Summary
Having completed this chapter, you should have a good understanding of the top-level architectures and features of the x86, x64, 32-bit ARM, and 64-bit ARM registers, instruction sets, and assembly languages.
The x86 and x64 architectures represent a mostly CISC approach to processor design, with variable-length instructions that can take many cycles to execute, a lengthy pipeline, and (in x86) a limited number of processor registers.
The ARM architectures, on the other hand, are RISC processors with mostly single-cycle instruction execution, a large register set, and (somewhat) fixed-length instructions. Early versions of ARM had pipelines as short as three stages, though later versions have considerably more stages.
Is one of these architectures better than the other, in a general sense? It may be that each is better in some ways, and system designers must make their selection of processor architecture based on the specific needs of the system under development....
