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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/e_scalbf.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/e_scalbf.c')
-rw-r--r-- | math/e_scalbf.c | 109 |
1 files changed, 50 insertions, 59 deletions
diff --git a/math/e_scalbf.c b/math/e_scalbf.c index 3caa535b12..61847d9a56 100644 --- a/math/e_scalbf.c +++ b/math/e_scalbf.c @@ -1,68 +1,59 @@ -/* e_scalbf.c -- float version of e_scalb.c. - * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. - */ +/* Copyright (C) 2011 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Ulrich Drepper <drepper@gmail.com>, 2011. -/* - * ==================================================== - * 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. - * ==================================================== - */ + 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. -#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 + 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__ - 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 + +static float +__attribute__ ((noinline)) +invalid_fn (float x, float fn) { -#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 + if (__rintf (fn) != fn) + { + feraiseexcept (FE_INVALID); + return __nan (""); + } + else if (fn > 65000.0f) + return __scalbnf (x, 65000); + else + return __scalbnf (x,-65000); +} + + +float +__ieee754_scalbf (float x, float fn) +{ + if (__builtin_expect (__isnanf (x), 0)) + return x * fn; + if (__builtin_expect (!__finitef (fn), 0)) + { + if (__isnanf (fn) || fn > 0.0f) + return x * fn; + if (x == 0.0f) + return x; + return x / -fn; + } + if (__builtin_expect ((float) (int) fn != fn, 0)) + return invalid_fn (x, fn); + + return __scalbnf (x, (int) fn); } +strong_alias (__ieee754_scalbf, __scalbf_finite) |