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-rw-r--r--src/math/asinhl.c63
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diff --git a/src/math/asinhl.c b/src/math/asinhl.c
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+/* origin: OpenBSD /usr/src/lib/libm/src/ld80/s_asinhl.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.
+ * ====================================================
+ */
+/* 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 "libm.h"
+
+#if LDBL_MANT_DIG == 53 && LDBL_MAX_EXP == 1024
+long double asinhl(long double x)
+{
+ return asinh(x);
+}
+#elif LDBL_MANT_DIG == 64 && LDBL_MAX_EXP == 16384
+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 */
+ /* return x, raise inexact if x != 0 */
+ if (huge+x > one)
+ return x;
+ }
+ 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;
+ return w;
+}
+#endif