[DomTreeUpdater] Move critical edge splitting code to updater (#115111)

Support critical edge splitting in dominator tree updater. Continue the
work in #100856.

Compile time check:
https://llvm-compile-time-tracker.com/compare.php?from=87c35d782795b54911b3e3a91a5b738d4d870e55&to=42b3e5623a9ab4c3648564dc0926b36f3b438a3a&stat=instructions%3Au

1 files changed, 5 insertions, 1 deletions

diff --git a/llvm/lib/CodeGen/MachineSink.cpp b/llvm/lib/CodeGen/MachineSink.cpp
index 7d0bedab..bdf1ef6 100644
--- a/llvm/lib/CodeGen/MachineSink.cpp
+++ b/llvm/lib/CodeGen/MachineSink.cpp
@@ -30,6 +30,7 @@
 #include "llvm/CodeGen/MachineBlockFrequencyInfo.h"
 #include "llvm/CodeGen/MachineBranchProbabilityInfo.h"
 #include "llvm/CodeGen/MachineCycleAnalysis.h"
+#include "llvm/CodeGen/MachineDomTreeUpdater.h"
 #include "llvm/CodeGen/MachineDominators.h"
 #include "llvm/CodeGen/MachineFunction.h"
 #include "llvm/CodeGen/MachineFunctionPass.h"
@@ -747,8 +748,11 @@ bool MachineSinking::runOnMachineFunction(MachineFunction &MF) {
       MadeChange |= ProcessBlock(MBB);
 
     // If we have anything we marked as toSplit, split it now.
+    MachineDomTreeUpdater MDTU(DT, PDT,
+                               MachineDomTreeUpdater::UpdateStrategy::Lazy);
     for (const auto &Pair : ToSplit) {
-      auto NewSucc = Pair.first->SplitCriticalEdge(Pair.second, *this);
+      auto NewSucc =
+          Pair.first->SplitCriticalEdge(Pair.second, *this, nullptr, &MDTU);
       if (NewSucc != nullptr) {
         LLVM_DEBUG(dbgs() << " *** Splitting critical edge: "
                           << printMBBReference(*Pair.first) << " -- "