Itanium® Architecture for Programmers: Understanding 64-Bit Processors and EPIC Principles

Summary

The concept of an architecture, apart from implementations, has progressively pervaded the computer industry since the introduction of the IBM 360 family. As the number of independent makers and truly different architectures has contracted over time, the lifespan of successful architectural families has tended to lengthen. Over periods of a decade or more, extensions to an architecture simply become inevitable, in order to accommodate different technology, different applications, or different markets.

This chapter has contrasted the first two implementations of the Itanium architecture, which differ primarily in their programmer-visible cache structures, pipeline depths, and instruction latencies. Very few Itanium instructions operate ...