--mersenne=bydivisor testers and sessions integrated and converted to structs.
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@@ -0,0 +1,111 @@
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using System.Runtime.CompilerServices;
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namespace PerfectNumbers.Core.Cpu;
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public static class ByteExtensions
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{
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[MethodImpl(MethodImplOptions.AggressiveInlining)]
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public static byte AddMod3(this byte value, byte delta)
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{
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const int Modulus = 3;
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int sum = value + delta;
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if (sum >= Modulus)
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{
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sum -= Modulus;
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}
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return (byte)sum;
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}
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[MethodImpl(MethodImplOptions.AggressiveInlining)]
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public static byte AddMod7(this byte value, byte delta)
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{
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const int Modulus = 7;
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int sum = value + delta;
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if (sum >= Modulus)
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{
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sum -= Modulus;
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}
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return (byte)sum;
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}
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[MethodImpl(MethodImplOptions.AggressiveInlining)]
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public static byte AddMod13(this byte value, byte delta)
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{
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const int Modulus = 13;
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int sum = value + delta;
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if (sum >= Modulus)
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{
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sum -= Modulus;
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}
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return (byte)sum;
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}
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[MethodImpl(MethodImplOptions.AggressiveInlining)]
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public static byte AddMod17(this byte value, byte delta)
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{
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const int Modulus = 17;
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int sum = value + delta;
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if (sum >= Modulus)
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{
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sum -= Modulus;
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}
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return (byte)sum;
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}
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[MethodImpl(MethodImplOptions.AggressiveInlining)]
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public static byte AddMod19(this byte value, byte delta)
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{
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const int Modulus = 19;
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int sum = value + delta;
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if (sum >= Modulus)
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{
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sum -= Modulus;
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}
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return (byte)sum;
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}
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[MethodImpl(MethodImplOptions.AggressiveInlining)]
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public static byte AddMod10(this byte value, byte delta)
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{
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const int Modulus = 10;
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int sum = value + delta;
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if (sum >= Modulus)
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{
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sum -= Modulus;
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}
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return (byte)sum;
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}
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[MethodImpl(MethodImplOptions.AggressiveInlining)]
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public static byte AddMod11(this byte value, byte delta)
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{
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const int Modulus = 11;
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int sum = value + delta;
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if (sum >= Modulus)
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{
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sum -= Modulus;
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}
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return (byte)sum;
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}
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[MethodImpl(MethodImplOptions.AggressiveInlining)]
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public static byte AddMod8(this byte value, byte delta)
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{
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return (byte)((value + delta) & 7);
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}
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}
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@@ -0,0 +1,10 @@
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using PerfectNumbers.Core.Gpu;
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namespace PerfectNumbers.Core.Cpu;
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internal struct GpuUInt128WorkSet
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{
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public GpuUInt128 Step;
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public GpuUInt128 Divisor;
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public GpuUInt128 Limit;
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}
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@@ -3,23 +3,31 @@ using PerfectNumbers.Core.Gpu.Accelerators;
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namespace PerfectNumbers.Core.Cpu;
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internal sealed class MersenneCpuDivisorScanSession(PrimeOrderCalculatorAccelerator gpu, ComputationDevice orderDevice) : IMersenneNumberDivisorByDivisorTester.IDivisorScanSession
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{
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private Func<ulong, MontgomeryDivisorData, ulong> _getCycleLength = orderDevice switch
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internal struct MersenneCpuDivisorScanSessionWithCpuOrder() : IMersenneNumberDivisorByDivisorTester.IDivisorScanSession
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{
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ComputationDevice.Gpu => (divisor, divisorData) => DivisorCycleCache.Shared.GetCycleLengthGpu(gpu, divisor, divisorData),
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ComputationDevice.Hybrid => (divisor, divisorData) => DivisorCycleCache.Shared.GetCycleLengthHybrid(gpu, divisor, divisorData),
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_ => static (divisor, divisorData) => DivisorCycleCache.Shared.GetCycleLengthCpu(divisor, divisorData),
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};
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private readonly CycleRemainderStepper _cycleStepper = new();
