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aarch64: thunderx2 memmove performance improvements

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The performance improvement is about 20%-30% for
larger cases and about 1%-5% for smaller cases.

Used SIMD load/store instead of GPR for large
overlapping forward moves.

Reused existing memcpy implementation for smaller
or overlapping backward moves.

Fixed the existing memcpy implementation to allow it
to deal with the overlapping case.

Simplified loop tails in the memcpy implementation -
use branchless overlapping sequence of fixed length
load/stores instead of branching depending on the
size.

A cleanup/optimization converting str's to stp's.

Added __memmove_thunderx2 to the list of the
available implementations.
This commit is contained in:
Anton Youdkevitch 2019-05-03 11:01:34 -07:00 committed by Steve Ellcey
parent ac3da35de5
commit 32e902a94e
4 changed files with 226 additions and 361 deletions
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11
ChangeLog
View File

@ -1,3 +1,14 @@
2019-05-03 Anton Youdkevitch <anton.youdkevitch@bell-sw.com>
* sysdeps/aarch64/multiarch/ifunc-impl-list.c: Added
__memmove_thunderx2 to the list of implementations
* sysdeps/aarch64/multiarch/memmove.c: Likewise
* sysdeps/aarch64/multiarch/memcpy_thunderx2.S:
(__memmove_thunderx2): Rewritten using SIMD ld/st
(__memcpy_thunderx2): Fixed handling overlapping cases.
Used ldp/stp instead of ldr/str if possible. Made loops
tails branchless.
2019-05-03 Florian Weimer <fweimer@redhat.com>
* misc/tst-tsearch.c (walk_tree): Add more error checking.

1
sysdeps/aarch64/multiarch/ifunc-impl-list.c
View File

@ -45,6 +45,7 @@ __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
IFUNC_IMPL_ADD (array, i, memcpy, 1, __memcpy_generic))
IFUNC_IMPL (i, name, memmove,
IFUNC_IMPL_ADD (array, i, memmove, 1, __memmove_thunderx)
IFUNC_IMPL_ADD (array, i, memmove, 1, __memmove_thunderx2)
IFUNC_IMPL_ADD (array, i, memmove, 1, __memmove_falkor)
IFUNC_IMPL_ADD (array, i, memmove, 1, __memmove_generic))
IFUNC_IMPL (i, name, memset,

