[llvm] [CodeGen][NewPM] Split `MachineDominatorTree` into a concrete analysis result (PR #94571)

[Matt Arsenault via llvm-commits]

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@@ -44,11 +44,37 @@ extern template class DominatorTreeBase<MachineBasicBlock, true>; // PostDomTree
 using MachineDomTree = DomTreeBase<MachineBasicBlock>;
 using MachineDomTreeNode = DomTreeNodeBase<MachineBasicBlock>;
 
+namespace DomTreeBuilder {
+using MBBDomTree = MachineDomTree;
+using MBBUpdates = ArrayRef<llvm::cfg::Update<MachineBasicBlock *>>;
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arsenm wrote:

Don't need llvm::?

https://github.com/llvm/llvm-project/pull/94571