-/* Emulation for frexpl.
- Contributed by Paolo Bonzini
+/* Split a 'long double' into fraction and mantissa.
+ Copyright (C) 2007, 2009-2014 Free Software Foundation, Inc.
- Copyright 2002, 2003 Free Software Foundation, Inc.
-
- This file is part of gnulib.
-
- This program is free software; you can redistribute it and/or modify
+ 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 2, or (at your option)
- any later version.
+ 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, write to the Free Software Foundation,
- Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
+ 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 <float.h>
-#include <math.h>
+#include <config.h>
-#include "mathl.h"
+#if HAVE_SAME_LONG_DOUBLE_AS_DOUBLE
+
+/* Specification. */
+# include <math.h>
-/* Binary search. Quite inefficient but portable. */
long double
-frexpl(long double x, int *exp)
+frexpl (long double x, int *expptr)
{
- long double exponents[20], *next;
- int exponent, bit;
-
- /* Check for zero, nan and infinity. */
- if (x != x || x + x == x )
- {
- *exp = 0;
- return x;
- }
-
- if (x < 0)
- return -frexpl(-x, exp);
-
- exponent = 0;
- if (x > 1.0)
- {
- for (next = exponents, exponents[0] = 2.0L, bit = 1;
- *next <= x + x;
- bit <<= 1, next[1] = next[0] * next[0], next++);
-
- for (; next >= exponents; bit >>= 1, next--)
- if (x + x >= *next)
- {
- x /= *next;
- exponent |= bit;
- }
-
- }
-
- else if (x < 0.5)
- {
- for (next = exponents, exponents[0] = 0.5L, bit = 1;
- *next > x;
- bit <<= 1, next[1] = next[0] * next[0], next++);
-
- for (; next >= exponents; bit >>= 1, next--)
- if (x < *next)
- {
- x /= *next;
- exponent |= bit;
- }
+ return frexp (x, expptr);
+}
- exponent = -exponent;
- }
+#else
- *exp = exponent;
- return x;
-}
+# define USE_LONG_DOUBLE
+# include "frexp.c"
-#if 0
-int
-main (void)
-{
- long double x;
- int y;
- x = frexpl(0.0L / 0.0L, &y); printf ("%.6Lg %d\n", x, y);
- x = frexpl(1.0L / 0.0L, &y); printf ("%.6Lg %d\n", x, y);
- x = frexpl(-1.0L / 0.0L, &y); printf ("%.6Lg %d\n", x, y);
- x = frexpl(0.5L, &y); printf ("%.6Lg %d\n", x, y);
- x = frexpl(0.75L, &y); printf ("%.6Lg %d\n", x, y);
- x = frexpl(3.6L, &y); printf ("%.6Lg %d\n", x, y);
- x = frexpl(17.8L, &y); printf ("%.6Lg %d\n", x, y);
- x = frexpl(8.0L, &y); printf ("%.6Lg %d\n", x, y);
- x = frexpl(0.3L, &y); printf ("%.6Lg %d\n", x, y);
- x = frexpl(0.49L, &y); printf ("%.6Lg %d\n", x, y);
- x = frexpl(0.049L, &y); printf ("%.6Lg %d\n", x, y);
- x = frexpl(0.0245L, &y); printf ("%.6Lg %d\n", x, y);
- x = frexpl(0.0625L, &y); printf ("%.6Lg %d\n", x, y);
-}
#endif
-