| | 1 | /*- |
| | 2 | * Copyright (c) 1992, 1993 |
| | 3 | * The Regents of the University of California. All rights reserved. |
| | 4 | * |
| | 5 | * This software was developed by the Computer Systems Engineering group |
| | 6 | * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and |
| | 7 | * contributed to Berkeley. |
| | 8 | * |
| | 9 | * Redistribution and use in source and binary forms, with or without |
| | 10 | * modification, are permitted provided that the following conditions |
| | 11 | * are met: |
| | 12 | * 1. Redistributions of source code must retain the above copyright |
| | 13 | * notice, this list of conditions and the following disclaimer. |
| | 14 | * 2. Redistributions in binary form must reproduce the above copyright |
| | 15 | * notice, this list of conditions and the following disclaimer in the |
| | 16 | * documentation and/or other materials provided with the distribution. |
| | 17 | * 3. All advertising materials mentioning features or use of this software |
| | 18 | * must display the following acknowledgement: |
| | 19 | * This product includes software developed by the University of |
| | 20 | * California, Berkeley and its contributors. |
| | 21 | * 4. Neither the name of the University nor the names of its contributors |
| | 22 | * may be used to endorse or promote products derived from this software |
| | 23 | * without specific prior written permission. |
| | 24 | * |
| | 25 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
| | 26 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| | 27 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| | 28 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
| | 29 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| | 30 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| | 31 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| | 32 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| | 33 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| | 34 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| | 35 | * SUCH DAMAGE. |
| | 36 | * |
| | 37 | * $FreeBSD: src/sys/libkern/adddi3.c,v 1.5 1999/08/28 00:46:30 peter Exp $ |
| | 38 | * $DragonFly: src/sys/libkern/adddi3.c,v 1.3 2004/01/26 11:09:44 joerg Exp $ |
| | 39 | */ |
| | 40 | |
| | 41 | #include "quad.h" |
| | 42 | |
| | 43 | /* |
| | 44 | * Add two quads. This is trivial since a one-bit carry from a single |
| | 45 | * u_long addition x+y occurs if and only if the sum x+y is less than |
| | 46 | * either x or y (the choice to compare with x or y is arbitrary). |
| | 47 | */ |
| | 48 | quad_t |
| | 49 | __adddi3(quad_t a, quad_t b) |
| | 50 | { |
| | 51 | union uu aa, bb, sum; |
| | 52 | |
| | 53 | aa.q = a; |
| | 54 | bb.q = b; |
| | 55 | sum.ul[L] = aa.ul[L] + bb.ul[L]; |
| | 56 | sum.ul[H] = aa.ul[H] + bb.ul[H] + (sum.ul[L] < bb.ul[L]); |
| | 57 | return (sum.q); |
| | 58 | } |
projects / dragonfly.git / blame_incremental