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-rw-r--r--sysdeps/ieee754/dbl-64/s_fpclassify.c43
1 files changed, 43 insertions, 0 deletions
diff --git a/sysdeps/ieee754/dbl-64/s_fpclassify.c b/sysdeps/ieee754/dbl-64/s_fpclassify.c
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index 0000000000..72a15369b5
--- /dev/null
+++ b/sysdeps/ieee754/dbl-64/s_fpclassify.c
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+/* Return classification value corresponding to argument.
+   Copyright (C) 1997 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+
+   The GNU C Library 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include <math.h>
+
+#include "math_private.h"
+
+
+int
+__fpclassify (double x)
+{
+  u_int32_t hx, lx;
+  int retval = FP_NORMAL;
+
+  EXTRACT_WORDS (hx, lx, x);
+  lx |= hx & 0xfffff;
+  hx &= 0x7ff00000;
+  if ((hx | lx) == 0)
+    retval = FP_ZERO;
+  else if (hx == 0)
+    retval = FP_SUBNORMAL;
+  else if (hx == 0x7ff00000)
+    retval = lx != 0 ? FP_NAN : FP_INFINITE;
+
+  return retval;
+}