4.3BSD - /usr/src/lib/libc/vax/gen/bcopy.s

   1: /*
   2:  * Copyright (c) 1983 Regents of the University of California.
   3:  * All rights reserved.  The Berkeley software License Agreement
   4:  * specifies the terms and conditions for redistribution.
   5:  */
   6: 
   7: #ifdef LIBC_SCCS
   8:         .asciz  "@(#)bcopy.s	5.3 (Berkeley) 3/9/86"
   9: #endif LIBC_SCCS
  10: 
  11: /* bcopy(from, to, size) */
  12: 
  13: #include "DEFS.h"
  14: 
  15: ENTRY(bcopy, R6)
  16:         movl    4(ap),r1
  17:         movl    8(ap),r3
  18:         movl    12(ap),r6
  19:         cmpl    r1,r3
  20:         bgtr    2f              # normal forward case
  21:         blss    3f              # overlapping, must do backwards
  22:         ret                     # equal, nothing to do
  23: 1:
  24:         subl2   r0,r6
  25:         movc3   r0,(r1),(r3)
  26: 2:
  27:         movzwl  $65535,r0
  28:         cmpl    r6,r0
  29:         jgtr    1b
  30:         movc3   r6,(r1),(r3)
  31:         ret
  32: 3:
  33:         addl2   r6,r1
  34:         addl2   r6,r3
  35:         movzwl  $65535,r0
  36:         jbr     5f
  37: 4:
  38:         subl2   r0,r6
  39:         subl2   r0,r1
  40:         subl2   r0,r3
  41:         movc3   r0,(r1),(r3)
  42:         movzwl  $65535,r0
  43:         subl2   r0,r1
  44:         subl2   r0,r3
  45: 5:
  46:         cmpl    r6,r0
  47:         jgtr    4b
  48:         subl2   r6,r1
  49:         subl2   r6,r3
  50:         movc3   r6,(r1),(r3)
  51:         ret

Defined functions