BitMath

Git Source

Helper contract used for bit calculations

Functions

closestBitRight

Returns the index of the closest bit on the right of x that is non null

function closestBitRight(uint256 x, uint8 bit) internal pure returns (uint256 id);

Parameters

Name	Type	Description
x	uint256	The value as a uint256
bit	uint8	The index of the bit to start searching at

Returns

Name	Type	Description
id	uint256	The index of the closest non null bit on the right of x. If there is no closest bit, it returns max(uint256)

closestBitLeft

Returns the index of the closest bit on the left of x that is non null

function closestBitLeft(uint256 x, uint8 bit) internal pure returns (uint256 id);

Parameters

Name	Type	Description
x	uint256	The value as a uint256
bit	uint8	The index of the bit to start searching at

Returns

Name	Type	Description
id	uint256	The index of the closest non null bit on the left of x. If there is no closest bit, it returns max(uint256)

mostSignificantBit

Returns the index of the most significant bit of x This function returns 0 if x is 0

function mostSignificantBit(uint256 x) internal pure returns (uint8 msb);

Parameters

Name	Type	Description
x	uint256	The value as a uint256

Returns

Name	Type	Description
msb	uint8	The index of the most significant bit of x

leastSignificantBit

Returns the index of the least significant bit of x This function returns 255 if x is 0

function leastSignificantBit(uint256 x) internal pure returns (uint8 lsb);

Parameters

Name	Type	Description
x	uint256	The value as a uint256

Returns

Name	Type	Description
lsb	uint8	The index of the least significant bit of x