[PATCH] D157581: [SelectionDAG][X86][WIP] Don't always seperate conditions in `(br (and/or cond0, cond1))` into seperate branches
    Craig Topper via Phabricator via llvm-commits 
    llvm-commits at lists.llvm.org
       
    Wed Aug  9 21:13:57 PDT 2023
    
    
  
craig.topper added a comment.
I have wondered in the past if this should be done by codegenprepare instead of SelectionDAGBuilder. I believe codegenprepare does it for fast isel.
The current code in SelectionDAGBuilder doesn’t sink an AND so it blocks forming TEST instructions. CodegenPrepare already knows how to sink AND to be near compare.
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  rG LLVM Github Monorepo
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  https://reviews.llvm.org/D157581/new/
https://reviews.llvm.org/D157581
    
    
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