// If the previous block unconditionally falls through to this block and
// this block has no other predecessors, move the contents of this block
// into the prior block. This doesn't usually happen when SimplifyCFG
- // has been used, but it can happen tail duplication eliminates all the
+ // has been used, but it can happen if tail duplication eliminates all the
// non-branch predecessors of a block leaving only the fall-through edge.
// This has to check PrevBB->succ_size() because EH edges are ignored by
// AnalyzeBranch.