47 lines
2.6 KiB
C
47 lines
2.6 KiB
C
|
/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
|
|||
|
|
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
|
|||
|
|
╞══════════════════════════════════════════════════════════════════════════════╡
|
|||
|
|
│ Copyright 2020 Justine Alexandra Roberts Tunney │
|
|||
|
|
│ │
|
|||
|
|
│ This program is free software; you can redistribute it and/or modify │
|
|||
|
|
│ it under the terms of the GNU General Public License as published by │
|
|||
|
|
│ the Free Software Foundation; version 2 of the License. │
|
|||
|
|
│ │
|
|||
|
|
│ This program is distributed in the hope that it will be useful, but │
|
|||
|
|
│ WITHOUT ANY WARRANTY; without even the implied warranty of │
|
|||
|
|
│ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU │
|
|||
|
|
│ General Public License for more details. │
|
|||
|
|
│ │
|
|||
|
|
│ You should have received a copy of the GNU General Public License │
|
|||
|
|
│ along with this program; if not, write to the Free Software │
|
|||
|
|
│ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA │
|
|||
|
|
│ 02110-1301 USA │
|
|||
|
|
╚─────────────────────────────────────────────────────────────────────────────*/
|
|||
|
|
#include "libc/intrin/phsubsw.h"
|
|||
|
|
#include "libc/limits.h"
|
|||
|
|
#include "libc/macros.h"
|
|||
|
|
|
|||
|
|
/**
|
|||
|
|
* Subtracts adjacent shorts w/ saturation.
|
|||
|
|
*
|
|||
|
|
* @param 𝑎 [w/o] receives reduced 𝑏 and 𝑐 concatenated
|
|||
|
|
* @param 𝑏 [r/o] supplies four pairs of shorts
|
|||
|
|
* @param 𝑐 [r/o] supplies four pairs of shorts
|
|||
|
|
* @note goes fast w/ ssse3 (intel c. 2004, amd c. 2011)
|
|||
|
|
* @mayalias
|
|||
|
|
*/
|
|||
|
|
void(phsubsw)(int16_t a[8], const int16_t b[8], const int16_t c[8]) {
|
|||
|
|
int i, t[8];
|
|||
|
|
t[0] = b[0] - b[1];
|
|||
|
|
t[1] = b[2] - b[3];
|
|||
|
|
t[2] = b[4] - b[5];
|
|||
|
|
t[3] = b[6] - b[7];
|
|||
|
|
t[4] = c[0] - c[1];
|
|||
|
|
t[5] = c[2] - c[3];
|
|||
|
|
t[6] = c[4] - c[5];
|
|||
|
|
t[7] = c[6] - c[7];
|
|||
|
|
for (i = 0; i < 8; ++i) {
|
|||
|
|
a[i] = MIN(SHRT_MAX, MAX(SHRT_MIN, t[i]));
|
|||
|
|
}
|
|||
|
|
}
|