/*

 * Copyright 2002-2025 The OpenSSL Project Authors. All Rights Reserved.

 *

 * Licensed under the Apache License 2.0 (the "License").  You may not use

 * this file except in compliance with the License.  You can obtain a copy

 * in the file LICENSE in the source distribution or at

 * https://www.openssl.org/source/license.html

 */

#include "../bn_local.h"

#if !(defined(__GNUC__) && __GNUC__ >= 2)

/* clang-format off */

# include "../bn_asm.c"         /* kind of dirty hack for Sun Studio */

/* clang-format on */

#else

/*-

 * x86_64 BIGNUM accelerator version 0.1, December 2002.

 *

 * Implemented by Andy Polyakov <https://github.com/dot-asm> for the OpenSSL

 * project.

 *

 * Rights for redistribution and usage in source and binary forms are

 * granted according to the License. Warranty of any kind is disclaimed.

 *

 * Q. Version 0.1? It doesn't sound like Andy, he used to assign real

 *    versions, like 1.0...

 * A. Well, that's because this code is basically a quick-n-dirty

 *    proof-of-concept hack. As you can see it's implemented with

 *    inline assembler, which means that you're bound to GCC and that

 *    there might be enough room for further improvement.

 *

 * Q. Why inline assembler?

 * A. x86_64 features own ABI which I'm not familiar with. This is

 *    why I decided to let the compiler take care of subroutine

 *    prologue/epilogue as well as register allocation. For reference.

 *    Win64 implements different ABI for AMD64, different from Linux.

 *

 * Q. How much faster does it get?

 * A. 'apps/openssl speed rsa dsa' output with no-asm:

 *

 *                        sign    verify    sign/s verify/s

 *      rsa  512 bits   0.0006s   0.0001s   1683.8  18456.2

 *      rsa 1024 bits   0.0028s   0.0002s    356.0   6407.0

 *      rsa 2048 bits   0.0172s   0.0005s     58.0   1957.8

 *      rsa 4096 bits   0.1155s   0.0018s      8.7    555.6

 *                        sign    verify    sign/s verify/s

 *      dsa  512 bits   0.0005s   0.0006s   2100.8   1768.3

 *      dsa 1024 bits   0.0014s   0.0018s    692.3    559.2

 *      dsa 2048 bits   0.0049s   0.0061s    204.7    165.0

 *

 *    'apps/openssl speed rsa dsa' output with this module:

 *

 *                        sign    verify    sign/s verify/s

 *      rsa  512 bits   0.0004s   0.0000s   2767.1  33297.9

 *      rsa 1024 bits   0.0012s   0.0001s    867.4  14674.7

 *      rsa 2048 bits   0.0061s   0.0002s    164.0   5270.0

 *      rsa 4096 bits   0.0384s   0.0006s     26.1   1650.8

 *                        sign    verify    sign/s verify/s

 *      dsa  512 bits   0.0002s   0.0003s   4442.2   3786.3

 *      dsa 1024 bits   0.0005s   0.0007s   1835.1   1497.4

 *      dsa 2048 bits   0.0016s   0.0020s    620.4    504.6

 *

 *    For the reference. IA-32 assembler implementation performs

 *    very much like 64-bit code compiled with no-asm on the same

 *    machine.

 */

#undef mul

#undef mul_add

/*-

 * "m"(a), "+m"(r)      is the way to favor DirectPath µ-code;

 * "g"(0)               let the compiler to decide where does it

 *                      want to keep the value of zero;

 */

#define mul_add(r, a, word, carry)    \

    do {                              \

        register BN_ULONG high, low;  \

        asm("mulq %3"                 \

            : "=a"(low), "=d"(high)   \

            : "a"(word), "m"(a)       \

            : "cc");                  \

        asm("addq %2,%0; adcq %3,%1"  \

            : "+r"(carry), "+d"(high) \

            : "a"(low), "g"(0)        \

            : "cc");                  \

        asm("addq %2,%0; adcq %3,%1"  \

            : "+m"(r), "+d"(high)     \

            : "r"(carry), "g"(0)      \

            : "cc");                  \

        carry = high;                 \

    } while (0)

