1  /* s_rintf.c -- float version of s_rint.c.
       2   */
       3  
       4  /*
       5   * ====================================================
       6   * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
       7   *
       8   * Developed at SunPro, a Sun Microsystems, Inc. business.
       9   * Permission to use, copy, modify, and distribute this
      10   * software is freely granted, provided that this notice
      11   * is preserved.
      12   * ====================================================
      13   */
      14  
      15  #define NO_MATH_REDIRECT
      16  #include <math.h>
      17  #include <math_private.h>
      18  #include <libm-alias-float.h>
      19  #include <math-use-builtins.h>
      20  
      21  float
      22  __rintf (float x)
      23  {
      24  #if USE_RINTF_BUILTIN
      25    return __builtin_rintf (x);
      26  #else
      27    /* Use generic implementation.  */
      28    static const float
      29      TWO23[2] = {
      30  		8.3886080000e+06, /* 0x4b000000 */
      31  		-8.3886080000e+06, /* 0xcb000000 */
      32    };
      33    int32_t i0, j0, sx;
      34    float w, t;
      35    GET_FLOAT_WORD (i0, x);
      36    sx = (i0 >> 31) & 1;
      37    j0 = ((i0 >> 23) & 0xff) - 0x7f;
      38    if (j0 < 23)
      39      {
      40        if(j0 < 0)
      41  	{
      42  	  w = TWO23[sx] + x;
      43  	  t =  w - TWO23[sx];
      44  	  GET_FLOAT_WORD (i0, t);
      45  	  SET_FLOAT_WORD (t, (i0 & 0x7fffffff) | (sx << 31));
      46  	  return t;
      47  	}
      48      }
      49    else
      50      {
      51        if (j0 == 0x80)
      52  	return x + x;		/* inf or NaN  */
      53        else
      54  	return x;		/* x is integral  */
      55      }
      56    w = TWO23[sx] + x;
      57    return w - TWO23[sx];
      58  #endif /* ! USE_RINTF_BUILTIN  */
      59  }
      60  #ifndef __rintf
      61  libm_alias_float (__rint, rint)
      62  #endif