usr/src/usr.bin/tn3270/general/vaxbsubs.s

/*
 * Copyright (c) 1988 Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms are permitted
 * provided that the above copyright notice and this paragraph are
 * duplicated in all such forms and that any documentation,
 * advertising materials, and other materials related to such
 * distribution and use acknowledge that the software was developed
 * by the University of California, Berkeley.  The name of the
 * University may not be used to endorse or promote products derived
 * from this software without specific prior written permission.
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 *
 *      @(#)vaxbsubs.s  1.3 (Berkeley) %G%
 */

/* This is taken from bcmp.s from 4.2.
 * The output of bunequal is the offset of the byte which didn't match;
 * if all the bytes match, then we return n.
 *
 * BUGNOTE:  This has no chance of working for lengths greater than 64K.
 *              (so, if you use this somewhere else, you may need to
 *              fix it...)
 */

/* bunequal(s1, s2, n) */

#include "defs.h"

ENTRY(bunequal)
        movl    4(ap),r1
        movl    8(ap),r3
        movl    12(ap),r4
1:
        movzwl  $65535,r0
        cmpl    r4,r0
        jleq    2f
        subl2   r0,r4
        cmpc3   r0,(r1),(r3)
        jeql    1b
        addl2   r4,r0
        /* changes... */
        subl3   r0,12(ap),r0
        /* end of changes for bunequal... */
        ret
2:
        cmpc3   r4,(r1),(r3)
        /* changes... */
        subl3   r0,12(ap),r0
        /* end of changes for bunequal... */
        ret


/* brand new code, using the above as base... */
/* bskip(s1, n, b) : finds the first occurrence of any byte != 'b' in the 'n'
 * bytes beginning at 's1'.
 *
 * BUGNOTE:  This has no chance of working for lengths greater than 64K.
 *              (so, if you use this somewhere else, you may need to
 *              fix it...)
 */

ENTRY(bskip)
        movl    4(ap),r1
        movl    8(ap),r3
        movl    12(ap),r4
1:
        movzwl  $65535,r0
        cmpl    r3,r0
        jleq    2f
        subl2   r0,r3
        skpc    r4,r0,(r1)
        jeql    1b
        addl2   r3,r0
        subl3   r0,8(ap),r0
        ret
2:
        skpc    r4,r3,(r1)
        subl3   r0,8(ap),r0
        ret