#define mul(r, a, word, carry)        \

    do {                              \

        register BN_ULONG high, low;  \

        asm("mulq %3"                 \

            : "=a"(low), "=d"(high)   \

            : "a"(word), "g"(a)       \

            : "cc");                  \

        asm("addq %2,%0; adcq %3,%1"  \

            : "+r"(carry), "+d"(high) \

            : "a"(low), "g"(0)        \

            : "cc");                  \

        (r) = carry, carry = high;    \

    } while (0)

#undef sqr

#define sqr(r0, r1, a)       \

    asm("mulq %2"            \

        : "=a"(r0), "=d"(r1) \

        : "a"(a)             \

        : "cc");

BN_ULONG bn_mul_add_words(BN_ULONG *rp, const BN_ULONG *ap, int num,

    BN_ULONG w)

{

    BN_ULONG c1 = 0;

    if (num <= 0)

        return c1;

    while (num & ~3) {

        mul_add(rp[0], ap[0], w, c1);

        mul_add(rp[1], ap[1], w, c1);

        mul_add(rp[2], ap[2], w, c1);

        mul_add(rp[3], ap[3], w, c1);

        ap += 4;

        rp += 4;

        num -= 4;

    }

    if (num) {

        mul_add(rp[0], ap[0], w, c1);

        if (--num == 0)

            return c1;

        mul_add(rp[1], ap[1], w, c1);

        if (--num == 0)

            return c1;

        mul_add(rp[2], ap[2], w, c1);

        return c1;

    }

    return c1;

}

BN_ULONG bn_mul_words(BN_ULONG *rp, const BN_ULONG *ap, int num, BN_ULONG w)

{

    BN_ULONG c1 = 0;

    if (num <= 0)

        return c1;

    while (num & ~3) {

        mul(rp[0], ap[0], w, c1);

        mul(rp[1], ap[1], w, c1);

        mul(rp[2], ap[2], w, c1);

        mul(rp[3], ap[3], w, c1);

        ap += 4;

        rp += 4;

        num -= 4;

    }

    if (num) {

        mul(rp[0], ap[0], w, c1);

        if (--num == 0)

            return c1;

        mul(rp[1], ap[1], w, c1);

        if (--num == 0)

            return c1;

        mul(rp[2], ap[2], w, c1);

    }

    return c1;

}

void bn_sqr_words(BN_ULONG *r, const BN_ULONG *a, int n)

{

    if (n <= 0)

        return;

    while (n & ~3) {

        sqr(r[0], r[1], a[0]);

        sqr(r[2], r[3], a[1]);

        sqr(r[4], r[5], a[2]);

        sqr(r[6], r[7], a[3]);

        a += 4;

        r += 8;

        n -= 4;

    }

    if (n) {

        sqr(r[0], r[1], a[0]);

        if (--n == 0)

            return;

        sqr(r[2], r[3], a[1]);

        if (--n == 0)

            return;

        sqr(r[4], r[5], a[2]);

    }

}

BN_ULONG bn_div_words(BN_ULONG h, BN_ULONG l, BN_ULONG d)

{

    BN_ULONG ret, waste;

    asm("divq      %4" : "=a"(ret), "=d"(waste)

        : "a"(l), "d"(h), "r"(d)

        : "cc");

    return ret;

}

BN_ULONG bn_add_words(BN_ULONG *rp, const BN_ULONG *ap, const BN_ULONG *bp,

    int n)

{

    BN_ULONG ret;

    size_t i = 0;

    if (n <= 0)

        return 0;

    asm volatile("       subq    %0,%0           \n" /* clear carry */

                 "       jmp     1f              \n"

                 ".p2align 4                     \n"

                 "1:     movq    (%4,%2,8),%0    \n"

                 "       adcq    (%5,%2,8),%0    \n"

                 "       movq    %0,(%3,%2,8)    \n"

                 "       lea     1(%2),%2        \n"

                 "       dec     %1              \n"

                 "       jnz     1b              \n"

                 "       sbbq    %0,%0           \n"

        : "=&r"(ret), "+c"(n), "+r"(i)

        : "r"(rp), "r"(ap), "r"(bp)

        : "cc", "memory");

    return ret & 1;

}

#ifndef SIMICS

BN_ULONG bn_sub_words(BN_ULONG *rp, const BN_ULONG *ap, const BN_ULONG *bp,

    int n)

{

    BN_ULONG ret;

    size_t i = 0;

    if (n <= 0)

        return 0;

    asm volatile("       subq    %0,%0           \n" /* clear borrow */

                 "       jmp     1f              \n"

