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author | Ulrich Drepper <drepper@gmail.com> | 2011-10-12 11:27:51 -0400 |
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committer | Ulrich Drepper <drepper@gmail.com> | 2011-10-12 11:27:51 -0400 |
commit | 0ac5ae2335292908f39031b1ea9fe8edce433c0f (patch) | |
tree | f9d26c8abc0de39d18d4c13e70f6022cdc6b461f /math/w_scalb.c | |
parent | a843a204a3e8a0dd53584dad3668771abaec84ac (diff) | |
download | glibc-0ac5ae2335292908f39031b1ea9fe8edce433c0f.tar glibc-0ac5ae2335292908f39031b1ea9fe8edce433c0f.tar.gz glibc-0ac5ae2335292908f39031b1ea9fe8edce433c0f.tar.bz2 glibc-0ac5ae2335292908f39031b1ea9fe8edce433c0f.zip |
Optimize libm
libm is now somewhat integrated with gcc's -ffinite-math-only option
and lots of the wrapper functions have been optimized.
Diffstat (limited to 'math/w_scalb.c')
-rw-r--r-- | math/w_scalb.c | 94 |
1 files changed, 43 insertions, 51 deletions
diff --git a/math/w_scalb.c b/math/w_scalb.c index 830f387644..91f3658a67 100644 --- a/math/w_scalb.c +++ b/math/w_scalb.c @@ -1,62 +1,54 @@ -/* @(#)w_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: w_scalb.c,v 1.6 1995/05/10 20:49:48 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. + + 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. -/* - * wrapper scalb(double x, double fn) is provide for - * passing various standard test suite. One - * should use scalbn() instead. - */ + 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 <errno.h> #include <math.h> #include <math_private.h> -#include <errno.h> -#ifdef __STDC__ -#ifdef _SCALB_INT - double __scalb(double x, int fn) /* wrapper scalb */ -#else - double __scalb(double x, double fn) /* wrapper scalb */ -#endif -#else - double __scalb(x,fn) /* wrapper scalb */ -#ifdef _SCALB_INT - double x; int fn; -#else - double x,fn; -#endif -#endif +static double +__attribute__ ((noinline)) +sysv_scalb (double x, double fn) { -#ifdef _IEEE_LIBM - return __ieee754_scalb(x,fn); -#else - double z; - z = __ieee754_scalb(x,fn); - if(_LIB_VERSION != _SVID_) return z; - if(!(__finite(z)||__isnan(z))&&__finite(x)) { - return __kernel_standard(x,(double)fn,32); /* scalb overflow */ - } - if(z==0.0&&z!=x) { - return __kernel_standard(x,(double)fn,33); /* scalb underflow */ - } -#ifndef _SCALB_INT - if(!__finite(fn)) __set_errno (ERANGE); -#endif - return z; -#endif + double z = __ieee754_scalb (x, fn); + + if (__builtin_expect (__isinf (z), 0)) + { + if (__finite (x)) + return __kernel_standard (x, fn, 32); /* scalb overflow */ + else + __set_errno (ERANGE); + } + else if (__builtin_expect (z == 0.0, 0) && z != x) + return __kernel_standard (x, fn, 33); /* scalb underflow */ + + return z; +} + + +/* Wrapper scalb */ +double +__scalb (double x, double fn) +{ + return (__builtin_expect (_LIB_VERSION == _SVID_, 0) + ? sysv_scalb (x, fn) + : __ieee754_scalb (x, fn)); } weak_alias (__scalb, scalb) #ifdef NO_LONG_DOUBLE |