[PATCH] D133321: [Assignment Tracking][24/*] Always RemoveRedundantDbgInstrs in instcombine in assignment tracking builds

[Orlando Cazalet-Hyams via Phabricator via llvm-commits]

Orlando added inline comments.


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Comment at: llvm/lib/Transforms/InstCombine/InstructionCombining.cpp:4353
     MadeIRChange = LowerDbgDeclare(F);
+  // LowerDbgDeclare calls RemoveRedundantDbgInstrs, but LowerDbgDeclare will
+  // almost never return true when running an assignment tracking build. Take
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chrisjackson wrote:
> Possible suitable branch hint location, based on your comment?
> 
> I'm not sure they are in the llvm's c++ version though.
This path is only hit once per instcombine run - IMHO it's not hot enough to worry about that. FWIW The hot areas in this patch stack are all around `DebugVariable` hashing and comparison in `DenseMap` and increased work/calls in/of RemoveRedundantDbgInstrs (we still do need this patch until deeper performance work takes place IMO).


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D133321/new/

https://reviews.llvm.org/D133321