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private ExponentRemainderStepperCpu? _exponentStepper;
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public void Configure(PrimeOrderCalculatorAccelerator gpu, ComputationDevice orderDevice)
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[MethodImpl(MethodImplOptions.AggressiveInlining | MethodImplOptions.AggressiveOptimization)]
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public readonly void Configure()
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{
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_getCycleLength = orderDevice switch
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}
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private static ulong _hits;
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private static ulong _misses;
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private static void PrintStats(bool wasHit)
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{
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if (wasHit)
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{
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ComputationDevice.Gpu => (divisor, divisorData) => DivisorCycleCache.Shared.GetCycleLengthGpu(gpu, divisor, divisorData),
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ComputationDevice.Hybrid => (divisor, divisorData) => DivisorCycleCache.Shared.GetCycleLengthHybrid(gpu, divisor, divisorData),
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_ => static (divisor, divisorData) => DivisorCycleCache.Shared.GetCycleLengthCpu(divisor, divisorData),
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};
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Interlocked.Increment(ref _hits);
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}
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else
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{
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Interlocked.Increment(ref _misses);
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}
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Console.WriteLine($"MersenneCpuDivisorScanSession, ExponentStepper hits: $_hits, misses: $_misses");
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}
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public bool CheckDivisor(
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@@ -45,7 +53,154 @@ internal sealed class MersenneCpuDivisorScanSession(PrimeOrderCalculatorAccelera
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if (divisorCycle == 0UL)
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{
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divisorCycle = _getCycleLength(divisor, divisorData);
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divisorCycle = DivisorCycleCache.Shared.GetCycleLengthCpu(divisor, divisorData);
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// This never kicks off in production code
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// if (divisorCycle == 0UL)
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// {
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// // DivisorCycleCache guarantees a positive cycle for divisors greater than one.
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// throw new InvalidOperationException($"Divisor cycle solver returned zero for divisor {divisor}.");
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// }
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}
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// Keep these remainder steppers in place so future updates continue reusing the previously computed residues.
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// They are critical for avoiding repeated full Montgomery exponentiation work when scanning divisors.
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CycleRemainderStepper cycleStepper = _cycleStepper;
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cycleStepper.CycleLength = divisorCycle;
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if (cycleStepper.Initialize(primes[0]) == 0UL)
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{
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return true;
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}
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if (_exponentStepper is not { } exponentStepper)
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{
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_exponentStepper = exponentStepper = new(divisorData, divisorCycle);
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}
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else
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{
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if (!exponentStepper.MatchesDivisor(divisorData, divisorCycle))
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{
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_exponentStepper = exponentStepper = new(divisorData, divisorCycle);
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}
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}
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if (exponentStepper.InitializeCpuIsUnity(primes[0]))
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{
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return true;
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}
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for (int i = 1; i < length; i++)
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{
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if (cycleStepper.ComputeNext(primes[i]) != 0UL)
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{
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continue;
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}
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if (exponentStepper.ComputeNextIsUnity(primes[i]))
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{
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return true;
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}
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}
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return false;
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}
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// [MethodImpl(MethodImplOptions.AggressiveInlining)]
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// public void Return() => ThreadStaticPools.ReturnMersenneCpuDivisorSession(this);
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}
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internal struct MersenneCpuDivisorScanSessionWithHybridOrder() : IMersenneNumberDivisorByDivisorTester.IDivisorScanSession
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{
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private PrimeOrderCalculatorAccelerator? _gpu;
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[MethodImpl(MethodImplOptions.AggressiveInlining | MethodImplOptions.AggressiveOptimization)]
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public void Configure(PrimeOrderCalculatorAccelerator gpu)
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{
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_gpu = gpu;
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}
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public bool CheckDivisor(
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ulong divisor,
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in MontgomeryDivisorData divisorData,
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ulong divisorCycle,
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in ReadOnlySpan<ulong> primes)
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{
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int length = primes.Length;
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var gpu = _gpu ?? throw new InvalidOperationException("Session was not configured with an accelerator.");
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if (divisorCycle == 0UL)
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{
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divisorCycle = DivisorCycleCache.Shared.GetCycleLengthHybrid(gpu, divisor, divisorData);
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}
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// Keep these remainder steppers in place so future updates continue reusing the previously computed residues.
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// They are critical for avoiding repeated full Montgomery exponentiation work when scanning divisors.
