-/* origin: OpenBSD /usr/src/lib/libm/src/ld80/e_acoshl.c */
-/*
- * ====================================================
- * 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.
- * ====================================================
- */
-/* acoshl(x)
- * Method :
- * Based on
- * acoshl(x) = logl [ x + sqrtl(x*x-1) ]
- * we have
- * acoshl(x) := logl(x)+ln2, if x is large; else
- * acoshl(x) := logl(2x-1/(sqrtl(x*x-1)+x)) if x>2; else
- * acoshl(x) := log1pl(t+sqrtl(2.0*t+t*t)); where t=x-1.
- *
- * Special cases:
- * acoshl(x) is NaN with signal if x<1.
- * acoshl(NaN) is NaN without signal.
- */
-