[PATCH] D72299: [DSE] Improve mayThrowBetween for 2 instructions in the same BB.

[Eli Friedman via Phabricator via llvm-commits]

efriedma added inline comments.


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Comment at: llvm/lib/Transforms/Scalar/DeadStoreElimination.cpp:1644
+    return BlockMap->second[SI] !=
+           BlockMap->second[&*std::prev(NI->getIterator())];
+  }
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What happens if NI is the first instruction in the block?  Or is that impossible in this context?


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Comment at: llvm/lib/Transforms/Scalar/DeadStoreElimination.cpp:1706
+  // between them.
+  DenseMap<BasicBlock *, DenseMap<Instruction *, unsigned>> ThrowingBlocks;
 
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This map seems sort of expensive, but maybe not a big deal relative to other stuff we have here already.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D72299/new/

https://reviews.llvm.org/D72299