Chris@42: /*
Chris@42:  * Copyright (c) 2003, 2007-14 Matteo Frigo
Chris@42:  * Copyright (c) 2003, 2007-14 Massachusetts Institute of Technology
Chris@42:  *
Chris@42:  * This program is free software; you can redistribute it and/or modify
Chris@42:  * it under the terms of the GNU General Public License as published by
Chris@42:  * the Free Software Foundation; either version 2 of the License, or
Chris@42:  * (at your option) any later version.
Chris@42:  *
Chris@42:  * This program is distributed in the hope that it will be useful,
Chris@42:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
Chris@42:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
Chris@42:  * GNU General Public License for more details.
Chris@42:  *
Chris@42:  * You should have received a copy of the GNU General Public License
Chris@42:  * along with this program; if not, write to the Free Software
Chris@42:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
Chris@42:  *
Chris@42:  */
Chris@42: 
Chris@42: 
Chris@42: #include "ifftw.h"
Chris@42: 
Chris@42: #if HAVE_NEON
Chris@42: 
Chris@42: /* check for an environment where signals are known to work */
Chris@42: #if defined(unix) || defined(linux)
Chris@42:   # include <signal.h>
Chris@42:   # include <setjmp.h>
Chris@42: 
Chris@42:   static jmp_buf jb;
Chris@42: 
Chris@42:   static void sighandler(int x)
Chris@42:   {
Chris@42:        UNUSED(x);
Chris@42:        longjmp(jb, 1);
Chris@42:   }
Chris@42: 
Chris@42:   static int really_have_neon(void)
Chris@42:   {
Chris@42:        void (*oldsig)(int);
Chris@42:        oldsig = signal(SIGILL, sighandler);
Chris@42:        if (setjmp(jb)) {
Chris@42: 	    signal(SIGILL, oldsig);
Chris@42: 	    return 0;
Chris@42:        } else {
Chris@42: 	    /* paranoia: encode the instruction in binary because the
Chris@42: 	       assembler may not recognize it without -mfpu=neon */
Chris@42: 	    /*asm volatile ("vand q0, q0, q0");*/
Chris@42: 	    asm volatile (".long 0xf2000150");
Chris@42: 	    signal(SIGILL, oldsig);
Chris@42: 	    return 1;
Chris@42:        }
Chris@42:   }
Chris@42: 
Chris@42:   int X(have_simd_neon)(void)
Chris@42:   {
Chris@42:        static int init = 0, res;
Chris@42: 
Chris@42:        if (!init) {
Chris@42: 	    res = really_have_neon();
Chris@42: 	    init = 1;
Chris@42:        }
Chris@42:        return res;
Chris@42:   }
Chris@42: 
Chris@42: 
Chris@42: #else
Chris@42: /* don't know how to autodetect NEON; assume it is present */
Chris@42:   int X(have_simd_neon)(void)
Chris@42:   {
Chris@42:        return 1;
Chris@42:   }
Chris@42: #endif
Chris@42: 
Chris@42: #endif