diff options
Diffstat (limited to 'EDK/Foundation/Library/EdkIIGlueLib/Library/BaseMemoryLib/X64/CopyMem.asm')
-rw-r--r-- | EDK/Foundation/Library/EdkIIGlueLib/Library/BaseMemoryLib/X64/CopyMem.asm | 61 |
1 files changed, 61 insertions, 0 deletions
diff --git a/EDK/Foundation/Library/EdkIIGlueLib/Library/BaseMemoryLib/X64/CopyMem.asm b/EDK/Foundation/Library/EdkIIGlueLib/Library/BaseMemoryLib/X64/CopyMem.asm new file mode 100644 index 0000000..0297975 --- /dev/null +++ b/EDK/Foundation/Library/EdkIIGlueLib/Library/BaseMemoryLib/X64/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: +; +;------------------------------------------------------------------------------ + + .code + +;------------------------------------------------------------------------------ +; VOID * +; EFIAPI +; InternalMemCopyMem ( +; IN VOID *Destination, +; IN VOID *Source, +; IN UINTN Count +; ) +;------------------------------------------------------------------------------ +InternalMemCopyMem PROC USES rsi rdi + mov rsi, rdx ; rsi <- Source + mov rdi, rcx ; rdi <- Destination + lea r9, [rsi + r8 - 1] ; r9 <- End of Source + cmp rsi, rdi + mov rax, rdi ; rax <- Destination as return value + jae @F + cmp r9, rdi + jae @CopyBackward ; Copy backward if overlapped +@@: + mov rcx, r8 + and r8, 7 + shr rcx, 3 + rep movsq ; Copy as many Qwords as possible + jmp @CopyBytes +@CopyBackward: + mov rsi, r9 ; rsi <- End of Source + lea rdi, [rdi + r8 - 1] ; esi <- End of Destination + std ; set direction flag +@CopyBytes: + mov rcx, r8 + rep movsb ; Copy bytes backward + cld + ret +InternalMemCopyMem ENDP + + END |