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var cycleStepper = new CycleRemainderStepper(divisorCycle);
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if (cycleStepper.Initialize(primes[0]) == 0UL)
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{
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return true;
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}
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var exponentStepper = new ExponentRemainderStepperCpu(divisorData, divisorCycle);
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if (exponentStepper.InitializeCpuIsUnity(primes[0]))
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{
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return true;
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}
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for (int i = 1; i < length; i++)
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{
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if (cycleStepper.ComputeNext(primes[i]) != 0UL)
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{
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continue;
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}
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if (exponentStepper.ComputeNextIsUnity(primes[i]))
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{
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return true;
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}
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}
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return false;
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}
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// [MethodImpl(MethodImplOptions.AggressiveInlining)]
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// public void Return() => ThreadStaticPools.ReturnMersenneCpuDivisorSession(this);
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}
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internal struct MersenneCpuDivisorScanSessionWithGpuOrder() : IMersenneNumberDivisorByDivisorTester.IDivisorScanSession
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{
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private PrimeOrderCalculatorAccelerator? _gpu;
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public void Configure(PrimeOrderCalculatorAccelerator gpu)
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{
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_gpu = gpu;
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}
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public bool CheckDivisor(
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ulong divisor,
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in MontgomeryDivisorData divisorData,
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ulong divisorCycle,
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in ReadOnlySpan<ulong> primes)
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{
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int length = primes.Length;
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var gpu = _gpu ?? throw new InvalidOperationException("Session was not configured with an accelerator.");
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// EvenPerfectBitScanner always provides at least one exponent on this path.
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// Keep the guard commented out for tests that might reuse the session differently.
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// if (length == 0)
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// {
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// return false;
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// }
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// This never kicks off in production code
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// if (divisorData.Modulus != divisor)
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// {
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// throw new InvalidOperationException("Divisor data is for a different modulus");
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// // cachedData = MontgomeryDivisorData.FromModulus(divisor);
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// }
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if (divisorCycle == 0UL)
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{
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divisorCycle = DivisorCycleCache.Shared.GetCycleLengthGpu(gpu, divisor, divisorData);
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// This never kicks off in production code
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// if (divisorCycle == 0UL)
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// {
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@@ -84,6 +239,6 @@ internal sealed class MersenneCpuDivisorScanSession(PrimeOrderCalculatorAccelera
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return false;
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}
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[MethodImpl(MethodImplOptions.AggressiveInlining)]
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public void Return() => ThreadStaticPools.ReturnMersenneCpuDivisorSession(this);
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// [MethodImpl(MethodImplOptions.AggressiveInlining)]
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// public void Return() => ThreadStaticPools.ReturnMersenneCpuDivisorSession(this);
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}
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@@ -1,980 +0,0 @@
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using System.Numerics;
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using System.Runtime.CompilerServices;
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using System.Globalization;
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using PerfectNumbers.Core.Gpu;
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using PerfectNumbers.Core.Gpu.Accelerators;
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namespace PerfectNumbers.Core.Cpu;
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public sealed class MersenneNumberDivisorByDivisorCpuTester(ComputationDevice orderDevice = ComputationDevice.Hybrid) : IMersenneNumberDivisorByDivisorTester
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{
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private BigInteger _divisorLimit;
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private int _batchSize = 1_024;
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private BigInteger _minK = BigInteger.One;
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private readonly ComputationDevice OrderDevice = orderDevice;
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private readonly TryCycleLengthDelegate _tryCalculateCycleLengthForExponent = orderDevice switch
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{
