1 files changed, 71 insertions, 0 deletions
diff --git a/src/VBox/Runtime/common/asm/ASMSerializeInstruction-iret.asm b/src/VBox/Runtime/common/asm/ASMSerializeInstruction-iret.asm
new file mode 100644
index 00000000..2c0e14a2
--- /dev/null
+++ b/src/VBox/Runtime/common/asm/ASMSerializeInstruction-iret.asm
@@ -0,0 +1,71 @@
+; $Id: ASMSerializeInstruction-iret.asm $
+;; @file
+; IPRT - ASMSerializeInstruction() using iret.
+;
+
+;
+; Copyright (C) 2006-2022 Oracle and/or its affiliates.
+;
+; This file is part of VirtualBox base platform packages, as
+; available from https://www.virtualbox.org.
+;
+; This program is free software; you can redistribute it and/or
+; modify it under the terms of the GNU General Public License
+; as published by the Free Software Foundation, in version 3 of the
+; License.
+;
+; This program is distributed in the hope that it will be useful, but
+; WITHOUT ANY WARRANTY; without even the implied warranty of
+; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+; General Public License for more details.
+;
+; You should have received a copy of the GNU General Public License
+; along with this program; if not, see <https://www.gnu.org/licenses>.
+;
+; The contents of this file may alternatively be used under the terms
+; of the Common Development and Distribution License Version 1.0
+; (CDDL), a copy of it is provided in the "COPYING.CDDL" file included
+; in the VirtualBox 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.
+;
+; SPDX-License-Identifier: GPL-3.0-only OR CDDL-1.0
+;
+
+
+;*******************************************************************************
+;* Header Files                                                                *
+;*******************************************************************************
+%include "iprt/asmdefs.mac"
+
+BEGINCODE
+
+
+;;
+; Executes a serializing instruction.
+;
+; The IRET instruction is rather expensive, but unlike the CPUID instruction it
+; will not result in a VM EXIT when running in a virtual machine.
+;
+RT_BEGINPROC ASMSerializeInstructionIRet
+        pop     xAX
+%ifdef RT_ARCH_AMD64
+        mov     rdx, xSP
+        mov     ecx, ss
+        push    rcx
+        push    rdx
+        pushfq
+        mov     ecx, cs
+        push    rcx
+        push    rax
+        iretq
+%elifdef RT_ARCH_X86
+        pushf
+        push    cs
+        push    xAX
+        iret
+%endif
+ENDPROC            ASMSerializeInstructionIRet
+