BitMath

This library provides functionality for computing bit properties of an unsigned integer

Functions​

mostSignificantBit​

  function mostSignificantBit(
    uint256 x
  ) internal pure returns (uint8 r)

Returns the index of the most significant bit of the number, where the least significant bit is at index 0 and the most significant bit is at index 255

The function satisfies the property: x >= 2mostSignificantBit(x) and x < 2(mostSignificantBit(x)+1)

Parameters:​

Name	Type	Description
x	uint256	the value for which to compute the most significant bit, must be greater than 0

Return Values:​

Name	Type	Description
r	uint8	the index of the most significant bit

leastSignificantBit​

  function leastSignificantBit(
    uint256 x
  ) internal pure returns (uint8 r)

Returns the index of the least significant bit of the number, where the least significant bit is at index 0 and the most significant bit is at index 255

The function satisfies the property: (x & 2leastSignificantBit(x)) != 0 and (x & (2(leastSignificantBit(x)) - 1)) == 0)

Parameters:​

Name	Type	Description
x	uint256	the value for which to compute the least significant bit, must be greater than 0

Return Values:​

Name	Type	Description
r	uint8	the index of the least significant bit