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/* Get the Decimal Float rounding mode mapped to the decNumber rounding mode
enumeration values.
Copyright (C) 2006 IBM Corporation.
Copyright (C) 2007-2015 Free Software Foundation, Inc.
This file is part of the Decimal Floating Point C Library.
Author(s): Ryan S. Arnold <rsa@us.ibm.com>
The Decimal Floating Point C Library is free software; you can
redistribute it and/or modify it under the terms of the GNU Lesser
General Public License version 2.1.
The Decimal Floating Point C Library is distributed in the hope that
it will be useful, but WITHOUT ANY WARRANTY; without even the implied
warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
the GNU Lesser General Public License version 2.1 for more details.
You should have received a copy of the GNU Lesser General Public
License version 2.1 along with the Decimal Floating Point C Library;
if not, write to the Free Software Foundation, Inc., 51 Franklin
Street, Fifth Floor, Boston, MA 02110-1301 USA.
Please see libdfp/COPYING.txt for more information. */
#include <fenv.h>
#include <dfpfenv_private.h>
#include <mapround.h>
#include <decContext.h>
int __dn_getround(void)
{
/* Only match on supported rounding modes. Power6[x] hardware supports the
* greatest number of rounding modes. The decNumber library supports
* one fewer than Power6[x] hardware. */
/* C Rounding Mode: Hardware Description
* DecNumber description
*
* FE_DEC_TONEAREST: 000 Round to nearest, ties to even.
* DEC_ROUND_HALF_EVEN
*
* FE_DEC_TOWARDZERO: 001 Round toward zero.
* DEC_ROUND_DOWN
*
* FE_DEC_UPWARD: 010 Round toward +Infinity
* DEC_ROUND_CEILING
*
* FE_DEC_DOWNWARD: 011 Round toward -Infinity
* DEC_ROUND_FLOOR
*
* FE_DEC_TONEARESTFROMZERO: 100 Round to nearest, ties away from zero
* DEC_ROUND_HALF_UP
*
* 5: 101 Round to nearest, ties toward zero
* DEC_ROUND_HALF_DOWN
*
* 6: 110 Round away from zero
* DEC_ROUND_UP
*
* 7: 111 Round for prepare for shorter precision
* Not supported by decNumber. */
switch(__fe_dec_getround())
{
case FE_DEC_TONEAREST:
return DEC_ROUND_HALF_EVEN;
case FE_DEC_TOWARDZERO:
return DEC_ROUND_DOWN;
case FE_DEC_UPWARD:
return DEC_ROUND_CEILING;
case FE_DEC_DOWNWARD:
return DEC_ROUND_FLOOR;
case FE_DEC_TONEARESTFROMZERO:
return DEC_ROUND_HALF_UP;
case 5:
return DEC_ROUND_HALF_DOWN;
case 6:
return DEC_ROUND_UP;
case 7:
default:
return DEC_ROUND_HALF_EVEN;
}
}
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