mirror of
https://github.com/autc04/Retro68.git
synced 2024-12-11 19:49:32 +00:00
104 lines
3.2 KiB
ArmAsm
104 lines
3.2 KiB
ArmAsm
|
/*
|
||
|
|
Copyright (c) 2015, Synopsys, Inc. All rights reserved.
|
||
|
|
|
||
|
|
Redistribution and use in source and binary forms, with or without
|
||
|
|
modification, are permitted provided that the following conditions are met:
|
||
|
|
|
||
|
|
1) Redistributions of source code must retain the above copyright notice,
|
||
|
|
this list of conditions and the following disclaimer.
|
||
|
|
|
||
|
|
2) Redistributions in binary form must reproduce the above copyright notice,
|
||
|
|
this list of conditions and the following disclaimer in the documentation
|
||
|
|
and/or other materials provided with the distribution.
|
||
|
|
|
||
|
|
3) Neither the name of the Synopsys, Inc., nor the names of its contributors
|
||
|
|
may be used to endorse or promote products derived from this software
|
||
|
|
without specific prior written permission.
|
||
|
|
|
||
|
|
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
|
||
|
|
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
||
|
|
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
||
|
|
ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
|
||
|
|
LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
|
||
|
|
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
|
||
|
|
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
|
||
|
|
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
|
||
|
|
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
|
||
|
|
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
||
|
|
POSSIBILITY OF SUCH DAMAGE.
|
||
|
|
*/
|
||
|
|
|
||
|
|
/* This implementation is optimized for performance. For code size a generic
|
||
|
|
implementation of this function from newlib/libc/string/strcpy.c will be
|
||
|
|
used. */
|
||
|
|
#if !defined (__OPTIMIZE_SIZE__) && !defined (PREFER_SIZE_OVER_SPEED)
|
||
|
|
|
||
|
|
#include "asm.h"
|
||
|
|
|
||
|
|
#if (defined (__ARC700__) || defined (__ARCEM__) || defined (__ARCHS__)) \
|
||
|
|
&& defined (__ARC_BARREL_SHIFTER__)
|
||
|
|
|
||
|
|
/* If dst and src are 4 byte aligned, copy 8 bytes at a time.
|
||
|
|
If the src is 4, but not 8 byte aligned, we first read 4 bytes to get
|
||
|
|
it 8 byte aligned. Thus, we can do a little read-ahead, without
|
||
|
|
dereferencing a cache line that we should not touch.
|
||
|
|
Note that short and long instructions have been scheduled to avoid
|
||
|
|
branch stalls.
|
||
|
|
The beq_s to r3z could be made unaligned & long to avoid a stall
|
||
|
|
there, but the it is not likely to be taken often, and it
|
||
|
|
would also be likey to cost an unaligned mispredict at the next call. */
|
||
|
|
|
||
|
|
ENTRY (strcpy)
|
||
|
|
or r2,r0,r1
|
||
|
|
bmsk_s r2,r2,1
|
||
|
|
brne.d r2,0,charloop
|
||
|
|
mov_s r10,r0
|
||
|
|
ld_s r3,[r1,0]
|
||
|
|
mov r8,0x01010101
|
||
|
|
bbit0.d r1,2,loop_start
|
||
|
|
ror r12,r8
|
||
|
|
sub r2,r3,r8
|
||
|
|
bic_s r2,r2,r3
|
||
|
|
tst_s r2,r12
|
||
|
|
bne_l r3z
|
||
|
|
mov_s r4,r3
|
||
|
|
.balign 4
|
||
|
|
loop:
|
||
|
|
ld.a r3,[r1,4]
|
||
|
|
st.ab r4,[r10,4]
|
||
|
|
loop_start:
|
||
|
|
ld.a r4,[r1,4]
|
||
|
|
sub r2,r3,r8
|
||
|
|
bic_s r2,r2,r3
|
||
|
|
tst_l r2,r12
|
||
|
|
bne_l r3z
|
||
|
|
st.ab r3,[r10,4]
|
||
|
|
sub r2,r4,r8
|
||
|
|
bic r2,r2,r4
|
||
|
|
tst_l r2,r12
|
||
|
|
beq_l loop
|
||
|
|
mov_s r3,r4
|
||
|
|
#ifdef __LITTLE_ENDIAN__
|
||
|
|
r3z: bmsk.f r1,r3,7
|
||
|
|
lsr_s r3,r3,8
|
||
|
|
#else
|
||
|
|
r3z: lsr.f r1,r3,24
|
||
|
|
asl_s r3,r3,8
|
||
|
|
#endif
|
||
|
|
bne.d r3z
|
||
|
|
stb.ab r1,[r10,1]
|
||
|
|
j_s [blink]
|
||
|
|
|
||
|
|
.balign 4
|
||
|
|
charloop:
|
||
|
|
ldb.ab r3,[r1,1]
|
||
|
|
|
||
|
|
|
||
|
|
brne.d r3,0,charloop
|
||
|
|
stb.ab r3,[r10,1]
|
||
|
|
j [blink]
|
||
|
|
ENDFUNC (strcpy)
|
||
|
|
#endif /* (__ARC700__ || __ARCEM__ || __ARCHS__) && __ARC_BARREL_SHIFTER__ */
|
||
|
|
|
||
|
|
#endif /* !__OPTIMIZE_SIZE__ && !PREFER_SIZE_OVER_SPEED */
|