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 | 22 | #include "ieee754sp.h" |
| b3a7ad2b | 23 | #include "ieee754dp.h" |
| 1da177e4 | 24 | |
| 2209bcb1 | 25 | union ieee754sp ieee754sp_fdp(union ieee754dp x) |
| 1da177e4 | 26 | { |
| 3f7cac41 RB |
27 | u32 rm; |
| 28 | ||
| 1da177e4 | 29 | COMPXDP; |
| 2209bcb1 | 30 | union ieee754sp nan; |
| 1da177e4 LT |
31 | |
| 32 | EXPLODEXDP; | |
| 33 | ||
| 9e8bad1f | 34 | ieee754_clearcx(); |
| 1da177e4 LT |
35 | |
| 36 | FLUSHXDP; | |
| 37 | ||
| 38 | switch (xc) { | |
| 39 | case IEEE754_CLASS_SNAN: | |
| 9e8bad1f | 40 | ieee754_setcx(IEEE754_INVALID_OPERATION); |
| 90efba36 | 41 | return ieee754sp_nanxcpt(ieee754sp_indef()); |
| 3f7cac41 | 42 | |
| 1da177e4 LT |
43 | case IEEE754_CLASS_QNAN: |
| 44 | nan = buildsp(xs, SP_EMAX + 1 + SP_EBIAS, (u32) | |
| ad8fb553 | 45 | (xm >> (DP_FBITS - SP_FBITS))); |
| 1da177e4 LT |
46 | if (!ieee754sp_isnan(nan)) |
| 47 | nan = ieee754sp_indef(); | |
| 90efba36 | 48 | return ieee754sp_nanxcpt(nan); |
| 3f7cac41 | 49 | |
| 1da177e4 LT |
50 | case IEEE754_CLASS_INF: |
| 51 | return ieee754sp_inf(xs); | |
| 3f7cac41 | 52 | |
| 1da177e4 LT |
53 | case IEEE754_CLASS_ZERO: |
| 54 | return ieee754sp_zero(xs); | |
| 3f7cac41 | 55 | |
| 1da177e4 LT |
56 | case IEEE754_CLASS_DNORM: |
| 57 | /* can't possibly be sp representable */ | |
| 9e8bad1f RB |
58 | ieee754_setcx(IEEE754_UNDERFLOW); |
| 59 | ieee754_setcx(IEEE754_INEXACT); | |
| 56a64733 RB |
60 | if ((ieee754_csr.rm == FPU_CSR_RU && !xs) || |
| 61 | (ieee754_csr.rm == FPU_CSR_RD && xs)) | |
| 90efba36 RB |
62 | return ieee754sp_mind(xs); |
| 63 | return ieee754sp_zero(xs); | |
| 3f7cac41 | 64 | |
| 1da177e4 LT |
65 | case IEEE754_CLASS_NORM: |
| 66 | break; | |
| 67 | } | |
| 68 | ||
| 3f7cac41 RB |
69 | /* |
| 70 | * Convert from DP_FBITS to SP_FBITS+3 with sticky right shift. | |
| 71 | */ | |
| 72 | rm = (xm >> (DP_FBITS - (SP_FBITS + 3))) | | |
| 73 | ((xm << (64 - (DP_FBITS - (SP_FBITS + 3)))) != 0); | |
| 1da177e4 | 74 | |
| 3f7cac41 | 75 | return ieee754sp_format(xs, xe, rm); |
| 1da177e4 | 76 | } |