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 | #if defined(LIBM_SCCS) && !defined(lint) |
17 | static char rcsid[] = "$NetBSD: k_sinf.c,v 1.4 1995/05/10 20:46:33 jtc Exp $" ; |
18 | #endif |
19 | |
20 | #include <float.h> |
21 | #include <math.h> |
22 | #include <math_private.h> |
23 | #include <math-underflow.h> |
24 | |
25 | static const float |
26 | half = 5.0000000000e-01,/* 0x3f000000 */ |
27 | S1 = -1.6666667163e-01, /* 0xbe2aaaab */ |
28 | S2 = 8.3333337680e-03, /* 0x3c088889 */ |
29 | S3 = -1.9841270114e-04, /* 0xb9500d01 */ |
30 | S4 = 2.7557314297e-06, /* 0x3638ef1b */ |
31 | S5 = -2.5050759689e-08, /* 0xb2d72f34 */ |
32 | S6 = 1.5896910177e-10; /* 0x2f2ec9d3 */ |
33 | |
34 | float __kernel_sinf(float x, float y, int iy) |
35 | { |
36 | float z,r,v; |
37 | int32_t ix; |
38 | GET_FLOAT_WORD(ix,x); |
39 | ix &= 0x7fffffff; /* high word of x */ |
40 | if(ix<0x32000000) /* |x| < 2**-27 */ |
41 | { |
42 | math_check_force_underflow (x); |
43 | if ((int) x == 0) |
44 | return x; /* generate inexact */ |
45 | } |
46 | z = x*x; |
47 | v = z*x; |
48 | r = S2+z*(S3+z*(S4+z*(S5+z*S6))); |
49 | if(iy==0) return x+v*(S1+z*r); |
50 | else return x-((z*(half*y-v*r)-y)-v*S1); |
51 | } |
52 | |