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Optimize libm

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libm is now somewhat integrated with gcc's -ffinite-math-only option
and lots of the wrapper functions have been optimized.
This commit is contained in:
Ulrich Drepper
2011-10-12 11:27:51 -04:00
parent a843a204a3
commit 0ac5ae2335
270 changed files with 4557 additions and 5634 deletions
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112
math/e_scalb.c
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@@ -1,71 +1,59 @@
/* @(#)e_scalb.c 5.1 93/09/24 */
/*
* ====================================================
* 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.
* ====================================================
*/
/* Copyright (C) 2011 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@gmail.com>, 2011.
#if defined(LIBM_SCCS) && !defined(lint)
static char rcsid[] = "$NetBSD: e_scalb.c,v 1.6 1995/05/10 20:46:09 jtc Exp $";
#endif
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
/*
* __ieee754_scalb(x, fn) is provide for
* passing various standard test suite. One
* should use scalbn() instead.
*/
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <fenv.h>
#include <math.h>
#include <math_private.h>
#ifdef _SCALB_INT
#ifdef __STDC__
double __ieee754_scalb(double x, int fn)
#else
double __ieee754_scalb(x,fn)
double x; int fn;
#endif
#else
#ifdef __STDC__
double __ieee754_scalb(double x, double fn)
#else
double __ieee754_scalb(x,fn)
double x, fn;
#endif
#endif
static double
__attribute__ ((noinline))
invalid_fn (double x, double fn)
{
#ifdef _SCALB_INT
return __scalbn(x,fn);
#else
if (__isnan(x)||__isnan(fn)) return x*fn;
if (!__finite(fn)) {
if(fn>0.0) return x*fn;
else if (x == 0)
return x;
else if (!__finite (x))
{
# ifdef FE_INVALID
feraiseexcept (FE_INVALID);
# endif
return __nan ("");
}
else return x/(-fn);
}
if (__rint(fn)!=fn)
{
# ifdef FE_INVALID
feraiseexcept (FE_INVALID);
# endif
return __nan ("");
}
if ( fn > 65000.0) return __scalbn(x, 65000);
if (-fn > 65000.0) return __scalbn(x,-65000);
return __scalbn(x,(int)fn);
#endif
if (__rint (fn) != fn)
{
feraiseexcept (FE_INVALID);
return __nan ("");
}
else if (fn > 65000.0)
return __scalbn (x, 65000);
else
return __scalbn (x,-65000);
}
double
__ieee754_scalb (double x, double fn)
{
if (__builtin_expect (__isnan (x), 0))
return x * fn;
if (__builtin_expect (!__finite (fn), 0))
{
if (__isnan (fn) || fn > 0.0)
return x * fn;
if (x == 0.0)
return x;
return x / -fn;
}
if (__builtin_expect ((double) (int) fn != fn, 0))
return invalid_fn (x, fn);
return __scalbn (x, (int) fn);
}
strong_alias (__ieee754_scalb, __scalb_finite)