17c478bd9Sstevel@tonic-gate/* 27c478bd9Sstevel@tonic-gate * CDDL HEADER START 37c478bd9Sstevel@tonic-gate * 47c478bd9Sstevel@tonic-gate * The contents of this file are subject to the terms of the 5*9a70fc3bSMark J. Nelson * Common Development and Distribution License (the "License"). 6*9a70fc3bSMark J. Nelson * You may not use this file except in compliance with the License. 77c478bd9Sstevel@tonic-gate * 87c478bd9Sstevel@tonic-gate * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 97c478bd9Sstevel@tonic-gate * or http://www.opensolaris.org/os/licensing. 107c478bd9Sstevel@tonic-gate * See the License for the specific language governing permissions 117c478bd9Sstevel@tonic-gate * and limitations under the License. 127c478bd9Sstevel@tonic-gate * 137c478bd9Sstevel@tonic-gate * When distributing Covered Code, include this CDDL HEADER in each 147c478bd9Sstevel@tonic-gate * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 157c478bd9Sstevel@tonic-gate * If applicable, add the following below this CDDL HEADER, with the 167c478bd9Sstevel@tonic-gate * fields enclosed by brackets "[]" replaced with your own identifying 177c478bd9Sstevel@tonic-gate * information: Portions Copyright [yyyy] [name of copyright owner] 187c478bd9Sstevel@tonic-gate * 197c478bd9Sstevel@tonic-gate * CDDL HEADER END 207c478bd9Sstevel@tonic-gate */ 217c478bd9Sstevel@tonic-gate/* 227c478bd9Sstevel@tonic-gate * Copyright 2005 Sun Microsystems, Inc. All rights reserved. 237c478bd9Sstevel@tonic-gate * Use is subject to license terms. 247c478bd9Sstevel@tonic-gate */ 257c478bd9Sstevel@tonic-gate 26*9a70fc3bSMark J. Nelson .file "strchr.s" 277c478bd9Sstevel@tonic-gate 287c478bd9Sstevel@tonic-gate#include "SYS.h" 297c478bd9Sstevel@tonic-gate 307c478bd9Sstevel@tonic-gate ENTRY(strchr) 317c478bd9Sstevel@tonic-gate mov 4(%esp), %ecx / src string here 327c478bd9Sstevel@tonic-gate mov 8(%esp), %edx / character to find 337c478bd9Sstevel@tonic-gate mov %ecx, %eax / save src 347c478bd9Sstevel@tonic-gate and $3, %ecx / check if src is aligned 357c478bd9Sstevel@tonic-gate jz prepword / search wordwise if it is 367c478bd9Sstevel@tonic-gate 377c478bd9Sstevel@tonic-gate cmpb %dl, (%eax) / src == char? 387c478bd9Sstevel@tonic-gate jz done 397c478bd9Sstevel@tonic-gate cmpb $0, (%eax) / src == 0? 407c478bd9Sstevel@tonic-gate jz not_found 417c478bd9Sstevel@tonic-gate add $1, %eax / increment src 427c478bd9Sstevel@tonic-gate cmp $3, %ecx / check alignment 437c478bd9Sstevel@tonic-gate jz prepword 447c478bd9Sstevel@tonic-gate cmpb %dl, (%eax) / src byte contains char? 457c478bd9Sstevel@tonic-gate jz done 467c478bd9Sstevel@tonic-gate cmpb $0, (%eax) / src byte == 0? 477c478bd9Sstevel@tonic-gate jz not_found 487c478bd9Sstevel@tonic-gate add $1, %eax / increment src ptr 497c478bd9Sstevel@tonic-gate cmp $2, %ecx / check alignment 507c478bd9Sstevel@tonic-gate jz prepword 517c478bd9Sstevel@tonic-gate cmpb %dl, (%eax) / check this byte 527c478bd9Sstevel@tonic-gate jz done 537c478bd9Sstevel@tonic-gate cmpb $0, (%eax) / is byte zero? 547c478bd9Sstevel@tonic-gate jz not_found 557c478bd9Sstevel@tonic-gate add $1, %eax / increment src ptr 567c478bd9Sstevel@tonic-gate 577c478bd9Sstevel@tonic-gateprepword: 587c478bd9Sstevel@tonic-gate push %ebx / save regs per calling convention 597c478bd9Sstevel@tonic-gate push %esi 607c478bd9Sstevel@tonic-gate and $0xff, %edx / only want 1st byte 617c478bd9Sstevel@tonic-gate mov %edx, %ebx / copy character across all bytes in wd 627c478bd9Sstevel@tonic-gate shl $8, %edx 637c478bd9Sstevel@tonic-gate or %ebx, %edx 