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-rw-r--r--src/VBox/Runtime/common/math/frexpl.cpp167
1 files changed, 167 insertions, 0 deletions
diff --git a/src/VBox/Runtime/common/math/frexpl.cpp b/src/VBox/Runtime/common/math/frexpl.cpp
new file mode 100644
index 00000000..161d9b35
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+++ b/src/VBox/Runtime/common/math/frexpl.cpp
@@ -0,0 +1,167 @@
+/* $Id: frexpl.cpp $ */
+/** @file
+ * IPRT - No-CRT - frexpl().
+ */
+
+/*
+ * Copyright (C) 2022-2023 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 *
+*********************************************************************************************************************************/
+#define IPRT_NO_CRT_FOR_3RD_PARTY
+#include "internal/nocrt.h"
+#include <iprt/nocrt/math.h>
+#include <iprt/assertcompile.h>
+#include <iprt/nocrt/limits.h>
+#ifdef RT_COMPILER_WITH_128BIT_LONG_DOUBLE
+# include <iprt/uint128.h>
+#endif
+
+
+/* Similar to the fxtract instruction. */
+#undef frexpl
+long double RT_NOCRT(frexpl)(long double lrdValue, int *piExp)
+{
+#ifdef RT_COMPILER_WITH_64BIT_LONG_DOUBLE
+ RTFLOAT64U Value;
+ AssertCompile(sizeof(Value) == sizeof(lrdValue));
+ Value.lrd = lrdValue;
+
+ if (RTFLOAT64U_IS_NORMAL(&Value))
+ {
+ *piExp = (int)Value.s.uExponent - RTFLOAT64U_EXP_BIAS + 1;
+ Value.s.uExponent = RTFLOAT64U_EXP_BIAS - 1;
+ }
+ else if (RTFLOAT64U_IS_ZERO(&Value))
+ {
+ *piExp = 0;
+ return lrdValue;
+ }
+ else if (RTFLOAT64U_IS_SUBNORMAL(&Value))
+ {
+ int iExp = -RTFLOAT64U_EXP_BIAS + 1;
+ uint64_t uFraction = Value.s64.uFraction;
+ while (!(uFraction & RT_BIT_64(RTFLOAT64U_FRACTION_BITS)))
+ {
+ iExp--;
+ uFraction <<= 1;
+ }
+ Value.s64.uFraction = uFraction;
+ Value.s64.uExponent = RTFLOAT64U_EXP_BIAS - 1;
+ *piExp = iExp + 1;
+ }
+ else
+ {
+ /* NaN, Inf */
+ *piExp = Value.s.fSign ? INT_MIN : INT_MAX;
+ return lrdValue;
+ }
+ return Value.lrd;
+
+#elif defined(RT_COMPILER_WITH_80BIT_LONG_DOUBLE)
+ RTFLOAT80U2 Value;
+ Value.r = lrdValue;
+
+ if (RTFLOAT80U_IS_NORMAL(&Value))
+ {
+ *piExp = (int)Value.s.uExponent - RTFLOAT80U_EXP_BIAS + 1;
+ Value.s.uExponent = RTFLOAT80U_EXP_BIAS - 1;
+ }
+ else if (RTFLOAT80U_IS_ZERO(&Value))
+ {
+ *piExp = 0;
+ return lrdValue;
+ }
+ else if (RTFLOAT80U_IS_DENORMAL_OR_PSEUDO_DENORMAL(&Value))
+ {
+ int iExp = -RTFLOAT80U_EXP_BIAS + 1;
+ while (!(Value.s.uMantissa & RT_BIT_64(RTFLOAT80U_FRACTION_BITS)))
+ {
+ iExp--;
+ Value.s.uMantissa <<= 1;
+ }
+ Value.s.uExponent = RTFLOAT80U_EXP_BIAS - 1;
+ *piExp = iExp + 1;
+ }
+ else /* NaN, Inf */
+ {
+ *piExp = Value.s.fSign ? INT_MIN : INT_MAX;
+ return lrdValue;
+ }
+ return Value.r;
+
+
+#elif defined(RT_COMPILER_WITH_128BIT_LONG_DOUBLE)
+ RTFLOAT128U Value;
+ AssertCompile(sizeof(Value) == sizeof(lrdValue));
+ Value.r = lrdValue;
+
+ if (RTFLOAT128U_IS_NORMAL(&Value))
+ {
+ *piExp = (int)Value.s.uExponent - RTFLOAT128U_EXP_BIAS + 1;
+ Value.s.uExponent = RTFLOAT128U_EXP_BIAS - 1;
+ }
+ else if (RTFLOAT128U_IS_ZERO(&Value))
+ {
+ *piExp = 0;
+ return lrdValue;
+ }
+ else if (RTFLOAT128U_IS_SUBNORMAL(&Value))
+ {
+ int iExp = -RTFLOAT128U_EXP_BIAS + 1;
+ RTUINT128U uFraction;
+ uFraction.s.Hi = Value.s64.uFractionHi;
+ uFraction.s.Lo = Value.s64.uFractionLo;
+ while (!(uFraction.s.Hi & RT_BIT_64(RTFLOAT128U_FRACTION_BITS - 64)))
+ {
+ iExp--;
+ RTUInt128AssignShiftLeft(&uFraction, 1);
+ }
+ Value.s64.uFractionHi = uFraction.s.Hi;
+ Value.s64.uFractionLo = uFraction.s.Lo;
+ Value.s64.uExponent = RTFLOAT64U_EXP_BIAS - 1;
+ *piExp = iExp + 1;
+ }
+ else
+ {
+ /* NaN, Inf */
+ *piExp = Value.s.fSign ? INT_MIN : INT_MAX;
+ return lrdValue;
+ }
+ return Value.r;
+#else
+# error "Port ME!"
+#endif
+}
+RT_ALIAS_AND_EXPORT_NOCRT_SYMBOL(frexpl);
+