The quality of the input system model has a direct bearing on the effectiveness of the system exploration and synthesis tools. Given a well-structured system model, tools today are effective in generating efficient implementations. However, readily available reference C codes are not conducive for system synthesis as they lack the necessary structure and analyzability needed by the design flow. Usually reference C code is manually converted into a SoC model by applying necessary transformations. The type of transformations depends on the underlying design flow and tools. Proper structural hierarchy is one essential feature needed for architectural exploration. In this paper, we provide automatic C code transformations to encapsulate functions and insert structural hierarchy to create well-structured and analyzable SoC models. Our automatic transformations, combined with interactive application of the designer's knowledge and experience, enable faster creation of structural hierarc...