Rust GCC back end: Why and how
3 days ago
- #Rust
- #Compiler
- #GCC
- Rust compiler uses different backends like LLVM, GCC, and Cranelift to generate binary code.
- Compilers convert source code into an Abstract Syntax Tree (AST) through multiple passes.
- Front-end handles parsing, linting, type-checking, and borrow-checking; back-end translates AST to processor instructions.
- GCC backend (rustc_codegen_gcc) is a bridge between Rust's AST and GCC's codegen API, unlike gccrs which is a separate front-end.
- libgccjit allows using GCC for code generation, with Rust bindings available for easier integration.
- Rust backends can optimize code by adding attributes like nonnull to references, improving performance.
- Example shows how Rust's knowledge of non-null references allows GCC to skip unnecessary checks.