1*0Sstevel@tonic-gate/* 2*0Sstevel@tonic-gate * CDDL HEADER START 3*0Sstevel@tonic-gate * 4*0Sstevel@tonic-gate * The contents of this file are subject to the terms of the 5*0Sstevel@tonic-gate * Common Development and Distribution License, Version 1.0 only 6*0Sstevel@tonic-gate * (the "License"). You may not use this file except in compliance 7*0Sstevel@tonic-gate * with the License. 8*0Sstevel@tonic-gate * 9*0Sstevel@tonic-gate * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10*0Sstevel@tonic-gate * or http://www.opensolaris.org/os/licensing. 11*0Sstevel@tonic-gate * See the License for the specific language governing permissions 12*0Sstevel@tonic-gate * and limitations under the License. 13*0Sstevel@tonic-gate * 14*0Sstevel@tonic-gate * When distributing Covered Code, include this CDDL HEADER in each 15*0Sstevel@tonic-gate * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16*0Sstevel@tonic-gate * If applicable, add the following below this CDDL HEADER, with the 17*0Sstevel@tonic-gate * fields enclosed by brackets "[]" replaced with your own identifying 18*0Sstevel@tonic-gate * information: Portions Copyright [yyyy] [name of copyright owner] 19*0Sstevel@tonic-gate * 20*0Sstevel@tonic-gate * CDDL HEADER END 21*0Sstevel@tonic-gate */ 22*0Sstevel@tonic-gate/* 23*0Sstevel@tonic-gate * Copyright 2003 Sun Microsystems, Inc. All rights reserved. 24*0Sstevel@tonic-gate * Use is subject to license terms. 25*0Sstevel@tonic-gate */ 26*0Sstevel@tonic-gate 27*0Sstevel@tonic-gate.ident "%Z%%M% %I% %E% SMI" 28*0Sstevel@tonic-gate 29*0Sstevel@tonic-gate .file "%M%" 30*0Sstevel@tonic-gate 31*0Sstevel@tonic-gate/* 32*0Sstevel@tonic-gate * The strchr() function returns a pointer to the first occurrence of c 33*0Sstevel@tonic-gate * (converted to a char) in string s, or a null pointer if c does not occur 34*0Sstevel@tonic-gate * in the string. 35*0Sstevel@tonic-gate */ 36*0Sstevel@tonic-gate 37*0Sstevel@tonic-gate#include <sys/asm_linkage.h> 38*0Sstevel@tonic-gate#include "synonyms.h" 39*0Sstevel@tonic-gate 40*0Sstevel@tonic-gate ! Here, we start by checking to see if we're searching the dest 41*0Sstevel@tonic-gate ! string for a null byte. We have fast code for this, so it's 42*0Sstevel@tonic-gate ! an important special case. Otherwise, if the string is not 43*0Sstevel@tonic-gate ! word aligned, we check a for the search char a byte at a time 44*0Sstevel@tonic-gate ! until we've reached a word boundary. Once this has happened 45*0Sstevel@tonic-gate ! some zero-byte finding values are initialized and the string 46*0Sstevel@tonic-gate ! is checked a word at a time 47*0Sstevel@tonic-gate 48*0Sstevel@tonic-gate ENTRY(strchr) 49*0Sstevel@tonic-gate 50*0Sstevel@tonic-gate .align 32 51*0Sstevel@tonic-gate 52*0Sstevel@tonic-gate andcc %o1, 0xff, %o1 ! search only for this one byte 53*0Sstevel@tonic-gate bz .searchnullbyte ! faster code for searching null 54*0Sstevel@tonic-gate andcc %o0, 3, %o4 ! str word aligned ? 