62 lines
2.0 KiB
C
62 lines
2.0 KiB
C
/*
|
|
* Copyright (c) 2017 Thomas Pornin <pornin@bolet.org>
|
|
*
|
|
* Permission is hereby granted, free of charge, to any person obtaining
|
|
* a copy of this software and associated documentation files (the
|
|
* "Software"), to deal in the Software without restriction, including
|
|
* without limitation the rights to use, copy, modify, merge, publish,
|
|
* distribute, sublicense, and/or sell copies of the Software, and to
|
|
* permit persons to whom the Software is furnished to do so, subject to
|
|
* the following conditions:
|
|
*
|
|
* The above copyright notice and this permission notice shall be
|
|
* included in all copies or substantial portions of the Software.
|
|
*
|
|
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
|
|
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
|
|
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
|
|
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
|
|
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
|
|
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
|
|
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
|
|
* SOFTWARE.
|
|
*/
|
|
|
|
#include "t_inner.h"
|
|
|
|
/* see inner.h */
|
|
void
|
|
br_i15_mulacc(uint16_t *d, const uint16_t *a, const uint16_t *b)
|
|
{
|
|
size_t alen, blen, u;
|
|
unsigned dl, dh;
|
|
|
|
alen = (pgm_read_word(&a[0]) + 15) >> 4;
|
|
blen = (pgm_read_word(&b[0]) + 15) >> 4;
|
|
|
|
/*
|
|
* Announced bit length of d[] will be the sum of the announced
|
|
* bit lengths of a[] and b[]; but the lengths are encoded.
|
|
*/
|
|
dl = (pgm_read_word(&a[0]) & 15) + (pgm_read_word(&b[0]) & 15);
|
|
dh = (pgm_read_word(&a[0]) >> 4) + (pgm_read_word(&b[0]) >> 4);
|
|
d[0] = (dh << 4) + dl + (~(uint32_t)(dl - 15) >> 31);
|
|
|
|
for (u = 0; u < blen; u ++) {
|
|
uint32_t f;
|
|
size_t v;
|
|
uint32_t cc;
|
|
|
|
f = pgm_read_word(&b[1 + u]);
|
|
cc = 0;
|
|
for (v = 0; v < alen; v ++) {
|
|
uint32_t z;
|
|
|
|
z = (uint32_t)d[1 + u + v] + MUL15(f, pgm_read_word(&a[1 + v])) + cc;
|
|
cc = z >> 15;
|
|
d[1 + u + v] = z & 0x7FFF;
|
|
}
|
|
d[1 + u + alen] = cc;
|
|
}
|
|
}
|