[PATCH] D111768: [IPT] Restructure cache to allow lazy update following invalidation

[Max Kazantsev via Phabricator via llvm-commits]

mkazantsev added inline comments.


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Comment at: llvm/lib/Analysis/InstructionPrecedenceTracking.cpp:96
+    if (&I == It->second)
+      // No special instruction before cached result
       return;
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This loosens the validation. What if  `I` is not special? We used to check this and now we don't.


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Comment at: llvm/lib/Analysis/InstructionPrecedenceTracking.cpp:128
+      FirstSpecialInsts[BB] = &*std::next(Inst->getIterator());
+  }
 }
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This looks correct, but it's not entirely an NFC. We used to completely drop cache, assuming that after the removal we could insert smth in the beginning of this block and this will be fine. Now, if we insert a special instruction before this point, it will not be found. Could you please review the users of `removeInstruction` and confirm that we never use it as invalidation for insertion (which we shouldn't be doing, but not a fact that we don't).


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D111768/new/

https://reviews.llvm.org/D111768