55*0Sstevel@tonic-gate bz,a .prepword2 ! yup, prepare for word-wise search 56*0Sstevel@tonic-gate sll %o1, 8, %g1 ! start spreading findchar across word 57*0Sstevel@tonic-gate 58*0Sstevel@tonic-gate ldub [%o0], %o2 ! str[0] 59*0Sstevel@tonic-gate cmp %o2, %o1 ! str[0] == findchar ? 60*0Sstevel@tonic-gate be .done ! yup, done 61*0Sstevel@tonic-gate tst %o2 ! str[0] == 0 ? 62*0Sstevel@tonic-gate bz .notfound ! yup, return null pointer 63*0Sstevel@tonic-gate cmp %o4, 3 ! only one byte needed to align? 64*0Sstevel@tonic-gate bz .prepword ! yup, prepare for word-wise search 65*0Sstevel@tonic-gate inc %o0 ! str++ 66*0Sstevel@tonic-gate ldub [%o0], %o2 ! str[1] 67*0Sstevel@tonic-gate cmp %o2, %o1 ! str[1] == findchar ? 68*0Sstevel@tonic-gate be .done ! yup, done 69*0Sstevel@tonic-gate tst %o2 ! str[1] == 0 ? 70*0Sstevel@tonic-gate bz .notfound ! yup, return null pointer 71*0Sstevel@tonic-gate cmp %o4, 2 ! only two bytes needed to align? 72*0Sstevel@tonic-gate bz .prepword ! yup, prepare for word-wise search 73*0Sstevel@tonic-gate inc %o0 ! str++ 74*0Sstevel@tonic-gate ldub [%o0], %o2 ! str[2] 75*0Sstevel@tonic-gate cmp %o2, %o1 ! str[2] == findchar ? 76*0Sstevel@tonic-gate be .done ! yup, done 77*0Sstevel@tonic-gate tst %o2 ! str[2] == 0 ? 78*0Sstevel@tonic-gate bz .notfound ! yup, return null pointer 79*0Sstevel@tonic-gate inc %o0 ! str++ 80*0Sstevel@tonic-gate 81*0Sstevel@tonic-gate.prepword: 82*0Sstevel@tonic-gate sll %o1, 8, %g1 ! spread findchar ------+ 83*0Sstevel@tonic-gate.prepword2: ! 84*0Sstevel@tonic-gate sethi %hi(0x01010101), %o4 ! Alan Mycroft's magic1 ! 85*0Sstevel@tonic-gate or %o1, %g1, %o1 ! across all <---------+ 86*0Sstevel@tonic-gate sethi %hi(0x80808080), %o5 ! Alan Mycroft's magic2 ! 87*0Sstevel@tonic-gate sll %o1, 16, %g1 ! four bytes <--------+ 88*0Sstevel@tonic-gate or %o4, %lo(0x01010101), %o4 ! 89*0Sstevel@tonic-gate or %o1, %g1, %o1 ! of a word <--------+ 90*0Sstevel@tonic-gate or %o5, %lo(0x80808080), %o5 91*0Sstevel@tonic-gate 92*0Sstevel@tonic-gate.searchchar: 93*0Sstevel@tonic-gate lduw [%o0], %o2 ! src word 94*0Sstevel@tonic-gate andn %o5, %o2, %o3 ! ~word & 0x80808080 95*0Sstevel@tonic-gate sub %o2, %o4, %g1 ! word = (word - 0x01010101) 96*0Sstevel@tonic-gate andcc %o3, %g1, %g0 ! ((word - 0x01010101) & ~word & 0x80808080) 97*0Sstevel@tonic-gate bnz .haszerobyte ! zero byte if magic expression != 0 98*0Sstevel@tonic-gate xor %o2, %o1, %g1 ! tword = word ^ findchar 99*0Sstevel@tonic-gate andn %o5, %g1, %o3 ! ~tword & 0x80808080 100*0Sstevel@tonic-gate sub %g1, %o4, %o2 ! (tword - 0x01010101) 101*0Sstevel@tonic-gate andcc %o3, %o2, %g0 ! ((tword - 0x01010101) & ~tword & 0x80808080) 102*0Sstevel@tonic-gate bz,a .searchchar ! no findchar if magic expression == 0 103*0Sstevel@tonic-gate add %o0, 4, %o0 ! str += 4 104*0Sstevel@tonic-gate 105*0Sstevel@tonic-gate ! here we know "word" contains the searched character, but no null 106*0Sstevel@tonic-gate ! byte. if there was a null byte, we would have gone to .haszerobyte 107*0Sstevel@tonic-gate ! "tword" has null bytes where "word" had findchar. Examine "tword" 108*0Sstevel@tonic-gate 109*0Sstevel@tonic-gate.foundchar: 110*0Sstevel@tonic-gate set 0xff000000, %o4 ! mask for 1st byte 111*0Sstevel@tonic-gate andcc %g1, %o4, %g0 ! first byte zero (= found search char) ? 