1 /* origin: FreeBSD /usr/src/lib/msun/src/e_scalbf.c */ 2 /* 3 * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. 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 #define _GNU_SOURCE 17 #include <math.h> 18 19 float scalbf(float x, float fn) 20 { 21 if (isnan(x) || isnan(fn)) return x*fn; 22 if (!isfinite(fn)) { 23 if (fn > 0.0f) 24 return x*fn; 25 else 26 return x/(-fn); 27 } 28 if (rintf(fn) != fn) return (fn-fn)/(fn-fn); 29 if ( fn > 65000.0f) return scalbnf(x, 65000); 30 if (-fn > 65000.0f) return scalbnf(x,-65000); 31 return scalbnf(x,(int)fn); 32 } 33