/* * Copyright (c) 2006 Apple Computer, Inc. All Rights Reserved. * * @APPLE_LICENSE_OSREFERENCE_HEADER_START@ * * This file contains Original Code and/or Modifications of Original Code * as defined in and that are subject to the Apple Public Source License * Version 2.0 (the 'License'). You may not use this file except in * compliance with the License. The rights granted to you under the * License may not be used to create, or enable the creation or * redistribution of, unlawful or unlicensed copies of an Apple operating * system, or to circumvent, violate, or enable the circumvention or * violation of, any terms of an Apple operating system software license * agreement. * * Please obtain a copy of the License at * http://www.opensource.apple.com/apsl/ and read it before using this * file. * * The Original Code and all software distributed under the License are * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. * Please see the License for the specific language governing rights and * limitations under the License. * * @APPLE_LICENSE_OSREFERENCE_HEADER_END@ */ /* Copyright (c) 1992, 1997-1998 Apple Computer, Inc. All rights reserved. * * File: machdep/ppc/libc/ffs.s * * int ffs(int value) * * DESCRIPTION * The ffs() function finds the first bit set in value and returns the * index of that bit. Bits are numbered starting from 1, starting at * the right-most bit. A return value of 0 means that the argument was * * HISTORY * 14-Aug-1998 Umesh Vaishampayan (umeshv@apple.com) * Optimized! * * 10-Mar-1998 Matt Watson (mwatson@apple.com) * Correctified * * 19-Jan-1998 Matt Watson (mwatson@apple.com) * Simplified * * 24-Jan-1997 Umesh Vaishampayan (umeshv@NeXT.com) * Ported to PPC. */ .text .align 4 .globl _ffs _ffs: /* Cycles */ neg r0,r3 /* 0 */ and r3,r0,r3 /* 1 */ li r4, 32 /* 1 */ cntlzw r3,r3 /* 2 */ subf r3,r3,r4 /* 3 */ blr .globl _abs _abs: srawi r0,r3,31 xor r3,r0,r3 subf r3,r0,r3 blr