CS 4470 Compilers Template

Use this repository to store your work for CS 4470: Compilers.

To submit assignments, push commits to this repo. They will be graded based on the latest commit up to the deadline (after all granted extensions).

Setup

1. Clone this repository
2. Choose a language
   • If using Python, delete compiler.java and Makefile_java, and rename Makefile_py to Makefile:
     • rm compiler.java Makefile_java
     • mv Makefile_py Makefile
   • If using Java, delete and rename vice-versa
   • If using another language (with instructor permission), create your own Makefile and main file and update GitHub actions accordingly. See "Choosing a Language" below for more info.
3. Inside your clone of template/, clone the grader and runtime repos. Add them to your gitignore. Build the runtime repo too:
   • git clone https://github.com/utah-cs4470-sp25/grader.git
   • echo "grader/\nrt/" >> .gitignore
   • git clone https://github.com/utah-cs4470-sp25/runtime rt; cd rt; make; cd ..;
4. For HW1, make an examples folder too. Put your HW1 work there:
   • mkdir examples

Choosing a Language

This repository supports work in Java (19) or Python (3.10). It correspondingly includes starter files compiler.java and compiler.py. Each starter file compiles and runs, doing nothing and returning successfully. For each language there is also a Makefile: Makefile_java and Makefile_py.

To choose your language, delete the starter files for the other language and rename the remaining Makefile to be named Makefile. If you want to use a language other than Java or Python, you need special permission; contact the instructors. Keep in mind that using another language will be more work, and you will not be able to receive the same level of instructor support. Compilers are complicated. Do not try to learn a new language at the same time as you learn compilers.

Compiling your Compiler

A compiler is just a normal computer program. Before running it you need to compile it. So, once you've chosen a language, compile your compiler by running:

make compile

This should complete without errors. If you get an error, you likely need to install one of javac/java or python3 (depending on the language you chose), or to add those tools to your system PATH. If you're having trouble with this step, please talk to your TA or one of your instructors.

Note that if you are using Python, make compile will do a bit of syntax checking but that's about it. If you are familiar with and want to use tools like Mypy, feel free to edit your Makefile to do so.

Running your Compiler

To test your compiler you need a test program to compile. The file test.jpl is intended to be a quick scratch-pad for such tests. Run your compiler on it with:

make run

Of course, longer-term you'll want to save test files and run the regularly to avoid regressions. You can change the name of the test file like so:

make run TEST=something.jpl

We will use this same functionality to grade your assignments.

Github Actions

Every time you push to this repository, it will compile your program and then auto-grade the current homework assignment. The auto-grader will roll over to the next week's assignment on Monday.

In general, you can feel free to rename files and move them around, but the auto-grader works via Github Actions, which are configured in the .github folder. Do not edit any file in that folder. You will fail the assignment! Also do not create a folder called grader, that will break the autograder.

Github actions will email you every time you push, if you fail a test. This will be most times you push, since "failing a test" just means you haven't finished an assignment. That will be very annoying. We recommend turning this off.