Rich Felker
2e77dc13f8
this is necessary to support archs where fenv is incomplete or unavailable (presently arm). fma, fmal, and the lrint family should work perfectly fine with this change; fmaf is slightly broken with respect to rounding as it depends on non-default rounding modes to do its work.
59 lines
2.1 KiB
C
59 lines
2.1 KiB
C
/* origin: FreeBSD /usr/src/lib/msun/src/s_lrint.c */
|
|
/*-
|
|
* Copyright (c) 2005 David Schultz <[email protected]>
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*/
|
|
|
|
#include <fenv.h>
|
|
#include "libm.h"
|
|
|
|
#ifndef type
|
|
#define type double
|
|
#define roundit rint
|
|
#define dtype long
|
|
#define fn lrint
|
|
#endif
|
|
|
|
/*
|
|
* C99 says we should not raise a spurious inexact exception when an
|
|
* invalid exception is raised. Unfortunately, the set of inputs
|
|
* that overflows depends on the rounding mode when 'dtype' has more
|
|
* significant bits than 'type'. Hence, we bend over backwards for the
|
|
* sake of correctness; an MD implementation could be more efficient.
|
|
*/
|
|
dtype fn(type x)
|
|
{
|
|
fenv_t env;
|
|
dtype d;
|
|
|
|
feholdexcept(&env);
|
|
d = (dtype)roundit(x);
|
|
#if defined(FE_INVALID) && defined(FE_INEXACT)
|
|
if (fetestexcept(FE_INVALID))
|
|
feclearexcept(FE_INEXACT);
|
|
#endif
|
|
feupdateenv(&env);
|
|
return d;
|
|
}
|