text: /* @(#)s_floor.c 5.1 93/09/24 */
  /*
   * ====================================================
   * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
   *
   * Developed at SunPro, a Sun Microsystems, Inc. business.
   * Permission to use, copy, modify, and distribute this
   * software is freely granted, provided that this notice
   * is preserved.
   * ====================================================
   */
  
  /*
   * truncf(x)
   * Return x rounded toward 0 to integral value
   * Method:
   *	Bit twiddling.
   * Exception:
   *	Inexact flag raised if x not equal to truncf(x).
   */
  
  #include "math.h"
  #include "math_private.h"
  
  static const float huge = 1.0e30F;
  
  float
  truncf(float x)
  {
  	int32_t i0,j0;
  	u_int32_t i;
  	GET_FLOAT_WORD(i0,x);
  	j0 = ((i0>>23)&0xff)-0x7f;
  	if(j0<23) {
  	    if(j0<0) { 	/* raise inexact if x != 0 */
  		if(huge+x>0.0F)		/* |x|<1, so return 0*sign(x) */
  		    i0 &= 0x80000000;
  	    } else {
  		i = (0x007fffff)>>j0;
  		if((i0&i)==0) return x; /* x is integral */
  		if(huge+x>0.0F)		/* raise inexact flag */
  		    i0 &= (~i);
  	    }
  	} else {
  	    if(j0==0x80) return x+x;	/* inf or NaN */
  	    else return x;		/* x is integral */
  	}
  	SET_FLOAT_WORD(x,i0);
  	return x;
  }
  