diff options
Diffstat (limited to 'Core/MdePkg/Library/BaseMemoryLibSse2/X64/CopyMem.nasm')
| -rw-r--r-- | Core/MdePkg/Library/BaseMemoryLibSse2/X64/CopyMem.nasm | 83 |
1 files changed, 83 insertions, 0 deletions
diff --git a/Core/MdePkg/Library/BaseMemoryLibSse2/X64/CopyMem.nasm b/Core/MdePkg/Library/BaseMemoryLibSse2/X64/CopyMem.nasm new file mode 100644 index 0000000000..d312c2dfe4 --- /dev/null +++ b/Core/MdePkg/Library/BaseMemoryLibSse2/X64/CopyMem.nasm @@ -0,0 +1,83 @@ +;------------------------------------------------------------------------------
+;
+; Copyright (c) 2006, Intel Corporation. All rights reserved.<BR>
+; 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.nasm
+;
+; Abstract:
+;
+; CopyMem function
+;
+; Notes:
+;
+;------------------------------------------------------------------------------
+
+ DEFAULT REL
+ SECTION .text
+
+;------------------------------------------------------------------------------
+; VOID *
+; EFIAPI
+; InternalMemCopyMem (
+; IN VOID *Destination,
+; IN VOID *Source,
+; IN UINTN Count
+; );
+;------------------------------------------------------------------------------
+global ASM_PFX(InternalMemCopyMem)
+ASM_PFX(InternalMemCopyMem):
+ push rsi
+ push rdi
+ mov rsi, rdx ; rsi <- Source
+ mov rdi, rcx ; rdi <- Destination
+ lea r9, [rsi + r8 - 1] ; r9 <- Last byte of Source
+ cmp rsi, rdi
+ mov rax, rdi ; rax <- Destination as return value
+ jae .0 ; Copy forward if Source > Destination
+ cmp r9, rdi ; Overlapped?
+ jae @CopyBackward ; Copy backward if overlapped
+.0:
+ xor rcx, rcx
+ sub rcx, rdi ; rcx <- -rdi
+ and rcx, 15 ; rcx + rsi should be 16 bytes aligned
+ jz .1 ; skip if rcx == 0
+ cmp rcx, r8
+ cmova rcx, r8
+ sub r8, rcx
+ rep movsb
+.1:
+ mov rcx, r8
+ and r8, 15
+ shr rcx, 4 ; rcx <- # of DQwords to copy
+ jz @CopyBytes
+ movdqa [rsp + 0x18], xmm0 ; save xmm0 on stack
+.2:
+ movdqu xmm0, [rsi] ; rsi may not be 16-byte aligned
+ movntdq [rdi], xmm0 ; rdi should be 16-byte aligned
+ add rsi, 16
+ add rdi, 16
+ loop .2
+ mfence
+ movdqa xmm0, [rsp + 0x18] ; restore xmm0
+ jmp @CopyBytes ; copy remaining bytes
+@CopyBackward:
+ mov rsi, r9 ; rsi <- Last byte of Source
+ lea rdi, [rdi + r8 - 1] ; rdi <- Last byte of Destination
+ std
+@CopyBytes:
+ mov rcx, r8
+ rep movsb
+ cld
+ pop rdi
+ pop rsi
+ ret
+
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