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