Abstract: GNU Compiler Collection(GCC) supports multiple high level languages and multiple platforms with its internal documents and source code opened. It is widely used both in industry and research. GCC supports lots of builtin functions and the implementations of builtin functions are one of the important implementations of GCC. We analyzed the intensions and operations of the builtin functions in GCC. Then, combining with our practical work and taking the vector extension instruction oriented builtin functions as examples, we demonstated the implementation details of plat-form-related builtin functions in GCC. This work is really worth referenced both for the comprehension of the implementation mechanism of builtin functions and for research and development based on GCC.

Key words: GCC,Builtin functions,Anatomy