Datapath

A datapath comprises the processor registers, functional units and connections through which instruction operands and results move. Control signals select operand sources, operations, memory access and processor register writeback. Connecting a barrel shifter before an arithmetic logic unit permits shift-and-add operations in one pass, but puts their delays in series.

A component executing a class of operations, such as addition or multiplication. Operand availability, unit occupancy and result-broadcast capacity can independently constrain its scheduling.