resources_.erase(resource);
    written_resources_.remove(resource);
  }

  // Replaces all resource loads in all regions attached to the op.
  void ReplaceResourceLoads(bool read_only) {
    llvm::for_each(op_->getRegions(), [&](Region& region) {
      ReplaceResourceLoads(region, read_only);
    });
  }

  static LogicalResult ReplaceOpWithNewOp(Operation* op);

 private:
  // Returns if any resources need lifting.