/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2008 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
.file "wsncmp.s"
/
/ Wide character wcsncpy() implementation
/
/ Algorithm based on Solaris 2.6 gen/strncpy.s implementation
/
#include <sys/asm_linkage.h>
ANSI_PRAGMA_WEAK(wcsncmp,function)
ANSI_PRAGMA_WEAK(wsncmp,function)
ENTRY(wcsncmp) /* (wchar *ws1, wchar_t *ws2, size_t n) */
cmpq %rdi,%rsi / same string?
je .equal
incq %rdx / will later predecrement this uint
.loop:
decq %rdx
je .equal / Used all n chars?
movl (%rdi),%eax / slodb ; scab
cmpl (%rsi),%eax
jne .notequal_0 / Are the bytes equal?
testl %eax,%eax
je .equal / End of string?
decq %rdx
je .equal / Used all n chars?
movl 4(%rdi),%eax / slodb ; scab
cmpl 4(%rsi),%eax
jne .notequal_1 / Are the bytes equal?
testl %eax,%eax
je .equal / End of string?
decq %rdx
je .equal / Used all n chars?
movl 8(%rdi),%eax / slodb ; scab
cmpl 8(%rsi),%eax
jne .notequal_2 / Are the bytes equal?
testl %eax,%eax
je .equal / End of string?
decq %rdx
je .equal / Used all n chars?
movl 12(%rdi),%eax / slodb ; scab
cmpl 12(%rsi),%eax
jne .notequal_3 / Are the bytes equal?
addq $16,%rdi
addq $16,%rsi
testl %eax,%eax
jne .loop / End of string?
.equal:
xorl %eax,%eax / return 0
ret
.align 4
.notequal_3:
addq $4,%rsi
.notequal_2:
addq $4,%rsi
.notequal_1:
addq $4,%rsi
.notequal_0:
subl (%rsi),%eax / return value is (*s1 - *--s2)
ret
SET_SIZE(wcsncmp)
ENTRY(wsncmp)
jmp wcsncmp / tail call into wcsncmp
SET_SIZE(wsncmp)