From af1a266670d040d2f4083ff309d732d648afba2a Mon Sep 17 00:00:00 2001
From: Angelos Mouzakitis <a.mouzakitis@virtualopensystems.com>
Date: Tue, 10 Oct 2023 14:33:42 +0000
Subject: Add submodule dependency files

Change-Id: Iaf8d18082d3991dec7c0ebbea540f092188eb4ec
---
 .../BaseMemoryLibOptDxe/X64/IsZeroBuffer.nasm      | 49 ++++++++++++++++++++++
 1 file changed, 49 insertions(+)
 create mode 100644 roms/edk2/MdePkg/Library/BaseMemoryLibOptDxe/X64/IsZeroBuffer.nasm

(limited to 'roms/edk2/MdePkg/Library/BaseMemoryLibOptDxe/X64/IsZeroBuffer.nasm')

diff --git a/roms/edk2/MdePkg/Library/BaseMemoryLibOptDxe/X64/IsZeroBuffer.nasm b/roms/edk2/MdePkg/Library/BaseMemoryLibOptDxe/X64/IsZeroBuffer.nasm
new file mode 100644
index 000000000..a6e1d817f
--- /dev/null
+++ b/roms/edk2/MdePkg/Library/BaseMemoryLibOptDxe/X64/IsZeroBuffer.nasm
@@ -0,0 +1,49 @@
+;------------------------------------------------------------------------------
+;
+; Copyright (c) 2016, Intel Corporation. All rights reserved.<BR>
+; SPDX-License-Identifier: BSD-2-Clause-Patent
+;
+; Module Name:
+;
+;   IsZeroBuffer.nasm
+;
+; Abstract:
+;
+;   IsZeroBuffer function
+;
+; Notes:
+;
+;------------------------------------------------------------------------------
+
+    DEFAULT REL
+    SECTION .text
+
+;------------------------------------------------------------------------------
+;  BOOLEAN
+;  EFIAPI
+;  InternalMemIsZeroBuffer (
+;    IN CONST VOID  *Buffer,
+;    IN UINTN       Length
+;    );
+;------------------------------------------------------------------------------
+global ASM_PFX(InternalMemIsZeroBuffer)
+ASM_PFX(InternalMemIsZeroBuffer):
+    push    rdi
+    mov     rdi, rcx                   ; rdi <- Buffer
+    mov     rcx, rdx                   ; rcx <- Length
+    shr     rcx, 3                     ; rcx <- number of qwords
+    and     rdx, 7                     ; rdx <- number of trailing bytes
+    xor     rax, rax                   ; rax <- 0, also set ZF
+    repe    scasq
+    jnz     @ReturnFalse               ; ZF=0 means non-zero element found
+    mov     rcx, rdx
+    repe    scasb
+    jnz     @ReturnFalse
+    pop     rdi
+    mov     rax, 1                     ; return TRUE
+    ret
+@ReturnFalse:
+    pop     rdi
+    xor     rax, rax
+    ret                                ; return FALSE
+
-- 
cgit 1.2.3-korg