diff options
Diffstat (limited to 'libc/dfp/sysdeps/dfp/fe_decround.c')
| -rw-r--r-- | libc/dfp/sysdeps/dfp/fe_decround.c | 71 |
1 files changed, 71 insertions, 0 deletions
diff --git a/libc/dfp/sysdeps/dfp/fe_decround.c b/libc/dfp/sysdeps/dfp/fe_decround.c new file mode 100644 index 000000000..d294f770a --- /dev/null +++ b/libc/dfp/sysdeps/dfp/fe_decround.c @@ -0,0 +1,71 @@ +/* Decimal Float fe_dec_getround and fe_dec_setround definitions. + Copyright (C) 2006 IBM Corporation. + + 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., 59 Temple Place, + Suite 330, Boston, MA 02111-1307 USA. + + Please see dfp/COPYING.txt for more information. */ + +#include <decroundtls.h> +#include <dfpfenv_private.h> + +int __fe_dec_setround(int __rounding_direction) +{ + + /* Only match on supported rounding modes. The decNum library supports + * additional ones that aren't valid C rounding modes. We also allow rounding + * modes to be set covertly for the three additional hardware rounding modes + * supported by Power6[x] that aren't in the DFP Draft Technical Report. */ + + /* 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. */ + if (__rounding_direction > 7) + return 1; + *__decrm_location() = __rounding_direction; + return 0; +} +strong_alias(__fe_dec_setround, fe_dec_setround) + +int __fe_dec_getround(void) +{ + return *__decrm_location(); +} +strong_alias(__fe_dec_getround, fe_dec_getround) + |