Meta: Add OpenLibm

src/openlibm/ld80/s_asinhl.c

@@ -0,0 +1,54 @@
+/* @(#)s_asinh.c 5.1 93/09/24 */
+/*
+ * ====================================================
+ * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+ *
+ * Developed at SunPro, a Sun Microsystems, Inc. business.
+ * Permission to use, copy, modify, and distribute this
+ * software is freely granted, provided that this notice
+ * is preserved.
+ * ====================================================
+ */
+
+/* asinhl(x)
+ * Method :
+ *	Based on
+ *		asinhl(x) = signl(x) * logl [ |x| + sqrtl(x*x+1) ]
+ *	we have
+ *	asinhl(x) := x  if  1+x*x=1,
+ *		  := signl(x)*(logl(x)+ln2)) for large |x|, else
+ *		  := signl(x)*logl(2|x|+1/(|x|+sqrtl(x*x+1))) if|x|>2, else
+ *		  := signl(x)*log1pl(|x| + x^2/(1 + sqrtl(1+x^2)))
+ */
+
+#include <openlibm_math.h>
+
+#include "math_private.h"
+
+static const long double
+one =  1.000000000000000000000e+00L, /* 0x3FFF, 0x00000000, 0x00000000 */
+ln2 =  6.931471805599453094287e-01L, /* 0x3FFE, 0xB17217F7, 0xD1CF79AC */
+huge=  1.000000000000000000e+4900L;
+
+long double
+asinhl(long double x)
+{
+	long double t,w;
+	int32_t hx,ix;
+	GET_LDOUBLE_EXP(hx,x);
+	ix = hx&0x7fff;
+	if(ix==0x7fff) return x+x;	/* x is inf or NaN */
+	if(ix< 0x3fde) {	/* |x|<2**-34 */
+	    if(huge+x>one) return x;	/* return x inexact except 0 */
+	}
+	if(ix>0x4020) {		/* |x| > 2**34 */
+	    w = logl(fabsl(x))+ln2;
+	} else if (ix>0x4000) {	/* 2**34 > |x| > 2.0 */
+	    t = fabsl(x);
+	    w = logl(2.0*t+one/(sqrtl(x*x+one)+t));
+	} else {		/* 2.0 > |x| > 2**-28 */
+	    t = x*x;
+	    w =log1pl(fabsl(x)+t/(one+sqrtl(one+t)));
+	}
+	if(hx&0x8000) return -w; else return w;
+}