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-rw-r--r--sysdeps/libm-ieee754/s_truncf.c52
1 files changed, 52 insertions, 0 deletions
diff --git a/sysdeps/libm-ieee754/s_truncf.c b/sysdeps/libm-ieee754/s_truncf.c
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+++ b/sysdeps/libm-ieee754/s_truncf.c
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+/* Truncate argument to nearest integral value not larger than the 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"
+
+
+float
+__truncf (float x)
+{
+  int32_t i0, j0;
+  int sx;
+
+  GET_FLOAT_WORD (i0, x);
+  sx = i0 & 0x80000000;
+  j0 = ((i0 >> 23) & 0xff) - 0x7f;
+  if (j0 < 23)
+    {
+      if (j0 < 0)
+	/* The magnitude of the number is < 1 so the result is +-0.  */
+	SET_FLOAT_WORD (x, sx);
+      else
+	SET_FLOAT_WORD (x, sx | i0 & ~(0x007fffff >> j0));
+    }
+  else
+    {
+      if (j0 == 0x80)
+	/* x is inf or NaN.  */
+	return x + x;
+    }
+
+  return x;
+}
+weak_alias (__truncf, truncf)