Home | History | Annotate | Line # | Download | only in src 
      1 /*	$NetBSD: s_sinl.c,v 1.3 2024/04/03 18:53:42 christos Exp $	*/
      2 
      3 /*-
      4  * SPDX-License-Identifier: BSD-2-Clause
      5  *
      6  * Copyright (c) 2007 Steven G. Kargl
      7  * All rights reserved.
      8  *
      9  * Redistribution and use in source and binary forms, with or without
     10  * modification, are permitted provided that the following conditions
     11  * are met:
     12  * 1. Redistributions of source code must retain the above copyright
     13  *    notice unmodified, this list of conditions, and the following
     14  *    disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     20  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     21  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     22  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
     23  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
     24  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
     28  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     29  */
     30 
     31 #include <sys/cdefs.h>
     32 __RCSID("$NetBSD: s_sinl.c,v 1.3 2024/04/03 18:53:42 christos Exp $");
     33 
     34 #include "namespace.h"
     35 #include <float.h>
     36 
     37 #ifdef __weak_alias
     38 __weak_alias(sinl, _sinl)
     39 #endif
     40 
     41 #include "math.h"
     42 #include "math_private.h"
     43 
     44 #ifdef __HAVE_LONG_DOUBLE
     45 
     46 #if LDBL_MANT_DIG == 64
     47 #include "../ld80/e_rem_pio2l.h"
     48 #include "../ld80/k_sinl.c"
     49 #elif LDBL_MANT_DIG == 113
     50 #include "../ld128/e_rem_pio2l.h"
     51 #include "../ld128/k_sinl.c"
     52 #else
     53 #error "Unsupported long double format"
     54 #endif
     55 
     56 long double
     57 sinl(long double x)
     58 {
     59 	union ieee_ext_u z;
     60 	int e0, s;
     61 	long double y[2];
     62 	long double hi, lo;
     63 
     64 	z.extu_ld = x;
     65 	s = z.extu_sign;
     66 	z.extu_sign = 0;
     67 
     68 	/* If x = +-0 or x is a subnormal number, then sin(x) = x */
     69 	if (z.extu_exp == 0)
     70 		return (x);
     71 
     72 	/* If x = NaN or Inf, then sin(x) = NaN. */
     73 	if (z.extu_exp == 32767)
     74 		return ((x - x) / (x - x));
     75 
     76 	ENTERI();
     77 
     78 	/* Optimize the case where x is already within range. */
     79 	if (z.extu_ld < M_PI_4) {
     80 		hi = __kernel_sinl(z.extu_ld, 0, 0);
     81 		RETURNI(s ? -hi : hi);
     82 	}
     83 
     84 	e0 = __ieee754_rem_pio2l(x, y);
     85 	hi = y[0];
     86 	lo = y[1];
     87 
     88 	switch (e0 & 3) {
     89 	case 0:
     90 	    hi = __kernel_sinl(hi, lo, 1);
     91 	    break;
     92 	case 1:
     93 	    hi = __kernel_cosl(hi, lo);
     94 	    break;
     95 	case 2:
     96 	    hi = - __kernel_sinl(hi, lo, 1);
     97 	    break;
     98 	case 3:
     99 	    hi = - __kernel_cosl(hi, lo);
    100 	    break;
    101 	}
    102 
    103 	RETURNI(hi);
    104 }
    105 
    106 #else
    107 
    108 long double
    109 sinl(long double x)
    110 {
    111 	return sin(x);
    112 }
    113 
    114 #endif /* __HAVE_LONG_DOUBLE */
    115