0001-libc-Add-i386-version-of-fls-using-bsr.patch

vsrinivas, 05/24/2010 03:41 AM

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lib/libc/i386/string/Makefile.inc
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# $FreeBSD: src/lib/libc/i386/string/Makefile.inc,v 1.9 1999/08/27 23:59:29 peter Exp $
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# $DragonFly: src/lib/libc/i386/string/Makefile.inc,v 1.2 2003/06/17 04:26:43 dillon Exp $
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MDSRCS+=bcmp.S bcopy.S bzero.S ffs.S index.S memchr.S memcmp.S memcpy.S \
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MDSRCS+=bcmp.S bcopy.S bzero.S ffs.S fls.S index.S memchr.S memcmp.S memcpy.S \
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	memmove.S memset.S rindex.S strcat.S strchr.S strcmp.S strcpy.S \
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	strlen.S strncmp.S strrchr.S swab.S
lib/libc/i386/string/fls.S
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/*
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 * Copyright (c) 2010 The DragonFly Project
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 * All rights reserved.
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 *
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 * Redistribution and use in source and binary forms, with or without
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 * modification, are permitted provided that the following conditions
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 * are met:
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 * 1. Redistributions of source code must retain the above copyright
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 *    notice, this list of conditions and the following disclaimer.
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 * 2. Redistributions in binary form must reproduce the above copyright
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 *    notice, this list of conditions and the following disclaimer in the
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 *    documentation and/or other materials provided with the distribution.
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 * 3. The name of the author may not be used to endorse or promote products
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 *    derived from this software withough specific prior written permission
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 *
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 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
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 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
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 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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 */
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#include "DEFS.h"
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/*
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 * int fls(int value)
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 * 	Finds the highest set bit in a word. Bits are numbered from 1;
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 *	a return of 0 indicates that the word was 0.
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 */
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ENTRY(fls)
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	bsrl	4(%esp),%eax
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	jz	1
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	addl	$1, %eax
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	ret
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1:	xorl	%eax,%eax
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	ret
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