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:
“The adolescent does not develop her identity and individuality by moving outside her family. She is not triggered by some magic unconscious dynamic whereby she rejects her family in favour of her peers or of a larger society.... She continues to develop in relation to her parents. Her mother continues to have more influence over her than either her father or her friends.”
—Terri Apter (20th century)
“There is a constant in the average American imagination and taste, for which the past must be preserved and celebrated in full-scale authentic copy; a philosophy of immortality as duplication. It dominates the relation with the self, with the past, not infrequently with the present, always with History and, even, with the European tradition.”
—Umberto Eco (b. 1932)
“I have come to believe ... that the stage may do more than teach, that much of our current moral instruction will not endure the test of being cast into a lifelike mold, and when presented in dramatic form will reveal itself as platitudinous and effete. That which may have sounded like righteous teaching when it was remote and wordy will be challenged afresh when it is obliged to simulate life itself.”
—Jane Addams (1860–1935)
“This is the Scroll of Thoth. Herein are set down the magic words by which Isis raised Osiris from the dead. Oh! Amon-Ra—Oh! God of Gods—Death is but the doorway to new life—We live today-we shall live again—In many forms shall we return-Oh, mighty one.”
—John L. Balderston (1899–1954)
“No architecture is so haughty as that which is simple.”
—John Ruskin (1819–1900)