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

Summary

A stack provides temporary storage that supplements the general purpose registers, and its operation as a dynamic data structure assists in the implementation of algorithms that benefit from reversing the order of items. In many traditional architectures, the stack pointer participates directly during subroutine call and return instructions to help preserve a return address and other context information.

In the Itanium architecture, calls and returns per se do not alter the stack pointer; rather, they are implemented as forms of the branch instruction. Moreover, the Itanium architecture implements a register stack engine whose autonomous operation provides a second stack mechanism for the programmer. The most convenient way to preserve ...