What for?

For compiling Latte programs to x64.

Why?

The compiler construction course at MIMUW.

But what is Latte?

A simple Java-like object-oriented language. Some of its features:

1. 32-bit signed integeres, booleans, on-heap strings, arrays and user-defined classes.
2. Virtual methods.
3. Very simple IO through builtin readInt, readString, printInt, printString methods. For some examples of correct Latte programs, see test_inputs/good directory.

Technicalities

This compiler is written in Rust programming language. It uses LALRPOP for generating a parser. The file src/grammar.lalrpop contains the grammar used by LALRPOP to generate Rust code during compilation (see build.rs).

Implemented code optimizations:

1. Const propagation
2. Dead code removal
3. GCSE
4. Linear register allocation

Compilation:

1. The input program is parsed into an AST using the parser generated with LALRPOP
2. The AST is statically checked and simplified (e.g. for loops are transformed into while loops with anonymous variables) - src/frontend module
3. Each function definition is transformed into a high-level intermediate SSA representation modeled after LLVM - src/middlend module
4. Intermediate representation is transformed into x64 assembly in nasm format - src/backend module
5. x64 assembly is processed using nasm executable and linked with Latte runtime with gcc

Building

Command make produces compilation artifacts in both target and runtime directories. To compile the project, make uses gcc and cargo - the standard package manager for Rust.

Apart from building the compiler, make also builds the Latte runtime. The source code for that is located in lib/runtime.c.

Running the compiler requires compiled Latte runtime, gcc and nasm. For more info, see cargo run -- --help.