1 files changed, 82 insertions, 0 deletions
diff --git a/src/VBox/Runtime/common/math/fegetexcept.asm b/src/VBox/Runtime/common/math/fegetexcept.asm
new file mode 100644
index 00000000..cdfdbfb7
--- /dev/null
+++ b/src/VBox/Runtime/common/math/fegetexcept.asm
@@ -0,0 +1,82 @@
+; $Id: fegetexcept.asm $
+;; @file
+; IPRT - No-CRT fegetexcept - AMD64 & X86.
+;
+
+;
+; Copyright (C) 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
+;
+
+
+%define RT_ASM_WITH_SEH64
+%include "iprt/asmdefs.mac"
+%include "iprt/x86.mac"
+
+
+BEGINCODE
+
+;;
+; Gets the mask of enabled exceptions, e.g. unmasked (BSD/GNU extension).
+;
+; @returns  eax = inverted x87/sse exception mask (X86_MXCSR_XCPT_FLAGS).
+;           Will not return X86_FSW_SF.
+;
+RT_NOCRT_BEGINPROC fegetexcept
+        push    xBP
+        SEH64_PUSH_xBP
+        mov     xBP, xSP
+        SEH64_SET_FRAME_xBP 0
+        sub     xSP, 10h
+        SEH64_ALLOCATE_STACK 10h
+        SEH64_END_PROLOGUE
+
+        ;
+        ; Save control word and isolate the exception mask.
+        ;
+        ; On 64-bit we'll use the MXCSR since the windows compiler/CRT doesn't
+        ; necessarily keep them in sync.  We'll still return the x87-style flags.
+        ;
+%ifdef RT_ARCH_AMD64
+        stmxcsr [xBP - 10h]
+        mov     eax, [xBP - 10h]
+        shr     eax, X86_MXCSR_XCPT_MASK_SHIFT
+%else
+        fstcw   [xBP - 10h]
+        movzx   eax, word [xBP - 10h]
+%endif
+
+        not     eax                         ; Invert it as we return the enabled rather than masked exceptions.
+        and     eax, X86_MXCSR_XCPT_FLAGS   ; Use the SSE mask so we don't return X86_FSW_SF here.
+
+.return_val:
+        leave
+        ret
+ENDPROC   RT_NOCRT(fegetexcept)
+