projects / apple / xnu.git / blame
| Commit | Line | Data |
|---|---|---|
| 1c79356b | 1 | /* |
| 5d5c5d0d A |
2 | * Copyright (c) 2000 Apple Computer, Inc. All rights reserved. |
| 3 | * | |
| 8f6c56a5 | 4 | * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ |
| 1c79356b | 5 | * |
| 8f6c56a5 A |
6 | * This file contains Original Code and/or Modifications of Original Code |
| 7 | * as defined in and that are subject to the Apple Public Source License | |
| 8 | * Version 2.0 (the 'License'). You may not use this file except in | |
| 9 | * compliance with the License. The rights granted to you under the License | |
| 10 | * may not be used to create, or enable the creation or redistribution of, | |
| 11 | * unlawful or unlicensed copies of an Apple operating system, or to | |
| 12 | * circumvent, violate, or enable the circumvention or violation of, any | |
| 13 | * terms of an Apple operating system software license agreement. | |
| 14 | * | |
| 15 | * Please obtain a copy of the License at | |
| 16 | * http://www.opensource.apple.com/apsl/ and read it before using this file. | |
| 17 | * | |
| 18 | * The Original Code and all software distributed under the License are | |
| 19 | * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER | |
| 20 | * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, | |
| 21 | * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, | |
| 22 | * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. | |
| 23 | * Please see the License for the specific language governing rights and | |
| 8ad349bb | 24 | * limitations under the License. |
| 8f6c56a5 A |
25 | * |
| 26 | * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ | |
| 1c79356b A |
27 | */ |
| 28 | /* Copyright (c) 1992, 1997-1998 Apple Computer, Inc. All rights reserved. | |
| 29 | * | |
| 30 | * File: machdep/ppc/libc/ffs.s | |
| 31 | * | |
| 32 | * int ffs(int value) | |
| 33 | * | |
| 34 | * DESCRIPTION | |
| 35 | * The ffs() function finds the first bit set in value and returns the | |
| 36 | * index of that bit. Bits are numbered starting from 1, starting at | |
| 37 | * the right-most bit. A return value of 0 means that the argument was | |
| 38 | * | |
| 39 | * HISTORY | |
| 40 | * 14-Aug-1998 Umesh Vaishampayan (umeshv@apple.com) | |
| 41 | * Optimized! | |
| 42 | * | |
| 43 | * 10-Mar-1998 Matt Watson (mwatson@apple.com) | |
| 44 | * Correctified | |
| 45 | * | |
| 46 | * 19-Jan-1998 Matt Watson (mwatson@apple.com) | |
| 47 | * Simplified | |
| 48 | * | |
| 49 | * 24-Jan-1997 Umesh Vaishampayan (umeshv@NeXT.com) | |
| 50 | * Ported to PPC. | |
| 51 | */ | |
| 52 | ||
| 53 | .text | |
| 54 | .align 4 | |
| 55 | .globl _ffs | |
| 56 | _ffs: /* Cycles */ | |
| 57 | neg r0,r3 /* 0 */ | |
| 58 | and r3,r0,r3 /* 1 */ | |
| 59 | li r4, 32 /* 1 */ | |
| 60 | cntlzw r3,r3 /* 2 */ | |
| 61 | subf r3,r3,r4 /* 3 */ | |
| 62 | blr | |
| 63 | ||
| 64 | .globl _abs | |
| 65 | _abs: | |
| 66 | srawi r0,r3,31 | |
| 67 | xor r3,r0,r3 | |
| 68 | subf r3,r0,r3 | |
| 69 | blr | |
| 70 |