projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| 1da177e4 LT |
1 | /* IEEE754 floating point arithmetic |
| 2 | * single precision | |
| 3 | */ | |
| 4 | /* | |
| 5 | * MIPS floating point support | |
| 6 | * Copyright (C) 1994-2000 Algorithmics Ltd. | |
| 1da177e4 | 7 | * |
| 1da177e4 LT |
8 | * This program is free software; you can distribute it and/or modify it |
| 9 | * under the terms of the GNU General Public License (Version 2) as | |
| 10 | * published by the Free Software Foundation. | |
| 11 | * | |
| 12 | * This program is distributed in the hope it will be useful, but WITHOUT | |
| 13 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
| 14 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
| 15 | * for more details. | |
| 16 | * | |
| 17 | * You should have received a copy of the GNU General Public License along | |
| 18 | * with this program; if not, write to the Free Software Foundation, Inc., | |
| 3f7cac41 | 19 | * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| 1da177e4 LT |
20 | */ |
| 21 | ||
| 1da177e4 LT |
22 | #include "ieee754sp.h" |
| 23 | ||
| 2209bcb1 | 24 | union ieee754sp ieee754sp_fint(int x) |
| 1da177e4 | 25 | { |
| ecf52d3c AN |
26 | unsigned xm; |
| 27 | int xe; | |
| 28 | int xs; | |
| 1da177e4 | 29 | |
| 9e8bad1f | 30 | ieee754_clearcx(); |
| 1da177e4 | 31 | |
| 1da177e4 LT |
32 | if (x == 0) |
| 33 | return ieee754sp_zero(0); | |
| 34 | if (x == 1 || x == -1) | |
| 35 | return ieee754sp_one(x < 0); | |
| 36 | if (x == 10 || x == -10) | |
| 37 | return ieee754sp_ten(x < 0); | |
| 38 | ||
| 39 | xs = (x < 0); | |
| 40 | if (xs) { | |
| 41 | if (x == (1 << 31)) | |
| 42 | xm = ((unsigned) 1 << 31); /* max neg can't be safely negated */ | |
| 43 | else | |
| 44 | xm = -x; | |
| 45 | } else { | |
| 46 | xm = x; | |
| 47 | } | |
| ad8fb553 | 48 | xe = SP_FBITS + 3; |
| 1da177e4 | 49 | |
| ad8fb553 | 50 | if (xm >> (SP_FBITS + 1 + 3)) { |
| 1da177e4 LT |
51 | /* shunt out overflow bits |
| 52 | */ | |
| ad8fb553 | 53 | while (xm >> (SP_FBITS + 1 + 3)) { |
| 1da177e4 LT |
54 | SPXSRSX1(); |
| 55 | } | |
| 56 | } else { | |
| 57 | /* normalize in grs extended single precision | |
| 58 | */ | |
| ad8fb553 | 59 | while ((xm >> (SP_FBITS + 3)) == 0) { |
| 1da177e4 LT |
60 | xm <<= 1; |
| 61 | xe--; | |
| 62 | } | |
| 63 | } | |
| 90efba36 | 64 | return ieee754sp_format(xs, xe, xm); |
| 1da177e4 | 65 | } |