Worked on enabling advanced cache-line flush optimizations for x86 architectures across the ferrocene/ferrocene, rust-lang/stdarch, and rust-lang/rust repositories. Developed and integrated the CLFLUSHOPT intrinsic, focusing on safe usage patterns, feature gating, and runtime detection using Rust. Enhanced documentation and standardized API signatures to ensure ABI consistency and cross-crate reliability, while updating tests to validate feature detection and usage. Emphasized low-level systems programming and performance optimization, aligning core_arch and stdarch with unadjusted ABI requirements. The work improved developer confidence in leveraging CLFLUSHOPT by providing robust documentation, comprehensive test coverage, and consistent exposure of intrinsics across multiple Rust codebases.