newlib/libm/common/s_nearbyint.c

   1 /*
   2  * ====================================================
   3  * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
   4  *
   5  * Developed at SunPro, a Sun Microsystems, Inc. business.
   6  * Permission to use, copy, modify, and distribute this
   7  * software is freely granted, provided that this notice
   8  * is preserved.
   9  * ====================================================
  10  */
  11 /*
  12 FUNCTION
  13 <<nearbyint>>, <<nearbyintf>>---round to integer
  14 INDEX
  15         nearbyint
  16 INDEX
  17         nearbyintf
  18
  19 SYNOPSIS
  20         #include <math.h>
  21         double nearbyint(double <[x]>);
  22         float nearbyintf(float <[x]>);
  23
  24 DESCRIPTION
  25 The <<nearbyint>> functions round their argument to an integer value in
  26 floating-point format, using the current rounding direction and
  27 (supposedly) without raising the "inexact" floating-point exception.
  28 See the <<rint>> functions for the same function with the "inexact"
  29 floating-point exception being raised when appropriate.
  30
  31 BUGS
  32 Newlib does not support the floating-point exception model, so that
  33 the floating-point exception control is not present and thereby what may
  34 be seen will be compiler and hardware dependent in this regard.
  35 The Newlib <<nearbyint>> functions are identical to the <<rint>>
  36 functions with respect to the floating-point exception behavior, and
  37 will cause the "inexact" exception to be raised for most targets.
  38
  39 RETURNS
  40 <[x]> rounded to an integral value, using the current rounding direction.
  41
  42 PORTABILITY
  43 ANSI C, POSIX
  44
  45 SEEALSO
  46 <<rint>>, <<round>>
  47 */
  48
  49 #include <math.h>
  50 #include "fdlibm.h"
  51
  52 #ifndef _DOUBLE_IS_32BITS
  53
  54 #ifdef __STDC__
  55         double nearbyint(double x)
  56 #else
  57         double nearbyint(x)
  58         double x;
  59 #endif
  60 {
  61   return rint(x);
  62 }
  63
  64 #endif /* _DOUBLE_IS_32BITS */