Explain about RISC architecture, Computer Engineering


Let's first list some significant considerations of RISC architecture:

1. RISC functions are kept simple unless there is a very good reason to do otherwise. A new operation which increases execution time of an instruction by 10 per cent can be added only if it decreases size of the code by at least 10 per cent. Even greater reductions might be necessary if the extra modification requires a change in design.

2. Micro-instructions stored in CU cannot be faster than simple instructions because the cache is built from same technology as writable control unit store, a simple instruction can be executed at same speed as that of a micro-instruction.

3. Microcode is not magic. Moving software into microcode doesn't make it better; it only makes it harder to change. Runtime library of RISC has all characteristics of functions in microcode, except that it's easier to change.

4. Simple decoding and pipelined execution are more significant than program size. Pipelined execution gives a peak performance of one instruction each step. The longest step determines the performance rate of pipelined machine so ideally every pipeline step must take same amount of time. 

5. Compiler must simplify instructions instead of generate complex instructions. RISC compilers try to eliminate as much work as possible at the time of compile time so that simple instructions can be used. For illustration RISC compilers attempt to keep operands in registers so that simple register-to-register instructions can be used. RISC compilers keep operands which will be reused in registers instead of repeating a memory access or a calculation. They consequently use LOADs and STOREs to access memory so that operands aren't implicitly discarded after being fetched.

Posted Date: 7/30/2013 5:33:18 AM | Location : United States

Related Discussions:- Explain about RISC architecture, Assignment Help, Ask Question on Explain about RISC architecture, Get Answer, Expert's Help, Explain about RISC architecture Discussions

Write discussion on Explain about RISC architecture
Your posts are moderated
Related Questions
Compare the basic COCOMO model with the detailed COCOMO model. COCOMO having of a hierarchy of three increasingly detailed and accurate forms. -  Basic COCOMO - is a stati

Q. Illustrate Left shift register with parallel load? A register that shifts data in one direction only is known as Uni-directional shift register and a register that can shift

Q. Speed Up - metrics for performance evaluation? Speed up is ratio of time needed to execute a given program employing a specific algorithm on a machine with single processor

Problem : a) What do you meant by a Multimedia Authoring System? b) Compare the verbose syntax to the dot syntax in Lingo. c) Explain each of the following terms: i) L

What are virtual Functions

The main aim of using LINQ to Dataset is to run strongly typed queries on Dataset. Assume we want to combine the results from two Datasets, or we need to take a distinct value f

Why cant datareader be returned from a Web Services Method? Ans) Because datareader is not serializable.

A set of techniques that allow executing a program which is not entirely in memory is called ? Ans. virtual memory which allows executing a program that is not entirely in me

Q. What is Cartridge Drive? Cartridge Drive: A cartridge is a protective covering or case which is used to hold a magnetic tape, disk, a printer ribbon or toner. Contents are

What are event and its types? An event is an occurrence at a point in time, like user depresses left button. Event happens instantaneously with regard to time scale. Type