@Override
  public OperationResult execute(final MessageFrame frame, final EVM evm) {
    final long cost = gasCalculator().getTransientLoadOperationGasCost();
    try {
      final Bytes32 slot = UInt256.fromBytes(frame.popStackItem());
      if (frame.getRemainingGas() < cost) {
        return new OperationResult(cost, ExceptionalHaltReason.INSUFFICIENT_GAS);
      } else {
        frame.pushStackItem(frame.getTransientStorageValue(frame.getRecipientAddress(), slot));

        return new OperationResult(cost, null);
      }
    } catch (final UnderflowException ufe) {
      return new OperationResult(cost, ExceptionalHaltReason.INSUFFICIENT_STACK_ITEMS);
    }
  }
TLoad operation

@param gasCalculator gas calculator for costing
evm/src/main/java/org/hyperledger/besu/evm/operation/TLoadOperation.java