Search results
Results from the WOW.Com Content Network
In computer science, an instruction set architecture (ISA) is an abstract model that generally defines how software controls the CPU in a computer or a family of computers. [1] A device or program that executes instructions described by that ISA, such as a central processing unit (CPU), is called an implementation of that ISA.
Every processor or processor family has its own instruction set. Instructions are patterns of bits, digits, or characters that correspond to machine commands. Thus, the instruction set is specific to a class of processors using (mostly) the same architecture. Successor or derivative processor designs often include instructions of a predecessor ...
The XSAVE instruction set extensions are designed to save/restore CPU extended state (typically for the purpose of context switching) in a manner that can be extended to cover new instruction set extensions without the OS context-switching code needing to understand the specifics of the new extensions.
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. [1] In simple processors, each instruction to be executed is loaded into the instruction register, which holds it while it is decoded, prepared and ultimately ...
An instruction set architecture (ISA) is an abstract model of a computer, also referred to as computer architecture.A realization of an ISA is called an implementation.An ISA permits multiple implementations that may vary in performance, physical size, and monetary cost (among other things); because the ISA serves as the interface between software and hardware.
The control unit (CU) is a component of a computer's central processing unit (CPU) that directs the operation of the processor. A CU typically uses a binary decoder to convert coded instructions into timing and control signals that direct the operation of the other units (memory, arithmetic logic unit and input and output devices, etc.).
For example, even though the IBM System/360 instruction set architecture was a 32-bit instruction set, the System/360 Model 30 and Model 40 had 8-bit data paths in the arithmetic logical unit, so that a 32-bit add required four cycles, one for each 8 bits of the operands, and, even though the Motorola 68000 series instruction set was a 32-bit ...
A complex instruction set computer (CISC / ˈ s ɪ s k /) is a computer architecture in which single instructions can execute several low-level operations (such as a load from memory, an arithmetic operation, and a memory store) or are capable of multi-step operations or addressing modes within single instructions.