[PATCH] D50377: [MustExecute] Rework LoopSafetyInfo to make it more optimistic about throws

[Philip Reames via Phabricator via llvm-commits]

reames requested changes to this revision.
reames added inline comments.
This revision now requires changes to proceed.


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Comment at: lib/Analysis/MustExecute.cpp:32
+  ICF.clear();
+  MayThrow = false;
+  // Figure out the fact that at least one block may throw.
----------------
We could chose to be more precise here by recomputing MayThrow lazily after invalidation.


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Comment at: lib/Transforms/Scalar/LICM.cpp:406
         Changed = true;
+        BlockChanged = true;
         continue;
----------------
Invalidation is needed eagerly here.


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Comment at: lib/Transforms/Scalar/LICM.cpp:474
           CurAST->deleteValue(&I);
           I.eraseFromParent();
         }
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BUG. Missing invalidation.


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Comment at: lib/Transforms/Scalar/LICM.cpp:1267
 
   Value *SomePtr = *PointerMustAliases.begin();
   BasicBlock *Preheader = CurLoop->getLoopPreheader();
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There needs to be some invalidations somewhere within this function.


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Comment at: lib/Transforms/Scalar/LoopUnswitch.cpp:514
   AC = &getAnalysis<AssumptionCacheTracker>().getAssumptionCache(
       *L->getHeader()->getParent());
   LI = &getAnalysis<LoopInfoWrapperPass>().getLoopInfo();
----------------
The fact there is no invalidation in loop unswitch is severely suspicious.


https://reviews.llvm.org/D50377