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45 lines
1.4 KiB
C
45 lines
1.4 KiB
C
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/* Copyright (C) 2007 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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Contributed by Richard Henderson.
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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 <math.h>
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float
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__roundf (float x)
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{
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const float almost_half = 0x1.fffffep-2;
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const float two23 = 0x1.0p23;
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float r, tmp;
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__asm (
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#ifdef _IEEE_FP_INEXACT
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"adds/suic %2, %3, %1\n\tsubs/suic %1, %3, %0"
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#else
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"adds/suc %2, %3, %1\n\tsubs/suc %1, %3, %0"
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#endif
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: "=&f"(r), "=&f"(tmp)
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: "f"(fabsf (x) + almost_half), "f"(two23));
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/* round(-0) == -0, and in general we'll always have the same
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sign as our input. */
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return copysignf (r, x);
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}
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weak_alias (__roundf, roundf)
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