projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| 1da177e4 LT |
1 | /* IEEE754 floating point arithmetic |
| 2 | * double precision: common utilities | |
| 3 | */ | |
| 4 | /* | |
| 5 | * MIPS floating point support | |
| 6 | * Copyright (C) 1994-2000 Algorithmics Ltd. | |
| 1da177e4 LT |
7 | * |
| 8 | * ######################################################################## | |
| 9 | * | |
| 10 | * This program is free software; you can distribute it and/or modify it | |
| 11 | * under the terms of the GNU General Public License (Version 2) as | |
| 12 | * published by the Free Software Foundation. | |
| 13 | * | |
| 14 | * This program is distributed in the hope it will be useful, but WITHOUT | |
| 15 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
| 16 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
| 17 | * for more details. | |
| 18 | * | |
| 19 | * You should have received a copy of the GNU General Public License along | |
| 20 | * with this program; if not, write to the Free Software Foundation, Inc., | |
| 21 | * 59 Temple Place - Suite 330, Boston MA 02111-1307, USA. | |
| 22 | * | |
| 23 | * ######################################################################## | |
| 24 | */ | |
| 25 | ||
| 26 | ||
| 27 | #include "ieee754dp.h" | |
| 28 | ||
| 2209bcb1 | 29 | union ieee754dp ieee754dp_fint(int x) |
| 1da177e4 | 30 | { |
| ecf52d3c AN |
31 | u64 xm; |
| 32 | int xe; | |
| 33 | int xs; | |
| 1da177e4 | 34 | |
| 9e8bad1f | 35 | ieee754_clearcx(); |
| 1da177e4 | 36 | |
| 1da177e4 LT |
37 | if (x == 0) |
| 38 | return ieee754dp_zero(0); | |
| 39 | if (x == 1 || x == -1) | |
| 40 | return ieee754dp_one(x < 0); | |
| 41 | if (x == 10 || x == -10) | |
| 42 | return ieee754dp_ten(x < 0); | |
| 43 | ||
| 44 | xs = (x < 0); | |
| 45 | if (xs) { | |
| 46 | if (x == (1 << 31)) | |
| 47 | xm = ((unsigned) 1 << 31); /* max neg can't be safely negated */ | |
| 48 | else | |
| 49 | xm = -x; | |
| 50 | } else { | |
| 51 | xm = x; | |
| 52 | } | |
| 53 | ||
| 1da177e4 | 54 | /* normalize - result can never be inexact or overflow */ |
| ad8fb553 RB |
55 | xe = DP_FBITS; |
| 56 | while ((xm >> DP_FBITS) == 0) { | |
| 1da177e4 LT |
57 | xm <<= 1; |
| 58 | xe--; | |
| 59 | } | |
| 60 | return builddp(xs, xe + DP_EBIAS, xm & ~DP_HIDDEN_BIT); | |
| 1da177e4 LT |
61 | } |
| 62 | ||
| 2209bcb1 | 63 | union ieee754dp ieee754dp_funs(unsigned int u) |
| 1da177e4 LT |
64 | { |
| 65 | if ((int) u < 0) | |
| 66 | return ieee754dp_add(ieee754dp_1e31(), | |
| 67 | ieee754dp_fint(u & ~(1 << 31))); | |
| 68 | return ieee754dp_fint(u); | |
| 69 | } |