Commits on Jan 12, 2024

1. JIT: Factor reachability sets and base them on new DFS …

   - Introduce `BlockReachabilitySets` which encapsulates a data structure
     that can answer "A -> B" reachability queries in `O(1)`. It factors
     the old `fgComputeReachabilitySets` and `fgReachable`.
   - Base the new reachability sets on the new DFS instead of using the old
     DFS. Switch to postorder num indexing instead of bbNum based indexing.
   - Remove `BasicBlock::bbReach`; store the reachability sets within
     `BlockReachabilitySets` instead. This costs some extra memory in
     FullOpts if we end up computing it twice, but reduces memory in
     MinOpts.
   - We no longer propagate `BBF_GC_SAFE_POINT` during the reachability
     computation. The cycle-based GC safe point algorithm introduced in
     dotnet#95299 does not require this propagation.
   - Switch the dead block elimination in `fgComputeReachability` to use
     `fgDfsBlocksAndRemove`, which has more general handling of EH and does
     not require as much iteration to closure
   - Remove the compuation of "enter blocks". With recent work the
     reachability computation was the last remaining use.
   
   Minor diffs expected due to the more general dead block removal capacity
   of `fgDfsBlocksAndRemove`.

   

   jakobbotsch committed Jan 12, 2024
   Configuration menu

   • View commit details
   • Copy full SHA for a0556e2
   • Browse repository at this point

   Copy the full SHA

   a0556e2 View commit details

   Browse the repository at this point in the history