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#include "bid_internal.h"

BID_TYPE0_FUNCTION_ARGTYPE1_NORND(int, bid32_ilogb, BID_UINT32, x)

  BID_UINT32 sign_x, coefficient_x;
  int_float dx;
  int exponent_x, bin_expon_cx, digits, res;


  // unpack arguments, check for NaN or Infinity
  if (!unpack_BID32 (&sign_x, &exponent_x, &coefficient_x, x)) {
    // x is Inf. or NaN
#ifdef BID_SET_STATUS_FLAGS
      __set_status_flags (pfpsf, BID_INVALID_EXCEPTION);
#endif
	  res = ((x & 0x7c000000) == 0x78000000) ? 0x7fffffff : 0x80000000;

      BID_RETURN (res);
  }
  // find number of digits in coefficient
  if (coefficient_x >= 1000000ull) {
    digits = 7;
  } else {
    dx.d = (float)coefficient_x;   // exact conversion;
    bin_expon_cx = (int)(dx.i >> 23) - 127;
    digits = bid_estimate_decimal_digits[bin_expon_cx];
    if (coefficient_x >= bid_power10_table_128[digits].w[0])
      digits++;
  }
  exponent_x = exponent_x - DECIMAL_EXPONENT_BIAS_32 + digits - 1;

  BID_RETURN (exponent_x);
}
