Revert "Merge pull request #251 from mlemanczyk/codex/refactor-prime-checking-on-gpu-n5t2pm"

This reverts commit 936ce239db, reversing
changes made to e14b77e504.

PerfectNumbers.Core/Gpu/Kernels/PrimeTesterKernels.cs

@@ -1,19 +1,9 @@
 using System.Runtime.CompilerServices;
 using ILGPU;
 using ILGPU.Algorithms;
-using ILGPU.Runtime;
 
 namespace PerfectNumbers.Core.Gpu;
 
-internal enum HeuristicGpuDivisorTableKind : byte
-{
-    GroupA = 0,
-    GroupBEnding1 = 1,
-    GroupBEnding7 = 7,
-    GroupBEnding9 = 9,
-    Combined = 255,
-}
-
 internal static class PrimeTesterKernels
 {
     // GPU kernel: small-prime sieve only. Returns 1 if passes sieve (probable prime), 0 otherwise.
@@ -61,13 +51,13 @@ internal static class PrimeTesterKernels
         int length = (int)primes.Length;
         for (int i = 0; i < length; i++)
         {
+            ulong prime = primes[i];
             ulong primeSquare = primeSquares[i];
             if (primeSquare > n)
             {
                 break;
             }
 
-            ulong prime = primes[i];
             if (n % prime == 0UL)
             {
                 result = 0;
@@ -78,31 +68,19 @@ internal static class PrimeTesterKernels
         results[index] = result;
     }
 
-    public static void HeuristicTrialDivisionKernel(
-        Index1D index,
-        ArrayView<int> resultFlag,
-        ulong n,
-        ulong maxDivisorSquare,
-        HeuristicGpuDivisorTableKind tableKind,
-        HeuristicGpuDivisorTables tables)
+    public static void HeuristicTrialDivisionKernel(Index1D index, ArrayView<ulong> divisors, ulong n, ArrayView<int> resultFlag)
     {
-        byte nMod10 = (byte)(n % 10UL);
-        ArrayView1D<ulong, Stride1D.Dense> divisors = tables.SelectDivisors(tableKind, nMod10);
-        ArrayView1D<ulong, Stride1D.Dense> divisorSquares = tables.SelectDivisorSquares(tableKind, nMod10);
+		ulong divisor = divisors[index];
+		if (divisor <= 1UL)
+		{
+			return;
+		}
 
-        int divisorLength = (int)divisorSquares.Length;
-        int threadIndex = index;
-        bool skipThread = threadIndex >= divisorLength;
-        ulong divisorSquare = skipThread ? 0UL : divisorSquares[threadIndex];
-        skipThread = skipThread | (divisorSquare > maxDivisorSquare);
-
-        ulong divisor = skipThread ? 1UL : divisors[threadIndex];
-        ulong remainder = skipThread ? 1UL : n % divisor;
-        bool hasFactor = !skipThread & (remainder == 0UL);
-        if (hasFactor)
-        {
-            resultFlag[0] = 1;
-        }
+		ulong residue = n % divisor;
+		if (residue == 0UL)
+		{
+			resultFlag[0] = 1;
+		}
     }
 
     public static void SharesFactorKernel(Index1D index, ArrayView<ulong> numbers, ArrayView<byte> results)