112*0Sstevel@tonic-gate bz .done ! yup, done 113*0Sstevel@tonic-gate set 0x00ff0000, %o5 ! mask for 2nd byte 114*0Sstevel@tonic-gate inc %o0 ! str++ 115*0Sstevel@tonic-gate andcc %g1, %o5, %g0 ! second byte zero (= found search char) ? 116*0Sstevel@tonic-gate bz .done ! yup, done 117*0Sstevel@tonic-gate srl %o4, 16, %o4 ! 0x0000ff00 = mask for 3rd byte 118*0Sstevel@tonic-gate inc %o0 ! str++ 119*0Sstevel@tonic-gate andcc %g1, %o4, %g0 ! third byte zero (= found search char) ? 120*0Sstevel@tonic-gate bnz,a .done ! nope, increment in delay slot 121*0Sstevel@tonic-gate inc %o0 ! str++ 122*0Sstevel@tonic-gate 123*0Sstevel@tonic-gate.done: 124*0Sstevel@tonic-gate retl ! done with leaf function 125*0Sstevel@tonic-gate nop ! padding 126*0Sstevel@tonic-gate 127*0Sstevel@tonic-gate ! Here we know that "word" contains a null byte indicating the 128*0Sstevel@tonic-gate ! end of the string. However, "word" might also contain findchar 129*0Sstevel@tonic-gate ! "tword" (in %g1) has null bytes where "word" had findchar. So 130*0Sstevel@tonic-gate ! check both "tword" and "word" 131*0Sstevel@tonic-gate 132*0Sstevel@tonic-gate.haszerobyte: 133*0Sstevel@tonic-gate set 0xff000000, %o4 ! mask for 1st byte 134*0Sstevel@tonic-gate andcc %g1, %o4, %g0 ! first byte == findchar ? 135*0Sstevel@tonic-gate bz .done ! yup, done 136*0Sstevel@tonic-gate andcc %o2, %o4, %g0 ! first byte == 0 ? 137*0Sstevel@tonic-gate bz .notfound ! yup, return null pointer 138*0Sstevel@tonic-gate set 0x00ff0000, %o4 ! mask for 2nd byte 139*0Sstevel@tonic-gate inc %o0 ! str++ 140*0Sstevel@tonic-gate andcc %g1, %o4, %g0 ! second byte == findchar ? 141*0Sstevel@tonic-gate bz .done ! yup, done 142*0Sstevel@tonic-gate andcc %o2, %o4, %g0 ! second byte == 0 ? 143*0Sstevel@tonic-gate bz .notfound ! yup, return null pointer 144*0Sstevel@tonic-gate srl %o4, 8, %o4 ! mask for 3rd byte = 0x0000ff00 145*0Sstevel@tonic-gate inc %o0 ! str++ 146*0Sstevel@tonic-gate andcc %g1, %o4, %g0 ! third byte == findchar ? 147*0Sstevel@tonic-gate bz .done ! yup, done 148*0Sstevel@tonic-gate andcc %o2, %o4, %g0 ! third byte == 0 ? 149*0Sstevel@tonic-gate bz .notfound ! yup, return null pointer 150*0Sstevel@tonic-gate andcc %g1, 0xff, %g0 ! fourth byte == findchar ? 151*0Sstevel@tonic-gate bz .done ! yup, done 152*0Sstevel@tonic-gate inc %o0 ! str++ 153*0Sstevel@tonic-gate 154*0Sstevel@tonic-gate.notfound: 155*0Sstevel@tonic-gate retl ! done with leaf function 156*0Sstevel@tonic-gate xor %o0, %o0, %o0 ! return null pointer 157*0Sstevel@tonic-gate 158*0Sstevel@tonic-gate ! since findchar == 0, we only have to do one test per item 159*0Sstevel@tonic-gate ! instead of two. This makes the search much faster. 