1 files changed, 49 insertions, 0 deletions
diff --git a/src/VBox/Runtime/common/asm/ASMSerializeInstruction-cpuid.asm b/src/VBox/Runtime/common/asm/ASMSerializeInstruction-cpuid.asm
new file mode 100644
index 00000000..b5294967
--- /dev/null
+++ b/src/VBox/Runtime/common/asm/ASMSerializeInstruction-cpuid.asm
@@ -0,0 +1,49 @@
+; $Id: ASMSerializeInstruction-cpuid.asm $
+;; @file
+; IPRT - ASMSerializeInstruction() using cpuid.
+;
+
+;
+; Copyright (C) 2006-2019 Oracle Corporation
+;
+; This file is part of VirtualBox Open Source Edition (OSE), as
+; available from http://www.virtualbox.org. This file is free software;
+; you can redistribute it and/or modify it under the terms of the GNU
+; General Public License (GPL) as published by the Free Software
+; Foundation, in version 2 as it comes in the "COPYING" file of the
+; VirtualBox OSE distribution. VirtualBox OSE is distributed in the
+; hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
+;
+; The contents of this file may alternatively be used under the terms
+; of the Common Development and Distribution License Version 1.0
+; (CDDL) only, as it comes in the "COPYING.CDDL" file of the
+; VirtualBox OSE distribution, in which case the provisions of the
+; CDDL are applicable instead of those of the GPL.
+;
+; You may elect to license modified versions of this file under the
+; terms and conditions of either the GPL or the CDDL or both.
+;
+
+
+;*******************************************************************************
+;* Header Files                                                                *
+;*******************************************************************************
+%include "iprt/asmdefs.mac"
+
+BEGINCODE
+
+
+;;
+; Executes a seralizing instruction.
+;
+; The CPUID instruction isn't fast or slow, but it always triggers a VM EXIT in
+; a virtualized environment, which is prohibitively expensive.
+;
+BEGINPROC_EXPORTED ASMSerializeInstructionCpuId
+        push    xBX
+        xor     eax, eax
+        cpuid
+        pop     xBX
+        ret
+ENDPROC            ASMSerializeInstructionCpuId
+