mirror of
https://github.com/reactos/reactos.git
synced 2024-11-01 12:26:32 +00:00
46 lines
896 B
ArmAsm
46 lines
896 B
ArmAsm
/*
|
|
* PROJECT: ReactOS Kernel
|
|
* LICENSE: GPL-2.0-or-later (https://spdx.org/licenses/GPL-2.0-or-later)
|
|
* PURPOSE: Fast zeroing of pages
|
|
* COPYRIGHT: Copyright 2021 Jérôme Gardou <jerome.gardou@reactos.org>
|
|
*/
|
|
|
|
#include <asm.inc>
|
|
|
|
/* FUNCTIONS ****************************************************************/
|
|
.code
|
|
|
|
/* Benchmarking from Timo on some AMD machine:
|
|
rep movsq : 128
|
|
movaps 175
|
|
movnti 620
|
|
movntdq: 620
|
|
movntps: 620
|
|
MS KeZeroPages (movnti unrolled): 883
|
|
MS KeZeroSinglePage (mov): 346
|
|
|
|
whole discussion in https://github.com/reactos/reactos/pull/3765
|
|
We stick with rep stosq.
|
|
*/
|
|
|
|
/*
|
|
* VOID
|
|
* KeZeroPages(PVOID Ptr, ULONG Size);
|
|
*/
|
|
PUBLIC KeZeroPages
|
|
FUNC KeZeroPages
|
|
push rdi
|
|
.PUSHREG rdi
|
|
.ENDPROLOG
|
|
|
|
mov rdi, rcx
|
|
mov ecx, edx
|
|
shr ecx, 3
|
|
xor rax, rax
|
|
rep stosq
|
|
pop rdi
|
|
ret
|
|
ENDFUNC
|
|
|
|
END
|