message: [XLA] [NFC] Refactor LiveRangeBefore
  Logging is extraneous, as all callsites to LiveRangeBefore log themselves
  anyway.
diff: @@ -876,30 +876,13 @@ class CopyRemover {
  // We cannot use LiveRangeStrictlyBefore because HloValue::uses() is not
  // updated as copies are removed.
  bool LiveRangeBefore(const ValueNode& a, const ValueNode& b) {
  - VLOG(3) << "Checking live range of " << *a.value << " WRT " << *b.value;
  - bool is_live_range_before = [&] {
  if (a.uses.empty()) {
  VLOG(2) << "Empty uses for " << *a.value;
  return ordering_.IsDefinedBefore(*a.value, *b.value);
  }
  - for (const HloUse* use : a.uses) {
  - VLOG(3) << "Checking use " << *use << " against " << *b.value;
  - if (!ordering_.UseIsBeforeValueDefinition(*use, *b.value, dataflow_)) {
  - VLOG(2) << "Use " << *use << " is NOT before " << *b.value;
  - return false;
  - }
  - VLOG(3) << "Use " << *use << " is before " << *b.value;
  - }
  - return true;
  - }();
  - if (is_live_range_before) {
  - VLOG(2) << " Live range of " << a.value->ToShortString() << " is before "
  - << b.value->ToShortString();
  - } else {
  - VLOG(2) << " Live range of " << a.value->ToShortString()
  - << " is not before " << b.value->ToShortString();
  - }
  - return is_live_range_before;
  + return absl::c_all_of(a.uses, [&](const HloUse* use) {
  + return ordering_.UseIsBeforeValueDefinition(*use, *b.value, dataflow_);
  + });
  }
  // Returns whether 'node' is the last node in its list.
  