (gen_rand32 ());
}

/** generates a random number on (0,1)-real-interval */
inline double
to_real3 (uint32_t v)
{
    return ( ((double)v) + 0.5)* (1.0/4294967296.0); 
    /* divided by 2^32 */
}

/** generates a random number on (0,1)-real-interval */
inline double
genrand_real3 (void)
{
    return to_real3 (gen_rand32 ());
}
/** These real versions are due to Isaku Wada */

/** generates a random number on [0,1) with 53-bit resolution*/
inline double
to_res53 (uint64_t v) 
{ 
    return v * (1.0/18446744073709551616.0L);
}

/** generates a random number on [0,1) with 53-bit resolution*/
inline double
genrand_res53 (void) 
{ 
    return to_res53 (gen_rand64 ());
} 

/*------------------------------------------------------
  128-bit SIMD data type for Altivec, SSE2 or standard C
  ------------------------------------------------------*/
#if defined (HAVE_ALTIVEC)
  #if !defined (__APPLE__)
    #include <altivec.h>
  #endif
/** 128-bit data structure */
union W128_T {
    vector unsigned int s;
    uint32_t u[4];
};
/** 128-bit data type */
typedef union W128_T w128_t;

#elif defined (HAVE_SSE2)
  #include <emmintrin.h>

/** 128-bit data structure */
union W128_T {
    __m128i si;
    uint32_t u[4];
};
/** 128-bit data type */
typedef union W128_T w128_t;

#else

/** 128-bit data structure */
struct W128_T {
    uint32_t u[4];
};
/** 128-bit data type */
typedef struct W128_T w128_t;

#endif

#endif