From 277bd9826cebcc6fde7e6fd8c0afbe5638768961 Mon Sep 17 00:00:00 2001
From: Bruno Haible <bruno@clisp.org>
Date: Thu, 22 Mar 2007 12:24:07 +0000
Subject: [PATCH] Merge the frexpl and frexp implementations into a single
 code.

---
 ChangeLog     |  6 ++++
 lib/frexpl.c  | 96 +++--------------------------------------------------------
 modules/mathl |  2 ++
 3 files changed, 12 insertions(+), 92 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index d71b878f5..0cd2fab77 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,11 @@
 2007-03-22  Bruno Haible  <bruno@clisp.org>
 
+	* lib/frexpl.c: Share code with lib/frexp.c.
+	* modules/mathl (Files): Add lib/frexp.c.
+	(Depends-on): Add isnanl-nolibm.
+
+2007-03-22  Bruno Haible  <bruno@clisp.org>
+
 	* modules/printf-frexp (Files): Add m4/frexp.m4.
 	* m4/printf-frexp.m4 (gl_FUNC_PRINTF_FREXP): Define HAVE_FREXP_IN_LIBC
 	only if the found frexp function actually works.
diff --git a/lib/frexpl.c b/lib/frexpl.c
index f78c4000d..75852ba62 100644
--- a/lib/frexpl.c
+++ b/lib/frexpl.c
@@ -1,9 +1,5 @@
-/* Emulation for frexpl.
-   Contributed by Paolo Bonzini
-
-   Copyright 2002, 2003, 2007 Free Software Foundation, Inc.
-
-   This file is part of gnulib.
+/* Split a 'long double' into fraction and mantissa.
+   Copyright (C) 2007 Free Software Foundation, Inc.
 
    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
@@ -19,89 +15,5 @@
    with this program; if not, write to the Free Software Foundation,
    Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
 
-#include <config.h>
-
-/* Specification.  */
-#include <math.h>
-
-#include <float.h>
-
-/* Binary search.  Quite inefficient but portable. */
-long double
-frexpl(long double x, int *exp)
-{
-  /* Since the exponent is an 'int', it fits in 64 bits.  Therefore the
-     loops are executed no more than 64 times.  */
-  long double exponents[64];
-  long double *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;
-	  }
-
-      exponent = -exponent;
-    }
-
-  *exp = exponent;
-  return x;
-}
-
-#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(1.0L, &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
-
+#define USE_LONG_DOUBLE
+#include "frexp.c"
diff --git a/modules/mathl b/modules/mathl
index b75eeca8a..4a7c5953d 100644
--- a/modules/mathl
+++ b/modules/mathl
@@ -10,6 +10,7 @@ lib/cosl.c
 lib/expl.c
 lib/floorl.c
 lib/frexpl.c
+lib/frexp.c
 lib/ldexpl.c
 lib/logl.c
 lib/sincosl.c
@@ -22,6 +23,7 @@ m4/mathl.m4
 
 Depends-on:
 math
+isnanl-nolibm
 
 configure.ac:
 gl_FUNC_LONG_DOUBLE_MATH
-- 
2.11.0