wslen.s revision 2
2N/A/*
2N/A * CDDL HEADER START
2N/A *
2N/A * The contents of this file are subject to the terms of the
2N/A * Common Development and Distribution License (the "License").
2N/A * You may not use this file except in compliance with the License.
2N/A *
2N/A * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
2N/A * or http://www.opensolaris.org/os/licensing.
2N/A * See the License for the specific language governing permissions
2N/A * and limitations under the License.
2N/A *
2N/A * When distributing Covered Code, include this CDDL HEADER in each
2N/A * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
2N/A * If applicable, add the following below this CDDL HEADER, with the
2N/A * fields enclosed by brackets "[]" replaced with your own identifying
2N/A * information: Portions Copyright [yyyy] [name of copyright owner]
2N/A *
2N/A * CDDL HEADER END
2N/A */
2N/A
2N/A/*
2N/A * Copyright 2008 Sun Microsystems, Inc. All rights reserved.
2N/A * Use is subject to license terms.
2N/A */
2N/A
2N/A .file "wslen.s"
2N/A
2N/A/*
2N/A * Wide character wcslen() implementation
2N/A *
2N/A * size_t
2N/A * wcslen(const wchar_t *s)
2N/A *{
2N/A * const wchar_t *s0 = s + 1;
2N/A * while (*s++)
2N/A * ;
2N/A * return (s - s0);
2N/A *}
2N/A */
2N/A
2N/A#include <sys/asm_linkage.h>
2N/A
2N/A ANSI_PRAGMA_WEAK(wcslen,function)
2N/A ANSI_PRAGMA_WEAK(wslen,function)
2N/A
2N/A ENTRY(wcslen) /* (wchar_t *) */
2N/A xorl %eax,%eax
2N/A
2N/A .align 8
2N/A.loop:
2N/A cmpl $0,(%rdi)
2N/A je .out0
2N/A cmpl $0,4(%rdi)
2N/A je .out1
2N/A cmpl $0,8(%rdi)
2N/A je .out2
2N/A cmpl $0,12(%rdi)
2N/A je .out3
2N/A addq $4,%rax
2N/A addq $16,%rdi
2N/A jmp .loop
2N/A
2N/A .align 4
2N/A.out1:
2N/A incq %rax
2N/A.out0:
2N/A ret
2N/A
2N/A .align 4
2N/A.out2:
2N/A addq $2,%rax
2N/A ret
2N/A
2N/A .align 4
2N/A.out3:
2N/A addq $3, %rax
2N/A ret
2N/A SET_SIZE(wcslen)
2N/A
2N/A ENTRY(wslen)
2N/A jmp wcslen / tail call into wcslen
2N/A SET_SIZE(wslen)