MdePkg/Library/BaseMemoryLibMmx/X64/SetMem.nasm

   1 ;------------------------------------------------------------------------------
   2 ;
   3 ; Copyright (c) 2006, Intel Corporation. All rights reserved.<BR>
   4 ; This program and the accompanying materials
   5 ; are licensed and made available under the terms and conditions of the BSD License
   6 ; which accompanies this distribution.  The full text of the license may be found at
   7 ; http://opensource.org/licenses/bsd-license.php.
   8 ;
   9 ; THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  10 ; WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  11 ;
  12 ; Module Name:
  13 ;
  14 ;   SetMem.nasm
  15 ;
  16 ; Abstract:
  17 ;
  18 ;   SetMem function
  19 ;
  20 ; Notes:
  21 ;
  22 ;------------------------------------------------------------------------------
  23
  24     DEFAULT REL
  25     SECTION .text
  26
  27 ;------------------------------------------------------------------------------
  28 ; VOID *
  29 ; EFIAPI
  30 ; InternalMemSetMem (
  31 ;   OUT     VOID                      *Buffer,
  32 ;   IN      UINTN                     Length,
  33 ;   IN      UINT8                     Value
  34 ;   );
  35 ;------------------------------------------------------------------------------
  36 global ASM_PFX(InternalMemSetMem)
  37 ASM_PFX(InternalMemSetMem):
  38     push    rdi
  39     mov     rax, r8
  40     mov     ah, al
  41     DB      0x48, 0xf, 0x6e, 0xc0         ; movd mm0, rax
  42     mov     r8, rcx
  43     mov     rdi, r8                     ; rdi <- Buffer
  44     mov     rcx, rdx
  45     and     edx, 7
  46     shr     rcx, 3
  47     jz      @SetBytes
  48     DB      0xf, 0x70, 0xC0, 0x0         ; pshufw mm0, mm0, 0h
  49 .0:
  50     DB      0xf, 0xe7, 0x7              ; movntq [rdi], mm0
  51     add     rdi, 8
  52     loop    .0
  53     mfence
  54 @SetBytes:
  55     mov     ecx, edx
  56     rep     stosb
  57     mov     rax, r8
  58     pop     rdi
  59     ret
  60