Computing Research Software

RISC vs. CISC and Programming

CISC architecture is known as ‘complex instruction set computer’, this architecture is based on the argument that a CPU is able to perform large numbers of complex instructions and therefore should be used to do so, even if they are redundant (Brookshear, 2009, p.85). RISC architecture is known as ‘reduced instruction set computer’, this architecture is based on the argument that the CPU should have a minimal set of instructions due to the fact that once a CPU has a certain minimum amount of instructions, adding any more does not increase capabilities and will only decrease the speed and efficiency of the machine (Brookshear, 2009, p.85).

The strengths of RISC over CISC are very apparent when reading though the paper by George (1990). In his paper he states that while CISC is more popular and will no doubt remain so in the near future due to backward-compatibility for current software, RISC has far more advantages when going forward due to the “constantly changing body of knowledge used for processor design”.

From my readings I believe that CISC processing is best suited for RAD (Rapid Application Development). In this day and age, at the pace of the IT and software industry it will help us with concentrating more on breaking new boundaries in development of less-complex software and design by taking the tedious work of programming operations that are run-of-the-mill requirements for every day applications away and allowing us to concentrate on more complex and new developments. Issues that may hamper this, however, is due to the fact that CISC processors are less efficient and take longer to process than RISC, and speed of execution is one of the most important factors in software today.

RISC processors allow us to have almost a “clean slate” when programming. With its minimal instruction set it can cater for new methods of developing the simplest of operations at a higher speed of what has been discovered and pre-programmed into the CPU like in CISC processors. RISC will also allow for more complex and low-level (more than likely larger, more advanced systems) development at more efficient performance due to the lack of excessive and potentially un-used instruction sets slowing down performance.

As far as future replacements, the popularity of the CISC chip may be replaced by the RISC chip as stated in the paper by George (2009). I do tend to agree on this but also by perhaps adding the ability for custom instructions to be stored in the CPU which would allow user/operating system/software defined instructions to be added dynamically for optimisation of that particular system configuration


Brookshear, J.G (2009) Computer Science: An Overview. 10th ed. China: Pearson Education Asia Ltd.

George, A.D (1990) “An overview of RISC vs. CISC”, System Theory, 1990. Twenty-second Southeastern Symposium on, 11-13 March, Cookeville. IEEE, pp.436-438.