570
sysdeps/aarch64/multiarch/memcpy_thunderx2.S
View File

@ -31,8 +31,8 @@
#define dst x3
#define srcend x4
#define dstend x5
#define tmp2 x6
#define tmp3 x7
#define tmp2 x6
#define tmp3 x7
#define tmp3w w7
#define A_l x6
#define A_lw w6
@ -53,26 +53,26 @@
#define G_h dst
#define tmp1 x14
#define A_q q0
#define B_q q1
#define C_q q2
#define D_q q3
#define E_q q4
#define F_q q5
#define G_q q6
#define A_q q0
#define B_q q1
#define C_q q2
#define D_q q3
#define E_q q4
#define F_q q5
#define G_q q6
#define H_q q7
#define I_q q16
#define J_q q17
#define A_v v0
#define B_v v1
#define C_v v2
#define D_v v3
#define E_v v4
#define F_v v5
#define G_v v6
#define H_v v7
#define I_v v16
#define A_v v0
#define B_v v1
#define C_v v2
#define D_v v3
#define E_v v4
#define F_v v5
#define G_v v6
#define H_v v7
#define I_v v16
#define J_v v17
#ifndef MEMMOVE
@ -85,16 +85,14 @@
#if IS_IN (libc)
#undef MEMCPY
#undef MEMMOVE
#define MEMCPY __memcpy_thunderx2
#undef MEMMOVE
#define MEMMOVE __memmove_thunderx2
/* Moves are split into 3 main cases: small copies of up to 16 bytes,
medium copies of 17..96 bytes which are fully unrolled. Large copies
of more than 96 bytes align the destination and use an unrolled loop
processing 64 bytes per iteration.
Overlapping large forward memmoves use a loop that copies backwards.
/* Overlapping large forward memmoves use a loop that copies backwards.
Otherwise memcpy is used. Small moves branch to memcopy16 directly.
The longer memcpy cases fall through to the memcpy head.
*/
ENTRY_ALIGN (MEMMOVE, 6)
@ -103,188 +101,14 @@ ENTRY_ALIGN (MEMMOVE, 6)
DELOUSE (1)
DELOUSE (2)
add srcend, src, count
cmp count, 16
b.ls L(memcopy16)
sub tmp1, dstin, src
cmp count, 96
ccmp tmp1, count, 2, hi
b.lo L(move_long)
prfm PLDL1KEEP, [src]
add srcend, src, count
add dstend, dstin, count
cmp count, 16
b.ls L(copy16)
cmp count, 96
b.hi L(copy_long)
/* Medium copies: 17..96 bytes. */
sub tmp1, count, 1
ldp A_l, A_h, [src]
tbnz tmp1, 6, L(copy96)
ldp D_l, D_h, [srcend, -16]
tbz tmp1, 5, 1f
ldp B_l, B_h, [src, 16]
ldp C_l, C_h, [srcend, -32]
stp B_l, B_h, [dstin, 16]
stp C_l, C_h, [dstend, -32]
1:
stp A_l, A_h, [dstin]
stp D_l, D_h, [dstend, -16]
ret
.p2align 4
/* Small copies: 0..16 bytes. */
L(copy16):
cmp count, 8
b.lo 1f
ldr A_l, [src]
ldr A_h, [srcend, -8]
str A_l, [dstin]
str A_h, [dstend, -8]
ret
.p2align 4
1:
tbz count, 2, 1f
ldr A_lw, [src]
ldr A_hw, [srcend, -4]
str A_lw, [dstin]
str A_hw, [dstend, -4]
ret
/* Copy 0..3 bytes. Use a branchless sequence that copies the same
byte 3 times if count==1, or the 2nd byte twice if count==2. */
1:
cbz count, 2f
lsr tmp1, count, 1
ldrb A_lw, [src]
ldrb A_hw, [srcend, -1]
ldrb B_lw, [src, tmp1]
strb A_lw, [dstin]
strb B_lw, [dstin, tmp1]
strb A_hw, [dstend, -1]
2: ret
.p2align 4
/* Copy 64..96 bytes. Copy 64 bytes from the start and
32 bytes from the end. */
L(copy96):
ldp B_l, B_h, [src, 16]
ldp C_l, C_h, [src, 32]
ldp D_l, D_h, [src, 48]
ldp E_l, E_h, [srcend, -32]
ldp F_l, F_h, [srcend, -16]
stp A_l, A_h, [dstin]
stp B_l, B_h, [dstin, 16]
stp C_l, C_h, [dstin, 32]
stp D_l, D_h, [dstin, 48]
stp E_l, E_h, [dstend, -32]
stp F_l, F_h, [dstend, -16]
ret
/* Align DST to 16 byte alignment so that we don't cross cache line
boundaries on both loads and stores. There are at least 96 bytes
