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diff --git a/vendor/crc32fast/README.md b/vendor/crc32fast/README.md deleted file mode 100644 index b0a4827..0000000 --- a/vendor/crc32fast/README.md +++ /dev/null @@ -1,93 +0,0 @@ -# crc32fast [![Build Status][travis-img]][travis] [![Crates.io][crates-img]][crates] [![Documentation][docs-img]][docs] - -[travis-img]: https://travis-ci.com/srijs/rust-crc32fast.svg?branch=master -[travis]: https://travis-ci.com/srijs/rust-crc32fast -[crates-img]: https://img.shields.io/crates/v/crc32fast.svg -[crates]: https://crates.io/crates/crc32fast -[docs-img]: https://docs.rs/crc32fast/badge.svg -[docs]: https://docs.rs/crc32fast - -_Fast, SIMD-accelerated CRC32 (IEEE) checksum computation_ - -## Usage - -### Simple usage - -For simple use-cases, you can call the `hash` convenience function to -directly compute the CRC32 checksum for a given byte slice: - -```rust -let checksum = crc32fast::hash(b"foo bar baz"); -``` - -### Advanced usage - -For use-cases that require more flexibility or performance, for example when -processing large amounts of data, you can create and manipulate a `Hasher`: - -```rust -use crc32fast::Hasher; - -let mut hasher = Hasher::new(); -hasher.update(b"foo bar baz"); -let checksum = hasher.finalize(); -``` - -## Performance - -This crate contains multiple CRC32 implementations: - -- A fast baseline implementation which processes up to 16 bytes per iteration -- An optimized implementation for modern `x86` using `sse` and `pclmulqdq` instructions -- An optimized implementation for `aarch64` using `crc32` instructions - -Calling the `Hasher::new` constructor at runtime will perform a feature detection to select the most -optimal implementation for the current CPU feature set. - -| crate | version | variant | ns/iter | MB/s | -| ----------------------------------- | ------- | --------- | ------- | ---- | -| [crc](https://crates.io/crates/crc) | 1.8.1 | n/a | 4,926 | 207 | -| crc32fast (this crate) | 1.0.0 | baseline | 683 | 1499 | -| crc32fast (this crate) | 1.0.0 | pclmulqdq | 140 | 7314 | - -## Memory Safety - -Due to the use of SIMD intrinsics for the optimized implementations, this crate contains some amount of `unsafe` code. - -In order to ensure memory safety, the relevant code has been fuzz tested using [afl.rs](https://github.com/rust-fuzz/afl.rs) with millions of iterations in both `debug` and `release` build settings. You can inspect the test setup in the `fuzz` sub-directory, which also has instructions on how to run the tests yourself. - -On top of that, every commit is tested using an address sanitizer in CI to catch any out of bounds memory accesses. - -Even though neither fuzzing nor sanitization has revealed any safety bugs yet, please don't hesitate to file an issue if you run into any crashes or other unexpected behaviour. - -## Available feature flags - -### `std` (default: enabled) - -This library supports being built without the Rust `std` library, which is useful for low-level use-cases such as embedded where no operating system is available. To build the crate in a `no_std` context, disable the default `std` feature. - -Note: Because runtime CPU feature detection requires OS support, the specialized SIMD implementations will be unavailable when the `std` feature is disabled. - -### `nightly` (default: disabled) - -This feature flag enables unstable features that are only available on the `nightly` channel. Keep in mind that when enabling this feature flag, you -might experience breaking changes when updating compiler versions. - -Currently, enabling this feature flag will make the optimized `aarch64` implementation available. - -## License - -This project is licensed under either of - -- Apache License, Version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or - http://www.apache.org/licenses/LICENSE-2.0) -- MIT license ([LICENSE-MIT](LICENSE-MIT) or - http://opensource.org/licenses/MIT) - -at your option. - -### Contribution - -Unless you explicitly state otherwise, any contribution intentionally submitted -for inclusion in this project by you, as defined in the Apache-2.0 license, -shall be dual licensed as above, without any additional terms or conditions. |