2 files changed, 147 insertions, 0 deletions
diff --git a/gnulib b/gnulib
deleted file mode 160000
-Subproject 443bc5ffcf7429e557f4a371b0661abe98ddbc1
diff --git a/gnulib/lib/expl.c b/gnulib/lib/expl.c
new file mode 100644
index 0000000..49fdefa
--- /dev/null
+++ b/gnulib/lib/expl.c
@@ -0,0 +1,147 @@
+/* Emulation for expl.
+   Contributed by Paolo Bonzini
+
+   Copyright 2002-2003, 2007, 2009-2011 Free Software Foundation, Inc.
+
+   This file is part of gnulib.
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include <config.h>
+
+/* Specification.  */
+#include <math.h>
+
+#if HAVE_SAME_LONG_DOUBLE_AS_DOUBLE
+
+long double
+expl (long double x)
+{
+  return exp (x);
+}
+
+#else
+
+# include <float.h>
+
+static const long double C[] = {
+/* Chebyshev polynom coeficients for (exp(x)-1)/x */
+# define P1 C[0]
+# define P2 C[1]
+# define P3 C[2]
+# define P4 C[3]
+# define P5 C[4]
+# define P6 C[5]
+ 0.5L,
+ 1.66666666666666666666666666666666683E-01L,
+ 4.16666666666666666666654902320001674E-02L,
+ 8.33333333333333333333314659767198461E-03L,
+ 1.38888888889899438565058018857254025E-03L,
+ 1.98412698413981650382436541785404286E-04L,
+
+/* Smallest integer x for which e^x overflows.  */
+# define himark C[6]
+ 11356.523406294143949491931077970765L,
+
+/* Largest integer x for which e^x underflows.  */
+# define lomark C[7]
+-11433.4627433362978788372438434526231L,
+
+/* very small number */
+# define TINY C[8]
+ 1.0e-4900L,
+
+/* 2^16383 */
+# define TWO16383 C[9]
+ 5.94865747678615882542879663314003565E+4931L};
+
+long double
+expl (long double x)
+{
+  /* Check for usual case.  */
+  if (x < himark && x > lomark)
+    {
+      int exponent;
+      long double t, x22;
+      int k = 1;
+      long double result = 1.0;
+
+      /* Compute an integer power of e with a granularity of 0.125.  */
+      exponent = (int) floorl (x * 8.0L);
+      x -= exponent / 8.0L;
+
+      if (x > 0.0625)
+        {
+          exponent++;
+          x -= 0.125L;
+        }
+
+      if (exponent < 0)
+        {
+          t = 0.8824969025845954028648921432290507362220L; /* e^-0.25 */
+          exponent = -exponent;
+        }
+      else
+        t = 1.1331484530668263168290072278117938725655L; /* e^0.25 */
+
+      while (exponent)
+        {
+          if (exponent & k)
+            {
+              result *= t;
+              exponent ^= k;
+            }
+          t *= t;
+          k <<= 1;
+        }
+
+      /* Approximate (e^x - 1)/x, using a seventh-degree polynomial,
+         with maximum error in [-2^-16-2^-53,2^-16+2^-53]
+         less than 4.8e-39.  */
+      x22 = x + x*x*(P1+x*(P2+x*(P3+x*(P4+x*(P5+x*P6)))));
+
+      return result + result * x22;
+    }
+  /* Exceptional cases:  */
+  else if (x < himark)
+    {
+      if (x + x == x)
+        /* e^-inf == 0, with no error.  */
+        return 0;
+      else
+        /* Underflow */
+        return TINY * TINY;
+    }
+  else
+    /* Return x, if x is a NaN or Inf; or overflow, otherwise.  */
+    return TWO16383*x;
+}
+
+#endif
+
+#if 0
+int
+main (void)
+{
+  printf ("%.16Lg\n", expl (1.0L));
+  printf ("%.16Lg\n", expl (-1.0L));
+  printf ("%.16Lg\n", expl (2.0L));
+  printf ("%.16Lg\n", expl (4.0L));
+  printf ("%.16Lg\n", expl (-2.0L));
+  printf ("%.16Lg\n", expl (-4.0L));
+  printf ("%.16Lg\n", expl (0.0625L));
+  printf ("%.16Lg\n", expl (0.3L));
+  printf ("%.16Lg\n", expl (0.6L));
+}
+#endif