1 files changed, 49 insertions, 0 deletions
diff --git a/src/VBox/Devices/EFI/Firmware/MdePkg/Library/BaseMemoryLibMmx/X64/ScanMem8.nasm b/src/VBox/Devices/EFI/Firmware/MdePkg/Library/BaseMemoryLibMmx/X64/ScanMem8.nasm
new file mode 100644
index 00000000..b304315c
--- /dev/null
+++ b/src/VBox/Devices/EFI/Firmware/MdePkg/Library/BaseMemoryLibMmx/X64/ScanMem8.nasm
@@ -0,0 +1,49 @@
+;------------------------------------------------------------------------------
+;
+; Copyright (c) 2006 - 2008, Intel Corporation. All rights reserved.<BR>
+; SPDX-License-Identifier: BSD-2-Clause-Patent
+;
+; Module Name:
+;
+;   ScanMem8.Asm
+;
+; Abstract:
+;
+;   ScanMem8 function
+;
+; Notes:
+;
+;   The following BaseMemoryLib instances contain the same copy of this file:
+;
+;       BaseMemoryLibRepStr
+;       BaseMemoryLibMmx
+;       BaseMemoryLibSse2
+;       BaseMemoryLibOptDxe
+;       BaseMemoryLibOptPei
+;
+;------------------------------------------------------------------------------
+
+    DEFAULT REL
+    SECTION .text
+
+;------------------------------------------------------------------------------
+; CONST VOID *
+; EFIAPI
+; InternalMemScanMem8 (
+;   IN      CONST VOID                *Buffer,
+;   IN      UINTN                     Length,
+;   IN      UINT8                     Value
+;   );
+;------------------------------------------------------------------------------
+global ASM_PFX(InternalMemScanMem8)
+ASM_PFX(InternalMemScanMem8):
+    push    rdi
+    mov     rdi, rcx
+    mov     rcx, rdx
+    mov     rax, r8
+    repne   scasb
+    lea     rax, [rdi - 1]
+    cmovnz  rax, rcx                    ; set rax to 0 if not found
+    pop     rdi
+    ret
+