1 files changed, 109 insertions, 0 deletions
diff --git a/src/math/__invtrigl.h b/src/math/__invtrigl.h
new file mode 100644
index 00000000..c3ad3c49
--- /dev/null
+++ b/src/math/__invtrigl.h
@@ -0,0 +1,109 @@
+/* origin: FreeBSD /usr/src/lib/msun/src/ld80/invtrig.h */
+/*-
+ * Copyright (c) 2008 David Schultz <das@FreeBSD.ORG>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include "libm.h"
+
+#if LDBL_MANT_DIG == 64 && LDBL_MAX_EXP == 16384
+
+#define BIAS            (LDBL_MAX_EXP - 1)
+#define MANH_SIZE       LDBL_MANH_SIZE
+
+/* Approximation thresholds. */
+#define ASIN_LINEAR     (BIAS - 32)     /* 2**-32 */
+#define ACOS_CONST      (BIAS - 65)     /* 2**-65 */
+#define ATAN_CONST      (BIAS + 65)     /* 2**65 */
+#define ATAN_LINEAR     (BIAS - 32)     /* 2**-32 */
+
+/* 0.95 */
+#define THRESH  ((0xe666666666666666ULL>>(64-(MANH_SIZE-1)))|LDBL_NBIT)
+
+/* Constants shared by the long double inverse trig functions. */
+#define pS0     __pS0
+#define pS1     __pS1
+#define pS2     __pS2
+#define pS3     __pS3
+#define pS4     __pS4
+#define pS5     __pS5
+#define pS6     __pS6
+#define qS1     __qS1
+#define qS2     __qS2
+#define qS3     __qS3
+#define qS4     __qS4
+#define qS5     __qS5
+#define atanhi  __atanhi
+#define atanlo  __atanlo
+#define aT      __aT
+#define pi_lo   __pi_lo
+
+#define pio2_hi atanhi[3]
+#define pio2_lo atanlo[3]
+#define pio4_hi atanhi[1]
+
+#ifdef STRUCT_DECLS
+typedef struct longdouble {
+	uint64_t mant;
+	uint16_t expsign;
+} LONGDOUBLE;
+#else
+typedef long double LONGDOUBLE;
+#endif
+
+extern const LONGDOUBLE pS0, pS1, pS2, pS3, pS4, pS5, pS6;
+extern const LONGDOUBLE qS1, qS2, qS3, qS4, qS5;
+extern const LONGDOUBLE atanhi[], atanlo[], aT[];
+extern const LONGDOUBLE pi_lo;
+
+#ifndef STRUCT_DECLS
+static inline long double
+P(long double x)
+{
+	return (x * (pS0 + x * (pS1 + x * (pS2 + x * (pS3 + x * \
+		(pS4 + x * (pS5 + x * pS6)))))));
+}
+
+static inline long double
+Q(long double x)
+{
+	return (1.0 + x * (qS1 + x * (qS2 + x * (qS3 + x * (qS4 + x * qS5)))));
+}
+
+static inline long double
+T_even(long double x)
+{
+	return (aT[0] + x * (aT[2] + x * (aT[4] + x * (aT[6] + x * \
+		(aT[8] + x * (aT[10] + x * aT[12]))))));
+}
+
+static inline long double
+T_odd(long double x)
+{
+	return (aT[1] + x * (aT[3] + x * (aT[5] + x * (aT[7] + x * \
+		(aT[9] + x * aT[11])))));
+}
+#endif
+
+#endif