summaryrefslogtreecommitdiffstats
path: root/MdePkg/Library/BaseMemoryLibSse2/x64/CopyMem.asm
diff options
context:
space:
mode:
Diffstat (limited to 'MdePkg/Library/BaseMemoryLibSse2/x64/CopyMem.asm')
-rw-r--r--MdePkg/Library/BaseMemoryLibSse2/x64/CopyMem.asm78
1 files changed, 78 insertions, 0 deletions
diff --git a/MdePkg/Library/BaseMemoryLibSse2/x64/CopyMem.asm b/MdePkg/Library/BaseMemoryLibSse2/x64/CopyMem.asm
new file mode 100644
index 0000000000..955cd25f36
--- /dev/null
+++ b/MdePkg/Library/BaseMemoryLibSse2/x64/CopyMem.asm
@@ -0,0 +1,78 @@
+;------------------------------------------------------------------------------
+;
+; 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 *
+; _mem_CopyMem (
+; 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, [rdi + r8 - 1] ; r9 <- Last byte of Destination
+ cmp rsi, rdi
+ mov rax, rdi ; rax <- Destination as return value
+ jae @F ; Copy forward if Source > Destination
+ cmp r9, rsi ; Overlapped?
+ jae @CopyBackward ; Copy backward if overlapped
+@@:
+ xor rcx, rcx
+ sub rcx, rdi ; rcx <- -rdi
+ and rcx, 15 ; rcx + rsi should be 16 bytes aligned
+ jz @F ; skip if rcx == 0
+ cmp rcx, r8
+ cmova rcx, r8
+ sub r8, rcx
+ rep movsb
+@@:
+ mov rcx, r8
+ and r8, 15
+ shr rcx, 4 ; rcx <- # of DQwords to copy
+ jz @CopyBytes
+ movdqa [rsp + 18h], xmm0 ; save xmm0 on stack
+@@:
+ 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 @B
+ mfence
+ movdqa xmm0, [rsp + 18h] ; restore xmm0
+ jmp @CopyBytes ; copy remaining bytes
+@CopyBackward:
+ mov rdi, r9 ; rdi <- Last byte of Destination
+ lea rsi, [rsi + r8 - 1] ; rsi <- Last byte of Source
+ std
+@CopyBytes:
+ mov rcx, r8
+ rep movsb
+ cld
+ ret
+InternalMemCopyMem ENDP
+
+ END