aeswiki

AESWiki scrapes the AES Sbox Wikipedia page checking the SBox/Inverse tables bytes match the given C++ init bytes on the page. https://en.wikipedia.org/wiki/Rijndael_S-box

Uses goquery to scrape the pre tags.

Possible speed ups:

1. Set initial capacity for the buffers returned in parseSBox* functions (done)
2. Move away from strings and use bytes from (Scanner).Bytes() to reduce allocations (not needed)
3. Remove the prees map and run each parseSBox* in parallel

Profiling 1.aeswiki.bench0 - Benchmark stats after completing (#1) above

$ go test -bench=BenchmarkParse PASS BenchmarkParseSBoxTable-4 100000 21976 ns/op 7200 B/op 83 allocs/op BenchmarkParseSBoxBytes-4 30000 53323 ns/op 12080 B/op 132 allocs/op ok github.com/alexmullins/aeswiki 4.577s

2.After profiling both functions, most of the cumulative time was spent in the Replace func. After testing the Replace() in the strings and bytes packages there was little to no performance difference to warrant a change.

$ go test -bench=BenchmarkReplace PASS BenchmarkReplaceString-4 10000000 204 ns/op 32 B/op 2 allocs/op BenchmarkReplaceByte-4 10000000 203 ns/op 16 B/op 1 allocs/op ok github.com/alexmullins/aeswiki 4.513s

Above there is no timing difference, half the bytes/op and allocs/op. The string.Replace is fine for this use case.