4.9. Addressing in Other Architectures
The Itanium EPIC architecture implements roughly the same number of addressing modes as RISC architectures. CISC architectures, however, offer a greater variety of addressing modes, some of which we will briefly describe.
4.9.1. Modes Built on Register Indirect Addressing
The VAX, as quintessential CISC architecture, provides an opportunity for contrast because it includes three variants of register indirect addressing:
| Register Indirect | (Rx) | Effective address = contents of Rx |
| Autoincrement | (Rx)+ | Effective address = contents of Rx |
| Rx is then advanced to the next information unit | ||
| Autodecrement | -(Rx) | Rx is moved back to the previous information unit |
| Then effective address = contents of Rx |
The computer adjusts the ...
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