tinyc - A Small C Compiler

tinyc is a small C compiler written in Rust. It uses LLVM 21 for code generation and optimization.

Project Structure

• src/lexer — Lexical analysis: breaks source code into tokens.
• src/parser — Parsing: constructs an AST from tokens.
• src/codegen — LLVM IR code generation, optimization, and AOT compilation.

Current Status

The compiler supports:

• Lexer — Keywords, identifiers, integer/float/bool/char literals, all standard operators, and accurate line/column tracking.
• Parser — Recursive-descent parser with correct operator precedence. Supports variable/function declarations, if/else, while loops, return, blocks, and nested expressions.
• Codegen — Full LLVM IR generation for all AST nodes including arithmetic, comparisons, assignments, if/else, while loops, and function definitions.
• Optimization — Runs the LLVM O3 pass pipeline (mem2reg, inlining, GVN, instcombine, loop optimizations, etc.).
• AOT Compilation — Compiles source to a native executable via LLVM object file emission and system linker.

Building

Requires LLVM 21 (llvm21 on Arch, or set LLVM_SYS_211_PREFIX).

cargo build

Usage

# Compile to executable (output name = input without extension)
cargo run -- program.tinyc

# Compile to a specific output path
cargo run -- program.tinyc -o myprogram

# Dump unoptimized LLVM IR to stderr
cargo run -- program.tinyc --emit-ir

Testing

cargo test

Example

int main() {
    int sum = 0;
    int i = 0;
    while (i < 10) {
        sum = sum + i;
        i = i + 1;
    }
    return sum;
}