[PATCH] D68191: Simplify function llvm::removeUnreachableBlocks() to avoid (re-)computation.

[Florian Hahn via Phabricator via llvm-commits]

fhahn accepted this revision.
fhahn added a comment.
This revision is now accepted and ready to land.

Nice catch. This should be better overall, as instead of iterating over the whole function to delete dead blocks, we just iterate over the dead blocks. Even more work is skipped in case we have a DTU.

LGTM



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Comment at: llvm/lib/Transforms/Utils/Local.cpp:2231
     auto *BB = &*I;
-    if (Reachable.count(BB))
+    // skip reachable basic blocks
+    if (Reachable.find(BB) != Reachable.end())
----------------
In LLVM comments tend to be sentences, i.e. capitalize Skip and add a full stop.


================
Comment at: llvm/lib/Transforms/Utils/Local.cpp:2276
+  } else {
+    for (auto *BB : DeadBlockSet) {
+      BB->eraseFromParent();
----------------
I think most code in LLVM tends to omit unnecessary braces for single statement blocks.


Repository:
  rL LLVM

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https://reviews.llvm.org/D68191