[PATCH] D105098: [DSE][NFC] Introduce "doesn't overwrite" return code for isOverwrite

Mon Sep 6 03:56:17 PDT 2021

fhahn added a comment.

Looks good in general, but I couldn't find a use in the linked patches. Could you update the description with more details about the motivation, when/how this will be used.

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Comment at: llvm/lib/Transforms/Scalar/DeadStoreElimination.cpp:1457
                               DepWriteOffset, InstWriteOffset);
         // If Current does not write to the same object as KillingDef, check
         // the next candidate.
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The comment here seems slightly inaccurate and I think it is more obvious after this change; we skip if we can't prove that there is a (partial) overwrite. Might be good to adjust the comment.

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Comment at: llvm/lib/Transforms/Scalar/DeadStoreElimination.cpp:1468
             WalkerStepLimit -= 1;
+            LLVM_DEBUG(dbgs() << "   ... reached partial limit ... continue with next access\n");
             continue;
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This seems unrelated to the patch?

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D105098/new/

https://reviews.llvm.org/D105098