RISC vs CISC
What is RISC?
RISC is designed to perform a smaller number of types of computer instruction. Hence, it can operate at a higher speed. The full form of RISC is Reduced Instruction Set Computers. It is a microprocessor that is designed to perform smaller number of computer instruction so that it can operate at a higher speed. RISC instruction sets hold less than 100 instructions and use a fixed instruction format. This method uses a few simple addressing modes that use a register-based instruction. In this compiler development mechanism, LOAD/STORE is the only individual instructions for accessing memory.
RISC vs CISC – Key Differences
Here, are the important differences between CISC vs. RISC
Characteristics of CISC
Here, are important characteristics Of CISC One instruction is needed to support multiple addressing modes.
A large number of instructions. Instruction-decoding logic will be complex. Instructions for special tasks used infrequently. A large variety of addressing modes It offers variable-length instruction formats. Instruction are larger than one-word size. Instruction may take more than a single clock cycle to get executed. Less number of general-purpose registers as operation get performed in memory itself. Various CISC designs are set up with two special registers for the stack pointer for managing interrupts
Characteristics of RISC
Here, are an important characteristic of RICS:
Simpler instruction decoding A number of general-purpose registers. Simple Addressing Modes Fewer Data types. A pipeline can be achieved One instruction per cycle Register-to-register operations Simple instruction format Instruction execution would be faster Smaller Programs
CISC Advantages
Here, are pros/benefits of CISC
In CISC it is easy to add new commands into the chip without need to change the structure of the instruction set This architecture allows you to make efficient use of main memory The compiler should not be very complicated, as with the case of CISC. The instruction sets can be written to match the structures of high-level languages.
RISC Advantages
Here, are pros/benefits of RISC
Complex and efficient machine instructions. It offers extensive addressing capabilities for memory management. Relatively few registers when compared with RISC processors It helps you to reduce the instruction set. Offers limited addressing schemes for memory operands
CISC Disadvantages
Here, are Cons/ Drawbacks of CISC
Earlier generations of a processor family mostly contained as a subset in every new version. Hence, instruction set & chip hardware becomes complex with each generation of computers. The performance of the machine slows down because of clock time taken by different instructions will never be similar. They are larger as they require more transistors
RISC Disadvantages
Here, are Cons/Drawbacks of RISC
The performance of the RISC processors depends on the programmer or compiler. Compiler plays an important role while converting the CISC code to a RISC code RISC processors have large memory caches on the chip itself. RISC architecture necessitates on-chip hardware to be continuously reprogrammed.
