[PATCH] D66911: [LoopUnroll] Use Lazy strategy for DTU used for MergeBlockIntoPredecessor.

[Florian Hahn via Phabricator via llvm-commits]

fhahn updated this revision to Diff 217752.
fhahn added a comment.

Add comment that DTU.getDomTree applies the updates to the DomTree.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D66911/new/

https://reviews.llvm.org/D66911

Files:
  llvm/lib/Transforms/Utils/LoopUnroll.cpp


Index: llvm/lib/Transforms/Utils/LoopUnroll.cpp
===================================================================
--- llvm/lib/Transforms/Utils/LoopUnroll.cpp
+++ llvm/lib/Transforms/Utils/LoopUnroll.cpp
@@ -870,7 +870,7 @@
   assert(!DT || !UnrollVerifyDomtree ||
          DT->verify(DominatorTree::VerificationLevel::Fast));
 
-  DomTreeUpdater DTU(DT, DomTreeUpdater::UpdateStrategy::Eager);
+  DomTreeUpdater DTU(DT, DomTreeUpdater::UpdateStrategy::Lazy);
   // Merge adjacent basic blocks, if possible.
   for (BasicBlock *Latch : Latches) {
     BranchInst *Term = dyn_cast<BranchInst>(Latch->getTerminator());
@@ -890,6 +890,8 @@
       }
     }
   }
+  // Apply updates to the DomTree.
+  DT = &DTU.getDomTree();
 
   // At this point, the code is well formed.  We now simplify the unrolled loop,
   // doing constant propagation and dead code elimination as we go.


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D66911.217752.patch
Type: text/x-patch
Size: 877 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20190829/30d349e9/attachment.bin>