[PATCH] D82293: [CodeMoverUtils][WIP] Move code motion related checks from LICM to CodeMoverUtils

[Florian Hahn via Phabricator via llvm-commits]

fhahn added reviewers: reames, asbirlea, fhahn.
fhahn added inline comments.


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Comment at: llvm/include/llvm/Analysis/LoopAnalysisManager.h:63
   MemorySSA *MSSA;
+  PostDominatorTree &PDT;
+  DependenceInfo &DI;
----------------
Requiring those extra analysis here requires a strong motivation I think, as I think each loop pass has to make sure they are preserved or recomputed. 


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Comment at: llvm/lib/Transforms/Scalar/LICM.cpp:1392
+                                  DependenceInfo *DI) {
+  if (!isSafeToMoveBefore(I, Dest, *DT, *PDT, *DI))
+    return;
----------------
In order to make the transition to more general utils easier I think it might be worth considering making PDT/DI optional in the various utils and separate it from making DI & PDT required for all users, which potentially has quite a big impact. 

Also, I think LICM already uses MemorySSA to figure out if it is legal to move memory access out of the loop.


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D82293/new/

https://reviews.llvm.org/D82293