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/*******************************************************************************

*                                                                              *

*      File frexpldexp.c,                                                      *

*      Functions frexp(x) and ldexp(x),                                        *

*      Implementation of frexp and ldexp functions for the PowerPC.            *

*                                                                              *

*      Copyright © 1991 Apple Computer, Inc.  All rights reserved.             *

*                                                                              *

*      Written by Ali Sazegari, started on January 1991,                       *

*                                                                              *

*      W A R N I N G:  This routine expects a 64 bit double model.             *

*                                                                              *

*      December03 1992: first rs6000 implementation.                           *

*      October 05 1993: added special cases for NaN and ° in frexp.            *

*      May     27 1997: improved the performance of frexp by eliminating the   *

*                       switch statement.                                      *

*        June      13 2001: (ram) rewrote frexp to eliminate calls to scalb and    *

*                               logb.                                                                    *

*                                                                              *

*******************************************************************************/

#include <limits.h>

#include <math.h>

typedef union

      {

      struct {

#if defined(__BIG_ENDIAN__)

        unsigned long int hi;

        unsigned long int lo;

#else

        unsigned long int lo;

        unsigned long int hi;

#endif

      } words;

      double dbl;

      } DblInHex;

double ldexp ( double value, int exp )

      {

      if ( exp > SHRT_MAX )

            exp = SHRT_MAX;

      else if ( exp < -SHRT_MAX )

            exp = -SHRT_MAX;

      return scalb ( value, exp  );

      }