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| ;------------------------------------------------------------------------------
| ;
| ; Copyright (c) 2006, Intel Corporation. All rights reserved.<BR>
| ; SPDX-License-Identifier: BSD-2-Clause-Patent
| ;
| ; Module Name:
| ;
| ; SetMem.nasm
| ;
| ; Abstract:
| ;
| ; SetMem function
| ;
| ; Notes:
| ;
| ;------------------------------------------------------------------------------
|
| DEFAULT REL
| SECTION .text
|
| ;------------------------------------------------------------------------------
| ; VOID *
| ; InternalMemSetMem (
| ; IN VOID *Buffer,
| ; IN UINTN Count,
| ; IN UINT8 Value
| ; )
| ;------------------------------------------------------------------------------
| global ASM_PFX(InternalMemSetMem)
| ASM_PFX(InternalMemSetMem):
| push rdi
| mov rdi, rcx ; rdi <- Buffer
| mov al, r8b ; al <- Value
| mov r9, rdi ; r9 <- Buffer as return value
| xor rcx, rcx
| sub rcx, rdi
| and rcx, 15 ; rcx + rdi aligns on 16-byte boundary
| jz .0
| cmp rcx, rdx
| cmova rcx, rdx
| sub rdx, rcx
| rep stosb
| .0:
| mov rcx, rdx
| and rdx, 63
| shr rcx, 6
| jz @SetBytes
| mov ah, al ; ax <- Value repeats twice
| movdqa [rsp + 0x10], xmm0 ; save xmm0
| movd xmm0, eax ; xmm0[0..16] <- Value repeats twice
| pshuflw xmm0, xmm0, 0 ; xmm0[0..63] <- Value repeats 8 times
| movlhps xmm0, xmm0 ; xmm0 <- Value repeats 16 times
| .1:
| movntdq [rdi], xmm0 ; rdi should be 16-byte aligned
| movntdq [rdi + 16], xmm0
| movntdq [rdi + 32], xmm0
| movntdq [rdi + 48], xmm0
| add rdi, 64
| loop .1
| mfence
| movdqa xmm0, [rsp + 0x10] ; restore xmm0
| @SetBytes:
| mov ecx, edx ; high 32 bits of rcx are always zero
| rep stosb
| mov rax, r9 ; rax <- Return value
| pop rdi
| ret
|
|
|
