[CodeGen] Remove `applySplitCriticalEdges` in `MachineDominatorTree` (#97055)

Summary:
- Remove wrappers in `MachineDominatorTree`.
- Remove `MachineDominatorTree` update code in
`MachineBasicBlock::SplitCriticalEdge`.
- Use `MachineDomTreeUpdater` in passes which call
`MachineBasicBlock::SplitCriticalEdge` and preserve
`MachineDominatorTreeWrapperPass` or CFG analyses.

Commit abea99f65a97248974c02a5544eaf25fc4240056 introduced related
methods in 2014. Now we have SemiNCA based dominator tree in 2017 and
dominator tree updater, the solution adopted here seems a bit outdated.

1 files changed, 1 insertions, 1 deletions

diff --git a/llvm/lib/CodeGen/LiveDebugValues/InstrRefBasedImpl.cpp b/llvm/lib/CodeGen/LiveDebugValues/InstrRefBasedImpl.cpp
index 555cbb7..98099ac 100644
--- a/llvm/lib/CodeGen/LiveDebugValues/InstrRefBasedImpl.cpp
+++ b/llvm/lib/CodeGen/LiveDebugValues/InstrRefBasedImpl.cpp
@@ -2754,7 +2754,7 @@ void InstrRefBasedLDV::BlockPHIPlacement(
   // Apply IDF calculator to the designated set of location defs, storing
   // required PHIs into PHIBlocks. Uses the dominator tree stored in the
   // InstrRefBasedLDV object.
-  IDFCalculatorBase<MachineBasicBlock, false> IDF(DomTree->getBase());
+  IDFCalculatorBase<MachineBasicBlock, false> IDF(*DomTree);
 
   IDF.setLiveInBlocks(AllBlocks);
   IDF.setDefiningBlocks(DefBlocks);