1 /* s_asinhf.c -- float version of s_asinh.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 one = 1.0000000000e+00, /* 0x3F800000 */ 21 ln2 = 6.9314718246e-01, /* 0x3f317218 */ 22 huge= 1.0000000000e+30; 23 24 float 25 asinhf(float x) 26 { 27 float t,w; 28 int32_t hx,ix; 29 GET_FLOAT_WORD(hx,x); 30 ix = hx&0x7fffffff; 31 if(ix>=0x7f800000) return x+x; /* x is inf or NaN */ 32 if(ix< 0x31800000) { /* |x|<2**-28 */ 33 if(huge+x>one) return x; /* return x inexact except 0 */ 34 } 35 if(ix>0x4d800000) { /* |x| > 2**28 */ 36 w = logf(fabsf(x))+ln2; 37 } else if (ix>0x40000000) { /* 2**28 > |x| > 2.0 */ 38 t = fabsf(x); 39 w = logf((float)2.0*t+one/(sqrtf(x*x+one)+t)); 40 } else { /* 2.0 > |x| > 2**-28 */ 41 t = x*x; 42 w =log1pf(fabsf(x)+t/(one+sqrtf(one+t))); 43 } 44 if(hx>0) return w; else return -w; 45 } 46