                 ".p2align 4                     \n"

                 "1:     movq    (%4,%2,8),%0    \n"

                 "       sbbq    (%5,%2,8),%0    \n"

                 "       movq    %0,(%3,%2,8)    \n"

                 "       lea     1(%2),%2        \n"

                 "       dec     %1              \n"

                 "       jnz     1b              \n"

                 "       sbbq    %0,%0           \n"

        : "=&r"(ret), "+c"(n), "+r"(i)

        : "r"(rp), "r"(ap), "r"(bp)

        : "cc", "memory");

    return ret & 1;

}

#else

/* Simics 1.4<7 has buggy sbbq:-( */

#define BN_MASK2 0xffffffffffffffffL

BN_ULONG bn_sub_words(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, int n)

{

    BN_ULONG t1, t2;

    int c = 0;

    if (n <= 0)

        return (BN_ULONG)0;

    for (;;) {

        t1 = a[0];

        t2 = b[0];

        r[0] = (t1 - t2 - c) & BN_MASK2;

        if (t1 != t2)

            c = (t1 < t2);

        if (--n <= 0)

            break;

        t1 = a[1];

        t2 = b[1];

        r[1] = (t1 - t2 - c) & BN_MASK2;

        if (t1 != t2)

            c = (t1 < t2);

        if (--n <= 0)

            break;

        t1 = a[2];

        t2 = b[2];

        r[2] = (t1 - t2 - c) & BN_MASK2;

        if (t1 != t2)

            c = (t1 < t2);

        if (--n <= 0)

            break;

        t1 = a[3];

        t2 = b[3];

        r[3] = (t1 - t2 - c) & BN_MASK2;

        if (t1 != t2)

            c = (t1 < t2);

        if (--n <= 0)

            break;

        a += 4;

        b += 4;

        r += 4;

    }

    return c;

}

#endif

/* mul_add_c(a,b,c0,c1,c2)  -- c+=a*b for three word number c=(c2,c1,c0) */

/* mul_add_c2(a,b,c0,c1,c2) -- c+=2*a*b for three word number c=(c2,c1,c0) */

/* sqr_add_c(a,i,c0,c1,c2)  -- c+=a[i]^2 for three word number c=(c2,c1,c0) */

/*

 * sqr_add_c2(a,i,c0,c1,c2) -- c+=2*a[i]*a[j] for three word number

 * c=(c2,c1,c0)

 */

/*

 * Keep in mind that carrying into high part of multiplication result

 * can not overflow, because it cannot be all-ones.

 */

#if 0

/* original macros are kept for reference purposes */

#define mul_add_c(a, b, c0, c1, c2)    \

    do {                               \

        BN_ULONG ta = (a), tb = (b);   \

        BN_ULONG lo, hi;               \

        BN_UMULT_LOHI(lo, hi, ta, tb); \

        c0 += lo;                      \

        hi += (c0 < lo) ? 1 : 0;       \

        c1 += hi;                      \

        c2 += (c1 < hi) ? 1 : 0;       \

    } while (0)

#define mul_add_c2(a, b, c0, c1, c2)   \

    do {                               \

        BN_ULONG ta = (a), tb = (b);   \

        BN_ULONG lo, hi, tt;           \

        BN_UMULT_LOHI(lo, hi, ta, tb); \

        c0 += lo;                      \

        tt = hi + ((c0 < lo) ? 1 : 0); \

        c1 += tt;                      \

        c2 += (c1 < tt) ? 1 : 0;       \

        c0 += lo;                      \

        hi += (c0 < lo) ? 1 : 0;       \

        c1 += hi;                      \

        c2 += (c1 < hi) ? 1 : 0;       \

    } while (0)

#define sqr_add_c(a, i, c0, c1, c2)    \

    do {                               \

        BN_ULONG ta = (a)[i];          \

        BN_ULONG lo, hi;               \

        BN_UMULT_LOHI(lo, hi, ta, ta); \

        c0 += lo;                      \

        hi += (c0 < lo) ? 1 : 0;       \

        c1 += hi;                      \

        c2 += (c1 < hi) ? 1 : 0;       \

    } while (0)

