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-rw-r--r--sysdeps/libm-ieee754/e_sinhl.c91
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diff --git a/sysdeps/libm-ieee754/e_sinhl.c b/sysdeps/libm-ieee754/e_sinhl.c
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+/* e_asinhl.c -- long double version of e_asinh.c.
+ * Conversion to long double by Ulrich Drepper,
+ * Cygnus Support, drepper@cygnus.com.
+ */
+
+/*
+ * ====================================================
+ * 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: $";
+#endif
+
+/* __ieee754_sinhl(x)
+ * Method :
+ * mathematically sinh(x) if defined to be (exp(x)-exp(-x))/2
+ *	1. Replace x by |x| (sinhl(-x) = -sinhl(x)).
+ *	2.
+ *		                                     E + E/(E+1)
+ *	    0        <= x <= 25     :  sinhl(x) := --------------, E=expm1l(x)
+ *			       			         2
+ *
+ *	    25       <= x <= lnovft :  sinhl(x) := expl(x)/2
+ *	    lnovft   <= x <= ln2ovft:  sinhl(x) := expl(x/2)/2 * expl(x/2)
+ *	    ln2ovft  <  x	    :  sinhl(x) := x*shuge (overflow)
+ *
+ * Special cases:
+ *	sinhl(x) is |x| if x is +INF, -INF, or NaN.
+ *	only sinhl(0)=0 is exact for finite x.
+ */
+
+#include "math.h"
+#include "math_private.h"
+
+#ifdef __STDC__
+static const long double one = 1.0, shuge = 1.0e4931L;
+#else
+static long double one = 1.0, shuge = 1.0e4931L;
+#endif
+
+#ifdef __STDC__
+	long double __ieee754_sinhl(long double x)
+#else
+	long double __ieee754_sinhl(x)
+	long double x;
+#endif
+{
+	long double t,w,h;
+	u_int32_t jx,ix,i0,i1;
+
+    /* Words of |x|. */
+	GET_LDOUBLE_WORDS(jx,i0,i1,x);
+	ix = jx&0x7fff;
+
+    /* x is INF or NaN */
+	if(ix==0x7fff) return x+x;
+
+	h = 0.5;
+	if (jx<0) h = -h;
+    /* |x| in [0,25], return sign(x)*0.5*(E+E/(E+1))) */
+	if (ix < 0x4003 || (ix == 0x4003 && i0 <= 0xc8000000)) { /* |x|<25 */
+	    if (ix<0x3fe3) 		/* |x|<2**-28 */
+		if(shuge+x>one) return x;/* sinh(tiny) = tiny with inexact */
+	    t = __expm1l(fabsl(x));
+	    if(ix<0x3fff) return h*(2.0*t-t*t/(t+one));
+	    return h*(t+t/(t+one));
+	}
+
+    /* |x| in [25, log(maxdouble)] return 0.5*exp(|x|) */
+	if (ix < 0x400c || (ix == 0x400c && i0 < 0xb17217f7))
+		return h*__ieee754_expl(fabsl(x));
+
+    /* |x| in [log(maxdouble), overflowthresold] */
+	if (ix<0x400c || (ix == 0x400c && (i0 < 0xb174ddc0
+					   || (i0 == 0xb174ddc0
+					       && i1 <= 0x31aec0ea)))) {
+	    w = __ieee754_expl(0.5*fabsl(x));
+	    t = h*w;
+	    return t*w;
+	}
+
+    /* |x| > overflowthresold, sinhl(x) overflow */
+	return x*shuge;
+}