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Diffstat (limited to 'sysdeps/ieee754/ldbl-128ibm/s_asinhl.c')
-rw-r--r--sysdeps/ieee754/ldbl-128ibm/s_asinhl.c67
1 files changed, 67 insertions, 0 deletions
diff --git a/sysdeps/ieee754/ldbl-128ibm/s_asinhl.c b/sysdeps/ieee754/ldbl-128ibm/s_asinhl.c
new file mode 100644
index 0000000000..d1b63bb909
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128ibm/s_asinhl.c
@@ -0,0 +1,67 @@
+/* @(#)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.
+ * ====================================================
+ */
+
+#if defined(LIBM_SCCS) && !defined(lint)
+static char rcsid[] = "$NetBSD: s_asinh.c,v 1.9 1995/05/12 04:57:37 jtc Exp $";
+#endif
+
+/* asinh(x)
+ * Method :
+ *	Based on
+ *		asinh(x) = sign(x) * log [ |x| + sqrt(x*x+1) ]
+ *	we have
+ *	asinh(x) := x  if  1+x*x=1,
+ *		 := sign(x)*(log(x)+ln2)) for large |x|, else
+ *		 := sign(x)*log(2|x|+1/(|x|+sqrt(x*x+1))) if|x|>2, else
+ *		 := sign(x)*log1p(|x| + x^2/(1 + sqrt(1+x^2)))
+ */
+
+#include "math.h"
+#include "math_private.h"
+#include <math_ldbl_opt.h>
+
+#ifdef __STDC__
+static const long double
+#else
+static long double
+#endif
+one =  1.00000000000000000000e+00L, /* 0x3ff0000000000000, 0 */
+ln2 =  0.6931471805599453094172321214581766L, /* 0x3fe62e42fefa39ef, 0x3c7abc9e3b398040 */
+huge=  1.00000000000000000000e+300L;
+
+#ifdef __STDC__
+	long double __asinhl(long double x)
+#else
+	long double __asinhl(x)
+	long double x;
+#endif
+{
+	long double t,w;
+	int64_t hx,ix;
+	GET_LDOUBLE_MSW64(hx,x);
+	ix = hx&0x7fffffffffffffffLL;
+	if(ix>=0x7ff0000000000000LL) return x+x;	/* x is inf or NaN */
+	if(ix< 0x3e20000000000000LL) {	/* |x|<2**-29 */
+	    if(huge+x>one) return x;	/* return x inexact except 0 */
+	}
+	if(ix>0x41b0000000000000LL) {	/* |x| > 2**28 */
+	    w = __ieee754_logl(fabs(x))+ln2;
+	} else if (ix>0x4000000000000000LL) {	/* 2**28 > |x| > 2.0 */
+	    t = fabs(x);
+	    w = __ieee754_logl(2.0*t+one/(__ieee754_sqrtl(x*x+one)+t));
+	} else {		/* 2.0 > |x| > 2**-29 */
+	    t = x*x;
+	    w =__log1pl(fabsl(x)+t/(one+__ieee754_sqrtl(one+t)));
+	}
+	if(hx>0) return w; else return -w;
+}
+long_double_symbol (libm, __asinhl, asinhl);