Compiler Explorer

Source code

using System;
using System.Numerics;
using System.IO;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;
using CompilerExplorer;

interface IHex
{
    abstract static int Value { get; }
}

interface INum<T>
{
    abstract static T Value { get; }
}

struct Hex0 : IHex
{
    public static int Value => 0;
}

struct Hex1 : IHex
{
    public static int Value => 1;
}

struct Hex2 : IHex
{
    public static int Value => 2;
}

struct Hex3 : IHex
{
    public static int Value => 3;
}

struct Hex4 : IHex
{
    public static int Value => 4;
}

struct Hex5 : IHex
{
    public static int Value => 5;
}

struct Hex6 : IHex
{
    public static int Value => 6;
}

struct Hex7 : IHex
{
    public static int Value => 7;
}

struct Hex8 : IHex
{
    public static int Value => 8;
}

struct Hex9 : IHex
{
    public static int Value => 9;
}

struct HexA : IHex
{
    public static int Value => 10;
}

struct HexB : IHex
{
    public static int Value => 11;
}

struct HexC : IHex
{
    public static int Value => 12;
}

struct HexD : IHex
{
    public static int Value => 13;
}

struct HexE : IHex
{
    public static int Value => 14;
}

struct HexF : IHex
{
    public static int Value => 15;
}

struct Int<H7, H6, H5, H4, H3, H2, H1, H0> : INum<int>
    where H7 : IHex
    where H6 : IHex
    where H5 : IHex
    where H4 : IHex
    where H3 : IHex
    where H2 : IHex
    where H1 : IHex
    where H0 : IHex
{
    public static int Value
    {
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        get => H7.Value << 28 | H6.Value << 24 | H5.Value << 20 | H4.Value << 16 | H3.Value << 12 | H2.Value << 8 | H1.Value << 4 | H0.Value;
    }
}

interface IOp
{
    abstract static int Run(int address, Span<byte> memory, Stream input, Stream output);
}

struct Stop : IOp
{
    [MethodImpl(MethodImplOptions.AggressiveInlining)]
    public static int Run(int address, Span<byte> memory, Stream input, Stream output)
    {
        return address;
    }
}

struct Loop<Body, Next> : IOp
    where Body : IOp
    where Next : IOp
{
    [MethodImpl(MethodImplOptions.AggressiveInlining)]
    public static int Run(int address, Span<byte> memory, Stream input, Stream output)
    {
        while (memory.UnsafeAt(address) != 0)
        {
            address = Body.Run(address, memory, input, output);
        }
        return Next.Run(address, memory, input, output);
    }
}

struct AddPointer<Offset, Next> : IOp
    where Offset : INum<int>
    where Next : IOp
{
    [MethodImpl(MethodImplOptions.AggressiveInlining)]
    public static int Run(int address, Span<byte> memory, Stream input, Stream output)
    {
        return Next.Run(address + Offset.Value, memory, input, output);
    }
}

[GenericArguments(
    typeof(Int<Hex0, Hex0, Hex0, Hex0, Hex0, Hex0, Hex3, Hex1>),
    typeof(AddPointer<Int<Hex0, Hex0, Hex0, Hex0, Hex0, Hex0, Hex0, Hex1>, AddData<Int<Hex0, Hex0, Hex0, Hex0, Hex0, Hex0, Hex3, Hex2>, AddPointer<Int<Hex0, Hex0, Hex0, Hex0, Hex0, Hex0, Hex0, Hex1>, AddData<Int<Hex0, Hex0, Hex0, Hex0, Hex0, Hex0, Hex3, Hex3>, AddPointer<Int<HexF, HexF, HexF, HexF, HexF, HexF, HexF, HexE>, OutputData<AddPointer<Int<Hex0, Hex0, Hex0, Hex0, Hex0, Hex0, Hex0, Hex1>, OutputData<AddPointer<Int<Hex0, Hex0, Hex0, Hex0, Hex0, Hex0, Hex0, Hex1>, OutputData<Stop>>>>>>>>>>)
)]
struct AddData<Data, Next> : IOp
    where Data : INum<int>
    where Next : IOp
{
    [MethodImpl(MethodImplOptions.AggressiveInlining)]
    public static int Run(int address, Span<byte> memory, Stream input, Stream output)
    {
        memory.UnsafeAt(address) += (byte)Data.Value;
        return Next.Run(address, memory, input, output);
    }
}

struct OutputData<Next> : IOp
    where Next : IOp
{
    [MethodImpl(MethodImplOptions.AggressiveInlining)]
    public static int Run(int address, Span<byte> memory, Stream input, Stream output)
    {
        output.WriteByte(memory.UnsafeAt(address));
        return Next.Run(address, memory, input, output);
    }
}

struct InputData<Next> : IOp
    where Next : IOp
{
    [MethodImpl(MethodImplOptions.AggressiveInlining)]
    public static int Run(int address, Span<byte> memory, Stream input, Stream output)
    {
        var data = input.ReadByte();
        if (data == -1)
        {
            return address;
        }
        memory.UnsafeAt(address) = (byte)data;
        return Next.Run(address, memory, input, output);
    }
}

static class SpanExtensions
{
    internal static ref T UnsafeAt<T>(this Span<T> span, int address)
    {
        return ref Unsafe.Add(ref MemoryMarshal.GetReference(span), address);
    }
}