strrchr.s revision 9a70fc3be3b1e966bf78825cdb8d509963a6f0a1
/*
* 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
* 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 2004 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
/
/
/
/
/ char *
/ strrchr(const char *sp, int c)
/ {
/ char *r = NULL;
/
/ do {
/ if (*sp == (char)c)
/ r = (char *)sp;
/ } while (*sp++);
/
/ return (r);
/ }
/
#include "SYS.h"
ENTRY(strrchr) /* (char *s, int c) */
movl $0, %eax / %rax = NULL (current occurrence)
movl %esi, %ecx / %cl == char to search for
testq $3, %rdi / if %rdi not word aligned
jnz .L1 / goto .L1
.align 4
.L3:
movl (%rdi), %edx / move 1 word from (%rdi) to %edx
cmpb %cl, %dl / if the fist byte is not %cl
jne .L4 / goto .L4
movq %rdi, %rax / save this address to %rax
.L4:
cmpb $0, %dl / if a null termination
je .L8 / goto .L8
cmpb %cl, %dh / if the second byte is not %cl
jne .L5 / goto .L5
leaq 1(%rdi), %rax / save this address to %rax
.L5:
cmpb $0, %dh / if a null termination
je .L8 / goto .L8
shrl $16, %edx / right shift 16-bit
cmpb %cl, %dl / if the third byte is not %cl
jne .L6 / goto .L6
leaq 2(%rdi), %rax / save this address to %rax
.L6:
cmpb $0, %dl / if a null termination
je .L8 / goto .L8
cmpb %cl, %dh / if the fourth byte is not %cl
jne .L7 / goto .L7
leaq 3(%rdi), %rax / save this address to %rax
.L7:
cmpb $0, %dh / if a null termination
je .L8 / goto .L8
addq $4, %rdi / next word
jmp .L3 / goto .L3
.align 4
.L1:
movb (%rdi), %dl / move 1 byte from (%rdi) to %dl
cmpb %cl, %dl / if %dl is not %cl
jne .L2 / goto .L2
movq %rdi, %rax / save this address to %rax
.L2:
cmpb $0, %dl / if a null termination
je .L8 / goto .L8
incq %rdi / next byte
testq $3, %rdi / if %rdi not word aligned
jnz .L1 / goto .L1
jmp .L3 / goto .L3 (word aligned)
.align 4
.L8:
ret / %rax points to the last occurrence or NULL
SET_SIZE(strrchr)