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/* 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
/* Multiplication performance enhancements for sparc v8+vis CPUs. */
#include "mpi-priv.h"
#include <stddef.h>
#include <sys/systeminfo.h>
#include <strings.h>
/* In the functions below, */
/* vector y must be 8-byte aligned, and n must be even */
/* returns carry out of high order word of result */
/* maximum n is 256 */
/* vector x += vector y * scaler a; where y is of length n words. */
extern mp_digit mul_add_inp(mp_digit *x, const mp_digit *y, int n, mp_digit a);
/* vector z = vector x + vector y * scaler a; where y is of length n words. */
extern mp_digit mul_add(mp_digit *z, const mp_digit *x, const mp_digit *y,
int n, mp_digit a);
/* v8 versions of these functions run on any Sparc v8 CPU. */
/* This trick works on Sparc V8 CPUs with the Workshop compilers. */
#define MP_MUL_DxD(a, b, Phi, Plo) \
{ \
unsigned long long product = (unsigned long long)a * b; \
Plo = (mp_digit)product; \
Phi = (mp_digit)(product >> MP_DIGIT_BIT); \
}
/* c = a * b */
static void
v8_mpv_mul_d(const mp_digit *a, mp_size a_len, mp_digit b, mp_digit *c)
{
#if !defined(MP_NO_MP_WORD)
mp_digit d = 0;
/* Inner product: Digits of a */
while (a_len--) {
mp_word w = ((mp_word)b * *a++) + d;
*c++ = ACCUM(w);
d = CARRYOUT(w);
}
*c = d;
#else
mp_digit carry = 0;
while (a_len--) {
mp_digit a_i = *a++;
mp_digit a0b0, a1b1;
MP_MUL_DxD(a_i, b, a1b1, a0b0);
a0b0 += carry;
if (a0b0 < carry)
++a1b1;
*c++ = a0b0;
carry = a1b1;
}
*c = carry;
#endif
}
/* c += a * b */
static void
v8_mpv_mul_d_add(const mp_digit *a, mp_size a_len, mp_digit b, mp_digit *c)
{
#if !defined(MP_NO_MP_WORD)
mp_digit d = 0;
/* Inner product: Digits of a */
while (a_len--) {
mp_word w = ((mp_word)b * *a++) + *c + d;
*c++ = ACCUM(w);
d = CARRYOUT(w);
}
*c = d;
#else
mp_digit carry = 0;
while (a_len--) {
mp_digit a_i = *a++;
mp_digit a0b0, a1b1;
MP_MUL_DxD(a_i, b, a1b1, a0b0);
a0b0 += carry;
if (a0b0 < carry)
++a1b1;
a0b0 += a_i = *c;
if (a0b0 < a_i)
++a1b1;
*c++ = a0b0;
carry = a1b1;
}
*c = carry;
#endif
}
/* Presently, this is only used by the Montgomery arithmetic code. */
/* c += a * b */
static void
v8_mpv_mul_d_add_prop(const mp_digit *a, mp_size a_len, mp_digit b, mp_digit *c)
{
#if !defined(MP_NO_MP_WORD)
mp_digit d = 0;
/* Inner product: Digits of a */
while (a_len--) {
mp_word w = ((mp_word)b * *a++) + *c + d;
*c++ = ACCUM(w);
d = CARRYOUT(w);
}
while (d) {
mp_word w = (mp_word)*c + d;
*c++ = ACCUM(w);
d = CARRYOUT(w);
}
#else
mp_digit carry = 0;
while (a_len--) {
mp_digit a_i = *a++;
mp_digit a0b0, a1b1;
MP_MUL_DxD(a_i, b, a1b1, a0b0);
a0b0 += carry;
if (a0b0 < carry)
++a1b1;
a0b0 += a_i = *c;
if (a0b0 < a_i)
++a1b1;
*c++ = a0b0;
carry = a1b1;
}
while (carry) {
mp_digit c_i = *c;
carry += c_i;
*c++ = carry;
carry = carry < c_i;
}
#endif
}
/* These functions run only on v8plus+vis or v9+vis CPUs. */
/* c = a * b */
void
s_mpv_mul_d(const mp_digit *a, mp_size a_len, mp_digit b, mp_digit *c)
{
mp_digit d;
mp_digit x[258];
if (a_len <= 256) {
if (a == c || ((ptrdiff_t)a & 0x7) != 0 || (a_len & 1) != 0) {
mp_digit *px;
px = (((ptrdiff_t)x & 0x7) != 0) ? x + 1 : x;
memcpy(px, a, a_len * sizeof(*a));
a = px;
if (a_len & 1) {
px[a_len] = 0;
}
}
s_mp_setz(c, a_len + 1);
d = mul_add_inp(c, a, a_len, b);
c[a_len] = d;
} else {
v8_mpv_mul_d(a, a_len, b, c);
}
}
/* c += a * b, where a is a_len words long. */
void
s_mpv_mul_d_add(const mp_digit *a, mp_size a_len, mp_digit b, mp_digit *c)
{
mp_digit d;
mp_digit x[258];
if (a_len <= 256) {
if (((ptrdiff_t)a & 0x7) != 0 || (a_len & 1) != 0) {
mp_digit *px;
px = (((ptrdiff_t)x & 0x7) != 0) ? x + 1 : x;
memcpy(px, a, a_len * sizeof(*a));
a = px;
if (a_len & 1) {
px[a_len] = 0;
}
}
d = mul_add_inp(c, a, a_len, b);
c[a_len] = d;
} else {
v8_mpv_mul_d_add(a, a_len, b, c);
}
}
/* c += a * b, where a is y words long. */
void
s_mpv_mul_d_add_prop(const mp_digit *a, mp_size a_len, mp_digit b, mp_digit *c)
{
mp_digit d;
mp_digit x[258];
if (a_len <= 256) {
if (((ptrdiff_t)a & 0x7) != 0 || (a_len & 1) != 0) {
mp_digit *px;
px = (((ptrdiff_t)x & 0x7) != 0) ? x + 1 : x;
memcpy(px, a, a_len * sizeof(*a));
a = px;
if (a_len & 1) {
px[a_len] = 0;
}
}
d = mul_add_inp(c, a, a_len, b);
if (d) {
c += a_len;
do {
mp_digit sum = d + *c;
*c++ = sum;
d = sum < d;
} while (d);
}
} else {
v8_mpv_mul_d_add_prop(a, a_len, b, c);
}
}