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.
Some of the complicated processors use a pipeline of instruction registers where each stage of the pipeline does part of the decoding, preparation or execution and then passes it to the next stage for its step. Modern processors can even do some of the steps out of order as decoding on several instructions is done in parallel.
Decoding the op-code in the instruction register includes determining the instruction, determining where its operands are in memory, retrieving the operands from memory, allocating processor resources to execute the command (in super scalar processors), etc.
The output of the IR is available to control circuits, which generate the timing signals that control the various processing elements involved in executing the instruction.
In the instruction cycle, the instruction is loaded into the instruction register after the processor fetches it from the memory location pointed to by the program counter.
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Couvre les fondamentaux des processeurs, de la logique numérique à l'exécution de programme, y compris les composants comme ALU, fichier de registre, et la logique de contrôle.
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. Some of the complicated processors use a pipeline of instruction registers where each stage of the pipeline does part of the decoding, preparation or execution and then passes it to the next stage for its step.
L’architecture dite architecture de von Neumann est un modèle pour un ordinateur qui utilise une structure de stockage unique pour conserver à la fois les instructions et les données demandées ou produites par le calcul. De telles machines sont aussi connues sous le nom d’ordinateur à programme enregistré. La séparation entre le stockage et le processeur est implicite dans ce modèle. Cette architecture est appelée ainsi en référence au mathématicien John von Neumann, qui a élaboré en juin 1945 dans le cadre du projet EDVAC la première description d’un ordinateur dont le programme est stocké dans sa mémoire.
A central processing unit (CPU)—also called a central processor or main processor—is the most important processor in a given computer. Its electronic circuitry executes instructions of a computer program, such as arithmetic, logic, controlling, and input/output (I/O) operations. This role contrasts with that of external components, such as main memory and I/O circuitry, and specialized coprocessors such as graphics processing units (GPUs). The form, design, and implementation of CPUs have changed over time, but their fundamental operation remains almost unchanged.
Multiprocessors are a core component in all types of computing infrastructure, from phones to datacenters. This course will build on the prerequisites of processor design and concurrency to introduce