blob: 318adb51ea169c59e9350f8e454b7bede780f97f [file] [log] [blame]
* Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
/* 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. */
#include <asm/linkage.h>
ARC_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 r3z
mov_s r4,r3
.balign 4
ld.a r3,[r1,4]
st.ab r4,[r10,4]
ld.a r4,[r1,4]
sub r2,r3,r8
bic_s r2,r2,r3
tst_s r2,r12
bne_s r3z
st.ab r3,[r10,4]
sub r2,r4,r8
bic r2,r2,r4
tst r2,r12
beq loop
mov_s r3,r4
r3z: bmsk.f r1,r3,7
lsr_s r3,r3,8
bne.d r3z
stb.ab r1,[r10,1]
j_s [blink]
.balign 4
ldb.ab r3,[r1,1]
brne.d r3,0,charloop
stb.ab r3,[r10,1]
j [blink]
ARC_EXIT strcpy