59 lines
2.0 KiB
C
59 lines
2.0 KiB
C
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/*-
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* Copyright (c) 2005 David Schultz <das@FreeBSD.ORG>
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*/
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#include <sys/cdefs.h>
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#include <fenv.h>
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#include <math.h>
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#ifndef type
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__FBSDID("$FreeBSD$");
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#define type double
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#define roundit rint
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#define dtype long
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#define fn lrint
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#endif
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/*
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* C99 says we should not raise a spurious inexact exception when an
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* invalid exception is raised. Unfortunately, the set of inputs
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* that overflows depends on the rounding mode when 'dtype' has more
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* significant bits than 'type'. Hence, we bend over backwards for the
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* sake of correctness; an MD implementation could be more efficient.
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*/
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dtype
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fn(type x)
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{
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fenv_t env;
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dtype d;
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feholdexcept(&env);
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d = (dtype)roundit(x);
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if (fetestexcept(FE_INVALID))
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feclearexcept(FE_INEXACT);
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feupdateenv(&env);
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return (d);
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}
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