Which file is the entry of Rust source code?

I get the source code of Rust from GitHub.
So many files in it, I don't know from where I can start to read it.
Is there an entry file that contains a main function?
Thanks for any suggestions.

Well, run_compiler in src/librustc_driver/lib.rs is the first non-trivial main function that gets run when running the compiler. However, I don't really know how helpful that will be.

Thanks´╝î I will start reading from that function.