1/* 2 * Copyright (c) 1983 Regents of the University of California. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms are permitted 6 * provided that the above copyright notice and this paragraph are 7 * duplicated in all such forms and that any documentation, 8 * advertising materials, and other materials related to such 9 * distribution and use acknowledge that the software was developed 10 * by the University of California, Berkeley. The name of the 11 * University may not be used to endorse or promote products derived 12 * from this software without specific prior written permission. 13 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR 14 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED 15 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. 16 */ 17 18#if defined(LIBC_SCCS) && !defined(lint) 19 .asciz "@(#)strcmp.s 5.5 (Berkeley) 06/27/88" 20#endif /* LIBC_SCCS and not lint */ 21 22/* 23 * Compare string s1 lexicographically to string s2. 24 * Return: 25 * 0 s1 == s2 26 * > 0 s1 > s2 27 * < 0 s2 < s2 28 * 29 * strcmp(s1, s2) 30 * char *s1, *s2; 31 */ 32#include "DEFS.h" 33 34ENTRY(strcmp, 0) 35 movl 4(ap),r1 # r1 = s1 36 movl 8(ap),r3 # r3 = s2 37 subb3 (r3),(r1),r0 # quick check for first char different 38 beql 1f # have to keep checking 39 cvtbl r0,r0 40 ret 411: 42 clrl r5 # calculate min bytes to next page boundry 43 subb3 r1,$255,r5 # r5 = (bytes - 1) to end of page for s1 44 subb3 r3,$255,r0 # r0 = (bytes - 1) to end of page for s2 45 cmpb r0,r5 # r5 = min(r0, r5); 46 bgtru 2f 47 movb r0,r5 482: 49 incl r5 # r5 = min bytes to next page boundry 50 cmpc3 r5,(r1),(r3) # compare strings 51 bneq 3f 52 subl2 r5,r1 # check if found null yet 53 locc $0,r5,(r1) 54 beql 1b # not yet done, continue checking 55 subl2 r0,r3 56 mnegb (r3),r0 # r0 = '\0' - *s2 57 cvtbl r0,r0 58 ret 593: 60 subl2 r0,r5 # check for null in matching string 61 subl2 r5,r1 62 locc $0,r5,(r1) 63 bneq 4f 64 subb3 (r3),(r1),r0 # r0 = *s1 - *s2 65 cvtbl r0,r0 66 ret 674: 68 clrl r0 # both the same to null 69 ret 70