cargo-asm

cargo-asm

Displays the generated assembly for specific Rust functions.

Usage

cargo asm [OPTIONS] <PATH>

Where <PATH> is a function path like crate::module::function or a partial match.

Common Workflows

View assembly for a function

cargo asm my_crate::hot_loop

List all available symbols

cargo asm --lib

Show with source interleaved

cargo asm --rust my_crate::function

Check specific target features

RUSTFLAGS="-C target-cpu=native" cargo asm my_crate::simd_fn

Key Options

• --rust - Interleave Rust source with assembly
• --lib - Analyze library target (vs binary)
• --bin <NAME> - Analyze specific binary
• --release - Use release profile (default)
• --dev - Use dev profile
• --target <TRIPLE> - Cross-compile target

Tips

• Always use --release (or it's on by default) to see optimized output
• Use --rust to understand which source lines map to which instructions
• Look for vmov, vpadd, etc. to verify SIMD vectorization
• Missing function? Try --lib or check if it was inlined