Cache GPU divisor partial data on GPU path

PerfectNumbers.Core/Gpu/GpuDivisorPartialData.cs

@@ -0,0 +1,38 @@
+using System.Runtime.CompilerServices;
+using PerfectNumbers.Core;
+
+namespace PerfectNumbers.Core.Gpu;
+
+internal readonly struct GpuDivisorPartialData
+{
+    public readonly ulong Modulus;
+    public readonly ReadOnlyGpuUInt128 ModulusWide;
+    private readonly MontgomeryDivisorData _montgomeryData;
+
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    private GpuDivisorPartialData(ulong modulus, ReadOnlyGpuUInt128 modulusWide, in MontgomeryDivisorData montgomeryData)
+    {
+        Modulus = modulus;
+        ModulusWide = modulusWide;
+        _montgomeryData = montgomeryData;
+    }
+
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    public static GpuDivisorPartialData Create(ulong modulus)
+    {
+        MontgomeryDivisorData montgomery = MontgomeryDivisorData.FromModulus(modulus);
+        return new GpuDivisorPartialData(modulus, new ReadOnlyGpuUInt128(modulus), in montgomery);
+    }
+
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    public static GpuDivisorPartialData FromMontgomery(in MontgomeryDivisorData divisor)
+    {
+        return new GpuDivisorPartialData(divisor.Modulus, new ReadOnlyGpuUInt128(divisor.Modulus), in divisor);
+    }
+
+    public MontgomeryDivisorData MontgomeryData
+    {
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        get => _montgomeryData;
+    }
+}