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Make both stpcpy and strcpy be assembly language implementations

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on amd64.

Submitted by:	Guillaume Morin (guillaume at morinfr.org)
Reviewed by:	kib, jhb
Approved by:	re (bz)
MFC after:	1 month
This commit is contained in:
George V. Neville-Neil 2011-07-21 16:32:13 +00:00
parent f51c84eaf6
commit c03b5ad6a9
3 changed files with 60 additions and 20 deletions
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2
lib/libc/amd64/string/Makefile.inc
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@ -1,4 +1,4 @@
# $FreeBSD$
MDSRCS+= bcmp.S bcopy.S bzero.S memcmp.S memcpy.S memmove.S memset.S \
strcat.S strcmp.S strcpy.S
strcat.S strcmp.S stpcpy.S strcpy.c

40
lib/libc/amd64/string/strcpy.S → lib/libc/amd64/string/stpcpy.S
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@ -1,17 +1,14 @@
/*
* Written by J.T. Conklin <jtc@acorntoolworks.com>
* Adapted by Guillaume Morin <guillaume@hudson-trading.com> from strcpy.S
* written by J.T. Conklin <jtc@acorntoolworks.com>
* Public domain.
*/
#include <machine/asm.h>
__FBSDID("$FreeBSD$");
#if 0
RCSID("$NetBSD: strcpy.S,v 1.3 2004/07/19 20:04:41 drochner Exp $")
#endif
/*
* This strcpy implementation copies a byte at a time until the
* This stpcpy implementation copies a byte at a time until the
* source pointer is aligned to a word boundary, it then copies by
* words until it finds a word containing a zero byte, and finally
* copies by bytes until the end of the string is reached.
@ -23,10 +20,11 @@ __FBSDID("$FreeBSD$");
* requirements.
*/
ENTRY(strcpy)
movq %rdi,%rax
movabsq $0x0101010101010101,%r8
movabsq $0x8080808080808080,%r9
.globl stpcpy,__stpcpy
ENTRY(stpcpy)
__stpcpy:
movabsq $0x0101010101010101,%r8
movabsq $0x8080808080808080,%r9
/*
* Align source to a word boundary.
@ -41,6 +39,8 @@ ENTRY(strcpy)
incq %rdi
testb %dl,%dl
jne .Lalign
movq %rdi,%rax
dec %rax
ret
.p2align 4
@ -61,54 +61,56 @@ ENTRY(strcpy)
*/
movb %dl,(%rdi)
incq %rdi
testb %dl,%dl /* 1st byte == 0? */
je .Ldone
incq %rdi
shrq $8,%rdx
movb %dl,(%rdi)
incq %rdi
testb %dl,%dl /* 2nd byte == 0? */
je .Ldone
incq %rdi
shrq $8,%rdx
movb %dl,(%rdi)
incq %rdi
testb %dl,%dl /* 3rd byte == 0? */
je .Ldone
incq %rdi
shrq $8,%rdx
movb %dl,(%rdi)
incq %rdi
testb %dl,%dl /* 4th byte == 0? */
je .Ldone
incq %rdi
shrq $8,%rdx
movb %dl,(%rdi)
incq %rdi
testb %dl,%dl /* 5th byte == 0? */
je .Ldone
incq %rdi
shrq $8,%rdx
movb %dl,(%rdi)
incq %rdi
testb %dl,%dl /* 6th byte == 0? */
je .Ldone
incq %rdi
shrq $8,%rdx
movb %dl,(%rdi)
incq %rdi
testb %dl,%dl /* 7th byte == 0? */
je .Ldone
incq %rdi
shrq $8,%rdx
movb %dl,(%rdi)
incq %rdi
testb %dl,%dl /* 8th byte == 0? */
jne .Lword_aligned
decq %rdi
.Ldone:
movq %rdi,%rax
ret
END(strcpy)
END(stpcpy)
.section .note.GNU-stack,"",%progbits

38
lib/libc/amd64/string/strcpy.c Normal file
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@ -0,0 +1,38 @@
/*
* Copyright 2011 George V. Neville-Neil. All rights reserved.
*
* The compilation of software known as FreeBSD is distributed under the
* following terms:
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
char *__stpcpy(char * __restrict, const char * __restrict);
char *
strcpy(char * __restrict to, const char * __restrict from)
{
__stpcpy(to, from);
return(to);
}