Reapply modulo helpers and inline fast remainders

EvenPerfectBitScanner.Benchmarks/Mod6ULongBenchmarks.cs

@@ -0,0 +1,43 @@
+using System.Numerics;
+using BenchmarkDotNet.Attributes;
+using BenchmarkDotNet.Jobs;
+using PerfectNumbers.Core;
+
+namespace EvenPerfectBitScanner.Benchmarks;
+
+[SimpleJob(RuntimeMoniker.Net80, launchCount: 1, warmupCount: 1, iterationCount: 3)]
+[MemoryDiagnoser]
+public class Mod6ULongBenchmarks
+{
+    private static readonly ulong Divisor = 6UL;
+    private static readonly ulong FastDivMul = (ulong)(((UInt128)1 << 64) / Divisor);
+
+    [Params(3UL, 131071UL, ulong.MaxValue)]
+    public ulong Value { get; set; }
+
+    [Benchmark(Baseline = true)]
+    public ulong ModuloOperator()
+    {
+                return Value % Divisor;
+    }
+
+    [Benchmark]
+    public ulong DivisionBased()
+    {
+        ulong quotient = Value / Divisor;
+        return Value - quotient * Divisor;
+    }
+
+    [Benchmark]
+    public ulong FastDivHigh()
+    {
+        ulong quotient = Value.FastDiv64(Divisor, FastDivMul);
+        return Value - quotient * Divisor;
+    }
+
+    [Benchmark]
+    public ulong ExtensionMethod()
+    {
+        return Value.Mod6();
+    }
+}