In computer science, instruction selection is the stage of a compiler backend that transforms its tree-based middle-level intermediate representation (IR) into a low-level IR very close to its final target language. In a typical compiler, it precedes both instruction scheduling and register allocation, so its output IR has an infinite set of pseudoregisters and may still be subject to peephole optimization; otherwise, it closely resembles the target machine code, bytecode, or assembly language. It works by "covering" the intermediate representation with as few tiles as possible. A tile is a template that matches a portion of the IR tree and can be implemented with a single target instruction.
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Famous quotes containing the words instruction and/or selection:
“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.”
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