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-rw-r--r--MdePkg/Library/BaseMemoryLibOptDxe/X64/SetMem.S65
1 files changed, 65 insertions, 0 deletions
diff --git a/MdePkg/Library/BaseMemoryLibOptDxe/X64/SetMem.S b/MdePkg/Library/BaseMemoryLibOptDxe/X64/SetMem.S
new file mode 100644
index 0000000000..3453431926
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+++ b/MdePkg/Library/BaseMemoryLibOptDxe/X64/SetMem.S
@@ -0,0 +1,65 @@
+;------------------------------------------------------------------------------
+;
+; 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:
+;
+; SetMem.Asm
+;
+; Abstract:
+;
+; SetMem function
+;
+; Notes:
+;
+;------------------------------------------------------------------------------
+
+ .code
+
+;------------------------------------------------------------------------------
+; VOID *
+; EFIAPI
+; InternalMemSetMem (
+; IN VOID *Buffer,
+; IN UINTN Count,
+; IN UINT8 Value
+; )
+;------------------------------------------------------------------------------
+.intel_syntax noprefix
+.globl ASM_PFX(InternalMemSetMem)
+ASM_PFX(InternalMemZeroMem):
+InternalMemSetMem PROC USES rdi rbx
+ push rdi
+ push rbx
+ push rcx ; push Buffer
+ mov rax, r8 ; rax = Value
+ and rax, 0ffh ; rax = lower 8 bits of r8, upper 56 bits are 0
+ mov ah, al ; ah = al
+ mov bx, ax ; bx = ax
+ shl rax, 10h ; rax = ax << 16
+ mov ax, bx ; ax = bx
+ mov rbx, rax ; ebx = eax
+ shl rax, 20h ; rax = rax << 32
+ or rax, rbx ; eax = ebx
+ mov rdi, rcx ; rdi = Buffer
+ mov rcx, rdx ; rcx = Count
+ shr rcx, 3 ; rcx = rcx / 8
+ cld
+ rep stosq
+ mov rcx, rdx ; rcx = rdx
+ and rcx, 7 ; rcx = rcx & 7
+ rep stosb
+ pop rax ; rax = Buffer
+ pop rbx
+ pop rdi
+ ret
+InternalMemSetMem ENDP
+
+ END