An instruction set is said to be orthogonal if it lacks redundancy (i.e., there is only a single instruction that can be used to accomplish a given task) and is designed such that instructions can use any register in any addressing mode. This terminology results from considering an instruction as a vector whose components are the instruction ...

The table below compares basic information about instruction set architectures. Notes: Usually the number of registers is a power of two, e.g. 8, 16, 32.In some cases a hardwired-to-zero pseudo-register is included, as "part" of register files of architectures, mostly to simplify indexing modes. The column "Registers" only counts the integer "registers" usable by general …

Single instruction, multiple data (SIMD) is a type of parallel processing in Flynn's taxonomy.SIMD can be internal (part of the hardware design) and it can be directly accessible through an instruction set architecture (ISA), but it should not be confused with an ISA. SIMD describes computers with multiple processing elements that perform the same operation on …

In computing, Streaming SIMD Extensions (SSE) is a single instruction, multiple data instruction set extension to the x86 architecture, designed by Intel and introduced in 1999 in their Pentium III series of Central processing units (CPUs) shortly after the appearance of Advanced Micro Devices (AMD's) 3DNow!.SSE contains 70 new instructions (65 unique mnemonics …

A CPU cache is a hardware cache used by the central processing unit (CPU) of a computer to reduce the average cost (time or energy) to access data from the main memory. A cache is a smaller, faster memory, located closer to a processor core, which stores copies of the data from frequently used main memory locations.Most CPUs have a hierarchy of multiple cache levels …

In statistics, the standard deviation is a measure of the amount of variation or dispersion of a set of values. A low standard deviation indicates that the values tend to be close to the mean (also called the expected value) of the set, while a high standard deviation indicates that the values are spread out over a wider range.. Standard deviation may be abbreviated SD, and is most …

The instruction cycle (also known as the fetch–decode–execute cycle, or simply the fetch-execute cycle) is the cycle that the central processing unit (CPU) follows from boot-up until the computer has shut down in order to process instructions. It is composed of three main stages: the fetch stage, the decode stage, and the execute stage.

In computer science, an instruction set architecture (ISA), also called computer architecture, is an abstract model of a computer.A device that executes instructions described by that ISA, such as a central processing unit (CPU), is called an implementation.. In general, an ISA defines the supported instructions, data types, registers, the hardware support for managing main memory, …

In computing, the instruction register (IR) or current instruction register (CIR) is the part of a CPU's control unit that holds the instruction currently being executed or decoded. In simple processors, each instruction to be executed is loaded into the instruction register, which holds it while it is decoded, prepared and ultimately executed, which can take several steps.

A central processing unit (CPU), also called a central processor, main processor or just processor, is the electronic circuitry that executes instructions comprising a computer program.The CPU performs basic arithmetic, logic, controlling, and input/output (I/O) operations specified by the instructions in the program. This contrasts with external components such as …