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0ac5ae2335
libm is now somewhat integrated with gcc's -ffinite-math-only option and lots of the wrapper functions have been optimized.
60 lines
1.6 KiB
C
60 lines
1.6 KiB
C
/* Copyright (C) 2011 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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Contributed by Ulrich Drepper <drepper@gmail.com>, 2011.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with the GNU C Library; if not, write to the Free
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Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
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02111-1307 USA. */
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#include <fenv.h>
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#include <math.h>
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#include <math_private.h>
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static float
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__attribute__ ((noinline))
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invalid_fn (float x, float fn)
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{
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if (__rintf (fn) != fn)
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{
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feraiseexcept (FE_INVALID);
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return __nan ("");
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}
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else if (fn > 65000.0f)
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return __scalbnf (x, 65000);
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else
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return __scalbnf (x,-65000);
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}
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float
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__ieee754_scalbf (float x, float fn)
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{
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if (__builtin_expect (__isnanf (x), 0))
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return x * fn;
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if (__builtin_expect (!__finitef (fn), 0))
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{
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if (__isnanf (fn) || fn > 0.0f)
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return x * fn;
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if (x == 0.0f)
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return x;
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return x / -fn;
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}
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if (__builtin_expect ((float) (int) fn != fn, 0))
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return invalid_fn (x, fn);
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return __scalbnf (x, (int) fn);
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}
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strong_alias (__ieee754_scalbf, __scalbf_finite)
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