audk/MdePkg/Library/BaseMemoryLibOptDxe/AArch64/SetMem.S

205 lines
5.1 KiB
ArmAsm

//
// Copyright (c) 2012 - 2016, Linaro Limited
// All rights reserved.
// Copyright (c) 2015 ARM Ltd
// All rights reserved.
// SPDX-License-Identifier: BSD-2-Clause-Patent
//
// Assumptions:
//
// ARMv8-a, AArch64, unaligned accesses
//
//
#define dstin x0
#define count x1
#define val x2
#define valw w2
#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
#define L(l) .L ## l
ASM_GLOBAL ASM_PFX(InternalMemSetMem16)
ASM_PFX(InternalMemSetMem16):
AARCH64_BTI(c)
dup v0.8H, valw
lsl count, count, #1
b 0f
ASM_GLOBAL ASM_PFX(InternalMemSetMem32)
ASM_PFX(InternalMemSetMem32):
AARCH64_BTI(c)
dup v0.4S, valw
lsl count, count, #2
b 0f
ASM_GLOBAL ASM_PFX(InternalMemSetMem64)
ASM_PFX(InternalMemSetMem64):
AARCH64_BTI(c)
dup v0.2D, val
lsl count, count, #3
b 0f
ASM_GLOBAL ASM_PFX(InternalMemZeroMem)
ASM_PFX(InternalMemZeroMem):
AARCH64_BTI(c)
movi v0.16B, #0
b 0f
ASM_GLOBAL ASM_PFX(InternalMemSetMem)
ASM_PFX(InternalMemSetMem):
AARCH64_BTI(c)
dup v0.16B, valw
0: add dstend, dstin, count
mov val, v0.D[0]
cmp count, 96
b.hi L(set_long)
cmp count, 16
b.hs L(set_medium)
// 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):
bic dst, dstin, 15
str q0, [dstin]
cmp count, 256
ccmp val, 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)