MdePkg/Library/BaseMemoryLibMmx/X64/SetMem32.nasm

   1 ;------------------------------------------------------------------------------
   2 ;
   3 ; Copyright (c) 2006, Intel Corporation. All rights reserved.<BR>
   4 ; SPDX-License-Identifier: BSD-2-Clause-Patent
   5 ;
   6 ; Module Name:
   7 ;
   8 ;   SetMem32.nasm
   9 ;
  10 ; Abstract:
  11 ;
  12 ;   SetMem32 function
  13 ;
  14 ; Notes:
  15 ;
  16 ;------------------------------------------------------------------------------
  17
  18     DEFAULT REL
  19     SECTION .text
  20
  21 ;------------------------------------------------------------------------------
  22 ;  VOID *
  23 ;  InternalMemSetMem32 (
  24 ;    IN VOID   *Buffer,
  25 ;    IN UINTN  Count,
  26 ;    IN UINT32 Value
  27 ;    )
  28 ;------------------------------------------------------------------------------
  29 global ASM_PFX(InternalMemSetMem32)
  30 ASM_PFX(InternalMemSetMem32):
  31     DB      0x49, 0xf, 0x6e, 0xc0         ; movd mm0, r8 (Value)
  32     mov     rax, rcx                    ; rax <- Buffer
  33     xchg    rcx, rdx                    ; rcx <- Count  rdx <- Buffer
  34     shr     rcx, 1                      ; rcx <- # of qwords to set
  35     jz      @SetDwords
  36     DB      0xf, 0x70, 0xC0, 0x44         ; pshufw mm0, mm0, 44h
  37 .0:
  38     DB      0xf, 0xe7, 0x2              ; movntq [rdx], mm0
  39     lea     rdx, [rdx + 8]              ; use "lea" to avoid flag changes
  40     loop    .0
  41     mfence
  42 @SetDwords:
  43     jnc     .1
  44     DB      0xf, 0x7e, 0x2               ; movd [rdx], mm0
  45 .1:
  46     ret
  47