Abstract
We introduce the concept of future values. Using future values it is possible to represent programs in a new control-flow form such that on any control flow path the data-flow aspect of the computation is either traditional (i.e., definition of a value precedes its consumers), or reversed (i.e., consumers of a value precede its definition). The representation hence allows unrestricted code motion since ordering of instructions are not prohibited by the data dependencies. We present a new program representation called Recursive Future Predicated Form (RFPF) which implements the concept. RFPF subsumes general if-conversion and permits unrestricted code motion to the extent that the whole procedure can be reduced to a single block. We develop algorithms which enable instruction movement in acyclic as well as cyclic regions and give examples of various optimizations in RFPF form.
Keywords
- Cyclic Code
- Program Representation
- Memory Operation
- Predicate Expression
- Programme Language Design
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
This work is supported in part by a NSF CAREER award (CCR-0347592) to Soner Önder.
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Ding, S., Önder, S. (2010). Unrestricted Code Motion: A Program Representation and Transformation Algorithms Based on Future Values . In: Gupta, R. (eds) Compiler Construction. CC 2010. Lecture Notes in Computer Science, vol 6011. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-11970-5_3
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DOI: https://doi.org/10.1007/978-3-642-11970-5_3
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