mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-06 02:50:43 +00:00
![Thomas Gleixner](/assets/img/avatar_default.png)
Based on 2 normalized pattern(s): 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 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 # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
67 lines
1.4 KiB
ArmAsm
67 lines
1.4 KiB
ArmAsm
/* SPDX-License-Identifier: GPL-2.0-only */
|
|
/*
|
|
* Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
|
|
*/
|
|
|
|
/* 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 <linux/linkage.h>
|
|
|
|
ENTRY_CFI(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
|
|
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_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
|
|
#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]
|
|
END_CFI(strcpy)
|