sysdeps/vax/bcopy.s

   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, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #if defined(LIBC_SCCS) && !defined(lint)
  35         .asciz "@(#)bcopy.s     5.6 (Berkeley) 6/1/90"
  36 #endif /* LIBC_SCCS and not lint */
  37
  38 /* bcopy(from, to, size) */
  39
  40 #include "DEFS.h"
  41
  42 ENTRY(bcopy, R6)
  43         movl    4(ap),r1
  44         movl    8(ap),r3
  45         movl    12(ap),r6
  46         cmpl    r1,r3
  47         bgtr    2f              # normal forward case
  48         blss    3f              # overlapping, must do backwards
  49         ret                     # equal, nothing to do
  50 1:
  51         subl2   r0,r6
  52         movc3   r0,(r1),(r3)
  53 2:
  54         movzwl  $65535,r0
  55         cmpl    r6,r0
  56         jgtr    1b
  57         movc3   r6,(r1),(r3)
  58         ret
  59 3:
  60         addl2   r6,r1
  61         addl2   r6,r3
  62         movzwl  $65535,r0
  63         jbr     5f
  64 4:
  65         subl2   r0,r6
  66         subl2   r0,r1
  67         subl2   r0,r3
  68         movc3   r0,(r1),(r3)
  69         movzwl  $65535,r0
  70         subl2   r0,r1
  71         subl2   r0,r3
  72 5:
  73         cmpl    r6,r0
  74         jgtr    4b
  75         subl2   r6,r1
  76         subl2   r6,r3
  77         movc3   r6,(r1),(r3)
  78         ret