to copy, so copy 16 bytes unaligned and then align. The loop
copies 64 bytes per iteration and prefetches one iteration ahead. */
.p2align 4
L(copy_long):
and tmp1, dstin, 15
bic dst, dstin, 15
ldp D_l, D_h, [src]
sub src, src, tmp1
add count, count, tmp1 /* Count is now 16 too large. */
ldp A_l, A_h, [src, 16]
stp D_l, D_h, [dstin]
ldp B_l, B_h, [src, 32]
ldp C_l, C_h, [src, 48]
ldp D_l, D_h, [src, 64]!
subs count, count, 128 + 16 /* Test and readjust count. */
b.ls L(last64)
L(loop64):
stp A_l, A_h, [dst, 16]
ldp A_l, A_h, [src, 16]
stp B_l, B_h, [dst, 32]
ldp B_l, B_h, [src, 32]
stp C_l, C_h, [dst, 48]
ldp C_l, C_h, [src, 48]
stp D_l, D_h, [dst, 64]!
ldp D_l, D_h, [src, 64]!
subs count, count, 64
b.hi L(loop64)
/* Write the last full set of 64 bytes. The remainder is at most 64
bytes, so it is safe to always copy 64 bytes from the end even if
there is just 1 byte left. */
L(last64):
ldp E_l, E_h, [srcend, -64]
stp A_l, A_h, [dst, 16]
ldp A_l, A_h, [srcend, -48]
stp B_l, B_h, [dst, 32]
ldp B_l, B_h, [srcend, -32]
stp C_l, C_h, [dst, 48]
ldp C_l, C_h, [srcend, -16]
stp D_l, D_h, [dst, 64]
stp E_l, E_h, [dstend, -64]
stp A_l, A_h, [dstend, -48]
stp B_l, B_h, [dstend, -32]
stp C_l, C_h, [dstend, -16]
ret
.p2align 4
L(move_long):
cbz tmp1, 3f
add srcend, src, count
add dstend, dstin, count
/* Align dstend to 16 byte alignment so that we don't cross cache line
boundaries on both loads and stores. There are at least 96 bytes
to copy, so copy 16 bytes unaligned and then align. The loop
copies 64 bytes per iteration and prefetches one iteration ahead. */
and tmp1, dstend, 15
ldp D_l, D_h, [srcend, -16]
sub srcend, srcend, tmp1
sub count, count, tmp1
ldp A_l, A_h, [srcend, -16]
stp D_l, D_h, [dstend, -16]
ldp B_l, B_h, [srcend, -32]
ldp C_l, C_h, [srcend, -48]
ldp D_l, D_h, [srcend, -64]!
sub dstend, dstend, tmp1
subs count, count, 128
b.ls 2f
nop
1:
stp A_l, A_h, [dstend, -16]
ldp A_l, A_h, [srcend, -16]
stp B_l, B_h, [dstend, -32]
ldp B_l, B_h, [srcend, -32]
stp C_l, C_h, [dstend, -48]
ldp C_l, C_h, [srcend, -48]
stp D_l, D_h, [dstend, -64]!
ldp D_l, D_h, [srcend, -64]!
subs count, count, 64
b.hi 1b
/* Write the last full set of 64 bytes. The remainder is at most 64
bytes, so it is safe to always copy 64 bytes from the start even if
there is just 1 byte left. */
2:
ldp G_l, G_h, [src, 48]
stp A_l, A_h, [dstend, -16]
ldp A_l, A_h, [src, 32]
stp B_l, B_h, [dstend, -32]
ldp B_l, B_h, [src, 16]
stp C_l, C_h, [dstend, -48]
ldp C_l, C_h, [src]
stp D_l, D_h, [dstend, -64]
stp G_l, G_h, [dstin, 48]
stp A_l, A_h, [dstin, 32]
stp B_l, B_h, [dstin, 16]
stp C_l, C_h, [dstin]
3: ret
END (MEMMOVE)
libc_hidden_builtin_def (MEMMOVE)
@ -293,227 +117,217 @@ libc_hidden_builtin_def (MEMMOVE)
medium copies of 17..96 bytes which are fully unrolled. Large copies
of more than 96 bytes align the destination and use load-and-merge
approach in the case src and dst addresses are unaligned not evenly,
so that, loads and stores are always aligned.
Large copies use an unrolled loop processing 64 bytes per iteration.
The current optimized memcpy implementation is not compatible with
memmove and is separated from it completely.
memcpy implementation below is not compatible with memmove
because of pipelined loads/stores, which are faster, but they
can't be used in the case of overlapping memmove arrays */
