1 /* origin: FreeBSD /usr/src/lib/msun/src/e_asinf.c */
3 * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
6 * ====================================================
7 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
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
13 * ====================================================
19 one = 1.0000000000e+00, /* 0x3F800000 */
21 /* coefficients for R(x^2) */
22 pS0 = 1.6666586697e-01,
23 pS1 = -4.2743422091e-02,
24 pS2 = -8.6563630030e-03,
25 qS1 = -7.0662963390e-01;
28 pio2 = 1.570796326794896558e+00;
36 GET_FLOAT_WORD(hx, x);
38 if (ix >= 0x3f800000) { /* |x| >= 1 */
39 if (ix == 0x3f800000) /* |x| == 1 */
40 return x*pio2; /* asin(+-1) = +-pi/2 with inexact */
41 return (x-x)/(x-x); /* asin(|x|>1) is NaN */
42 } else if (ix < 0x3f000000) { /* |x|<0.5 */
43 if (ix < 0x39800000) { /* |x| < 2**-12 */
45 return x; /* return x with inexact if x!=0 */
48 p = t*(pS0+t*(pS1+t*pS2));
56 p = t*(pS0+t*(pS1+t*pS2));