647c478bd9Sstevel@tonic-gate mov %edx, %ebx 657c478bd9Sstevel@tonic-gate shl $16, %edx 667c478bd9Sstevel@tonic-gate or %ebx, %edx 677c478bd9Sstevel@tonic-gate 687c478bd9Sstevel@tonic-gate .align 16 / align loop for max performance 697c478bd9Sstevel@tonic-gate 707c478bd9Sstevel@tonic-gatesearchchar: 717c478bd9Sstevel@tonic-gate mov (%eax), %esi / load src word 727c478bd9Sstevel@tonic-gate add $4, %eax / increment src by four 737c478bd9Sstevel@tonic-gate mov %esi, %ebx / copy word 747c478bd9Sstevel@tonic-gate lea -0x01010101(%esi), %ecx / (word - 0x01010101) 757c478bd9Sstevel@tonic-gate xor %edx, %ebx / tmpword = word ^ char 767c478bd9Sstevel@tonic-gate not %esi / ~word 777c478bd9Sstevel@tonic-gate and $0x80808080, %esi / ~word & 0x80808080 787c478bd9Sstevel@tonic-gate and %ecx, %esi / (wd - 0x01010101) & ~wd & 0x80808080 797c478bd9Sstevel@tonic-gate jnz has_zero_byte 807c478bd9Sstevel@tonic-gate lea -0x01010101(%ebx), %ecx / repeat with tmpword 817c478bd9Sstevel@tonic-gate not %ebx 827c478bd9Sstevel@tonic-gate and $0x80808080, %ebx 837c478bd9Sstevel@tonic-gate and %ecx, %ebx 847c478bd9Sstevel@tonic-gate jz searchchar / repeat if char not found 857c478bd9Sstevel@tonic-gate 867c478bd9Sstevel@tonic-gatefound_char: 877c478bd9Sstevel@tonic-gate add $0x01010101, %ecx / restore tmpword 887c478bd9Sstevel@tonic-gate pop %esi / restore esi ebx as per calling cvntn 897c478bd9Sstevel@tonic-gate pop %ebx 907c478bd9Sstevel@tonic-gate test $0x000000ff, %ecx / look for character's position in word 917c478bd9Sstevel@tonic-gate jz done0 927c478bd9Sstevel@tonic-gate test $0x0000ff00, %ecx 937c478bd9Sstevel@tonic-gate jz done1 947c478bd9Sstevel@tonic-gate test $0x00ff0000, %ecx 957c478bd9Sstevel@tonic-gate jz done2 967c478bd9Sstevel@tonic-gatedone3: 977c478bd9Sstevel@tonic-gate sub $1, %eax 987c478bd9Sstevel@tonic-gate ret 997c478bd9Sstevel@tonic-gatedone2: 1007c478bd9Sstevel@tonic-gate sub $2, %eax 1017c478bd9Sstevel@tonic-gate ret 1027c478bd9Sstevel@tonic-gatedone1: 1037c478bd9Sstevel@tonic-gate sub $3, %eax 1047c478bd9Sstevel@tonic-gate ret 1057c478bd9Sstevel@tonic-gatedone0: 1067c478bd9Sstevel@tonic-gate sub $4, %eax 1077c478bd9Sstevel@tonic-gate ret 1087c478bd9Sstevel@tonic-gatehas_zero_byte: 1097c478bd9Sstevel@tonic-gate add $0x01010101, %ecx / restore registers here 1107c478bd9Sstevel@tonic-gate pop %esi 1117c478bd9Sstevel@tonic-gate pop %ebx 1127c478bd9Sstevel@tonic-gate cmpb %dl, %cl / check for character 1137c478bd9Sstevel@tonic-gate je done0 1147c478bd9Sstevel@tonic-gate testb %cl, %cl / check for null byte 1157c478bd9Sstevel@tonic-gate jz not_found 1167c478bd9Sstevel@tonic-gate cmpb %dh, %ch / continue checking for char, null 1177c478bd9Sstevel@tonic-gate je done1 1187c478bd9Sstevel@tonic-gate testb %ch, %ch 1197c478bd9Sstevel@tonic-gate jz not_found 1207c478bd9Sstevel@tonic-gate shr $16, %ecx / put bytes 2,3 into 8-but registers 1217c478bd9Sstevel@tonic-gate cmpb %dl, %cl 1227c478bd9Sstevel@tonic-gate je done2 1237c478bd9Sstevel@tonic-gate testb %cl, %cl 1247c478bd9Sstevel@tonic-gate jz not_found 1257c478bd9Sstevel@tonic-gate cmpb %dh, %ch / repeat checking last 2 bytes 1267c478bd9Sstevel@tonic-gate je done3 1277c478bd9Sstevel@tonic-gate testb %ch, %ch 1287c478bd9Sstevel@tonic-gate jz not_found 1297c478bd9Sstevel@tonic-gate sub $1, %eax / correct for last loop iteration 1307c478bd9Sstevel@tonic-gatedone: 1317c478bd9Sstevel@tonic-gate ret 1327c478bd9Sstevel@tonic-gatenot_found: 1337c478bd9Sstevel@tonic-gate xor %eax, %eax 1347c478bd9Sstevel@tonic-gate ret 1357c478bd9Sstevel@tonic-gate SET_SIZE(strchr) 136