alignment.sol

pragma solidity ^0.8.0;

contract AlignmentChecker {
  function checkAlignment(uint256 x) public view returns (uint256) {
    assembly {
      let alignment := 32
      let num := x
      let mask := and(num, sub(alignment, 1))
      let isAligned := iszero(mask)
      if isAligned {
        // number is aligned
        return (0x00, 32)
      }
      let remainder := sub(alignment, mask)
      mstore(0x00, remainder)
      return (0x00, 32)
    }
  }
}