mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-30 08:40:07 +00:00
196 lines
4.2 KiB
ArmAsm
196 lines
4.2 KiB
ArmAsm
/* Copyright (C) 2012-2017 Free Software Foundation, Inc.
|
|
|
|
This file is part of the GNU C Library.
|
|
|
|
The GNU C Library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Lesser General Public
|
|
License as published by the Free Software Foundation; either
|
|
version 2.1 of the License, or (at your option) any later version.
|
|
|
|
The GNU C Library is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public
|
|
License along with the GNU C Library. If not, see
|
|
<http://www.gnu.org/licenses/>. */
|
|
|
|
#include <sysdep.h>
|
|
|
|
/* Assumptions:
|
|
*
|
|
* ARMv8-a, AArch64, unaligned accesses
|
|
*
|
|
*/
|
|
|
|
#define dstin x0
|
|
#define val x1
|
|
#define valw w1
|
|
#define count x2
|
|
#define dst x3
|
|
#define dstend x4
|
|
#define tmp1 x5
|
|
#define tmp1w w5
|
|
#define tmp2 x6
|
|
#define tmp2w w6
|
|
#define zva_len x7
|
|
#define zva_lenw w7
|
|
|
|
ENTRY_ALIGN (__memset, 6)
|
|
|
|
DELOUSE (0)
|
|
DELOUSE (2)
|
|
|
|
dup v0.16B, valw
|
|
add dstend, dstin, count
|
|
|
|
cmp count, 96
|
|
b.hi L(set_long)
|
|
cmp count, 16
|
|
b.hs L(set_medium)
|
|
mov val, v0.D[0]
|
|
|
|
/* Set 0..15 bytes. */
|
|
tbz count, 3, 1f
|
|
str val, [dstin]
|
|
str val, [dstend, -8]
|
|
ret
|
|
nop
|
|
1: tbz count, 2, 2f
|
|
str valw, [dstin]
|
|
str valw, [dstend, -4]
|
|
ret
|
|
2: cbz count, 3f
|
|
strb valw, [dstin]
|
|
tbz count, 1, 3f
|
|
strh valw, [dstend, -2]
|
|
3: ret
|
|
|
|
/* Set 17..96 bytes. */
|
|
L(set_medium):
|
|
str q0, [dstin]
|
|
tbnz count, 6, L(set96)
|
|
str q0, [dstend, -16]
|
|
tbz count, 5, 1f
|
|
str q0, [dstin, 16]
|
|
str q0, [dstend, -32]
|
|
1: ret
|
|
|
|
.p2align 4
|
|
/* Set 64..96 bytes. Write 64 bytes from the start and
|
|
32 bytes from the end. */
|
|
L(set96):
|
|
str q0, [dstin, 16]
|
|
stp q0, q0, [dstin, 32]
|
|
stp q0, q0, [dstend, -32]
|
|
ret
|
|
|
|
.p2align 3
|
|
nop
|
|
L(set_long):
|
|
and valw, valw, 255
|
|
bic dst, dstin, 15
|
|
str q0, [dstin]
|
|
cmp count, 256
|
|
ccmp valw, 0, 0, cs
|
|
b.eq L(try_zva)
|
|
L(no_zva):
|
|
sub count, dstend, dst /* Count is 16 too large. */
|
|
add dst, dst, 16
|
|
sub count, count, 64 + 16 /* Adjust count and bias for loop. */
|
|
1: stp q0, q0, [dst], 64
|
|
stp q0, q0, [dst, -32]
|
|
L(tail64):
|
|
subs count, count, 64
|
|
b.hi 1b
|
|
2: stp q0, q0, [dstend, -64]
|
|
stp q0, q0, [dstend, -32]
|
|
ret
|
|
|
|
.p2align 3
|
|
L(try_zva):
|
|
mrs tmp1, dczid_el0
|
|
tbnz tmp1w, 4, L(no_zva)
|
|
and tmp1w, tmp1w, 15
|
|
cmp tmp1w, 4 /* ZVA size is 64 bytes. */
|
|
b.ne L(zva_128)
|
|
|
|
/* Write the first and last 64 byte aligned block using stp rather
|
|
than using DC ZVA. This is faster on some cores.
|
|
*/
|
|
L(zva_64):
|
|
str q0, [dst, 16]
|
|
stp q0, q0, [dst, 32]
|
|
bic dst, dst, 63
|
|
stp q0, q0, [dst, 64]
|
|
stp q0, q0, [dst, 96]
|
|
sub count, dstend, dst /* Count is now 128 too large. */
|
|
sub count, count, 128+64+64 /* Adjust count and bias for loop. */
|
|
add dst, dst, 128
|
|
nop
|
|
1: dc zva, dst
|
|
add dst, dst, 64
|
|
subs count, count, 64
|
|
b.hi 1b
|
|
stp q0, q0, [dst, 0]
|
|
stp q0, q0, [dst, 32]
|
|
stp q0, q0, [dstend, -64]
|
|
stp q0, q0, [dstend, -32]
|
|
ret
|
|
|
|
.p2align 3
|
|
L(zva_128):
|
|
cmp tmp1w, 5 /* ZVA size is 128 bytes. */
|
|
b.ne L(zva_other)
|
|
|
|
str q0, [dst, 16]
|
|
stp q0, q0, [dst, 32]
|
|
stp q0, q0, [dst, 64]
|
|
stp q0, q0, [dst, 96]
|
|
bic dst, dst, 127
|
|
sub count, dstend, dst /* Count is now 128 too large. */
|
|
sub count, count, 128+128 /* Adjust count and bias for loop. */
|
|
add dst, dst, 128
|
|
1: dc zva, dst
|
|
add dst, dst, 128
|
|
subs count, count, 128
|
|
b.hi 1b
|
|
stp q0, q0, [dstend, -128]
|
|
stp q0, q0, [dstend, -96]
|
|
stp q0, q0, [dstend, -64]
|
|
stp q0, q0, [dstend, -32]
|
|
ret
|
|
|
|
L(zva_other):
|
|
mov tmp2w, 4
|
|
lsl zva_lenw, tmp2w, tmp1w
|
|
add tmp1, zva_len, 64 /* Max alignment bytes written. */
|
|
cmp count, tmp1
|
|
blo L(no_zva)
|
|
|
|
sub tmp2, zva_len, 1
|
|
add tmp1, dst, zva_len
|
|
add dst, dst, 16
|
|
subs count, tmp1, dst /* Actual alignment bytes to write. */
|
|
bic tmp1, tmp1, tmp2 /* Aligned dc zva start address. */
|
|
beq 2f
|
|
1: stp q0, q0, [dst], 64
|
|
stp q0, q0, [dst, -32]
|
|
subs count, count, 64
|
|
b.hi 1b
|
|
2: mov dst, tmp1
|
|
sub count, dstend, tmp1 /* Remaining bytes to write. */
|
|
subs count, count, zva_len
|
|
b.lo 4f
|
|
3: dc zva, dst
|
|
add dst, dst, zva_len
|
|
subs count, count, zva_len
|
|
b.hs 3b
|
|
4: add count, count, zva_len
|
|
b L(tail64)
|
|
|
|
END (__memset)
|
|
weak_alias (__memset, memset)
|
|
libc_hidden_builtin_def (memset)
|