mirror of
https://github.com/torvalds/linux.git
synced 2024-12-29 14:21:47 +00:00
4d1e7918aa
Optimise code to use efficient unaligned memory access which is available on ARCv2. This allows us to really simplify memcpy code and speed up the code one and a half times (in case of unaligned source or destination). Don't wire it up yet ! Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
48 lines
1009 B
ArmAsm
48 lines
1009 B
ArmAsm
/* SPDX-License-Identifier: GPL-2.0+ */
|
|
/*
|
|
* ARCv2 memcpy implementation optimized for unaligned memory access using.
|
|
*
|
|
* Copyright (C) 2019 Synopsys
|
|
* Author: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
|
|
*/
|
|
|
|
#include <linux/linkage.h>
|
|
|
|
#ifdef CONFIG_ARC_HAS_LL64
|
|
# define LOADX(DST,RX) ldd.ab DST, [RX, 8]
|
|
# define STOREX(SRC,RX) std.ab SRC, [RX, 8]
|
|
# define ZOLSHFT 5
|
|
# define ZOLAND 0x1F
|
|
#else
|
|
# define LOADX(DST,RX) ld.ab DST, [RX, 4]
|
|
# define STOREX(SRC,RX) st.ab SRC, [RX, 4]
|
|
# define ZOLSHFT 4
|
|
# define ZOLAND 0xF
|
|
#endif
|
|
|
|
ENTRY_CFI(memcpy)
|
|
mov r3, r0 ; don;t clobber ret val
|
|
|
|
lsr.f lp_count, r2, ZOLSHFT
|
|
lpnz @.Lcopy32_64bytes
|
|
;; LOOP START
|
|
LOADX (r6, r1)
|
|
LOADX (r8, r1)
|
|
LOADX (r10, r1)
|
|
LOADX (r4, r1)
|
|
STOREX (r6, r3)
|
|
STOREX (r8, r3)
|
|
STOREX (r10, r3)
|
|
STOREX (r4, r3)
|
|
.Lcopy32_64bytes:
|
|
|
|
and.f lp_count, r2, ZOLAND ;Last remaining 31 bytes
|
|
lpnz @.Lcopyremainingbytes
|
|
;; LOOP START
|
|
ldb.ab r5, [r1, 1]
|
|
stb.ab r5, [r3, 1]
|
|
.Lcopyremainingbytes:
|
|
|
|
j [blink]
|
|
END_CFI(memcpy)
|