Efficient modulo calculation

A non-transitory computer readable storage medium having stored thereon computer readable instructions that, when processed at a computer system for generating a manifestation of an integrated circuit, cause the computer system to generate a manifestation of an integrated circuit arranged to perform modulo calculation, the integrated circuit comprising a unit arranged to:

• receive an input n-bit value;
• generate at least one string from one or more bits of the value and a corresponding coefficient, wherein the corresponding coefficient comprises a selected one of 2i mod b and (2i mod b)−b having a smaller absolute magnitude and where i is a bit index of a least significant input bit in the string;
• add together the at least one string and one or more further strings to generate an output value;
• and
• output the output value.

A method of manufacturing, using an integrated circuit manufacturing system, an integrated circuit comprising hardware logic arranged to perform modulo calculation with respect to a constant value b, the hardware logic comprising a unit arranged to

• receive an input n-bit value;
• generate at least one string from one or more bits of the value and a corresponding coefficient, wherein the corresponding coefficient comprises a selected one of 2i mod b and (2i mod b)−b having a smaller absolute magnitude and where i is a bit index of a least significant input bit in the string;
• add together the at least one string and one or more further strings to generate an output value;
• and
• output the output value.