#else

#define mul_add_c(a, b, c0, c1, c2)              \

    do {                                         \

        BN_ULONG t1, t2;                         \

        asm("mulq %3"                            \

            : "=a"(t1), "=d"(t2)                 \

            : "a"(a), "m"(b)                     \

            : "cc");                             \

        asm("addq %3,%0; adcq %4,%1; adcq %5,%2" \

            : "+r"(c0), "+r"(c1), "+r"(c2)       \

            : "r"(t1), "r"(t2), "g"(0)           \

            : "cc");                             \

    } while (0)

#define sqr_add_c(a, i, c0, c1, c2)              \

    do {                                         \

        BN_ULONG t1, t2;                         \

        asm("mulq %2"                            \

            : "=a"(t1), "=d"(t2)                 \

            : "a"(a[i])                          \

            : "cc");                             \

        asm("addq %3,%0; adcq %4,%1; adcq %5,%2" \

            : "+r"(c0), "+r"(c1), "+r"(c2)       \

            : "r"(t1), "r"(t2), "g"(0)           \

            : "cc");                             \

    } while (0)

#define mul_add_c2(a, b, c0, c1, c2)             \

    do {                                         \

        BN_ULONG t1, t2;                         \

        asm("mulq %3"                            \

            : "=a"(t1), "=d"(t2)                 \

            : "a"(a), "m"(b)                     \

            : "cc");                             \

        asm("addq %3,%0; adcq %4,%1; adcq %5,%2" \

            : "+r"(c0), "+r"(c1), "+r"(c2)       \

            : "r"(t1), "r"(t2), "g"(0)           \

            : "cc");                             \

        asm("addq %3,%0; adcq %4,%1; adcq %5,%2" \

            : "+r"(c0), "+r"(c1), "+r"(c2)       \

            : "r"(t1), "r"(t2), "g"(0)           \

            : "cc");                             \

    } while (0)

#endif

#define sqr_add_c2(a, i, j, c0, c1, c2) \

    mul_add_c2((a)[i], (a)[j], c0, c1, c2)

void bn_mul_comba8(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b)

{

    BN_ULONG c1, c2, c3;

    c1 = 0;

    c2 = 0;

    c3 = 0;

    mul_add_c(a[0], b[0], c1, c2, c3);

    r[0] = c1;

    c1 = 0;

    mul_add_c(a[0], b[1], c2, c3, c1);

    mul_add_c(a[1], b[0], c2, c3, c1);

    r[1] = c2;

    c2 = 0;

    mul_add_c(a[2], b[0], c3, c1, c2);

    mul_add_c(a[1], b[1], c3, c1, c2);

    mul_add_c(a[0], b[2], c3, c1, c2);

    r[2] = c3;

    c3 = 0;

    mul_add_c(a[0], b[3], c1, c2, c3);

    mul_add_c(a[1], b[2], c1, c2, c3);

    mul_add_c(a[2], b[1], c1, c2, c3);

    mul_add_c(a[3], b[0], c1, c2, c3);

    r[3] = c1;

    c1 = 0;

    mul_add_c(a[4], b[0], c2, c3, c1);

    mul_add_c(a[3], b[1], c2, c3, c1);

    mul_add_c(a[2], b[2], c2, c3, c1);

    mul_add_c(a[1], b[3], c2, c3, c1);

    mul_add_c(a[0], b[4], c2, c3, c1);

    r[4] = c2;

    c2 = 0;

    mul_add_c(a[0], b[5], c3, c1, c2);

    mul_add_c(a[1], b[4], c3, c1, c2);

    mul_add_c(a[2], b[3], c3, c1, c2);

    mul_add_c(a[3], b[2], c3, c1, c2);

    mul_add_c(a[4], b[1], c3, c1, c2);

    mul_add_c(a[5], b[0], c3, c1, c2);

    r[5] = c3;

    c3 = 0;

    mul_add_c(a[6], b[0], c1, c2, c3);

    mul_add_c(a[5], b[1], c1, c2, c3);

    mul_add_c(a[4], b[2], c1, c2, c3);

    mul_add_c(a[3], b[3], c1, c2, c3);

    mul_add_c(a[2], b[4], c1, c2, c3);

    mul_add_c(a[1], b[5], c1, c2, c3);

    mul_add_c(a[0], b[6], c1, c2, c3);

    r[6] = c1;

    c1 = 0;

    mul_add_c(a[0], b[7], c2, c3, c1);

    mul_add_c(a[1], b[6], c2, c3, c1);

    mul_add_c(a[2], b[5], c2, c3, c1);

