1 files changed, 40 insertions, 0 deletions
diff --git a/roms/edk2/MdePkg/Library/BaseMemoryLibMmx/X64/SetMem64.nasm b/roms/edk2/MdePkg/Library/BaseMemoryLibMmx/X64/SetMem64.nasm
new file mode 100644
index 000000000..f517e1d23
--- /dev/null
+++ b/roms/edk2/MdePkg/Library/BaseMemoryLibMmx/X64/SetMem64.nasm
@@ -0,0 +1,40 @@
+;------------------------------------------------------------------------------
+;
+; Copyright (c) 2006, Intel Corporation. All rights reserved.<BR>
+; SPDX-License-Identifier: BSD-2-Clause-Patent
+;
+; Module Name:
+;
+;   SetMem64.nasm
+;
+; Abstract:
+;
+;   SetMem64 function
+;
+; Notes:
+;
+;------------------------------------------------------------------------------
+
+    DEFAULT REL
+    SECTION .text
+
+;------------------------------------------------------------------------------
+;  VOID *
+;  InternalMemSetMem64 (
+;    IN VOID   *Buffer,
+;    IN UINTN  Count,
+;    IN UINT64 Value
+;    )
+;------------------------------------------------------------------------------
+global ASM_PFX(InternalMemSetMem64)
+ASM_PFX(InternalMemSetMem64):
+    DB      0x49, 0xf, 0x6e, 0xc0         ; movd mm0, r8 (Value)
+    mov     rax, rcx                    ; rax <- Buffer
+    xchg    rcx, rdx                    ; rcx <- Count
+.0:
+    DB      0xf, 0xe7, 0x2              ; movntq  [rdx], mm0
+    add     rdx, 8
+    loop    .0
+    mfence
+    ret
+