cannam@167: /*
cannam@167:  * Copyright (c) 2003, 2007-14 Matteo Frigo
cannam@167:  * Copyright (c) 2003, 2007-14 Massachusetts Institute of Technology
cannam@167:  *
cannam@167:  * This program is free software; you can redistribute it and/or modify
cannam@167:  * it under the terms of the GNU General Public License as published by
cannam@167:  * the Free Software Foundation; either version 2 of the License, or
cannam@167:  * (at your option) any later version.
cannam@167:  *
cannam@167:  * This program is distributed in the hope that it will be useful,
cannam@167:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
cannam@167:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
cannam@167:  * GNU General Public License for more details.
cannam@167:  *
cannam@167:  * You should have received a copy of the GNU General Public License
cannam@167:  * along with this program; if not, write to the Free Software
cannam@167:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
cannam@167:  *
cannam@167:  */
cannam@167: 
cannam@167: 
cannam@167: #include "kernel/ifftw.h"
cannam@167: 
cannam@167: #if HAVE_NEON
cannam@167: 
cannam@167: /* check for an environment where signals are known to work */
cannam@167: #if defined(unix) || defined(linux)
cannam@167:   # include <signal.h>
cannam@167:   # include <setjmp.h>
cannam@167: 
cannam@167:   static jmp_buf jb;
cannam@167: 
cannam@167:   static void sighandler(int x)
cannam@167:   {
cannam@167:        UNUSED(x);
cannam@167:        longjmp(jb, 1);
cannam@167:   }
cannam@167: 
cannam@167:   static int really_have_neon(void)
cannam@167:   {
cannam@167:        void (*oldsig)(int);
cannam@167:        oldsig = signal(SIGILL, sighandler);
cannam@167:        if (setjmp(jb)) {
cannam@167: 	    signal(SIGILL, oldsig);
cannam@167: 	    return 0;
cannam@167:        } else {
cannam@167: 	    /* paranoia: encode the instruction in binary because the
cannam@167: 	       assembler may not recognize it without -mfpu=neon */
cannam@167: 	    /*asm volatile ("vand q0, q0, q0");*/
cannam@167: 	    asm volatile (".long 0xf2000150");
cannam@167: 	    signal(SIGILL, oldsig);
cannam@167: 	    return 1;
cannam@167:        }
cannam@167:   }
cannam@167: 
cannam@167:   int X(have_simd_neon)(void)
cannam@167:   {
cannam@167:        static int init = 0, res;
cannam@167: 
cannam@167:        if (!init) {
cannam@167: 	    res = really_have_neon();
cannam@167: 	    init = 1;
cannam@167:        }
cannam@167:        return res;
cannam@167:   }
cannam@167: 
cannam@167: 
cannam@167: #else
cannam@167: /* don't know how to autodetect NEON; assume it is present */
cannam@167:   int X(have_simd_neon)(void)
cannam@167:   {
cannam@167:        return 1;
cannam@167:   }
cannam@167: #endif
cannam@167: 
cannam@167: #endif