1. Instruction sets

1.1 Instruction set evolution

An instruction set is the interface between hardware (processor) and software. It is the target of a compiler, which generates the binary code corresponding to the assembly instructions defined by the instruction set. An instruction set must be independent of the underlying hardware, so that it can run on different hardware architectures, with different levels of complexity and performance. This distinction has existed since the IBM360 (1965), and has led to a complete range of machines, from the smallest (360-20) to the most powerful (360-195), all having the same instruction set.

Article [H 1 999] presents the general characteristics of the different...