#pragma once

/**

 * @file  SFMT-sse2.h

 * @brief SIMD oriented Fast Mersenne Twister(SFMT) for Intel SSE2

 *

 * @author Mutsuo Saito (Hiroshima University)

 * @author Makoto Matsumoto (Hiroshima University)

 *

 * @note We assume LITTLE ENDIAN in this file

 *

 * Copyright (C) 2006, 2007 Mutsuo Saito, Makoto Matsumoto and Hiroshima

 * University. All rights reserved.

 *

 * The new BSD License is applied to this software, see LICENSE.txt

 */

#ifndef SFMT_SSE2_H

#define SFMT_SSE2_H

inline static void mm_recursion(__m128i * r, __m128i a, __m128i b,

        __m128i c, __m128i d);

/**

 * This function represents the recursion formula.

 * @param r an output

 * @param a a 128-bit part of the interal state array

 * @param b a 128-bit part of the interal state array

 * @param c a 128-bit part of the interal state array

 * @param d a 128-bit part of the interal state array

 */

inline static void mm_recursion(__m128i * r, __m128i a, __m128i b,

        __m128i c, __m128i d)

{

    __m128i v, x, y, z;

    y = _mm_srli_epi32(b, SFMT_SR1);

    z = _mm_srli_si128(c, SFMT_SR2);

    v = _mm_slli_epi32(d, SFMT_SL1);

    z = _mm_xor_si128(z, a);

    z = _mm_xor_si128(z, v);

    x = _mm_slli_si128(a, SFMT_SL2);

    y = _mm_and_si128(y, sse2_param_mask.si);

    z = _mm_xor_si128(z, x);

    z = _mm_xor_si128(z, y);

    *r = z;

}

/**

 * This function fills the internal state array with pseudorandom

 * integers.

 * @param sfmt SFMT internal state

 */

void sfmt_gen_rand_all(sfmt_t * sfmt) {

    int i;

    __m128i r1, r2;

    w128_t * pstate = sfmt->state;

    r1 = pstate[SFMT_N - 2].si;

    r2 = pstate[SFMT_N - 1].si;

    for (i = 0; i < SFMT_N - SFMT_POS1; 
i++5.10M
) {

  mm_recursion(&pstate[i].si, pstate[i].si,

         pstate[i + SFMT_POS1].si, r1, r2);

  r1 = r2;

  r2 = pstate[i].si;

    }

    for (; i < SFMT_N; 
i++18.3M
) {

  mm_recursion(&pstate[i].si, pstate[i].si,

         pstate[i + SFMT_POS1 - SFMT_N].si,

         r1, r2);

  r1 = r2;

  r2 = pstate[i].si;

    }

}

/**

 * This function fills the user-specified array with pseudorandom

 * integers.

 * @param sfmt SFMT internal state.

 * @param array an 128-bit array to be filled by pseudorandom numbers.

 * @param size number of 128-bit pseudorandom numbers to be generated.

 */

static void gen_rand_array(sfmt_t * sfmt, w128_t * array, int size)

{

    int i, j;

    __m128i r1, r2;

    w128_t * pstate = sfmt->state;

    r1 = pstate[SFMT_N - 2].si;

    r2 = pstate[SFMT_N - 1].si;

    for (i = 0; i < SFMT_N - SFMT_POS1; i++) {

  mm_recursion(&array[i].si, pstate[i].si,

         pstate[i + SFMT_POS1].si, r1, r2);

  r1 = r2;

  r2 = array[i].si;

    }

    for (; i < SFMT_N; i++) {

  mm_recursion(&array[i].si, pstate[i].si,

         array[i + SFMT_POS1 - SFMT_N].si, r1, r2);

  r1 = r2;

  r2 = array[i].si;

    }

    for (; i < size - SFMT_N; i++) {

  mm_recursion(&array[i].si, array[i - SFMT_N].si,

         array[i + SFMT_POS1 - SFMT_N].si, r1, r2);

  r1 = r2;

  r2 = array[i].si;

    }

    for (j = 0; j < 2 * SFMT_N - size; j++) {

  pstate[j] = array[j + size - SFMT_N];

    }

    for (; i < size; i++, j++) {

  mm_recursion(&array[i].si, array[i - SFMT_N].si,

         array[i + SFMT_POS1 - SFMT_N].si, r1, r2);

  r1 = r2;

  r2 = array[i].si;

  pstate[j] = array[i];

    }

}

#endif