As the scale of digital circuit design increases, design and verification using conventional hardware description languages (HDLs), such as verilog-HDL and VHDL, limit efficiency. Consequently, high level synthesis (HLS), as well as domain specific languages (DSLs), which alternates conventional HDLs, are beginning to garner attention. We proposed a design framework that uses the C language as a register transfer level descriptive language. In this study, we introduced a LLVM compiler infrastructure to extend our previous work, support the C/C++ standard as the input code, and aggressively optimize the circuit design. In addition to supporting a single module generation, we extended our framework to support the hierarchical module description for efficient system design. We demonstrated the conversion of the input of C/C++ code into the verilog code, optimize its logic, and construct pipelined logic to achieve the original behavior in multiple clock cycles. Our framework offers a significantly efficient system-level hardware design and a powerful debugging environment with software development platforms and tool-sets. The generated hardware logic performs as well as or better than hand-written logic using conventional HDLs.