Rust fast &[u8] to integer parser (x86_64 SIMD, SSE4.1, AVX2)

Modified this version (from the article) to perform validation, support various strings of different lengths and negative values.

If you have &str then use .as_bytes()

The 64 bit functions use SSE4.1, max string length is 20 numbers (within u64::MAX–0, i64::MAX–i64::MIN).

The 128 bit functions use AVX2, max string length is 32 numbers (33 with sign).

It needs the target-feature or target-cpu flags for it to build with optimized performance. By default the target-feature is set in ./.cargo/config.toml, but seems like it works only inside this library.

Also you can use one of the following environment variables:

• RUSTFLAGS="-C target-feature=+sse2,+sse3,+sse4.1,+ssse3,+avx,+avx2"

• RUSTFLAGS="-C target-cpu=native"

For Windows PowerShell you can set it with $Env:RUSTFLAGS='-C target-feature=+sse2,+sse3,+sse4.1,+ssse3,+avx,+avx2'

Examples

``` asserteq!(atoisimd::parseu64("0".asbytes(), None).unwrap(), 0u64); asserteq!(atoisimd::parseu64("1234".asbytes(), None).unwrap(), 1234u64);

asserteq!(atoisimd::parsei64("2345".asbytes()).unwrap(), 2345i64); asserteq!(atoisimd::parsei64("-2345".asbytes()).unwrap(), -2345i64);

asserteq!(atoisimd::parseu128("1234".asbytes()).unwrap(), 1234_u128);

asserteq!(atoisimd::parsei128("2345".asbytes()).unwrap(), 2345i128); asserteq!(atoisimd::parsei128("-1234".asbytes()).unwrap(), -1234i128); ```

Benchmarks

You can run cargo bench on your machine.

Results

More information you can find here.