Home | History | Annotate | Download | only in Ia32 
      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     SECTION .text
     25 
     26 ;------------------------------------------------------------------------------
     27 ;  VOID *
     28 ;  EFIAPI
     29 ;  InternalMemSetMem (
     30 ;    IN VOID   *Buffer,
     31 ;    IN UINTN  Count,
     32 ;    IN UINT8  Value
     33 ;    );
     34 ;------------------------------------------------------------------------------
     35 global ASM_PFX(InternalMemSetMem)
     36 ASM_PFX(InternalMemSetMem):
     37     push    edi
     38     mov     edx, [esp + 12]             ; edx <- Count
     39     mov     edi, [esp + 8]              ; edi <- Buffer
     40     mov     al, [esp + 16]              ; al <- Value
     41     xor     ecx, ecx
     42     sub     ecx, edi
     43     and     ecx, 15                     ; ecx + edi aligns on 16-byte boundary
     44     jz      .0
     45     cmp     ecx, edx
     46     cmova   ecx, edx
     47     sub     edx, ecx
     48     rep     stosb
     49 .0:
     50     mov     ecx, edx
     51     and     edx, 15
     52     shr     ecx, 4                      ; ecx <- # of DQwords to set
     53     jz      @SetBytes
     54     mov     ah, al                      ; ax <- Value | (Value << 8)
     55     add     esp, -16
     56     movdqu  [esp], xmm0                 ; save xmm0
     57     movd    xmm0, eax
     58     pshuflw xmm0, xmm0, 0               ; xmm0[0..63] <- Value repeats 8 times
     59     movlhps xmm0, xmm0                  ; xmm0 <- Value repeats 16 times
     60 .1:
     61     movntdq [edi], xmm0                 ; edi should be 16-byte aligned
     62     add     edi, 16
     63     loop    .1
     64     mfence
     65     movdqu  xmm0, [esp]                 ; restore xmm0
     66     add     esp, 16                     ; stack cleanup
     67 @SetBytes:
     68     mov     ecx, edx
     69     rep     stosb
     70     mov     eax, [esp + 8]              ; eax <- Buffer as return value
     71     pop     edi
     72     ret
     73 
     74