furnace/extern/fftw/simd-support/neon.c

77 lines
1.9 KiB
C

/*
* Copyright (c) 2003, 2007-14 Matteo Frigo
* Copyright (c) 2003, 2007-14 Massachusetts Institute of Technology
*
* 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; either version 2 of the License, or
* (at your option) any later version.
*
* 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 "kernel/ifftw.h"
#if HAVE_NEON
/* check for an environment where signals are known to work */
#if defined(unix) || defined(linux)
# include <signal.h>
# include <setjmp.h>
static jmp_buf jb;
static void sighandler(int x)
{
UNUSED(x);
longjmp(jb, 1);
}
static int really_have_neon(void)
{
void (*oldsig)(int);
oldsig = signal(SIGILL, sighandler);
if (setjmp(jb)) {
signal(SIGILL, oldsig);
return 0;
} else {
/* paranoia: encode the instruction in binary because the
assembler may not recognize it without -mfpu=neon */
/*asm volatile ("vand q0, q0, q0");*/
asm volatile (".long 0xf2000150");
signal(SIGILL, oldsig);
return 1;
}
}
int X(have_simd_neon)(void)
{
static int init = 0, res;
if (!init) {
res = really_have_neon();
init = 1;
}
return res;
}
#else
/* don't know how to autodetect NEON; assume it is present */
int X(have_simd_neon)(void)
{
return 1;
}
#endif
#endif