/* This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifdef SOLARIS

#define RF_INLINE_MACROS 1

#endif

static const double TwoTo16 = 65536.0;

static const double TwoToMinus16 = 1.0 / 65536.0;

static const double Zero = 0.0;

static const double TwoTo32 = 65536.0 * 65536.0;

static const double TwoToMinus32 = 1.0 / (65536.0 * 65536.0);

#ifdef RF_INLINE_MACROS

double upper32(double);

double lower32(double, double);

double mod(double, double, double);

void i16_to_d16_and_d32x4(const double * /*1/(2^16)*/,

                          const double * /* 2^16*/,

                          const double * /* 0 */,

                          double * /*result16*/,

                          double * /* result32 */,

                          float * /*source - should be unsigned int* converted to float* */);

#else

#ifdef MP_USE_FLOOR

#include <math.h>

#else

#define floor(d) ((double)((unsigned long long)(d)))

#endif

static double

upper32(double x)

{

    return floor(x * TwoToMinus32);

}

static double

lower32(double x, double y)

{

    return x - TwoTo32 * floor(x * TwoToMinus32);

}

static double

mod(double x, double oneoverm, double m)

{

    return x - m * floor(x * oneoverm);

}

#endif

static void

cleanup(double *dt, int from, int tlen)

{

    int i;

    double tmp, tmp1, x, x1;

    tmp = tmp1 = Zero;

    /* original code **

     for(i=2*from;i<2*tlen-2;i++)

       {

         x=dt[i];

         dt[i]=lower32(x,Zero)+tmp1;

         tmp1=tmp;

         tmp=upper32(x);

       }

     dt[tlen-2]+=tmp1;

     dt[tlen-1]+=tmp;

     **end original code ***/

    /* new code ***/

    for (i = 2 * from; i < 2 * tlen; i += 2) {

        x = dt[i];

        x1 = dt[i + 1];

        dt[i] = lower32(x, Zero) + tmp;

        dt[i + 1] = lower32(x1, Zero) + tmp1;

        tmp = upper32(x);

        tmp1 = upper32(x1);

    }

    /** end new code **/

}

void

conv_d16_to_i32(unsigned int *i32, double *d16, long long *tmp, int ilen)

{

    int i;

    long long t, t1, a, b, c, d;

    t1 = 0;

    a = (long long)d16[0];

    b = (long long)d16[1];

    for (i = 0; i < ilen - 1; i++) {

        c = (long long)d16[2 * i + 2];

        t1 += (unsigned int)a;

        t = (a >> 32);

        d = (long long)d16[2 * i + 3];

        t1 += (b & 0xffff) << 16;

        t += (b >> 16) + (t1 >> 32);

        i32[i] = (unsigned int)t1;

        t1 = t;

        a = c;

        b = d;

    }

    t1 += (unsigned int)a;

    t = (a >> 32);

    t1 += (b & 0xffff) << 16;

    i32[i] = (unsigned int)t1;

}

void

conv_i32_to_d32(double *d32, unsigned int *i32, int len)

{

    int i;

#pragma pipeloop(0)

    for (i = 0; i < len; i++)

        d32[i] = (double)(i32[i]);

}

void

conv_i32_to_d16(double *d16, unsigned int *i32, int len)

{

    int i;

    unsigned int a;

#pragma pipeloop(0)

    for (i = 0; i < len; i++) {

        a = i32[i];

        d16[2 * i] = (double)(a & 0xffff);

        d16[2 * i + 1] = (double)(a >> 16);

    }

}

void

conv_i32_to_d32_and_d16(double *d32, double *d16,

                        unsigned int *i32, int len)

{

    int i = 0;

    unsigned int a;

#pragma pipeloop(0)

#ifdef RF_INLINE_MACROS

    for (; i < len - 3; i += 4) {

        i16_to_d16_and_d32x4(&TwoToMinus16, &TwoTo16, &Zero,

                             &(d16[2 * i]), &(d32[i]), (float *)(&(i32[i])));

    }

#endif

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

        a = i32[i];

        d32[i] = (double)(i32[i]);

        d16[2 * i] = (double)(a & 0xffff);

        d16[2 * i + 1] = (double)(a >> 16);

    }

}

void

adjust_montf_result(unsigned int *i32, unsigned int *nint, int len)

{

    long long acc;

    int i;

    if (i32[len] > 0)

        i = -1;

    else {

        for (i = len - 1; i >= 0; i--) {

            if (i32[i] != nint[i])

                break;

        }

    }

    if ((i < 0) || (i32[i] > nint[i])) {

        acc = 0;

        for (i = 0; i < len; i++) {

            acc = acc + (unsigned long long)(i32[i]) - (unsigned long long)(nint[i]);

            i32[i] = (unsigned int)acc;

            acc = acc >> 32;

        }

    }

}

/*

** the lengths of the input arrays should be at least the following:

** result[nlen+1], dm1[nlen], dm2[2*nlen+1], dt[4*nlen+2], dn[nlen], nint[nlen]

** all of them should be different from one another

**

*/

void

mont_mulf_noconv(unsigned int *result,

                 double *dm1, double *dm2, double *dt,

                 double *dn, unsigned int *nint,

                 int nlen, double dn0)

