Initial PollardRho implementation for GPU. Added pool for accelerator streams shared across the threads. GPU processing performance and stabilization improvements. GpuUInt128.BinaryGcd switched to the version which outperformed other in benchmarks.

PerfectNumbers.Core/Gpu/DeterministicRandomGpu.cs

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+using System.Runtime.CompilerServices;
+using ILGPU;
+
+namespace PerfectNumbers.Core.Gpu;
+
+public static class ThreadStaticDeterministicRandomGpu
+{
+	[ThreadStatic]
+	private static DeterministicRandomGpu? _exclusive;
+	internal static DeterministicRandomGpu Exclusive => _exclusive ?? new DeterministicRandomGpu();
+}
+
+internal struct DeterministicRandomGpu
+{
+	private static long s_seedCounter;
+
+	private ulong _state;
+	public readonly ulong State
+	{
+		[MethodImpl(MethodImplOptions.AggressiveInlining)]
+		get
+		{
+			return _state;
+		}
+	}
+
+	public DeterministicRandomGpu()
+	{
+		_state = CreateThreadState();
+	}
+
+	public DeterministicRandomGpu(ulong initialState)
+	{
+		_state = initialState;
+	}
+
+	public ulong NextUInt64()
+	{
+		ulong state = _state;
+		state ^= state >> 12;
+		state ^= state << 25;
+		state ^= state >> 27;
+		_state = state;
+		return state * 2685821657736338717UL;
+	}
+
+	public GpuUInt128 NextUInt128()
+	{
+		GpuUInt128 high = (GpuUInt128)NextUInt64();
+		ReadOnlyGpuUInt128 low = (ReadOnlyGpuUInt128)NextUInt64();
+		high.ShiftLeft(64);
+		high.Add(low);
+		return high;
+	}
+
+	public void SetState(ulong state)
+	{
+		_state = state;
+	}
+
+	private static ulong CreateThreadState()
+	{
+		ulong seed = (ulong)Atomic.Add(ref s_seedCounter, 1);
+		seed += 0x9E3779B97F4A7C15UL;
+		seed = (seed ^ (seed >> 30)) * 0xBF58476D1CE4E5B9UL;
+		seed = (seed ^ (seed >> 27)) * 0x94D049BB133111EBUL;
+		seed ^= seed >> 31;
+		if (seed == 0UL)
+		{
+			seed = 0x9E3779B97F4A7C15UL;
+		}
+
+		return seed;
+	}
+}