so that, actual loads and stores are always aligned.
Large copies use the loops processing 64 bytes per iteration for
unaligned case and 128 bytes per iteration for aligned ones.
*/
#define MEMCPY_PREFETCH_LDR 640
.p2align 4
ENTRY (MEMCPY)
DELOUSE (0)
DELOUSE (1)
DELOUSE (2)
add srcend, src, count
cmp count, 16
b.ls L(memcopy16)
ldr A_q, [src], #16
add dstend, dstin, count
and tmp1, src, 15
cmp count, 96
b.hi L(memcopy_long)
add srcend, src, count
cmp count, 16
b.ls L(memcopy16)
ldr A_q, [src], #16
add dstend, dstin, count
and tmp1, src, 15
cmp count, 96
b.hi L(memcopy_long)
/* Medium copies: 17..96 bytes. */
ldr E_q, [srcend, -16]
cmp count, 64
b.gt L(memcpy_copy96)
cmp count, 48
b.le L(bytes_17_to_48)
ldr E_q, [srcend, -16]
cmp count, 64
b.gt L(memcpy_copy96)
cmp count, 48
b.le L(bytes_17_to_48)
/* 49..64 bytes */
ldp B_q, C_q, [src]
str E_q, [dstend, -16]
stp A_q, B_q, [dstin]
str C_q, [dstin, 32]
ldp B_q, C_q, [src]
str E_q, [dstend, -16]
stp A_q, B_q, [dstin]
str C_q, [dstin, 32]
ret
L(bytes_17_to_48):
/* 17..48 bytes*/
cmp count, 32
b.gt L(bytes_32_to_48)
cmp count, 32
b.gt L(bytes_32_to_48)
/* 17..32 bytes*/
str A_q, [dstin]
str E_q, [dstend, -16]
str A_q, [dstin]
str E_q, [dstend, -16]
ret
L(bytes_32_to_48):
/* 32..48 */
ldr B_q, [src]
str A_q, [dstin]
str E_q, [dstend, -16]
str B_q, [dstin, 16]
ldr B_q, [src]
str A_q, [dstin]
str E_q, [dstend, -16]
str B_q, [dstin, 16]
ret
.p2align 4
/* Small copies: 0..16 bytes. */
L(memcopy16):
cmp count, 8
b.lo L(bytes_0_to_8)
ldr A_l, [src]
ldr A_h, [srcend, -8]
add dstend, dstin, count
str A_l, [dstin]
str A_h, [dstend, -8]
cmp count, 8
b.lo L(bytes_0_to_8)
ldr A_l, [src]
ldr A_h, [srcend, -8]
add dstend, dstin, count
str A_l, [dstin]
str A_h, [dstend, -8]
ret
.p2align 4
L(bytes_0_to_8):
tbz count, 2, L(bytes_0_to_3)
ldr A_lw, [src]
ldr A_hw, [srcend, -4]
add dstend, dstin, count
str A_lw, [dstin]
str A_hw, [dstend, -4]
tbz count, 2, L(bytes_0_to_3)
ldr A_lw, [src]
ldr A_hw, [srcend, -4]
add dstend, dstin, count
str A_lw, [dstin]
str A_hw, [dstend, -4]
ret
/* Copy 0..3 bytes. Use a branchless sequence that copies the same
byte 3 times if count==1, or the 2nd byte twice if count==2. */
L(bytes_0_to_3):
cbz count, L(end)
lsr tmp1, count, 1
ldrb A_lw, [src]
ldrb A_hw, [srcend, -1]
add dstend, dstin, count
ldrb B_lw, [src, tmp1]
strb A_lw, [dstin]
strb B_lw, [dstin, tmp1]
strb A_hw, [dstend, -1]
L(end):
cbz count, 1f
lsr tmp1, count, 1
ldrb A_lw, [src]
ldrb A_hw, [srcend, -1]
add dstend, dstin, count
ldrb B_lw, [src, tmp1]
strb B_lw, [dstin, tmp1]
strb A_hw, [dstend, -1]
strb A_lw, [dstin]
1:
ret
.p2align 4
L(memcpy_copy96):
/* Copying 65..96 bytes. A_q (first 16 bytes) and
E_q(last 16 bytes) are already loaded.
The size is large enough to benefit from aligned
loads */
bic src, src, 15
ldp B_q, C_q, [src]
str A_q, [dstin]
E_q(last 16 bytes) are already loaded. The size
is large enough to benefit from aligned loads */
bic src, src, 15
ldp B_q, C_q, [src]
/* Loaded 64 bytes, second 16-bytes chunk can be
overlapping with the first chunk by tmp1 bytes.
Stored 16 bytes. */
sub dst, dstin, tmp1
add count, count, tmp1
sub dst, dstin, tmp1
add count, count, tmp1
/* The range of count being [65..96] becomes [65..111]
after tmp [0..15] gets added to it,
count now is <bytes-left-to-load>+48 */
