1 files changed, 50 insertions, 0 deletions
diff --git a/roms/edk2/MdePkg/Library/BaseMemoryLibMmx/X64/ZeroMem.nasm b/roms/edk2/MdePkg/Library/BaseMemoryLibMmx/X64/ZeroMem.nasm
new file mode 100644
index 000000000..2a85f15b5
--- /dev/null
+++ b/roms/edk2/MdePkg/Library/BaseMemoryLibMmx/X64/ZeroMem.nasm
@@ -0,0 +1,50 @@
+;------------------------------------------------------------------------------
+;
+; Copyright (c) 2006, Intel Corporation. All rights reserved.<BR>
+; SPDX-License-Identifier: BSD-2-Clause-Patent
+;
+; Module Name:
+;
+;   ZeroMem.nasm
+;
+; Abstract:
+;
+;   ZeroMem function
+;
+; Notes:
+;
+;------------------------------------------------------------------------------
+
+    DEFAULT REL
+    SECTION .text
+
+;------------------------------------------------------------------------------
+;  VOID *
+;  InternalMemZeroMem (
+;    IN VOID   *Buffer,
+;    IN UINTN  Count
+;    );
+;------------------------------------------------------------------------------
+global ASM_PFX(InternalMemZeroMem)
+ASM_PFX(InternalMemZeroMem):
+    push    rdi
+    mov     rdi, rcx
+    mov     rcx, rdx
+    mov     r8, rdi
+    and     edx, 7
+    shr     rcx, 3
+    jz      @ZeroBytes
+    DB      0xf, 0xef, 0xc0             ; pxor mm0, mm0
+.0:
+    DB      0xf, 0xe7, 7                ; movntq [rdi], mm0
+    add     rdi, 8
+    loop    .0
+    DB      0xf, 0xae, 0xf0             ; mfence
+@ZeroBytes:
+    xor     eax, eax
+    mov     ecx, edx
+    rep     stosb
+    mov     rax, r8
+    pop     rdi
+    ret
+