1 files changed, 78 insertions, 0 deletions
diff --git a/lib/libm/__invtrigl.c b/lib/libm/__invtrigl.c
new file mode 100644
index 00000000..66e4c7eb
--- /dev/null
+++ b/lib/libm/__invtrigl.c
@@ -0,0 +1,78 @@
+#include <float.h>
+#include "__invtrigl.h"
+
+#if LDBL_MANT_DIG == 64 && LDBL_MAX_EXP == 16384
+static const long double pS0 = 1.66666666666666666631e-01L,
+			 pS1 = -4.16313987993683104320e-01L,
+			 pS2 = 3.69068046323246813704e-01L,
+			 pS3 = -1.36213932016738603108e-01L,
+			 pS4 = 1.78324189708471965733e-02L,
+			 pS5 = -2.19216428382605211588e-04L,
+			 pS6 = -7.10526623669075243183e-06L,
+			 qS1 = -2.94788392796209867269e+00L,
+			 qS2 = 3.27309890266528636716e+00L,
+			 qS3 = -1.68285799854822427013e+00L,
+			 qS4 = 3.90699412641738801874e-01L,
+			 qS5 = -3.14365703596053263322e-02L;
+
+const long double pio2_hi = 1.57079632679489661926L;
+const long double pio2_lo = -2.50827880633416601173e-20L;
+
+/* used in asinl() and acosl() */
+/* R(x^2) is a rational approximation of (asin(x)-x)/x^3 with Remez algorithm */
+long double __invtrigl_R(long double z)
+{
+	long double p, q;
+	p = z * (pS0 +
+		 z * (pS1 +
+		      z * (pS2 + z * (pS3 + z * (pS4 + z * (pS5 + z * pS6))))));
+	q = 1.0 + z * (qS1 + z * (qS2 + z * (qS3 + z * (qS4 + z * qS5))));
+	return p / q;
+}
+#elif LDBL_MANT_DIG == 113 && LDBL_MAX_EXP == 16384
+static const long double pS0 = 1.66666666666666666666666666666700314e-01L,
+			 pS1 = -7.32816946414566252574527475428622708e-01L,
+			 pS2 = 1.34215708714992334609030036562143589e+00L,
+			 pS3 = -1.32483151677116409805070261790752040e+00L,
+			 pS4 = 7.61206183613632558824485341162121989e-01L,
+			 pS5 = -2.56165783329023486777386833928147375e-01L,
+			 pS6 = 4.80718586374448793411019434585413855e-02L,
+			 pS7 = -4.42523267167024279410230886239774718e-03L,
+			 pS8 = 1.44551535183911458253205638280410064e-04L,
+			 pS9 = -2.10558957916600254061591040482706179e-07L,
+			 qS1 = -4.84690167848739751544716485245697428e+00L,
+			 qS2 = 9.96619113536172610135016921140206980e+00L,
+			 qS3 = -1.13177895428973036660836798461641458e+01L,
+			 qS4 = 7.74004374389488266169304117714658761e+00L,
+			 qS5 = -3.25871986053534084709023539900339905e+00L,
+			 qS6 = 8.27830318881232209752469022352928864e-01L,
+			 qS7 = -1.18768052702942805423330715206348004e-01L,
+			 qS8 = 8.32600764660522313269101537926539470e-03L,
+			 qS9 = -1.99407384882605586705979504567947007e-04L;
+
+const long double pio2_hi = 1.57079632679489661923132169163975140L;
+const long double pio2_lo = 4.33590506506189051239852201302167613e-35L;
+
+long double __invtrigl_R(long double z)
+{
+	long double p, q;
+	p = z * (pS0 +
+		 z * (pS1 +
+		      z * (pS2 +
+			   z * (pS3 +
+				z * (pS4 +
+				     z * (pS5 +
+					  z * (pS6 +
+					       z * (pS7 +
+						    z * (pS8 + z * pS9)))))))));
+	q = 1.0 +
+	    z * (qS1 +
+		 z * (qS2 +
+		      z * (qS3 +
+			   z * (qS4 +
+				z * (qS5 +
+				     z * (qS6 +
+					  z * (qS7 + z * (qS8 + z * qS9))))))));
+	return p / q;
+}
+#endif