COMPILER

A compiler apparatus enables description of a particular hardware module in the existing programming language, although the description has not been possible in hardware designing to input programming language. In the header file 24, a particular hardware indescribable in programming language is defined. And the compiler apparatus includes a parser unit 30 analyzing syntax of source program 22, an intermediate code converting unit 32 converting the syntactically analyzed source program 22 to an intermediate code and code generating unit 36 converting the intermediate code to the RTL description. The intermediate code converting unit 32 includes a detecting unit 40 detecting a particular hardware defined in the header file 24 out of the source program 22 and a replacing unit 42 replacing the detected particular hardware in the detecting unit 40 with the intermediate code corresponding to a particular hardware.