[PATCH] D28767: Do not verify Dominator tree if it has no roots

[Chad Rosier via Phabricator via llvm-commits]

mcrosier added a comment.

This seems reasonable to me, but I've added more reviews to see if they have any additional feedback.

IIRC, when I wrote the patch to add the verifyDomTree function here it was taken verbatim from the IR level dominator tree verifier.  Therefore, it might be a good idea to make a similar change to the IR-level verifier.



================
Comment at: lib/CodeGen/MachineDominators.cpp:147
+  if (getRoots().empty())
+    // If no roots found in the dominator tree, the pass that builds it is
+    // likely to be skipped.
----------------
I'd probably drop this comment in favor of the title of this revision, "Do not verify Dominator tree if it has no root." 


https://reviews.llvm.org/D28767