mirror of
https://github.com/autc04/Retro68.git
synced 2024-11-05 04:06:45 +00:00
122 lines
3.9 KiB
ArmAsm
122 lines
3.9 KiB
ArmAsm
/*******************************************************************************
|
|
*
|
|
* Copyright (c) 1993 Intel Corporation
|
|
*
|
|
* Intel hereby grants you permission to copy, modify, and distribute this
|
|
* software and its documentation. Intel grants this permission provided
|
|
* that the above copyright notice appears in all copies and that both the
|
|
* copyright notice and this permission notice appear in supporting
|
|
* documentation. In addition, Intel grants this permission provided that
|
|
* you prominently mark as "not part of the original" any modifications
|
|
* made to this software or documentation, and that the name of Intel
|
|
* Corporation not be used in advertising or publicity pertaining to
|
|
* distribution of the software or the documentation without specific,
|
|
* written prior permission.
|
|
*
|
|
* Intel Corporation provides this AS IS, WITHOUT ANY WARRANTY, EXPRESS OR
|
|
* IMPLIED, INCLUDING, WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY
|
|
* OR FITNESS FOR A PARTICULAR PURPOSE. Intel makes no guarantee or
|
|
* representations regarding the use of, or the results of the use of,
|
|
* the software and documentation in terms of correctness, accuracy,
|
|
* reliability, currentness, or otherwise; and you rely on the software,
|
|
* documentation and results solely at your own risk.
|
|
*
|
|
* IN NO EVENT SHALL INTEL BE LIABLE FOR ANY LOSS OF USE, LOSS OF BUSINESS,
|
|
* LOSS OF PROFITS, INDIRECT, INCIDENTAL, SPECIAL OR CONSEQUENTIAL DAMAGES
|
|
* OF ANY KIND. IN NO EVENT SHALL INTEL'S TOTAL LIABILITY EXCEED THE SUM
|
|
* PAID TO INTEL FOR THE PRODUCT LICENSED HEREUNDER.
|
|
*
|
|
******************************************************************************/
|
|
|
|
.file "memset.s"
|
|
#ifdef __PIC
|
|
.pic
|
|
#endif
|
|
#ifdef __PID
|
|
.pid
|
|
#endif
|
|
/*
|
|
* (c) copyright 1989,1993 Intel Corp., all rights reserved
|
|
*/
|
|
|
|
/*
|
|
procedure memset (optimized assembler version: 80960K series, 80960CA)
|
|
|
|
dest_addr = memset (dest_addr, char, len)
|
|
|
|
Fill len bytes pointed to by dest_addr with the value of char.
|
|
Return the original address of dest_addr.
|
|
|
|
This program avoids performing unaligned accesses. It stores
|
|
from zero to seven bytes, and then stores aligned longwords,
|
|
and then stores from zero to seven bytes, as necessary to
|
|
store len bytes starting at dest_addr.
|
|
|
|
At the time of this writing, only g0 thru g7 and g13 are available
|
|
for use in this leafproc; other registers would have to be saved and
|
|
restored. These nine registers, plus tricky use of g14 are sufficient
|
|
to implement the routine.
|
|
*/
|
|
|
|
.globl _memset
|
|
.globl __memset
|
|
.leafproc _memset, __memset
|
|
.align 2
|
|
_memset:
|
|
#ifndef __PIC
|
|
lda Lrett,g14
|
|
#else
|
|
lda Lrett-(.+8)(ip),g14
|
|
#endif
|
|
__memset:
|
|
cmpo 7,g2 # are there fewer than seven characters to move?
|
|
lda (g14),g13 # save return address
|
|
notand g0,7,g3 # test for non-aligned dest_ptr
|
|
lda 0,g14 # conform to register conventions
|
|
shlo 24,g1,g4 # prepare word of char
|
|
lda (g0),g6 # preserve dest_ptr for return
|
|
shro 8,g4,g5
|
|
bge.f Lcloop_setup
|
|
cmpo g3,g0 # is dest longword aligned
|
|
lda 7(g3),g3 # bump dest_ptr to next longword boundary
|
|
or g4,g5,g4
|
|
be.t Lwloop_setup
|
|
|
|
Lbgn_cloop:
|
|
cmpo g6,g3 # Have we reached longword boundary?
|
|
stob g1,(g6) # store one byte of char
|
|
subo 1,g2,g2 # decrement len
|
|
lda 1(g6),g6 # increment dest_ptr
|
|
bne.t Lbgn_cloop # loop if more bytes to store before longword
|
|
|
|
cmpobge.f 7,g2,Lcloop
|
|
|
|
Lwloop_setup:
|
|
shro 16,g4,g5
|
|
or g4,g5,g4
|
|
mov g4,g5 # now have a longword of char
|
|
|
|
Lwloop:
|
|
cmpo 15,g2 # Do we have to store more longwords?
|
|
stl g4,(g6) # Store longword of char
|
|
subo 8,g2,g2 # Decrement len
|
|
lda 8(g6),g6 # Increment dest_ptr
|
|
bl.t Lwloop # loop if more longwords to store
|
|
|
|
Lcloop_setup:
|
|
cmpobge.t 0,g2,Lexit
|
|
|
|
Lcloop:
|
|
cmpo 1,g2 # Is len exhausted?
|
|
stob g1,(g6) # Store byte
|
|
subo 1,g2,g2 # Decrement len
|
|
lda 1(g6),g6 # Increment dest_ptr
|
|
bne.t Lcloop # loop if more bytes to store
|
|
|
|
Lexit:
|
|
bx (g13)
|
|
Lrett:
|
|
ret
|
|
|
|
/* end of memset */
|