    mul_add_c(a[3], b[4], c2, c3, c1);

    mul_add_c(a[4], b[3], c2, c3, c1);

    mul_add_c(a[5], b[2], c2, c3, c1);

    mul_add_c(a[6], b[1], c2, c3, c1);

    mul_add_c(a[7], b[0], c2, c3, c1);

    r[7] = c2;

    c2 = 0;

    mul_add_c(a[7], b[1], c3, c1, c2);

    mul_add_c(a[6], b[2], c3, c1, c2);

    mul_add_c(a[5], b[3], c3, c1, c2);

    mul_add_c(a[4], b[4], c3, c1, c2);

    mul_add_c(a[3], b[5], c3, c1, c2);

    mul_add_c(a[2], b[6], c3, c1, c2);

    mul_add_c(a[1], b[7], c3, c1, c2);

    r[8] = c3;

    c3 = 0;

    mul_add_c(a[2], b[7], c1, c2, c3);

    mul_add_c(a[3], b[6], c1, c2, c3);

    mul_add_c(a[4], b[5], c1, c2, c3);

    mul_add_c(a[5], b[4], c1, c2, c3);

    mul_add_c(a[6], b[3], c1, c2, c3);

    mul_add_c(a[7], b[2], c1, c2, c3);

    r[9] = c1;

    c1 = 0;

    mul_add_c(a[7], b[3], c2, c3, c1);

    mul_add_c(a[6], b[4], c2, c3, c1);

    mul_add_c(a[5], b[5], c2, c3, c1);

    mul_add_c(a[4], b[6], c2, c3, c1);

    mul_add_c(a[3], b[7], c2, c3, c1);

    r[10] = c2;

    c2 = 0;

    mul_add_c(a[4], b[7], c3, c1, c2);

    mul_add_c(a[5], b[6], c3, c1, c2);

    mul_add_c(a[6], b[5], c3, c1, c2);

    mul_add_c(a[7], b[4], c3, c1, c2);

    r[11] = c3;

    c3 = 0;

    mul_add_c(a[7], b[5], c1, c2, c3);

    mul_add_c(a[6], b[6], c1, c2, c3);

    mul_add_c(a[5], b[7], c1, c2, c3);

    r[12] = c1;

    c1 = 0;

    mul_add_c(a[6], b[7], c2, c3, c1);

    mul_add_c(a[7], b[6], c2, c3, c1);

    r[13] = c2;

    c2 = 0;

    mul_add_c(a[7], b[7], c3, c1, c2);

    r[14] = c3;

    r[15] = c1;

}

void bn_mul_comba4(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b)

{

    BN_ULONG c1, c2, c3;

    c1 = 0;

    c2 = 0;

    c3 = 0;

    mul_add_c(a[0], b[0], c1, c2, c3);

    r[0] = c1;

    c1 = 0;

    mul_add_c(a[0], b[1], c2, c3, c1);

    mul_add_c(a[1], b[0], c2, c3, c1);

    r[1] = c2;

    c2 = 0;

    mul_add_c(a[2], b[0], c3, c1, c2);

    mul_add_c(a[1], b[1], c3, c1, c2);

    mul_add_c(a[0], b[2], c3, c1, c2);

    r[2] = c3;

    c3 = 0;

    mul_add_c(a[0], b[3], c1, c2, c3);

    mul_add_c(a[1], b[2], c1, c2, c3);

    mul_add_c(a[2], b[1], c1, c2, c3);

    mul_add_c(a[3], b[0], c1, c2, c3);

    r[3] = c1;

    c1 = 0;

    mul_add_c(a[3], b[1], c2, c3, c1);

    mul_add_c(a[2], b[2], c2, c3, c1);

    mul_add_c(a[1], b[3], c2, c3, c1);

    r[4] = c2;

    c2 = 0;

    mul_add_c(a[2], b[3], c3, c1, c2);

    mul_add_c(a[3], b[2], c3, c1, c2);

    r[5] = c3;

    c3 = 0;

    mul_add_c(a[3], b[3], c1, c2, c3);

    r[6] = c1;

    r[7] = c2;

}

void bn_sqr_comba8(BN_ULONG *r, const BN_ULONG *a)

