[llvm] [Support][NFC] Use DomTreeBase methods in SemiNCA (PR #101059)

[Nikita Popov via llvm-commits]

================
@@ -586,7 +586,8 @@ struct SemiNCAInfo {
     // Loop over all of the discovered blocks in the function...
     for (NodePtr W : llvm::drop_begin(NumToNode)) {
       // Don't replace this with 'count', the insertion side effect is important
-      if (DT.DomTreeNodes[W]) continue;  // Haven't calculated this node yet?
+      if (DT.getNode(W))
----------------
nikic wrote:

The comment directly above this line claims that the insertion side effect is important. Either the new code or the old comment is wrong...

https://github.com/llvm/llvm-project/pull/101059