ceill.c

/******************************** -*- C -*- ****************************
 *
 *	Emulation for ceill
 *
 *
 ***********************************************************************/

/***********************************************************************
 *
 * Copyright 2002, 2006 Free Software Foundation, Inc.
 * Written by Paolo Bonzini.
 *
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 ***********************************************************************/

#include <float.h>

#include "mathl.h"

/* To compute the integer part of X, sum a big enough
   integer so that the precision of the floating point
   number is exactly 1.  */

long double
ceill(long double x)
{
  long double y;
  if (x < 0.0L)
    y = -(1.0L / LDBL_EPSILON - x - 1.0 / LDBL_EPSILON);
  else
    y = 1.0L / LDBL_EPSILON + x - 1.0 / LDBL_EPSILON;

  if (y < x)
    return y + 1.0L;
  else
    return y;
}