1 files changed, 80 insertions, 0 deletions
diff --git a/src/math/asinl.c b/src/math/asinl.c
new file mode 100644
index 00000000..370997bc
--- /dev/null
+++ b/src/math/asinl.c
@@ -0,0 +1,80 @@
+/* origin: FreeBSD /usr/src/lib/msun/src/e_asinl.c */
+/*
+ * ====================================================
+ * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+ *
+ * Developed at SunSoft, a Sun Microsystems, Inc. business.
+ * Permission to use, copy, modify, and distribute this
+ * software is freely granted, provided that this notice
+ * is preserved.
+ * ====================================================
+ */
+/*
+ * See comments in asin.c.
+ * Converted to long double by David Schultz <das@FreeBSD.ORG>.
+ */
+
+#include "libm.h"
+
+#if LDBL_MANT_DIG == 53 && LDBL_MAX_EXP == 1024
+long double asinl(long double x)
+{
+	return asin(x);
+}
+#elif (LDBL_MANT_DIG == 64 || LDBL_MANT_DIG == 113) && LDBL_MAX_EXP == 16384
+#include "__invtrigl.h"
+static const long double
+one = 1.00000000000000000000e+00,
+huge = 1.000e+300;
+
+long double asinl(long double x)
+{
+	union IEEEl2bits u;
+	long double t=0.0,w,p,q,c,r,s;
+	int16_t expsign, expt;
+
+	u.e = x;
+	expsign = u.xbits.expsign;
+	expt = expsign & 0x7fff;
+	if (expt >= BIAS) {          /* |x|>= 1 */
+		if (expt == BIAS &&
+		    ((u.bits.manh&~LDBL_NBIT)|u.bits.manl) == 0)
+			/* asin(1)=+-pi/2 with inexact */
+			return x*pio2_hi + x*pio2_lo;
+		return (x-x)/(x-x);  /* asin(|x|>1) is NaN */
+	} else if (expt < BIAS-1) {  /* |x|<0.5 */
+		if (expt < ASIN_LINEAR) {  /* if |x| is small, asinl(x)=x */
+			/* return x with inexact if x!=0 */
+			if (huge+x > one)
+				return x;
+		}
+		t = x*x;
+		p = P(t);
+		q = Q(t);
+		w = p/q;
+		return x + x*w;
+	}
+	/* 1 > |x| >= 0.5 */
+	w = one - fabsl(x);
+	t = w*0.5;
+	p = P(t);
+	q = Q(t);
+	s = sqrtl(t);
+	if (u.bits.manh >= THRESH) { /* if |x| is close to 1 */
+		w = p/q;
+		t = pio2_hi-(2.0*(s+s*w)-pio2_lo);
+	} else {
+		u.e = s;
+		u.bits.manl = 0;
+		w = u.e;
+		c = (t-w*w)/(s+w);
+		r = p/q;
+		p = 2.0*s*r-(pio2_lo-2.0*c);
+		q = pio4_hi-2.0*w;
+		t = pio4_hi-(p-q);
+	}
+	if (expsign > 0)
+		return t;
+	return -t;
+}
+#endif