Simplify dead code lint This PR scratches a few itches I had when looking at that code. The perf improvement comes from keeping the `scanned` set through several marking phases. This pretty much divides by 2 the number of HIR traversals.
Simplify dead code lint This PR scratches a few itches I had when looking at that code. The perf improvement comes from keeping the `scanned` set through several marking phases. This pretty much divides by 2 the number of HIR traversals.