C Interfaces and Implementations: Techniques for Creating Reusable Software

Chapter 19. Multiple-Precision Arithmetic

The last of the three arithmetic interfaces, MP, exports functions that implement multiple-precision arithmetic on unsigned and two’s-complement integers. Like XP, MP reveals its representation for n-bit integers, and the MP functions operate on integers of a given size. Unlike XP, the lengths of MP’s integers are given in bits, and MP’s functions implement both signed and unsigned arithmetic. Like the AP functions, the MP functions enforce the usual suite of checked runtime errors.

MP is intended for applications that need extended-precision arithmetic, but want finer control over allocations, need both unsigned and signed operations, or must mimic two’s-complement n-bit arithmetic. Examples include compilers ...