[MemorySSA] Update for partial unswitch.

Update MSSA for blocks cloned when doing partial unswitching.
Enable additional testing with MSSA.
Resolves PR43641.

llvm-svn: 374850

1 files changed, 7 insertions, 0 deletions

diff --git a/llvm/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp b/llvm/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp
index 4e7abfc5bda..fa9dbe240ba 100644
--- a/llvm/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp
+++ b/llvm/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp
@@ -2140,6 +2140,13 @@ static void unswitchNontrivialInvariants(
     // the branch in the split block.
     buildPartialUnswitchConditionalBranch(*SplitBB, Invariants, Direction,
                                           *ClonedPH, *LoopPH);
+    if (MSSAU) {
+      // Perform MSSA cloning updates.
+      for (auto &VMap : VMaps)
+        MSSAU->updateForClonedLoop(LBRPO, ExitBlocks, *VMap,
+                                   /*IgnoreIncomingWithNoClones=*/true);
+      MSSAU->updateExitBlocksForClonedLoop(ExitBlocks, VMaps, DT);
+    }
     DTUpdates.push_back({DominatorTree::Insert, SplitBB, ClonedPH});
   }