Current Path : /usr/src/lib/msun/src/ |
FreeBSD hs32.drive.ne.jp 9.1-RELEASE FreeBSD 9.1-RELEASE #1: Wed Jan 14 12:18:08 JST 2015 root@hs32.drive.ne.jp:/sys/amd64/compile/hs32 amd64 |
Current File : //usr/src/lib/msun/src/e_asinf.c |
/* e_asinf.c -- float version of e_asin.c. * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. */ /* * ==================================================== * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. * * Developed at SunPro, a Sun Microsystems, Inc. business. * Permission to use, copy, modify, and distribute this * software is freely granted, provided that this notice * is preserved. * ==================================================== */ #include <sys/cdefs.h> __FBSDID("$FreeBSD: release/9.1.0/lib/msun/src/e_asinf.c 181405 2008-08-08 00:21:27Z das $"); #include "math.h" #include "math_private.h" static const float one = 1.0000000000e+00, /* 0x3F800000 */ huge = 1.000e+30, /* coefficient for R(x^2) */ pS0 = 1.6666586697e-01, pS1 = -4.2743422091e-02, pS2 = -8.6563630030e-03, qS1 = -7.0662963390e-01; static const double pio2 = 1.570796326794896558e+00; float __ieee754_asinf(float x) { double s; float t,w,p,q; int32_t hx,ix; GET_FLOAT_WORD(hx,x); ix = hx&0x7fffffff; if(ix>=0x3f800000) { /* |x| >= 1 */ if(ix==0x3f800000) /* |x| == 1 */ return x*pio2; /* asin(+-1) = +-pi/2 with inexact */ return (x-x)/(x-x); /* asin(|x|>1) is NaN */ } else if (ix<0x3f000000) { /* |x|<0.5 */ if(ix<0x39800000) { /* |x| < 2**-12 */ if(huge+x>one) return x;/* return x with inexact if x!=0*/ } t = x*x; p = t*(pS0+t*(pS1+t*pS2)); q = one+t*qS1; w = p/q; return x+x*w; } /* 1> |x|>= 0.5 */ w = one-fabsf(x); t = w*(float)0.5; p = t*(pS0+t*(pS1+t*pS2)); q = one+t*qS1; s = sqrt(t); w = p/q; t = pio2-2.0*(s+s*w); if(hx>0) return t; else return -t; }