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ComputationDevice.Gpu => TryCalculateCycleLengthForExponentGpu,
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ComputationDevice.Hybrid => TryCalculateCycleLengthForExponentHybrid,
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_ => TryCalculateCycleLengthForExponentCpu,
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};
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private readonly CalculateCycleLengthDelegate _calculateCycleLength = orderDevice switch
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{
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ComputationDevice.Gpu => CalculateCycleLengthGpu,
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ComputationDevice.Hybrid => CalculateCycleLengthHybrid,
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_ => CalculateCycleLengthCpu,
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};
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private string? _stateFilePath;
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private int _stateCounter;
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private BigInteger _lastSavedK;
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private delegate bool TryCycleLengthDelegate(
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ulong divisor,
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PrimeOrderCalculatorAccelerator gpu,
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ulong exponent,
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in MontgomeryDivisorData divisorData,
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out ulong cycleLength,
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out bool primeOrderFailed);
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private delegate ulong CalculateCycleLengthDelegate(
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ulong divisor,
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PrimeOrderCalculatorAccelerator gpu,
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in MontgomeryDivisorData divisorData,
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bool skipPrimeOrderHeuristic);
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[ThreadStatic]
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private static GpuUInt128WorkSet _divisorScanGpuWorkSet;
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private struct GpuUInt128WorkSet
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{
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public GpuUInt128 Step;
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public GpuUInt128 Divisor;
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public GpuUInt128 Limit;
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}
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public int BatchSize
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{
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get => _batchSize;
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set => _batchSize = Math.Max(1, value);
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}
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public BigInteger MinK
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{
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get => _minK;
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set => _minK = value < BigInteger.One ? BigInteger.One : value;
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}
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public string? StateFilePath
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{
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get => _stateFilePath;
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set => _stateFilePath = value;
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}
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public void ResetStateTracking()
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{
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_stateCounter = 0;
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}
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public void ResumeFromState(BigInteger lastSavedK)
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{
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_lastSavedK = lastSavedK;
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_minK = lastSavedK + BigInteger.One;
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_stateCounter = 0;
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}
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public void ConfigureFromMaxPrime(ulong maxPrime)
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{
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_divisorLimit = ComputeDivisorLimitFromMaxPrimeBig(maxPrime);
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}
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public ulong DivisorLimit
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{
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[MethodImpl(MethodImplOptions.AggressiveInlining)]
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get
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{
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if (_divisorLimit.IsZero)
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{
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return ulong.MaxValue;
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}
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return _divisorLimit > ulong.MaxValue ? ulong.MaxValue : (ulong)_divisorLimit;
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}
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}
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[MethodImpl(MethodImplOptions.AggressiveInlining)]
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public ulong GetAllowedMaxDivisor(ulong prime) => ComputeAllowedMaxDivisor(prime, _divisorLimit);
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public bool IsPrime(PrimeOrderCalculatorAccelerator gpu, ulong prime, out bool divisorsExhausted, out BigInteger divisor)
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{
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BigInteger allowedMax = ComputeAllowedMaxDivisorBig(prime, _divisorLimit);
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// The CPU by-divisor run always hands us primes with enormous divisor limits, so the fallback below never executes.
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// if (allowedMax < 3UL)
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// {
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// // EvenPerfectBitScanner routes primes below the small-divisor cutoff to the GPU path, so the CPU path still sees
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// // trivial candidates during targeted tests. Short-circuit here to keep those runs aligned with the production flow.
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// divisorsExhausted = true;
