minic

Compiler for a small subset of the C programming language that uses Megaparsec for parsing and llvm-hs for code generation.

Goals

This compiler was written for a university compiler construction course and as a learning experiment.

Features

Current features of the compiler include:

Functions
Parameters, return statements
Recursion
Command line arguments for main function
If Else statements
While statements
Line (//) and block (/**/) comments
Globals
Variable declarations, assignments
Variable scopes
Arrays (one-dimensional assignments, multidimensional parsing and declarations)
boolean comparison operators: "<", ">", "=="
Arithmetic operators: +, -, *, /
types: int, char, void
pointer declarations
Simple non-c print statements for ints

Also has stricter typechecker that checks e.g. function return types and distinguishes chars and ints.

Building

You will need llvm installed. For installation instructions check e.g.: https://github.com/llvm-hs/llvm-hs/blob/llvm-9/README.md#installing-llvm.

There is no linker included so you will need e.g. gcc to link object files.

To build with stack:

$ stack build

To run tests:

$ stack test

Running

Run the compiler with an example file to produce an object file 'minic':

$ stack exec minic-exe /path/to/file

Link and compile the generated object file with e.g. gcc:

$ gcc runtime.c minic

The compiler can also be run as a REPL for debugging. It outputs the LLVM representation of the program on the screen but does not compile to a file.

To run REPL:

$ stack exec minic-exe

Examples

Example files of the compilers functionality can be found in the examples folder.

Print statements

Prints expressions that eval to ints. Are not actual C functions.

grammar: 'print' '(' expr ')'

These are mainly just to get easy information of programs while running. Functionality is provided by a C function that is in "runtime.c" and linked together with the output of minic.