| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* IEEE754 floating point arithmetic |
| 2 | * double precision: common utilities |
| 3 | */ |
| 4 | /* |
| 5 | * MIPS floating point support |
| 6 | * Copyright (C) 1994-2000 Algorithmics Ltd. |
| 7 | * http://www.algor.co.uk |
| 8 | * |
| 9 | * ######################################################################## |
| 10 | * |
| 11 | * This program is free software; you can distribute it and/or modify it |
| 12 | * under the terms of the GNU General Public License (Version 2) as |
| 13 | * published by the Free Software Foundation. |
| 14 | * |
| 15 | * This program is distributed in the hope it will be useful, but WITHOUT |
| 16 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 17 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| 18 | * for more details. |
| 19 | * |
| 20 | * You should have received a copy of the GNU General Public License along |
| 21 | * with this program; if not, write to the Free Software Foundation, Inc., |
| 22 | * 59 Temple Place - Suite 330, Boston MA 02111-1307, USA. |
| 23 | * |
| 24 | * ######################################################################## |
| 25 | */ |
| 26 | |
| 27 | |
| 28 | #include "ieee754dp.h" |
| 29 | |
| 30 | ieee754dp ieee754dp_fsp(ieee754sp x) |
| 31 | { |
| 32 | COMPXSP; |
| 33 | |
| 34 | EXPLODEXSP; |
| 35 | |
| 36 | CLEARCX; |
| 37 | |
| 38 | FLUSHXSP; |
| 39 | |
| 40 | switch (xc) { |
| 41 | case IEEE754_CLASS_SNAN: |
| 42 | SETCX(IEEE754_INVALID_OPERATION); |
| 43 | return ieee754dp_nanxcpt(ieee754dp_indef(), "fsp"); |
| 44 | case IEEE754_CLASS_QNAN: |
| 45 | return ieee754dp_nanxcpt(builddp(xs, |
| 46 | DP_EMAX + 1 + DP_EBIAS, |
| 47 | ((u64) xm |
| 48 | << (DP_MBITS - |
| 49 | SP_MBITS))), "fsp", |
| 50 | x); |
| 51 | case IEEE754_CLASS_INF: |
| 52 | return ieee754dp_inf(xs); |
| 53 | case IEEE754_CLASS_ZERO: |
| 54 | return ieee754dp_zero(xs); |
| 55 | case IEEE754_CLASS_DNORM: |
| 56 | /* normalize */ |
| 57 | while ((xm >> SP_MBITS) == 0) { |
| 58 | xm <<= 1; |
| 59 | xe--; |
| 60 | } |
| 61 | break; |
| 62 | case IEEE754_CLASS_NORM: |
| 63 | break; |
| 64 | } |
| 65 | |
| 66 | /* CANT possibly overflow,underflow, or need rounding |
| 67 | */ |
| 68 | |
| 69 | /* drop the hidden bit */ |
| 70 | xm &= ~SP_HIDDEN_BIT; |
| 71 | |
| 72 | return builddp(xs, xe + DP_EBIAS, |
| 73 | (u64) xm << (DP_MBITS - SP_MBITS)); |
| 74 | } |