message: [XLA] Don't implement kCrossReplicaSum case in HloInstruction::IdenticalSlowPath.
diff: @@ -1493,10 +1493,6 @@ bool HloInstruction::IdenticalSlowPath(
  return protobuf_util::ProtobufEquals(padding_config(),
  other.padding_config());
  case HloOpcode::kCall:
  - case HloOpcode::kCrossReplicaSum:
  - return replica_group_ids() == other.replica_group_ids() &&
  - cross_replica_sum_barrier() == other.cross_replica_sum_barrier() &&
  - eq_computations(to_apply(), other.to_apply());
  case HloOpcode::kCustomCall:
  if ((window_ == nullptr) != (other.window_ == nullptr) ||
  (window_ != nullptr &&
  @@ -1547,6 +1543,7 @@ bool HloInstruction::IdenticalSlowPath(
  case HloOpcode::kReducePrecision:
  case HloOpcode::kInfeed:
  case HloOpcode::kOutfeed:
  + case HloOpcode::kCrossReplicaSum:
  LOG(FATAL) << "Base class impl called for opcode with subclass: "
  << opcode();
  }
  