crc-fast support for ext/hash

Hi! We've been developing a versatile and fast crc library in Rust [1] and would like to integrate it into PHP upstream [2]. Concerns were raised that the PR at least needs a discussion here or even an RFC, so here we are! Note, that it's not about bundling a library, but optional support through --with-crc-fast. Following is the gist of the library's README: > World's fastest generic CRC calculator for all known CRC-32 > and CRC-64 variants, as well as bring-your-own custom > parameters, using SIMD intrinsics, which can exceed > 100GiB/s on modern systems. > > Supports acceleration on aarch64, x86_64, and x86 > architectures, plus has a safe non-accelerated table-based > software fallback for others. > > The crc crate is ~0.5GiB/s by default, so this is up to >220X faster. > > This is unique, not just because of the performance, but also > because I couldn't find a single generic SIMD-accelerated > implementation (in any language) which worked for all > known variants, using the Rocksoft model, especially the > "non-reflected" variants. Thanks for your time and consideration! [1] https://github.com/awesomized/crc-fast-rust?tab=readme-ov-file#crc-fast [2] https://github.com/php/php-src/pull/20513 -- Regards, Mike