/* s_logbf.c -- float version of s_logb.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 #include "math_private.h" float logbf(float x) { int32_t ix; GET_FLOAT_WORD(ix,x); ix &= 0x7fffffff; /* high |x| */ if(ix==0) return (float)-1.0/fabsf(x); if(ix>=0x7f800000) return x*x; if((ix>>=23)==0) /* IEEE 754 logb */ return -126.0; else return (float) (ix-127); }