diff options
Diffstat (limited to 'MdePkg/Library/BaseMemoryLibOptPei/Ia32/CopyMem.asm')
-rw-r--r-- | MdePkg/Library/BaseMemoryLibOptPei/Ia32/CopyMem.asm | 61 |
1 files changed, 61 insertions, 0 deletions
diff --git a/MdePkg/Library/BaseMemoryLibOptPei/Ia32/CopyMem.asm b/MdePkg/Library/BaseMemoryLibOptPei/Ia32/CopyMem.asm new file mode 100644 index 0000000000..d933130ae1 --- /dev/null +++ b/MdePkg/Library/BaseMemoryLibOptPei/Ia32/CopyMem.asm @@ -0,0 +1,61 @@ +;------------------------------------------------------------------------------
+;
+; Copyright (c) 2006, Intel Corporation
+; All rights reserved. This program and the accompanying materials
+; are licensed and made available under the terms and conditions of the BSD License
+; which accompanies this distribution. The full text of the license may be found at
+; http://opensource.org/licenses/bsd-license.php
+;
+; THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+; WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+;
+; Module Name:
+;
+; CopyMem.Asm
+;
+; Abstract:
+;
+; CopyMem function
+;
+; Notes:
+;
+;------------------------------------------------------------------------------
+
+ .386
+ .model flat,C
+ .code
+
+;------------------------------------------------------------------------------
+; VOID *
+; InternalMemCopyMem (
+; IN VOID *Destination,
+; IN VOID *Source,
+; IN UINTN Count
+; )
+;------------------------------------------------------------------------------
+InternalMemCopyMem PROC USES esi edi
+ mov esi, [esp+16] ; esi <- Source
+ mov edi, [esp+12] ; edi <- Destination
+ mov edx, [esp+20] ; edx <- Count
+ cmp esi, edi
+ je @CopyDone
+ cmp edx, 0
+ je @CopyDone
+ lea eax, [esi + edx - 1] ; eax <- End of Source
+ cmp esi, edi
+ jae @CopyBytes
+ cmp eax, edi
+ jb @CopyBytes ; Copy backward if overlapped
+ mov esi, eax ; esi <- End of Source
+ lea edi, [edi + edx - 1] ; edi <- End of Destination
+ std
+@CopyBytes:
+ mov ecx, edx
+ rep movsb ; Copy bytes backward
+ cld
+@CopyDone:
+ mov eax, [esp + 12] ; eax <- Destination as return value
+ ret
+InternalMemCopyMem ENDP
+
+ END
|