1 files changed, 76 insertions, 0 deletions
diff --git a/src/libs/softfloat-3e/source/extF80_tan.c b/src/libs/softfloat-3e/source/extF80_tan.c
new file mode 100644
index 00000000..24c0430f
--- /dev/null
+++ b/src/libs/softfloat-3e/source/extF80_tan.c
@@ -0,0 +1,76 @@
+/** @file
+ * SoftFloat - VBox Extension - extF80_tan.
+ */
+
+/*
+ * 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>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-only
+ */
+
+
+/*********************************************************************************************************************************
+*   Header Files                                                                                                                 *
+*********************************************************************************************************************************/
+#include <stdbool.h>
+#include <stdint.h>
+#include "platform.h"
+#include "internals.h"
+#include "specialize.h"
+#include "softfloat.h"
+#include <iprt/types.h>
+#include <iprt/x86.h>
+
+extern const RTFLOAT128U g_r128pi2;
+
+extFloat80_t extF80_tan( extFloat80_t x SOFTFLOAT_STATE_DECL_COMMA )
+{
+    int32_t fSign = 0;
+    extFloat80_t v, f80Zero, f80One, f80Pi2;
+
+    f80Zero = ui32_to_extF80(0, pState);
+    f80One  = ui32_to_extF80(1, pState);
+    f80Pi2  = f128_to_extF80(*(float128_t *)&g_r128pi2, pState);
+
+    if (extF80_le(x, f80Zero, pState))
+    {
+        x = extF80_sub(f80Zero, x, pState);
+        fSign = 1;
+    }
+
+    uint16_t fCxFlags = 0;
+    extFloat80_t rem = extF80_partialRem(x, f80Pi2, pState->roundingMode, &fCxFlags, pState);
+    int32_t const quo = X86_FSW_CX_TO_QUOTIENT(fCxFlags);
+
+    v = extF80_div(rem, f80Pi2, pState);
+    v = extF80_mul(v, v, pState);
+    v = extF80_sub(f80One, v, pState);
+    v = extF80_div(rem, v, pState);
+
+    if (quo % 2)
+    {
+        v = extF80_div(f80One, v, pState);
+        v = extF80_sub(f80Zero, v, pState);
+    }
+
+    if (fSign)
+        v = extF80_sub(f80Zero, v, pState);
+
+    return v;
+}