{

    BN_ULONG c1, c2, c3;

    c1 = 0;

    c2 = 0;

    c3 = 0;

    sqr_add_c(a, 0, c1, c2, c3);

    r[0] = c1;

    c1 = 0;

    sqr_add_c2(a, 1, 0, c2, c3, c1);

    r[1] = c2;

    c2 = 0;

    sqr_add_c(a, 1, c3, c1, c2);

    sqr_add_c2(a, 2, 0, c3, c1, c2);

    r[2] = c3;

    c3 = 0;

    sqr_add_c2(a, 3, 0, c1, c2, c3);

    sqr_add_c2(a, 2, 1, c1, c2, c3);

    r[3] = c1;

    c1 = 0;

    sqr_add_c(a, 2, c2, c3, c1);

    sqr_add_c2(a, 3, 1, c2, c3, c1);

    sqr_add_c2(a, 4, 0, c2, c3, c1);

    r[4] = c2;

    c2 = 0;

    sqr_add_c2(a, 5, 0, c3, c1, c2);

    sqr_add_c2(a, 4, 1, c3, c1, c2);

    sqr_add_c2(a, 3, 2, c3, c1, c2);

    r[5] = c3;

    c3 = 0;

    sqr_add_c(a, 3, c1, c2, c3);

    sqr_add_c2(a, 4, 2, c1, c2, c3);

    sqr_add_c2(a, 5, 1, c1, c2, c3);

    sqr_add_c2(a, 6, 0, c1, c2, c3);

    r[6] = c1;

    c1 = 0;

    sqr_add_c2(a, 7, 0, c2, c3, c1);

    sqr_add_c2(a, 6, 1, c2, c3, c1);

    sqr_add_c2(a, 5, 2, c2, c3, c1);

    sqr_add_c2(a, 4, 3, c2, c3, c1);

    r[7] = c2;

    c2 = 0;

    sqr_add_c(a, 4, c3, c1, c2);

    sqr_add_c2(a, 5, 3, c3, c1, c2);

    sqr_add_c2(a, 6, 2, c3, c1, c2);

    sqr_add_c2(a, 7, 1, c3, c1, c2);

    r[8] = c3;

    c3 = 0;

    sqr_add_c2(a, 7, 2, c1, c2, c3);

    sqr_add_c2(a, 6, 3, c1, c2, c3);

    sqr_add_c2(a, 5, 4, c1, c2, c3);

    r[9] = c1;

    c1 = 0;

    sqr_add_c(a, 5, c2, c3, c1);

    sqr_add_c2(a, 6, 4, c2, c3, c1);

    sqr_add_c2(a, 7, 3, c2, c3, c1);

    r[10] = c2;

    c2 = 0;

    sqr_add_c2(a, 7, 4, c3, c1, c2);

    sqr_add_c2(a, 6, 5, c3, c1, c2);

    r[11] = c3;

    c3 = 0;

    sqr_add_c(a, 6, c1, c2, c3);

    sqr_add_c2(a, 7, 5, c1, c2, c3);

    r[12] = c1;

    c1 = 0;

    sqr_add_c2(a, 7, 6, c2, c3, c1);

    r[13] = c2;

    c2 = 0;

    sqr_add_c(a, 7, c3, c1, c2);

    r[14] = c3;

    r[15] = c1;

}

void bn_sqr_comba4(BN_ULONG *r, const BN_ULONG *a)

{

    BN_ULONG c1, c2, c3;

    c1 = 0;

    c2 = 0;

    c3 = 0;

    sqr_add_c(a, 0, c1, c2, c3);

    r[0] = c1;

    c1 = 0;

    sqr_add_c2(a, 1, 0, c2, c3, c1);

    r[1] = c2;

    c2 = 0;

    sqr_add_c(a, 1, c3, c1, c2);

    sqr_add_c2(a, 2, 0, c3, c1, c2);

    r[2] = c3;

    c3 = 0;

    sqr_add_c2(a, 3, 0, c1, c2, c3);

    sqr_add_c2(a, 2, 1, c1, c2, c3);

    r[3] = c1;

    c1 = 0;

    sqr_add_c(a, 2, c2, c3, c1);

    sqr_add_c2(a, 3, 1, c2, c3, c1);

    r[4] = c2;

    c2 = 0;

    sqr_add_c2(a, 3, 2, c3, c1, c2);

    r[5] = c3;

    c3 = 0;

    sqr_add_c(a, 3, c1, c2, c3);

    r[6] = c1;

    r[7] = c2;

}

#endif