Editing Microarchitecture (section)

== Aspects ==
[[File:Intel i80286 arch.svg|thumb|upright=2|[[Intel 80286]] microarchitecture]]

The [[instruction pipeline|pipelined]] [[datapath]] is the most commonly used datapath design in microarchitecture today. This technique is used in most modern microprocessors, [[microcontroller]]s, and [[Digital signal processor|DSPs]]. The pipelined architecture allows multiple instructions to overlap in execution, much like an assembly line. The pipeline includes several different stages which are fundamental in microarchitecture designs.<ref name="hennessy" /> Some of these stages include instruction fetch, instruction decode, execute, and write back. Some architectures include other stages such as memory access. The design of pipelines is one of the central microarchitectural tasks.

Execution units are also essential to microarchitecture. Execution units include [[arithmetic logic unit]]s (ALU), [[floating point unit]]s (FPU), load/store units, branch prediction, and [[Single instruction, multiple data|SIMD]]. These units perform the operations or calculations of the processor. The choice of the number of execution units, their latency and throughput is a central microarchitectural design task. The size, latency, throughput and connectivity of memories within the system are also microarchitectural decisions.

System-level design decisions such as whether or not to include [[peripheral]]s, such as [[memory controller]]s, can be considered part of the microarchitectural design process. This includes decisions on the performance-level and connectivity of these peripherals.

Unlike architectural design, where achieving a specific performance level is the main goal, microarchitectural design pays closer attention to other constraints. Since microarchitecture design decisions directly affect what goes into a system, attention must be paid to issues such as chip area/cost, power consumption, logic complexity, ease of connectivity, manufacturability, ease of debugging, and testability.