[PATCH] D114586: [VPlan] Verify plan entry and exit blocks, set correct exit block.

[Ayal Zaks via Phabricator via llvm-commits]

Ayal added inline comments.


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Comment at: llvm/lib/Transforms/Vectorize/LoopVectorize.cpp:9562
          "entry block must be set to a VPRegionBlock having a non-empty entry "
          "VPBasicBlock");
   RecipeBuilder.fixHeaderPhis();
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Wonder if the above assert should also be taken care of by VPlan verify instead?


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Comment at: llvm/lib/Transforms/Vectorize/LoopVectorize.cpp:9633
 
+  cast<VPRegionBlock>(Plan->getEntry())->setExit(VPBB);
   // Now that sink-after is done, move induction recipes for optimized truncates
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Another way of fixing this would be to have split-blocks update Exit, when it updates VPBB?


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Comment at: llvm/lib/Transforms/Vectorize/VPlanVerifier.cpp:169
+    return false;
+  }
+  const VPBasicBlock *Exit = dyn_cast<VPBasicBlock>(TopRegion->getExit());
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The Entry and Exit blocks of any region in Plan must have no predecessors and successors, respectively, by definition; not only the top-most region, e.g., including internal replicating regions. Worth extending to check all regions in Plan? Entry and Exit blocks may themselves be regions, in general, so asserting that they be basic blocks should be restricted to the top-most region.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D114586/new/

https://reviews.llvm.org/D114586