Explain about RISC architecture, Computer Engineering

Q. Explain about RISC ARCHITECTURE?

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
Q. What do you mean by Resolution? Resolution is parameter which defines possible sharpness or clarity of a video image.  Resolution is defined as number of pixels which make u

what are the output deice

What are the methods for handling deadlocks?  The deadlock problem can be dealt with in one of the three ways:  a. Use a protocol to prevent or avoid deadlocks, make sure th

Find out how many words can be formed out of the letters of the word DAUGHTER such that (i)  The vowels are all time together. (ii)  The vowels occupy even places.   Ans:

What is a serial port?  A serial port transfers and receives data single bit at a time.

Syntax errors and logical errors: Syntax errors also called as compilation errors are caused by violation of the grammar rules of the language. The compiler detects, isolate th

There are three primary colours in pigments - Red, Yellow and Blue. There are two ways to produce more colours:   Physical Mixing: Physically mix colours to produce a new colour

Ending transactions: Either side may request that a burst end after the present data phase. Simple PCI component that do not support multi-word bursts will always request this

Q. How to make frames for web documents? Intelligent use of frames can give your pages a cleaner look and make easier to navigate. The fundamental concept goes like this: Every

Can the size of an array be declared at runtime?              No, the size of an array can't be declared at run time, we always require to mention the dimensions of an array at