1 files changed, 84 insertions, 0 deletions
diff --git a/src/VBox/ValidationKit/bootsectors/bs3kit/bs3-cmn-ExtCtxInit.c b/src/VBox/ValidationKit/bootsectors/bs3kit/bs3-cmn-ExtCtxInit.c
new file mode 100644
index 00000000..944f6d45
--- /dev/null
+++ b/src/VBox/ValidationKit/bootsectors/bs3kit/bs3-cmn-ExtCtxInit.c
@@ -0,0 +1,84 @@
+/* $Id: bs3-cmn-ExtCtxInit.c $ */
+/** @file
+ * BS3Kit - Bs3ExtCtxInit
+ */
+
+/*
+ * Copyright (C) 2007-2023 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 "bs3kit-template-header.h"
+#include <iprt/asm-amd64-x86.h>
+
+
+#undef Bs3ExtCtxInit
+BS3_CMN_DEF(PBS3EXTCTX, Bs3ExtCtxInit,(PBS3EXTCTX pExtCtx, uint16_t cbExtCtx, uint64_t fFlags))
+{
+    Bs3MemSet(pExtCtx, 0, cbExtCtx);
+
+    if (cbExtCtx >= RT_UOFFSETOF(BS3EXTCTX, Ctx) + sizeof(X86FXSTATE) + sizeof(X86XSAVEHDR))
+    {
+        BS3_ASSERT(fFlags & XSAVE_C_X87);
+        pExtCtx->enmMethod = BS3EXTCTXMETHOD_XSAVE;
+        pExtCtx->Ctx.x.Hdr.bmXState = fFlags;
+
+        /* Setting bit 6 (0x40) here as it kept sneaking in when loading/saving state in 16-bit and v8086 mode. */
+        pExtCtx->Ctx.x.x87.FCW        = X86_FCW_RC_NEAREST | X86_FCW_PC_64 /* go figure:*/ | RT_BIT(6);
+        pExtCtx->Ctx.x.x87.MXCSR      = X86_MXCSR_RC_NEAREST;
+        pExtCtx->Ctx.x.x87.MXCSR_MASK = 0xffff;
+    }
+    else if (cbExtCtx >= RT_UOFFSETOF(BS3EXTCTX, Ctx) + sizeof(X86FXSTATE))
+    {
+        BS3_ASSERT(fFlags == 0);
+        pExtCtx->enmMethod = BS3EXTCTXMETHOD_FXSAVE;
+        pExtCtx->Ctx.x87.FCW          = X86_FCW_RC_NEAREST | X86_FCW_PC_64 /* go figure:*/ | RT_BIT(6);
+        pExtCtx->Ctx.x87.MXCSR        = X86_MXCSR_RC_NEAREST;
+        pExtCtx->Ctx.x87.MXCSR_MASK   = 0xffff;
+    }
+    else
+    {
+        BS3_ASSERT(fFlags == 0);
+        BS3_ASSERT(cbExtCtx >= RT_UOFFSETOF(BS3EXTCTX, Ctx) + sizeof(X86FPUSTATE));
+        pExtCtx->enmMethod = BS3EXTCTXMETHOD_ANCIENT;
+        pExtCtx->Ctx.Ancient.FCW      = X86_FCW_RC_NEAREST | X86_FCW_PC_64 /* go figure:*/ | RT_BIT(6);
+        pExtCtx->Ctx.Ancient.FTW      = UINT16_MAX;  /* all registers empty */
+    }
+
+    pExtCtx->cb             = cbExtCtx;
+    pExtCtx->u16Magic       = BS3EXTCTX_MAGIC;
+    pExtCtx->fXcr0Nominal   = fFlags;
+    pExtCtx->fXcr0Saved     = fFlags;
+    return pExtCtx;
+}
+