[PATCH] D64376: [MBP] Avoid tail duplication if it can't bring benefit

[Guozhi Wei via Phabricator via llvm-commits]

Carrot marked an inline comment as done.
Carrot added inline comments.


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Comment at: lib/CodeGen/MachineBlockPlacement.cpp:1069
 /// into all of its unplaced, unfiltered predecessors, that are not BB.
 bool MachineBlockPlacement::canTailDuplicateUnplacedPreds(
     const MachineBasicBlock *BB, MachineBasicBlock *Succ,
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davidxl wrote:
> Can the code be restructured here so that it  picks and returns  the top two most profittable predecessors and perform tail dup into them?
Current tail duplication can do it for 0 or all its predecessors. Duplicate a BB into hot predecessors only is in future plan.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D64376/new/

https://reviews.llvm.org/D64376