Compiler for Rust

A Rust-based compiler construction project for CS441. The repository is organized as a Cargo workspace with separate crates for common compiler data structures, frontend parsing/tokenization, IR, backend lowering, and the command-line interface.

Project Goals

• Parse source programs into structured compiler representations.
• Convert frontend output into an intermediate representation.
• Lower IR toward executable-style control flow and runtime behavior.
• Support required runtime checks for tagged values.
• Implement and document at least one local optimization pass.
• Keep the workspace modular enough to test individual compiler stages.

Workspace Layout

.
|-- Cargo.toml
|-- crates/
|   |-- compiler-cli/        # Command-line entry point
|   |-- compiler-common/     # Shared tokens/statements/data types
|   |-- compiler-frontend/   # Tokenizer and parser
|   |-- compiler-ir/         # Intermediate representation and printing
|   `-- compiler-backend/    # Lowering/backend work
|-- docs/
|   |-- WORKSPACE_STRUCTURE.md
|   `-- dev_journal/
`-- tests/

Implemented Areas

• Multi-crate Rust workspace
• Token and statement data structures
• Frontend tokenizer/parser modules
• Intermediate representation modules
• Backend lowering module structure
• CLI crate for compiler execution
• Unit tests for tokens, tokenizer behavior, and library components

Course Requirements Being Targeted

Requirement	Notes
Source to AST conversion	Parse supported language constructs correctly.
AST to CFG	Preserve runtime behavior in control-flow form.
Runtime tag checks	Detect invalid pointer/integer operations where required.
CFG to SSA	Convert control flow into SSA using phi nodes.
Peephole optimization	Implement a local optimization that can be disabled with -noopt.
IR output	Emit the expected data, code, and main sections.
Demonstration scripts	Include examples that show the optimization has an observable effect.

Expected Usage

The final compiler is expected to support commands in this shape:

./comp p.441 > p.ir
./comp -noopt p.441 > p.ir

Development

Run tests with:

cargo test

Build the workspace with:

cargo build

Notes

This repository is both a course project and a systems-learning artifact. The goal is to keep the implementation understandable, tested by stage, and documented honestly as compiler features are completed.