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Version: V3

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:

NameTypeDescription
xuint256the value for which to compute the most significant bit, must be greater than 0

Return Values:

NameTypeDescription
runit8the 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:

NameTypeDescription
xuint256the value for which to compute the least significant bit, must be greater than 0

Return Values:

NameTypeDescription
runit8the index of the least significant bit