EN FR
EN FR


Section: New Results

Dynamic Code Generation for Speculative Polyhedral Optimization

Participants : Juan Manuel Martinez Caamano, Philippe Clauss.

We have developped a new runtime code generation technique for speculative loop optimization and parallelization, that allows to generate on-the-fly codes resulting from any polyhedral optimizing transformation of loop nests, such as tiling, skewing, loop fission, loop fusion or loop interchange, without introducing a penalizing time overhead. The proposed strategy is based on the generation of code bones at compile-time, which are parametrized code snippets either dedicated to speculation management or to computations of the original target program. These code bones are then instantiated and assembled at runtime to constitute the speculatively-optimized code, as soon as an optimizing polyhedral transformation has been determined. Their granularity threshold is sufficient to apply any polyhedral transformation, while still enabling fast runtime code generation. This strategy has been implemented in the speculative loop parallelizing framework Apollo.