message: Remove unnecessary check from temporal_order
diff: @@ -382,30 +382,10 @@ fn temporal_order(ctx: &Context, src: Inst, dest: Inst) -> TemporalOrder {
  debug_assert_ne!(src, dest);
  if ctx.domtree.dominates(src, dest, &ctx.func.layout) {
  - return TemporalOrder::DefinitivelyBefore;
  + TemporalOrder::DefinitivelyBefore
  } else if ctx.domtree.dominates(src, dest, &ctx.func.layout) {
  - return TemporalOrder::NeverBefore;
  - }
  -
  - let src_ebb = ctx.func.layout.inst_ebb(src).unwrap();
  - let dest_ebb = ctx.func.layout.inst_ebb(dest).unwrap();
  -
  - // FIXME O(stack_load count * ebb count)
  - // FIXME reuse memory allocations
  - let mut visited = EntitySet::new();
  - let mut todo = EntitySet::new();
  - todo.insert(dest_ebb);
  - while let Some(ebb) = todo.pop() {
  - if visited.contains(ebb) {
  - continue;
  - }
  - visited.insert(ebb);
  - if ebb == src_ebb {
  - return TemporalOrder::MaybeBefore;
  - }
  - for bb in ctx.cfg.pred_iter(ebb) {
  - todo.insert(bb.ebb);
  - }
  - }
  TemporalOrder::NeverBefore
  + } else {
  + TemporalOrder::MaybeBefore
  + }
  }
  