cmp count, 80
b.gt L(copy96_medium)
ldr D_q, [src, 32]
stp B_q, C_q, [dst, 16]
str E_q, [dstend, -16]
str D_q, [dst, 48]
cmp count, 80
b.gt L(copy96_medium)
ldr D_q, [src, 32]
stp B_q, C_q, [dst, 16]
str D_q, [dst, 48]
str A_q, [dstin]
str E_q, [dstend, -16]
ret
.p2align 4
L(copy96_medium):
ldp D_q, A_q, [src, 32]
str B_q, [dst, 16]
cmp count, 96
b.gt L(copy96_large)
str E_q, [dstend, -16]
stp C_q, D_q, [dst, 32]
str A_q, [dst, 64]
ldp D_q, G_q, [src, 32]
cmp count, 96
b.gt L(copy96_large)
stp B_q, C_q, [dst, 16]
stp D_q, G_q, [dst, 48]
str A_q, [dstin]
str E_q, [dstend, -16]
ret
L(copy96_large):
ldr F_q, [src, 64]
stp C_q, D_q, [dst, 32]
str E_q, [dstend, -16]
stp A_q, F_q, [dst, 64]
ldr F_q, [src, 64]
str B_q, [dst, 16]
stp C_q, D_q, [dst, 32]
stp G_q, F_q, [dst, 64]
str A_q, [dstin]
str E_q, [dstend, -16]
ret
.p2align 4
L(memcopy_long):
bic src, src, 15
ldp B_q, C_q, [src], #32
str A_q, [dstin]
sub dst, dstin, tmp1
add count, count, tmp1
add dst, dst, 16
bic src, src, 15
ldp B_q, C_q, [src], #32
sub dst, dstin, tmp1
add count, count, tmp1
add dst, dst, 16
and tmp1, dst, 15
ldp D_q, E_q, [src], #32
str B_q, [dst], #16
ldp D_q, E_q, [src], #32
str A_q, [dstin]
/* Already loaded 64+16 bytes. Check if at
least 64 more bytes left */
subs count, count, 64+64+16
b.lt L(loop128_exit2)
cmp count, MEMCPY_PREFETCH_LDR + 64 + 32
b.lt L(loop128)
subs count, count, 64+64+16
b.lt L(loop128_exit0)
cmp count, MEMCPY_PREFETCH_LDR + 64 + 32
b.lt L(loop128)
cbnz tmp1, L(dst_unaligned)
sub count, count, MEMCPY_PREFETCH_LDR + 64 + 32
sub count, count, MEMCPY_PREFETCH_LDR + 64 + 32
.p2align 4
L(loop128_prefetch):
str C_q, [dst], #16
prfm pldl1strm, [src, MEMCPY_PREFETCH_LDR]
str D_q, [dst], #16
ldp F_q, G_q, [src], #32
str E_q, [dst], #16
ldp H_q, A_q, [src], #32
str F_q, [dst], #16
prfm pldl1strm, [src, MEMCPY_PREFETCH_LDR]
str G_q, [dst], #16
ldp B_q, C_q, [src], #32
str H_q, [dst], #16
ldp D_q, E_q, [src], #32
stp A_q, B_q, [dst], #32
prfm pldl1strm, [src, MEMCPY_PREFETCH_LDR]
ldp F_q, G_q, [src], #32
stp B_q, C_q, [dst], #32
ldp H_q, I_q, [src], #32
prfm pldl1strm, [src, MEMCPY_PREFETCH_LDR]
ldp B_q, C_q, [src], #32
stp D_q, E_q, [dst], #32
ldp D_q, E_q, [src], #32
stp F_q, G_q, [dst], #32
stp H_q, I_q, [dst], #32
subs count, count, 128
b.ge L(loop128_prefetch)
b.ge L(loop128_prefetch)
L(preloop128):
add count, count, MEMCPY_PREFETCH_LDR + 64 + 32
.p2align 4
L(loop128):
ldp F_q, G_q, [src], #32
str C_q, [dst], #16
ldp B_q, A_q, [src], #32
str D_q, [dst], #16
stp E_q, F_q, [dst], #32
stp G_q, B_q, [dst], #32
subs count, count, 64
b.lt L(loop128_exit1)
L(loop128_proceed):
ldp B_q, C_q, [src], #32
str A_q, [dst], #16
ldp D_q, E_q, [src], #32
str B_q, [dst], #16
subs count, count, 64
b.ge L(loop128)
.p2align 4
L(loop128_exit2):
stp C_q, D_q, [dst], #32
str E_q, [dst], #16
b L(copy_long_check32);
ldp F_q, G_q, [src], #32
ldp H_q, I_q, [src], #32
stp B_q, C_q, [dst], #32
stp D_q, E_q, [dst], #32
subs count, count, 64
b.lt L(loop128_exit1)
ldp B_q, C_q, [src], #32
ldp D_q, E_q, [src], #32
stp F_q, G_q, [dst], #32
stp H_q, I_q, [dst], #32
subs count, count, 64
b.ge L(loop128)
L(loop128_exit0):
ldp F_q, G_q, [srcend, -64]
ldp H_q, I_q, [srcend, -32]
stp B_q, C_q, [dst], #32
stp D_q, E_q, [dst]
stp F_q, G_q, [dstend, -64]
stp H_q, I_q, [dstend, -32]
