Relation To Instruction Set Architecture
The ISA is roughly the same as the programming model of a processor as seen by an assembly language programmer or compiler writer. The ISA includes the execution model, processor registers, address and data formats among other things. The microarchitecture includes the constituent parts of the processor and how these interconnect and interoperate to implement the ISA.
The microarchitecture of a machine is usually represented as (more or less detailed) diagrams that describe the interconnections of the various microarchitectural elements of the machine, which may be everything from single gates and registers, to complete arithmetic logic units (ALUs) and even larger elements. These diagrams generally separate the datapath (where data is placed) and the control path (which can be said to steer the data).
Each microarchitectural element is in turn represented by a schematic describing the interconnections of logic gates used to implement it. Each logic gate is in turn represented by a circuit diagram describing the connections of the transistors used to implement it in some particular logic family. Machines with different microarchitectures may have the same instruction set architecture, and thus be capable of executing the same programs. New microarchitectures and/or circuitry solutions, along with advances in semiconductor manufacturing, are what allows newer generations of processors to achieve higher performance while using the same ISA.
In principle, a single microarchitecture could execute several different ISAs with only minor changes to the microcode.
Read more about this topic: Microarchitecture
Famous quotes containing the words relation to, relation, instruction, set and/or architecture:
“It would be disingenuous, however, not to point out that some things are considered as morally certain, that is, as having sufficient certainty for application to ordinary life, even though they may be uncertain in relation to the absolute power of God.”
—René Descartes (1596–1650)
“A theory of the middle class: that it is not to be determined by its financial situation but rather by its relation to government. That is, one could shade down from an actual ruling or governing class to a class hopelessly out of relation to government, thinking of gov’t as beyond its control, of itself as wholly controlled by gov’t. Somewhere in between and in gradations is the group that has the sense that gov’t exists for it, and shapes its consciousness accordingly.”
—Lionel Trilling (1905–1975)
“Everything from airplanes to kitchen blenders—and even chopsticks—comes with an instruction manual. Children, despite all their complexity, do not.”
—Lawrence Kutner (20th century)
“Is it enough
That the dish of milk is set out at night,
That we think of him sometimes,
Sometimes and always, with mixed feelings?”
—John Ashbery (b. 1927)
“In short, the building becomes a theatrical demonstration of its functional ideal. In this romanticism, High-Tech architecture is, of course, no different in spirit—if totally different in form—from all the romantic architecture of the past.”
—Dan Cruickshank (b. 1949)