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#include "bid_internal.h"

double exp(double);

BID_TYPE0_FUNCTION_ARGTYPE1(BID_UINT32, bid32_exp, BID_UINT32, x)

  BID_UINT32 res;
  double xd, rd;
  int z;

    // test if x is NaN
    if ((x & NAN_MASK32) == NAN_MASK32) {
#ifdef BID_SET_STATUS_FLAGS
      if (((x & SNAN_MASK32) == SNAN_MASK32)    // sNaN
          )
        __set_status_flags (pfpsf, BID_INVALID_EXCEPTION);
#endif
                res = x & 0xfc0fffff; //quiet and make combination 0 (canonize)
                if ((res & 0x000fffff) > 999999) { // payload
                        res &= ~0x000fffff;
                }
      BID_RETURN (res);
    }

        BIDECIMAL_CALL1_NORND_NOSTAT (bid32_isZero, z, x);
        if (z) {
                // 1 according C99
                res = 0x32800001;
           BID_RETURN (res);
        }
        BIDECIMAL_CALL1_NORND_NOSTAT (bid32_isInf, z, x);
        if (z) {
                // 0 or Inf according C99
                if (x & MASK_SIGN32) {
                        res = 0x32800000;
                } else {
                        res = 0x78000000;
                }
#ifdef BID_SET_STATUS_FLAGS
                *pfpsf = 0;
#endif
           BID_RETURN (res);
        }


// Otherwise just do the operation "naively".
// We inherit the special cases from the binary function,
// but deal with overflowing finite inputs carefully so
// things work in directed rounding modes.

  BIDECIMAL_CALL1(bid32_to_binary64,xd,x);

  if (xd > 700.0) rd = 1.0e200;
  else if (xd < -700.0) rd = 1.0e-200;
  else  rd = exp(xd);

  BIDECIMAL_CALL1(binary64_to_bid32,res,rd);

  BID_RETURN (res);

}
