JIT: experimental changes to redundant branch opts #83859
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Recognize a particular case where a control flow pattern involving two BBJ_COND blocks with relops that test the same VNs can be simplified to a single relop in the dominating block. As part of this, teach VN about some of the rudiments of boolean simplification (DeMorgan's laws) and how to simplify some NOT / AND / OR expressions involving relops. Addresses some of the cases in dotnet#81220.
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Tagging subscribers to this area: @JulieLeeMSFT, @jakobbotsch, @kunalspathak Issue DetailsRecognize a particular case where a control flow pattern involving two BBJ_COND blocks with relops that test the same VNs can be simplified to a single relop in the dominating block. As part of this, teach VN about some of the rudiments of boolean simplification (DeMorgan's laws) and how to simplify some NOT / AND / OR expressions involving relops. Addresses some of the cases in #81220.
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@EgorBo FYI Needs some streamlining, eg the VN lookup tables are just searched by brute force... |
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Draft Pull Request was automatically closed for 30 days of inactivity. Please let us know if you'd like to reopen it. |
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Recognize a particular case where a control flow pattern involving two BBJ_COND blocks with relops that test the same VNs can be simplified to a single relop in the dominating block.
As part of this, teach VN about some of the rudiments of boolean simplification (DeMorgan's laws) and how to simplify some NOT / AND / OR expressions involving relops.
Addresses some of the cases in #81220.