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#include "bid_internal.h"

BID128_FUNCTION_ARG1_NORND (bid128_logb, x)

  int ires, exponent_x;
  BID_UINT64  sign_x;
  BID_UINT128 res, CX;

  BID_SWAP128 (x);
  if (!unpack_BID128_value (&sign_x, &exponent_x, &CX, x)) {
    // test if x is NaN/Inf
  BID_SWAP128 (x);
if ((x.w[BID_HIGH_128W] & 0x7800000000000000ull) == 0x7800000000000000ull) {
#ifdef BID_SET_STATUS_FLAGS
  if ((x.w[BID_HIGH_128W] & 0x7e00000000000000ull) == 0x7e00000000000000ull)	// sNaN
    __set_status_flags (pfpsf, BID_INVALID_EXCEPTION);
#endif
	res.w[BID_HIGH_128W] = (CX.w[1]) & QUIET_MASK64;
	res.w[BID_LOW_128W] = CX.w[0];
	if ((x.w[BID_HIGH_128W] & 0x7c00000000000000ull) == 0x7800000000000000ull)
		res.w[BID_HIGH_128W] &= 0x7fffffffffffffffull;
	BID_RETURN (res);
  }

  // x is 0
#ifdef BID_SET_STATUS_FLAGS
    __set_status_flags (pfpsf, BID_ZERO_DIVIDE_EXCEPTION);
#endif
	res.w[BID_HIGH_128W] = 0xf800000000000000ull;
	res.w[BID_LOW_128W] = 0;
	BID_RETURN (res);

}

  BID_SWAP128 (x);
  BIDECIMAL_CALL1_NORND (bid128_ilogb, ires, x);
  if (ires & 0x80000000) {
    res.w[BID_HIGH_128W] = 0xb040000000000000ull;
    res.w[BID_LOW_128W] = (BID_UINT64)(-ires);
  } else {
    res.w[BID_HIGH_128W] = 0x3040000000000000ull;
    res.w[BID_LOW_128W] = (BID_UINT64)ires;
  }
  BID_RETURN (res);
}
