cannam@127: /*
cannam@127:  * Copyright (c) 2003, 2007-14 Matteo Frigo
cannam@127:  * Copyright (c) 2003, 2007-14 Massachusetts Institute of Technology
cannam@127:  *
cannam@127:  * This program is free software; you can redistribute it and/or modify
cannam@127:  * it under the terms of the GNU General Public License as published by
cannam@127:  * the Free Software Foundation; either version 2 of the License, or
cannam@127:  * (at your option) any later version.
cannam@127:  *
cannam@127:  * This program is distributed in the hope that it will be useful,
cannam@127:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
cannam@127:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
cannam@127:  * GNU General Public License for more details.
cannam@127:  *
cannam@127:  * You should have received a copy of the GNU General Public License
cannam@127:  * along with this program; if not, write to the Free Software
cannam@127:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
cannam@127:  *
cannam@127:  */
cannam@127: 
cannam@127: 
cannam@127: #include "ifftw.h"
cannam@127: 
cannam@127: #if HAVE_NEON
cannam@127: 
cannam@127: /* check for an environment where signals are known to work */
cannam@127: #if defined(unix) || defined(linux)
cannam@127:   # include <signal.h>
cannam@127:   # include <setjmp.h>
cannam@127: 
cannam@127:   static jmp_buf jb;
cannam@127: 
cannam@127:   static void sighandler(int x)
cannam@127:   {
cannam@127:        UNUSED(x);
cannam@127:        longjmp(jb, 1);
cannam@127:   }
cannam@127: 
cannam@127:   static int really_have_neon(void)
cannam@127:   {
cannam@127:        void (*oldsig)(int);
cannam@127:        oldsig = signal(SIGILL, sighandler);
cannam@127:        if (setjmp(jb)) {
cannam@127: 	    signal(SIGILL, oldsig);
cannam@127: 	    return 0;
cannam@127:        } else {
cannam@127: 	    /* paranoia: encode the instruction in binary because the
cannam@127: 	       assembler may not recognize it without -mfpu=neon */
cannam@127: 	    /*asm volatile ("vand q0, q0, q0");*/
cannam@127: 	    asm volatile (".long 0xf2000150");
cannam@127: 	    signal(SIGILL, oldsig);
cannam@127: 	    return 1;
cannam@127:        }
cannam@127:   }
cannam@127: 
cannam@127:   int X(have_simd_neon)(void)
cannam@127:   {
cannam@127:        static int init = 0, res;
cannam@127: 
cannam@127:        if (!init) {
cannam@127: 	    res = really_have_neon();
cannam@127: 	    init = 1;
cannam@127:        }
cannam@127:        return res;
cannam@127:   }
cannam@127: 
cannam@127: 
cannam@127: #else
cannam@127: /* don't know how to autodetect NEON; assume it is present */
cannam@127:   int X(have_simd_neon)(void)
cannam@127:   {
cannam@127:        return 1;
cannam@127:   }
cannam@127: #endif
cannam@127: 
cannam@127: #endif