[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 *>>;
+using MBBDomTreeGraphDiff = GraphDiff<MachineBasicBlock *, false>;
+
+extern template void Calculate<MBBDomTree>(MBBDomTree &DT);
+extern template void CalculateWithUpdates<MBBDomTree>(MBBDomTree &DT,
+                                                      MBBUpdates U);
+
+extern template void InsertEdge<MBBDomTree>(MBBDomTree &DT,
+                                            MachineBasicBlock *From,
+                                            MachineBasicBlock *To);
+
+extern template void DeleteEdge<MBBDomTree>(MBBDomTree &DT,
+                                            MachineBasicBlock *From,
+                                            MachineBasicBlock *To);
+
+extern template void ApplyUpdates<MBBDomTree>(MBBDomTree &DT,
+                                              MBBDomTreeGraphDiff &,
+                                              MBBDomTreeGraphDiff *);
+
+extern template bool Verify<MBBDomTree>(const MBBDomTree &DT,
+                                        MBBDomTree::VerificationLevel VL);
+} // namespace DomTreeBuilder
+
 //===-------------------------------------
 /// DominatorTree Class - Concrete subclass of DominatorTreeBase that is used to
 /// compute a normal dominator tree.
 ///
-class MachineDominatorTree : public MachineFunctionPass {
+class MachineDominatorTree : public MachineDomTree {
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arsenm wrote:

class + parent class naming is sort of confusing. I see MachineDomTree is just a typedef, so is there much point in keeping it? I think it would be clearer to make this directly : public DomTreeBase<MachineBasicBlock>

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