Lab Project of Compilers - FIB UPC, 2025

The lab project will consist of building a compiler for an simplified imperative language named ASL (standing for A Simple Language).

The project will consist of:

• Writting a grammar for the language, and use ANTLR4 to generate a parser in C++

• Writting a semantic check module (in C++) that performs semantic analysis (i.e. variable type checking) on the tree produced by the parser on a given input program.

• Writting a code generation module (in C++) that generates low-level code for the input program. We will generate simple 3-address code that will run on a custom virtual machine called tVM (standing for t-code Virtual Machine).

In order to do the work, you will have some help:

• You will be using ANTLR-4, a powerful tool that will make it much easier to build your compiler.

• You will be provided with a basic working compiler (with just assignment instructions and sum operations) which you will need to complete until your ASL compiler is finished.

• You will also be provided with some auxiliary modules to help manage the data structures required to build the compiler.

• Finally, you will be provided with a list of ASL programs to incrementally test your compiler.

Warning

Auxiliary modules may change from one course to the next. If you are re-taking the course, your lab project may not work with this year modules. Exams will be compiled with current versions, so if you want to re-use code from last year, make sure you adapt it to be compatible with the latest versions of the auxiliary modules.

Here you will find further documentation about:

• The target language, ASL

• The provided compiler skeleton and auxiliary modules

• Summary of basic usage of ANTLR ParseTree API

• The description of tVM machine and the language it can execute

• The description of incremental program tests

You can also download the required code (also available at /assig/$USER/cl/files/CL-lab.tgz in FIB labs):

• Project base files.

Project Evaluation

Although the project is to be carried out in teams of two people, the evaluation will be individual.

The project will be evaluated in two exams (one mid-term, the other final). Each exam will consist of implemeting an extension to the language supported by compiler developed along the course.

Exams from previous years are available for practicing.