/* s_ilogbf.c -- float version of s_ilogb.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. * ==================================================== */ #ifndef lint static char rcsid[] = "$FreeBSD: src/lib/msun/src/s_ilogbf.c,v 1.7 2004/10/09 17:14:28 stefanf Exp $"; #endif #include <limits.h> #include "math.h" #include "math_private.h" int ilogbf(float x) { int32_t hx,ix; GET_FLOAT_WORD(hx,x); hx &= 0x7fffffff; if(hx<0x00800000) { if(hx==0) return FP_ILOGB0; else /* subnormal x */ for (ix = -126,hx<<=8; hx>0; hx<<=1) ix -=1; return ix; } else if (hx<0x7f800000) return (hx>>23)-127; else if (hx>0x7f800000) return FP_ILOGBNAN; else return INT_MAX; }