glibc/sysdeps/generic/e_scalbf.c

69 lines
1.5 KiB
C

/* e_scalbf.c -- float version of e_scalb.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.
* ====================================================
*/
#if defined(LIBM_SCCS) && !defined(lint)
static char rcsid[] = "$NetBSD: e_scalbf.c,v 1.3 1995/05/10 20:46:12 jtc Exp $";
#endif
#include <fenv.h>
#include "math.h"
#include "math_private.h"
#ifdef _SCALB_INT
#ifdef __STDC__
float __ieee754_scalbf(float x, int fn)
#else
float __ieee754_scalbf(x,fn)
float x; int fn;
#endif
#else
#ifdef __STDC__
float __ieee754_scalbf(float x, float fn)
#else
float __ieee754_scalbf(x,fn)
float x, fn;
#endif
#endif
{
#ifdef _SCALB_INT
return __scalbnf(x,fn);
#else
if (__isnanf(x)||__isnanf(fn)) return x*fn;
if (!__finitef(fn)) {
if(fn>(float)0.0) return x*fn;
else if (x == 0)
return x;
else if (!__finitef (x))
{
# ifdef FE_INVALID
feraiseexcept (FE_INVALID);
# endif
return __nanf ("");
}
else return x/(-fn);
}
if (__rintf(fn)!=fn)
{
# ifdef FE_INVALID
feraiseexcept (FE_INVALID);
# endif
return __nanf ("");
}
if ( fn > (float)65000.0) return __scalbnf(x, 65000);
if (-fn > (float)65000.0) return __scalbnf(x,-65000);
return __scalbnf(x,(int)fn);
#endif
}