160*0Sstevel@tonic-gate 161*0Sstevel@tonic-gate.searchnullbyte: 162*0Sstevel@tonic-gate bz .straligned ! str is word aligned 163*0Sstevel@tonic-gate nop ! padding 164*0Sstevel@tonic-gate 165*0Sstevel@tonic-gate cmp %o4, 2 ! str halfword aligned ? 166*0Sstevel@tonic-gate be .s2aligned ! yup 167*0Sstevel@tonic-gate ldub [%o0], %o1 ! str[0] 168*0Sstevel@tonic-gate tst %o1 ! byte zero? 169*0Sstevel@tonic-gate bz .done2 ! yup, done 170*0Sstevel@tonic-gate cmp %o4, 3 ! only one byte needed to align? 171*0Sstevel@tonic-gate bz .straligned ! yup 172*0Sstevel@tonic-gate inc %o0 ! str++ 173*0Sstevel@tonic-gate 174*0Sstevel@tonic-gate ! check to see if we're half word aligned, which it better than 175*0Sstevel@tonic-gate ! not being aligned at all. Search the first half of the word 176*0Sstevel@tonic-gate ! if we are, and then search by whole word. 177*0Sstevel@tonic-gate 178*0Sstevel@tonic-gate.s2aligned: 179*0Sstevel@tonic-gate lduh [%o0], %o1 ! str[] 180*0Sstevel@tonic-gate srl %o1, 8, %o4 ! %o4<7:0> = first byte 181*0Sstevel@tonic-gate tst %o4 ! first byte zero ? 182*0Sstevel@tonic-gate bz .done2 ! yup, done 183*0Sstevel@tonic-gate andcc %o1, 0xff, %g0 ! second byte zero ? 184*0Sstevel@tonic-gate bz,a .done2 ! yup, done 185*0Sstevel@tonic-gate inc %o0 ! str++ 186*0Sstevel@tonic-gate add %o0, 2, %o0 ! str+=2 187*0Sstevel@tonic-gate 188*0Sstevel@tonic-gate.straligned: 189*0Sstevel@tonic-gate sethi %hi(0x01010101), %o4 ! Alan Mycroft's magic1 190*0Sstevel@tonic-gate sethi %hi(0x80808080), %o5 ! Alan Mycroft's magic2 191*0Sstevel@tonic-gate or %o4, %lo(0x01010101), %o4 192*0Sstevel@tonic-gate or %o5, %lo(0x80808080), %o5 193*0Sstevel@tonic-gate 194*0Sstevel@tonic-gate.searchword: 195*0Sstevel@tonic-gate lduw [%o0], %o1 ! src word 196*0Sstevel@tonic-gate andn %o5, %o1, %o3 ! ~word & 0x80808080 197*0Sstevel@tonic-gate sub %o1, %o4, %g1 ! word = (word - 0x01010101) 198*0Sstevel@tonic-gate andcc %o3, %g1, %g0 ! ((word - 0x01010101) & ~word & 0x80808080) 199*0Sstevel@tonic-gate bz,a .searchword ! no zero byte if magic expression == 0 200*0Sstevel@tonic-gate add %o0, 4, %o0 ! str += 4 201*0Sstevel@tonic-gate 202*0Sstevel@tonic-gate.zerobyte: 203*0Sstevel@tonic-gate set 0xff000000, %o4 ! mask for 1st byte 204*0Sstevel@tonic-gate andcc %o1, %o4, %g0 ! first byte zero? 205*0Sstevel@tonic-gate bz .done2 ! yup, done 206*0Sstevel@tonic-gate set 0x00ff0000, %o5 ! mask for 2nd byte 207*0Sstevel@tonic-gate inc %o0 ! str++ 208*0Sstevel@tonic-gate andcc %o1, %o5, %g0 ! second byte zero? 209*0Sstevel@tonic-gate bz .done2 ! yup, done 210*0Sstevel@tonic-gate srl %o4, 16, %o4 ! 0x0000ff00 = mask for 3rd byte 211*0Sstevel@tonic-gate inc %o0 ! str++ 212*0Sstevel@tonic-gate andcc %o1, %o4, %g0 ! third byte zero? 213*0Sstevel@tonic-gate bnz,a .done2 ! nope, increment in delay slot 214*0Sstevel@tonic-gate inc %o0 ! str++ 215*0Sstevel@tonic-gate.done2: 216*0Sstevel@tonic-gate retl ! return from leaf function 217*0Sstevel@tonic-gate nop ! padding 218*0Sstevel@tonic-gate 219*0Sstevel@tonic-gate SET_SIZE(strchr) 220