ret
L(loop128_exit1):
/* A_q is still not stored and 0..63 bytes left,
so, count is -64..-1.
Check if less than 32 bytes left (count < -32) */
str A_q, [dst], #16
L(copy_long_check32):
cmn count, 64
b.eq L(copy_long_done)
cmn count, 32
b.le L(copy_long_last32)
ldp B_q, C_q, [src]
stp B_q, C_q, [dst]
ldp B_q, C_q, [srcend, -64]
ldp D_q, E_q, [srcend, -32]
stp F_q, G_q, [dst], #32
stp H_q, I_q, [dst]
stp B_q, C_q, [dstend, -64]
stp D_q, E_q, [dstend, -32]
ret
L(copy_long_last32):
ldp F_q, G_q, [srcend, -32]
stp F_q, G_q, [dstend, -32]
L(copy_long_done):
L(dst_unaligned_tail):
ldp C_q, D_q, [srcend, -64]
ldp E_q, F_q, [srcend, -32]
stp A_q, B_q, [dst], #32
stp H_q, I_q, [dst], #16
str G_q, [dst, tmp1]
stp C_q, D_q, [dstend, -64]
stp E_q, F_q, [dstend, -32]
ret
L(dst_unaligned):
@ -542,17 +356,20 @@ L(dst_unaligned):
/* Store the 16 bytes to dst and align dst for further
operations, several bytes will be stored at this
address once more */
str C_q, [dst], #16
ldp F_q, G_q, [src], #32
ldp F_q, G_q, [src], #32
stp B_q, C_q, [dst], #32
bic dst, dst, 15
subs count, count, 32
sub count, count, 32
adrp tmp2, L(ext_table)
add tmp2, tmp2, :lo12:L(ext_table)
add tmp2, tmp2, tmp1, LSL #2
ldr tmp3w, [tmp2]
add tmp2, tmp2, tmp3w, SXTW
br tmp2
.p2align 4 ;\
.p2align 4
/* to make the loop in each chunk 16-bytes aligned */
nop
#define EXT_CHUNK(shft) \
L(ext_size_ ## shft):;\
@ -573,7 +390,7 @@ L(ext_size_ ## shft):;\
b.ge 1b;\
2:;\
ext I_v.16b, F_v.16b, G_v.16b, 16-shft;\
b L(ext_tail);
b L(dst_unaligned_tail);
EXT_CHUNK(1)
EXT_CHUNK(2)
@ -591,12 +408,45 @@ EXT_CHUNK(13)
EXT_CHUNK(14)
EXT_CHUNK(15)
L(ext_tail):
stp A_q, B_q, [dst], #32
stp H_q, I_q, [dst], #16
add dst, dst, tmp1
str G_q, [dst], #16
b L(copy_long_check32)
L(move_long):
.p2align 4
1:
cbz tmp1, 3f
add srcend, src, count
add dstend, dstin, count
and tmp1, srcend, 15
ldr D_q, [srcend, -16]
sub srcend, srcend, tmp1
sub count, count, tmp1
ldp A_q, B_q, [srcend, -32]
str D_q, [dstend, -16]
ldp C_q, D_q, [srcend, -64]!
sub dstend, dstend, tmp1
subs count, count, 128
b.ls 2f
.p2align 4
1:
subs count, count, 64
stp A_q, B_q, [dstend, -32]
ldp A_q, B_q, [srcend, -32]
stp C_q, D_q, [dstend, -64]!
ldp C_q, D_q, [srcend, -64]!
b.hi 1b
/* Write the last full set of 64 bytes. The remainder is at most 64
bytes, so it is safe to always copy 64 bytes from the start even if
there is just 1 byte left. */
2:
ldp E_q, F_q, [src, 32]
ldp G_q, H_q, [src]
stp A_q, B_q, [dstend, -32]
stp C_q, D_q, [dstend, -64]
stp E_q, F_q, [dstin, 32]
stp G_q, H_q, [dstin]
3: ret
END (MEMCPY)

5
sysdeps/aarch64/multiarch/memmove.c
View File

@ -30,6 +30,7 @@ extern __typeof (__redirect_memmove) __libc_memmove;
extern __typeof (__redirect_memmove) __memmove_generic attribute_hidden;
extern __typeof (__redirect_memmove) __memmove_thunderx attribute_hidden;
extern __typeof (__redirect_memmove) __memmove_thunderx2 attribute_hidden;
extern __typeof (__redirect_memmove) __memmove_falkor attribute_hidden;
libc_ifunc (__libc_memmove,
@ -37,7 +38,9 @@ libc_ifunc (__libc_memmove,
? __memmove_thunderx
: (IS_FALKOR (midr) || IS_PHECDA (midr)
? __memmove_falkor
: __memmove_generic)));
: (IS_THUNDERX2 (midr) || IS_THUNDERX2PA (midr)
? __memmove_thunderx2
: __memmove_generic))));
# undef memmove
strong_alias (__libc_memmove, memmove);