1. CISC vs RISC by : Kaushik Patra ([email protected]) a
beginners reference
2. Agenda A quick introduction Instruction Set Architecture
(ISA) ISA classification CISC philosophy RISC philosophy
Conclusion
3. Introduction
4. ISA Instruction Set Architecture. An agreement between
hardware and human for making interaction. Example : ADD R1, R2, R3
Can be represented as : 00101111100001111001010101010101
10111010100011110101001011011010
5. ISA Classification Two major schools of ISA CISC Complex
Instruction Set Computer RISC Reduced Instruction Set Computer
6. CISC Philosophy Reduce amount of storage used and accessed -
reduce load/store. Give support for compatibility. Make compilers
job easier. Support complex assembly level programming.
7. RISC Philosophy Execute one instruction per clock. Keep all
instructions of same size. Allow only load / store instruction to
access the memory. Give support for high level languages (like C,
C++, Java).
8. Conclusion CISC -> RISC : A paradigm shift Assembly ->
C / C++ / JAVA Much more design simplicity with RISC. Ensures
better pipelining. Memory is cheaper nowadays So, go for RISC style
design.