POK
/home/jaouen/pok_official/pok/trunk/libpok/libm/e_scalbf.c
00001 /*
00002  *                               POK header
00003  * 
00004  * The following file is a part of the POK project. Any modification should
00005  * made according to the POK licence. You CANNOT use this file or a part of
00006  * this file is this part of a file for your own project
00007  *
00008  * For more information on the POK licence, please see our LICENCE FILE
00009  *
00010  * Please follow the coding guidelines described in doc/CODING_GUIDELINES
00011  *
00012  *                                      Copyright (c) 2007-2009 POK team 
00013  *
00014  * Created by julien on Fri Jan 30 14:41:34 2009 
00015  */
00016 
00017 /* e_scalbf.c -- float version of e_scalb.c.
00018  * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
00019  */
00020 
00021 /*
00022  * ====================================================
00023  * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
00024  *
00025  * Developed at SunPro, a Sun Microsystems, Inc. business.
00026  * Permission to use, copy, modify, and distribute this
00027  * software is freely granted, provided that this notice
00028  * is preserved.
00029  * ====================================================
00030  */
00031 
00032 #ifdef POK_NEEDS_LIBMATH
00033 
00034 #include <libm.h>
00035 #include "math_private.h"
00036 
00037 #ifdef _SCALB_INT
00038 float
00039 __ieee754_scalbf(float x, int fn)
00040 #else
00041 float
00042 __ieee754_scalbf(float x, float fn)
00043 #endif
00044 {
00045 #ifdef _SCALB_INT
00046         return scalbnf(x,fn);
00047 #else
00048         if (isnanf(x)||isnanf(fn)) return x*fn;
00049         if (!finitef(fn)) {
00050             if(fn>(float)0.0) return x*fn;
00051             else       return x/(-fn);
00052         }
00053         if (rintf(fn)!=fn) return (fn-fn)/(fn-fn);
00054         if ( fn > (float)65000.0) return scalbnf(x, 65000);
00055         if (-fn > (float)65000.0) return scalbnf(x,-65000);
00056         return scalbnf(x,(int)fn);
00057 #endif
00058 }
00059 #endif
00060