Support for Conditional Execution in Selective Scheduling
Abstract
Conditional execution is a hardware feature available in some CPUs that allows assigning instruction a predicate so that instruction will only execute if the predicate is true. In this paper we propose a method for supporting conditional execution in the instruction scheduler and discuss the advantages of this approach compared to a stand-alone optimization pass that precedes the instruction scheduling. We have implemented the proposed optimization in the selective scheduling in GCC compiler. Experimental results show an average improvement of 2% (and up to 16% on selected tests) for SPECFP part of SPEC CPU2000 benchmark.
About the Authors
Dmitry Melnik
ISP RAS, Moscow
Russian Federation
Russian Federation
Alexandr Monakov
ISP RAS, Moscow
Russian Federation
Russian Federation
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Review
For citations:
Melnik D., Monakov A. Support for Conditional Execution in Selective Scheduling. Proceedings of the Institute for System Programming of the RAS (Proceedings of ISP RAS). 2011;21. (In Russ.)
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