diff options
Diffstat (limited to 'MdePkg/Library/BaseMemoryLibRepStr/X64/CopyMem.S')
| -rw-r--r-- | MdePkg/Library/BaseMemoryLibRepStr/X64/CopyMem.S | 35 |
1 files changed, 17 insertions, 18 deletions
diff --git a/MdePkg/Library/BaseMemoryLibRepStr/X64/CopyMem.S b/MdePkg/Library/BaseMemoryLibRepStr/X64/CopyMem.S index 4477006e41..5eb1d46547 100644 --- a/MdePkg/Library/BaseMemoryLibRepStr/X64/CopyMem.S +++ b/MdePkg/Library/BaseMemoryLibRepStr/X64/CopyMem.S @@ -3,7 +3,7 @@ #
#------------------------------------------------------------------------------
#
-# Copyright (c) 2006 - 2008, Intel Corporation
+# Copyright (c) 2006 - 2009, 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
@@ -34,34 +34,33 @@ # IN UINTN Count
# )
#------------------------------------------------------------------------------
-.intel_syntax noprefix
ASM_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 <- End of Source
- cmp rsi, rdi
- mov rax, rdi # rax <- Destination as return value
+ pushq %rsi
+ pushq %rdi
+ movq %rdx, %rsi # rsi <- Source
+ movq %rcx, %rdi # rdi <- Destination
+ leaq -1(%rsi, %r8,), %r9 # r9 <- End of Source
+ cmpq %rdi, %rsi
+ movq %rdi, %rax # rax <- Destination as return value
jae L0
- cmp r9, rdi
+ cmpq %rdi, %r9
jae L_CopyBackward # Copy backward if overlapped
L0:
- mov rcx, r8
- and r8, 7
- shr rcx, 3
+ movq %r8, %rcx
+ andq $7, %r8
+ shrq $3, %rcx
rep movsq # Copy as many Qwords as possible
jmp L_CopyBytes
L_CopyBackward:
- mov rsi, r9 # rsi <- End of Source
- lea rdi, [rdi + r8 - 1] # esi <- End of Destination
+ movq %r9, %rsi # rsi <- End of Source
+ leaq -1(%rdi, %r8), %rdi # esi <- End of Destination
std # set direction flag
L_CopyBytes:
- mov rcx, r8
+ movq %r8, %rcx
rep movsb # Copy bytes backward
cld
- pop rdi
- pop rsi
+ popq %rdi
+ popq %rsi
ret
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