{

    int i, j, jj;

    int tmp;

    double digit, m2j, nextm2j, a, b;

    double *dptmp, *pdm1, *pdm2, *pdn, *pdtj, pdn_0, pdm1_0;

    pdm1 = &(dm1[0]);

    pdm2 = &(dm2[0]);

    pdn = &(dn[0]);

    pdm2[2 * nlen] = Zero;

    if (nlen != 16) {

        for (i = 0; i < 4 * nlen + 2; i++)

            dt[i] = Zero;

        a = dt[0] = pdm1[0] * pdm2[0];

        digit = mod(lower32(a, Zero) * dn0, TwoToMinus16, TwoTo16);

        pdtj = &(dt[0]);

        for (j = jj = 0; j < 2 * nlen; j++, jj++, pdtj++) {

            m2j = pdm2[j];

            a = pdtj[0] + pdn[0] * digit;

            b = pdtj[1] + pdm1[0] * pdm2[j + 1] + a * TwoToMinus16;

            pdtj[1] = b;

#pragma pipeloop(0)

            for (i = 1; i < nlen; i++) {

                pdtj[2 * i] += pdm1[i] * m2j + pdn[i] * digit;

            }

            if ((jj == 30)) {

                cleanup(dt, j / 2 + 1, 2 * nlen + 1);

                jj = 0;

            }

            digit = mod(lower32(b, Zero) * dn0, TwoToMinus16, TwoTo16);

        }

    } else {

        a = dt[0] = pdm1[0] * pdm2[0];

        dt[65] = dt[64] = dt[63] = dt[62] = dt[61] = dt[60] =

            dt[59] = dt[58] = dt[57] = dt[56] = dt[55] = dt[54] =

                dt[53] = dt[52] = dt[51] = dt[50] = dt[49] = dt[48] =

                    dt[47] = dt[46] = dt[45] = dt[44] = dt[43] = dt[42] =

                        dt[41] = dt[40] = dt[39] = dt[38] = dt[37] = dt[36] =

                            dt[35] = dt[34] = dt[33] = dt[32] = dt[31] = dt[30] =

                                dt[29] = dt[28] = dt[27] = dt[26] = dt[25] = dt[24] =

                                    dt[23] = dt[22] = dt[21] = dt[20] = dt[19] = dt[18] =

                                        dt[17] = dt[16] = dt[15] = dt[14] = dt[13] = dt[12] =

                                            dt[11] = dt[10] = dt[9] = dt[8] = dt[7] = dt[6] =

                                                dt[5] = dt[4] = dt[3] = dt[2] = dt[1] = Zero;

        pdn_0 = pdn[0];

        pdm1_0 = pdm1[0];

        digit = mod(lower32(a, Zero) * dn0, TwoToMinus16, TwoTo16);

        pdtj = &(dt[0]);

        for (j = 0; j < 32; j++, pdtj++) {

            m2j = pdm2[j];

            a = pdtj[0] + pdn_0 * digit;

            b = pdtj[1] + pdm1_0 * pdm2[j + 1] + a * TwoToMinus16;

            pdtj[1] = b;

            /**** this loop will be fully unrolled:

             for(i=1;i<16;i++)

               {

                 pdtj[2*i]+=pdm1[i]*m2j+pdn[i]*digit;

               }

             *************************************/

            pdtj[2] += pdm1[1] * m2j + pdn[1] * digit;

            pdtj[4] += pdm1[2] * m2j + pdn[2] * digit;

            pdtj[6] += pdm1[3] * m2j + pdn[3] * digit;

            pdtj[8] += pdm1[4] * m2j + pdn[4] * digit;

            pdtj[10] += pdm1[5] * m2j + pdn[5] * digit;

            pdtj[12] += pdm1[6] * m2j + pdn[6] * digit;

            pdtj[14] += pdm1[7] * m2j + pdn[7] * digit;

            pdtj[16] += pdm1[8] * m2j + pdn[8] * digit;

            pdtj[18] += pdm1[9] * m2j + pdn[9] * digit;

            pdtj[20] += pdm1[10] * m2j + pdn[10] * digit;

            pdtj[22] += pdm1[11] * m2j + pdn[11] * digit;

            pdtj[24] += pdm1[12] * m2j + pdn[12] * digit;

            pdtj[26] += pdm1[13] * m2j + pdn[13] * digit;

            pdtj[28] += pdm1[14] * m2j + pdn[14] * digit;

            pdtj[30] += pdm1[15] * m2j + pdn[15] * digit;

            /* no need for cleenup, cannot overflow */

            digit = mod(lower32(b, Zero) * dn0, TwoToMinus16, TwoTo16);

        }

    }

    conv_d16_to_i32(result, dt + 2 * nlen, (long long *)dt, nlen + 1);

    adjust_montf_result(result, nint, nlen);

}