remove obsolete i386 MD memchr implementation
bde reports (in a reply to r351700 commit mail): This uses scasb, which was last optimal on the 8086, or perhaps the original i386. On freefall, it is several times slower than the naive translation of the naive C code. Reported by: bde Reviewed by: kib, markj Sponsored by: The FreeBSD Foundation Differential Revision: https://reviews.freebsd.org/D21785
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@ -5,7 +5,6 @@ MDSRCS+= \
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bcopy.S \
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bcopy.S \
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bzero.S \
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bzero.S \
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ffs.S \
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ffs.S \
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memchr.S \
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memcmp.S \
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memcmp.S \
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memcpy.S \
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memcpy.S \
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memmove.S \
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memmove.S \
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@ -1,61 +0,0 @@
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/*
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* Copyright (c) 1993 Winning Strategies, Inc.
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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. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by Winning Strategies, Inc.
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* 4. The name of the author may not be used to endorse or promote products
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* derived from this software without 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 <machine/asm.h>
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__FBSDID("$FreeBSD$");
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/*
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* memchr (b, c, len)
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* locates the first occurrence of c in string b.
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*
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* Written by:
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* J.T. Conklin (jtc@wimsey.com), Winning Strategies, Inc.
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*/
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ENTRY(memchr)
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pushl %edi
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movl 8(%esp),%edi /* string address */
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movl 12(%esp),%eax /* set character to search for */
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movl 16(%esp),%ecx /* set length of search */
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testl %esp,%esp /* clear Z flag, for len == 0 */
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cld /* set search forward */
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repne /* search! */
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scasb
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jnz L1 /* scan failed, return null */
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leal -1(%edi),%eax /* adjust result of scan */
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popl %edi
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ret
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.align 2,0x90
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L1: xorl %eax,%eax
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popl %edi
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ret
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END(memchr)
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.section .note.GNU-stack,"",%progbits
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