This page introduces the compilation model of our language. You are REQUIRED to follow this model in your own compiler implementation.

1. Concatenate user-provided source code with contributed functions (contrib.java)
2. Syntactic analysis
   1. Halt and exit -1 (System.exit(-1)) if any error detected
   2. Build an AST if parsed successfully
3. Semantic analysis
   1. Halt and exit -1 (System.exit(-1)) if any error detected
      1. You are suggested (but not required) to print detailed error messages
   2. Build global environment information if analyzed successfully
4. Translation (IR generation)
5. Code generation (MIPS)
6. Link (concatenate) with your runtime.s