examine, in general, the microarchitecture that exists at the control level of modern
computers.
All computers have a central processing unit. This unit can be divided into
two pieces. The first is the datapath, which is a network of storage units (registers)
and arithmetic and logic units (for performing various operations on data)
connected by buses (capable of moving data from place to place) where the timing
is controlled by clocks. The second CPU component is the control unit, a
module responsible for sequencing operations and making sure the correct data is
where it needs to be at the correct time. Together, these components perform the
tasks of the CPU: fetching instructions, decoding them, and finally performing
the indicated sequence of operations. The performance of a machine is directly
affected by the design of the datapath and the control unit. Therefore, we cover
these components of the CPU in detail in the following sections.