// Get the estimated cost for the op under the given hardware spec senario.
float GetCostForOp(Operation* op, const std::string& hardware);

// Get the estimated cost for the whole function under the given hardware.
float GetCostForFunc(func::FuncOp* func, const std::string& hardware);

// Get the transfer cost given from & to hardware info.
// We will only calculate for the "necessary" tensor transferred.

    auto target = GetTargetAnnotation(func);
    if (!target.has_value()) {
      func.emitError("we cannot get hardware info for this function.");
      signalPassFailure();
    }

    float total_cost = GetCostForFunc(&func, *target);
    OpBuilder builder(func);
    UpdateCost(func, total_cost, &builder);
  }
}

}  // namespace

std::unique_ptr<OperationPass<ModuleOp>> CreateComputeCostPass() {

  auto* device_hardware = GetTargetHardware(hardware);
  if (device_hardware == nullptr) {
    return kDefaultFixedValuedCost;
  }

  return device_hardware->GetOpCost(op);
}

float GetCostForFunc(func::FuncOp* func, const std::string& hardware) {
  auto* device_hardware = GetTargetHardware(hardware);
  if (device_hardware == nullptr) {
    return kDefaultFixedValuedCost;
  }