summaryrefslogtreecommitdiff
path: root/libquadmath/math/asinhq.c
diff options
context:
space:
mode:
Diffstat (limited to 'libquadmath/math/asinhq.c')
-rw-r--r--libquadmath/math/asinhq.c71
1 files changed, 71 insertions, 0 deletions
diff --git a/libquadmath/math/asinhq.c b/libquadmath/math/asinhq.c
new file mode 100644
index 000000000..be044dcd8
--- /dev/null
+++ b/libquadmath/math/asinhq.c
@@ -0,0 +1,71 @@
+/* s_asinhl.c -- long double version of s_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.
+ * ====================================================
+ */
+
+/* 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 "quadmath-imp.h"
+
+static const __float128
+ one = 1.0Q,
+ ln2 = 6.931471805599453094172321214581765681e-1Q,
+ huge = 1.0e+4900Q;
+
+__float128
+asinhq (__float128 x)
+{
+ __float128 t, w;
+ int32_t ix, sign;
+ ieee854_float128 u;
+
+ u.value = x;
+ sign = u.words32.w0;
+ ix = sign & 0x7fffffff;
+ if (ix == 0x7fff0000)
+ return x + x; /* x is inf or NaN */
+ if (ix < 0x3fc70000)
+ { /* |x| < 2^ -56 */
+ if (huge + x > one)
+ return x; /* return x inexact except 0 */
+ }
+ u.words32.w0 = ix;
+ if (ix > 0x40350000)
+ { /* |x| > 2 ^ 54 */
+ w = logq (u.value) + ln2;
+ }
+ else if (ix >0x40000000)
+ { /* 2^ 54 > |x| > 2.0 */
+ t = u.value;
+ w = logq (2.0 * t + one / (sqrtq (x * x + one) + t));
+ }
+ else
+ { /* 2.0 > |x| > 2 ^ -56 */
+ t = x * x;
+ w = log1pq (u.value + t / (one + sqrtq (one + t)));
+ }
+ if (sign & 0x80000000)
+ return -w;
+ else
+ return w;
+}