Base58 perfomance patch

[kzorin52]

Description

Various Base58 performance improvements:

Decode():

1. Replaced slow IndexOf() to Base58 character map
2. Replaced .TakeWhile(...).Count() to efficient variant, without memory and cpu-time loss
3. Replaced byte[] Concat() to single Span<byte>
4. Fixed: zeros byte array creation only if decoded is zero

Type of change

• Bug fix (non-breaking change)

How Has This Been Tested?

• UT_Base58.TestEncodeDecode
• UT_StdLib.TestBinary

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas - no hard-to-understand areas
• I have made corresponding changes to the documentation - public API do not changed
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works - benchmarks only
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules - no dependent changes

P.S. It is my first time opening a pull request, please correct me if I've done something wrong.

[Jim8y]

@kzorin52 thank you very much for contributing to neo. This pr looks good to me.

@cschuchardt88 @shargon @AnnaShaleva @vncoelho

[shargon]

Change to char array and avoid cast?

[cschuchardt88]

Char wouldn't work I don't think. Char uses encoding.

[shargon]

Cache length?

[kzorin52]

@shargon all fixed 🥳

[vncoelho]

I tested here and it is working basically.
However, no UTs nor benchmark.

[cschuchardt88]

This needs to optimized with benchmarks data to show that it indeed faster or we can't merge to repo.

This change is not important.

[cschuchardt88]

This cost more in the current code in resources of memory management for the GC in dotnet.

[kzorin52]

@cschuchardt88 Okay, I'll do benchmarks and profiling of the code

[AnnaShaleva]

The optimisation itself is legit, the compatibility is preserved, but you're right in that we need some benchmarks. If possible, then for multiple architectures.

[kzorin52]

I'm sorry, I've been really busy lately. As soon as I have free time, I will be able to make the planned benchmarks.

[shargon]

@cschuchardt88

/* Unmerged change from project 'Neo(net8.0)'
Before:
            -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
            -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
            -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 0, 1, 2, 3, 4, 5, 6,
            7, 8, -1, -1, -1, -1, -1, -1, -1, 9, 10, 11, 12, 13, 14, 15, 16, -1, 17,
            18, 19, 20, 21, -1, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, -1, -1,
            -1, -1, -1, -1, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, -1, 44, 45,
            46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, -1, -1, -1, -1, -1,
After:
            -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
            -1,
            -1,
            -1,
            -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
            -1,
            -1,
            -1,
            -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
            0,
            1,
            2,
            3,
            4,
            5,
            6,
            7,
            8,
            -1, -1, -1, -1,
            -1,
            -1,
            -1,
            9,
            10,
            11,
            12,
            13,
            14,
            15,
            16,
            -1,
            17,
            18,
            19,
            20,
            21,
            -1,
            22,
            23,
            24,
            25,
            26,
            27,
            28,
            29,
            30,
            31,
            32,
            -1,
            -1,
            -1,
            -1,
            -1,
            -1,
            33,
            34,
            35,
            36,
            37,
            38,
            39,
            40,
            41,
            42,
            43,
            -1,
            44,
            45,
            46,
            47,
            48,
            49,
            50,
            51,
            52,
            53,
            54,
            55,
            56,
            57,
            -1, -1,
            -1,
            -1,
            -1,
*/

We have something wrong in the format

[cschuchardt88]

@shargon there is no fix. Its a bug in C# 12.0. If it isnt on a single line, it will format on newline for each element in the array.

Workaround is to wrap

#pragma warning disable format // add this line

        private static readonly int[] s_ints =
        [
            0, 1, 2, 3, 4
        ];

#pragma warning restore format // add this line

[kzorin52]

@cschuchardt88 hi! like this?

[shargon]

It should be good if we hit in tests all the array values