1 /* kf_sin.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 "fdlibm.h" 17 18 #ifdef __STDC__ 19 static const float 20 #else 21 static float 22 #endif 23 half = 5.0000000000e-01,/* 0x3f000000 */ 24 S1 = -1.6666667163e-01, /* 0xbe2aaaab */ 25 S2 = 8.3333337680e-03, /* 0x3c088889 */ 26 S3 = -1.9841270114e-04, /* 0xb9500d01 */ 27 S4 = 2.7557314297e-06, /* 0x3638ef1b */ 28 S5 = -2.5050759689e-08, /* 0xb2d72f34 */ 29 S6 = 1.5896910177e-10; /* 0x2f2ec9d3 */ 30 31 #ifdef __STDC__ __kernel_sinf(float x,float y,int iy)32 float __kernel_sinf(float x, float y, int iy) 33 #else 34 float __kernel_sinf(x, y, iy) 35 float x,y; int iy; /* iy=0 if y is zero */ 36 #endif 37 { 38 float z,r,v; 39 __int32_t ix; 40 GET_FLOAT_WORD(ix,x); 41 ix &= 0x7fffffff; /* high word of x */ 42 if(ix<0x32000000) /* |x| < 2**-27 */ 43 {if((int)x==0) return x;} /* generate inexact */ 44 z = x*x; 45 v = z*x; 46 r = S2+z*(S3+z*(S4+z*(S5+z*S6))); 47 if(iy==0) return x+v*(S1+z*r); 48 else return x-((z*(half*y-v*r)-y)-v*S1); 49 } 50