contrib/openbsd_libm/src/k_sinf.c

   1 /* k_sinf.c -- float version of k_sin.c
   2  * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
   3  */
   4
   5 /*
   6  * ====================================================
   7  * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
   8  *
   9  * Developed at SunPro, a Sun Microsystems, Inc. business.
  10  * Permission to use, copy, modify, and distribute this
  11  * software is freely granted, provided that this notice
  12  * is preserved.
  13  * ====================================================
  14  */
  15
  16 #include "math.h"
  17 #include "math_private.h"
  18
  19 static const float
  20 half =  5.0000000000e-01,/* 0x3f000000 */
  21 S1  = -1.6666667163e-01, /* 0xbe2aaaab */
  22 S2  =  8.3333337680e-03, /* 0x3c088889 */
  23 S3  = -1.9841270114e-04, /* 0xb9500d01 */
  24 S4  =  2.7557314297e-06, /* 0x3638ef1b */
  25 S5  = -2.5050759689e-08, /* 0xb2d72f34 */
  26 S6  =  1.5896910177e-10; /* 0x2f2ec9d3 */
  27
  28 float
  29 __kernel_sinf(float x, float y, int iy)
  30 {
  31         float z,r,v;
  32         int32_t ix;
  33         GET_FLOAT_WORD(ix,x);
  34         ix &= 0x7fffffff;                       /* high word of x */
  35         if(ix<0x32000000)                       /* |x| < 2**-27 */
  36            {if((int)x==0) return x;}            /* generate inexact */
  37         z       =  x*x;
  38         v       =  z*x;
  39         r       =  S2+z*(S3+z*(S4+z*(S5+z*S6)));
  40         if(iy==0) return x+v*(S1+z*r);
  41         else      return x-((z*(half*y-v*r)-y)-v*S1);
  42 }