[PATCH] D22778: Add Loop Sink pass to reverse the LICM based of basic block frequency.
David Li via llvm-commits
llvm-commits at lists.llvm.org
Mon Oct 17 11:36:00 PDT 2016
davidxl added a comment.
M is the number of use BBs.
The pass already filters out loops which do not have any cold blocks -- this effectively filters out most of the loops in reality so the compile time impact will be minimal. Further more, the following can be done:
1. only collect cold bbs in the loop body that is colder than header and sort them instead
2. skip any instructions with use BBs that are not member of the cold BBs collected in 1).
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