1 files changed, 103 insertions, 0 deletions
diff --git a/sysdeps/ieee754/ldbl-128/e_coshl.c b/sysdeps/ieee754/ldbl-128/e_coshl.c
new file mode 100644
index 0000000000..7ffc4d5159
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128/e_coshl.c
@@ -0,0 +1,103 @@
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+
+/* Changes for 128-bit long double contributed by
+   Stephen L. Moshier <moshier@na-net.ornl.gov> */
+
+/* __ieee754_coshl(x)
+ * Method :
+ * mathematically coshl(x) if defined to be (exp(x)+exp(-x))/2
+ *      1. Replace x by |x| (coshl(x) = coshl(-x)).
+ *      2.
+ *                                                      [ exp(x) - 1 ]^2
+ *          0        <= x <= ln2/2  :  coshl(x) := 1 + -------------------
+ *                                                         2*exp(x)
+ *
+ *                                                 exp(x) +  1/exp(x)
+ *          ln2/2    <= x <= 22     :  coshl(x) := -------------------
+ *                                                         2
+ *          22       <= x <= lnovft :  coshl(x) := expl(x)/2
+ *          lnovft   <= x <= ln2ovft:  coshl(x) := expl(x/2)/2 * expl(x/2)
+ *          ln2ovft  <  x           :  coshl(x) := huge*huge (overflow)
+ *
+ * Special cases:
+ *      coshl(x) is |x| if x is +INF, -INF, or NaN.
+ *      only coshl(0)=1 is exact for finite x.
+ */
+
+#include "math.h"
+#include "math_private.h"
+
+#ifdef __STDC__
+static const long double one = 1.0, half = 0.5, huge = 1.0e4900L,
+ovf_thresh = 1.1357216553474703894801348310092223067821E4L;
+#else
+static long double one = 1.0, half = 0.5, huge = 1.0e4900L,
+ovf_thresh = 1.1357216553474703894801348310092223067821E4L;
+#endif
+
+#ifdef __STDC__
+long double
+__ieee754_coshl (long double x)
+#else
+long double
+__ieee754_coshl (x)
+     long double x;
+#endif
+{
+  long double t, w;
+  int32_t ex;
+  u_int32_t mx, lx;
+  ieee854_long_double_shape_type u;
+
+  u.value = x;
+  ex = u.parts32.w0 & 0x7fffffff;
+
+  /* Absolute value of x.  */
+  u.parts32.w0 = ex;
+
+  /* x is INF or NaN */
+  if (ex >= 0x7fff0000)
+    return x * x;
+
+  /* |x| in [0,0.5*ln2], return 1+expm1l(|x|)^2/(2*expl(|x|)) */
+  if (ex < 0x3ffd62e4) /* 0.3465728759765625 */
+    {
+      t = __expm1l (u.value);
+      w = one + t;
+      if (ex < 0x3fc60000) /* |x| < 2^-57 */
+	return w;		/* cosh(tiny) = 1 */
+
+      return one + (t * t) / (w + w);
+    }
+
+  /* |x| in [0.5*ln2,40], return (exp(|x|)+1/exp(|x|)/2; */
+  if (ex < 0x40044000)
+    {
+      t = __ieee754_expl (u.value);
+      return half * t + half / t;
+    }
+
+  /* |x| in [22, ln(maxdouble)] return half*exp(|x|) */
+  if (ex <= 0x400c62e3) /* 11356.375 */
+    return half * __ieee754_expl (u.value);
+
+  /* |x| in [log(maxdouble), overflowthresold] */
+  if (u.value <= ovf_thresh)
+    {
+      w = __ieee754_expl (half * u.value);
+      t = half * w;
+      return t * w;
+    }
+
+  /* |x| > overflowthresold, cosh(x) overflow */
+  return huge * huge;
+}