Instruerionsadresse

Instruerionsadresse is a term used in several Scandinavian language contexts to denote the memory address of a single instruction within a program’s code. The word is formed from instruere, meaning to instruct, and adresse, meaning address, and is roughly equivalent to the English “instruction address.” In practice, it identifies the memory location from which the processor will fetch the next instruction.

In most processors, the instruction address is tracked by a special register known as the program counter (PC) or instruction pointer (IP). The PC holds the address of the next instruction to fetch; after a fetch–execute cycle, the PC is updated to point to the following instruction, either by simple incrementation for fixed-size instructions or by computing a target for jumps and branches.

Instruction addresses are distinct from data addresses, which refer to memory locations containing data operands. Some computer architectures separate the two memory spaces, as in Harvard architectures, where instruction memory is separate from data memory. In Von Neumann architectures, there is a single address space for both instructions and data, making instruction addresses and data addresses interrelated.

Addressing modes define how an instruction’s address is determined. PC-relative addressing uses the current program counter plus an offset, while absolute addressing uses a fixed address. Relocation and linking can alter instruction addresses when code is loaded into memory, and position-independent code uses relative addressing to remain valid regardless of load location.

In debugging, disassembly, and performance analysis, instruction addresses are fundamental references. They help identify where in code execution occurs, locate branches or faults, and support the analysis of instruction fetch patterns, pipeline behavior, and cache interactions.