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/* $OpenBSD: flt_rounds.c,v 1.1 2017/01/11 18:09:24 patrick Exp $ */
/* $NetBSD: flt_rounds.c,v 1.1 2000/12/29 20:13:48 bjh21 Exp $ */
/*
* Copyright (c) 1996 Mark Brinicombe
* 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Mark Brinicombe
* for the NetBSD Project.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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 <sys/types.h>
#include <ieeefp.h>
#include <float.h>
static const int map[] = {
1, /* round to nearest */
2, /* round to positive infinity */
3, /* round to negative infinity */
0 /* round to zero */
};
/*
* Return the current FP rounding mode
*
* Returns:
* 0 - round to zero
* 1 - round to nearest
* 2 - round to postive infinity
* 3 - round to negative infinity
*
* ok all we need to do is get the current FP rounding mode
* index our map table and return the appropriate value.
*
* HOWEVER:
* The ARM FPA codes the rounding mode into the actual FP instructions
* so there is no such thing as a global rounding mode.
* The default is round to nearest if rounding is not explicitly specified.
* FP instructions generated by GCC will not explicitly specify a rounding
* mode.
*
* So the best we can do it to return the rounding mode FP instructions
* use if rounding is not specified which is round to nearest.
*
* This could change in the future with new floating point emulators or
* soft float FP libraries.
*/
int
__flt_rounds()
{
return(map[fpgetround()]);
}
DEF_STRONG(__flt_rounds);
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