| Ben Elliston | 473a74b | 2005-11-28 22:30:30 +0000 | [diff] [blame^] | 1 | /* Temporary support for a libc-like fp environment for decimal float. |
| 2 | Copyright (C) 2005 Free Software Foundation, Inc. |
| 3 | |
| 4 | This file is part of GCC. |
| 5 | |
| 6 | GCC is free software; you can redistribute it and/or modify it under |
| 7 | the terms of the GNU General Public License as published by the Free |
| 8 | Software Foundation; either version 2, or (at your option) any later |
| 9 | version. |
| 10 | |
| 11 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY |
| 12 | WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 13 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| 14 | for more details. |
| 15 | |
| 16 | You should have received a copy of the GNU General Public License |
| 17 | along with GCC; see the file COPYING. If not, write to the Free |
| 18 | Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA |
| 19 | 02110-1301, USA. */ |
| 20 | |
| 21 | #include "decContext.h" |
| 22 | |
| 23 | #define FE_DEC_DOWNWARD 0 |
| 24 | #define FE_DEC_TONEAREST 1 |
| 25 | #define FE_DEC_TONEARESTFROMZERO 2 |
| 26 | #define FE_DEC_TOWARDZERO 3 |
| 27 | #define FE_DEC_UPWARD 4 |
| 28 | #define FE_DEC_MAX 5 |
| 29 | |
| 30 | extern void __dfp_set_round (int); |
| 31 | extern int __dfp_get_round (void); |
| 32 | extern enum rounding __decGetRound (void); |
| 33 | |
| 34 | /* FIXME: these should be in thread-local storage for runtime support. */ |
| 35 | static enum rounding __dfp_rounding_mode = DEC_ROUND_HALF_EVEN; |
| 36 | |
| 37 | /* Set the decNumber rounding mode from the FE_DEC_* value in MODE. */ |
| 38 | |
| 39 | void |
| 40 | __dfp_set_round (int mode) |
| 41 | { |
| 42 | switch (mode) |
| 43 | { |
| 44 | case FE_DEC_DOWNWARD: |
| 45 | __dfp_rounding_mode = DEC_ROUND_FLOOR; break; |
| 46 | case FE_DEC_TONEAREST: |
| 47 | __dfp_rounding_mode = DEC_ROUND_HALF_EVEN; break; |
| 48 | case FE_DEC_TONEARESTFROMZERO: |
| 49 | __dfp_rounding_mode = DEC_ROUND_HALF_UP; break; |
| 50 | case FE_DEC_TOWARDZERO: |
| 51 | __dfp_rounding_mode = DEC_ROUND_DOWN; break; |
| 52 | case FE_DEC_UPWARD: |
| 53 | __dfp_rounding_mode = DEC_ROUND_CEILING; break; |
| 54 | default: |
| 55 | /* We can't use assert in libgcc, so just return the default mode. */ |
| 56 | __dfp_rounding_mode = DEC_ROUND_HALF_EVEN; break; |
| 57 | } |
| 58 | } |
| 59 | |
| 60 | /* Return the decNumber rounding mode as an FE_DEC_* value. */ |
| 61 | |
| 62 | int |
| 63 | __dfp_get_round (void) |
| 64 | { |
| 65 | int mode; |
| 66 | |
| 67 | switch (__dfp_rounding_mode) |
| 68 | { |
| 69 | case DEC_ROUND_FLOOR: |
| 70 | mode = FE_DEC_DOWNWARD; break; |
| 71 | case DEC_ROUND_HALF_EVEN: |
| 72 | mode = FE_DEC_TONEAREST; break; |
| 73 | case DEC_ROUND_HALF_UP: |
| 74 | mode = FE_DEC_TONEARESTFROMZERO; break; |
| 75 | case DEC_ROUND_DOWN: |
| 76 | mode = FE_DEC_TOWARDZERO; break; |
| 77 | case DEC_ROUND_CEILING: |
| 78 | mode = FE_DEC_UPWARD; break; |
| 79 | default: |
| 80 | /* We shouldn't get here, but can't use assert in libgcc. */ |
| 81 | mode = -1; |
| 82 | } |
| 83 | return mode; |
| 84 | } |
| 85 | |
| 86 | /* Return the decNumber version of the current rounding mode. */ |
| 87 | |
| 88 | enum rounding |
| 89 | __decGetRound (void) |
| 90 | { |
| 91 | return __dfp_rounding_mode; |
| 92 | } |