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// return true;
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// }
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bool composite = CheckDivisors(
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gpu,
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prime,
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allowedMax,
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_minK,
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out bool processedAll,
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out divisor);
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if (composite)
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{
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divisorsExhausted = true;
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return false;
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}
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divisorsExhausted = processedAll || composite;
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divisor = BigInteger.Zero;
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return true;
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}
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public void PrepareCandidates(in ReadOnlySpan<ulong> primes, Span<ulong> allowedMaxValues)
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{
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ulong divisorLimit = GetAllowedDivisorLimitForSpan(_divisorLimit);
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int length = primes.Length;
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for (int index = 0; index < length; index++)
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{
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allowedMaxValues[index] = ComputeAllowedMaxDivisor(primes[index], divisorLimit);
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}
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}
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[MethodImpl(MethodImplOptions.AggressiveInlining | MethodImplOptions.AggressiveOptimization)]
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public IMersenneNumberDivisorByDivisorTester.IDivisorScanSession CreateDivisorSession(PrimeOrderCalculatorAccelerator gpu) => ThreadStaticPools.RentMersenneCpuDivisorSession(gpu, OrderDevice);
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private bool CheckDivisors(
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PrimeOrderCalculatorAccelerator gpu,
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ulong prime,
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BigInteger allowedMax,
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BigInteger minK,
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out bool processedAll,
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out BigInteger foundDivisor)
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{
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BigInteger normalizedMinK = minK < BigInteger.One ? BigInteger.One : minK;
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BigInteger step = ((BigInteger)prime) << 1;
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BigInteger firstDivisor = (step * normalizedMinK) + BigInteger.One;
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bool unlimited = allowedMax.IsZero;
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bool fits64 = normalizedMinK <= ulong.MaxValue && firstDivisor <= ulong.MaxValue;
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bool limitFits64 = unlimited || allowedMax <= ulong.MaxValue;
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if (fits64 && limitFits64)
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{
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ulong allowedMax64 = unlimited ? ulong.MaxValue : (ulong)allowedMax;
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||||
bool composite64 = CheckDivisors64Bit(
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gpu,
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prime,
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allowedMax64,
|
||||
(ulong)normalizedMinK,
|
||||
out processedAll,
|
||||
out ulong foundDivisor64);
|
||||
foundDivisor = foundDivisor64;
|
||||
return composite64;
|
||||
}
|
||||
|
||||
if (fits64 && allowedMax > ulong.MaxValue)
|
||||
{
|
||||
ulong allowedMax64 = ulong.MaxValue;
|
||||
bool composite64 = CheckDivisors64Bit(
|
||||
gpu,
|
||||
prime,
|
||||
allowedMax64,
|
||||
(ulong)normalizedMinK,
|
||||
out processedAll,
|
||||
out ulong foundDivisor64);
|
||||
if (composite64)
|
||||
{
|
||||
foundDivisor = foundDivisor64;
|
||||
return true;
|
||||
}
|
||||
|
||||
BigInteger iterations = ((BigInteger)(allowedMax64 - (ulong)firstDivisor) / (ulong)step) + BigInteger.One;
|
||||
BigInteger nextK = normalizedMinK + iterations;
|
||||
return CheckDivisorsLarge(
|
||||
gpu,
|
||||
prime,
|
||||
allowedMax,
|
||||
nextK,
|
||||
step,
|
||||
out processedAll,
|
||||
out foundDivisor);
|
||||
}
|
||||
|
||||
return CheckDivisorsLarge(
|
||||
gpu,
|
||||
prime,
|
||||
allowedMax,
|
||||
normalizedMinK,
|
||||
step,
|
||||
out processedAll,
|
||||
out foundDivisor);
|
||||
}
|
||||
|
||||
private bool CheckDivisors64Bit(
|
||||
PrimeOrderCalculatorAccelerator gpu,
|
||||
ulong prime,
|
||||
ulong allowedMax,
|
||||
ulong minK,
|
||||
out bool processedAll,
|
||||
out ulong foundDivisor)
|
||||
{
|
||||
foundDivisor = 0UL;
|
||||
processedAll = true;
|
||||
ulong currentK = minK < 1UL ? 1UL : minK;
|
||||
|
||||
// The EvenPerfectBitScanner feeds primes >= 138,000,000 here, so allowedMax >= 3 in production runs.
|
||||
// Keeping the guard commented out documents the reasoning for benchmarks and tests.
|
||||
// if (allowedMax < 3UL)
|
||||
// {
|
||||
// return false;
|
||||
// }
|
||||
|
||||
ref GpuUInt128WorkSet workSet = ref _divisorScanGpuWorkSet;
|
||||
|
||||
ref GpuUInt128 step = ref workSet.Step;
|
||||
step.High = 0UL;
|
||||
step.Low = prime;
|
||||
step.ShiftLeft(1);
|
||||
|
||||
ref GpuUInt128 limit = ref workSet.Limit;
|
||||
limit.High = 0UL;
|
||||
limit.Low = allowedMax;
|
||||
|
||||
ref GpuUInt128 divisor = ref workSet.Divisor;
|
||||
divisor.High = step.High;
|
||||
divisor.Low = step.Low;
|
||||
divisor.Add(1UL);
|
||||
if (minK > 1UL)
|
||||
{
|
||||
GpuUInt128 offset = new(minK - 1UL);
|
||||
divisor = step * offset;
|
||||
divisor.Add(1UL);
|
||||
}
|
||||
|
||||
if (divisor.CompareTo(limit) > 0)
|
||||
{
|
||||
processedAll = true;
|
||||
foundDivisor = 0UL;
|
||||
return false;
|
||||
}
|
||||
|
||||
// Intentionally recomputes factorizations without a per-thread cache.
|
||||
// The previous factor cache recorded virtually no hits and only slowed down the scan.
|
||||
|
||||
ulong stepHigh = step.High;
|
||||
ulong stepLow = step.Low;
|
||||
ulong limitHigh = limit.High;
|
||||
ulong divisorLow = divisor.Low;
|
||||
|
||||
if (stepHigh == 0UL && limitHigh == 0UL)
|
||||
{
|
||||
ulong maxK = allowedMax > 0UL ? (allowedMax - 1UL) / stepLow : 0UL;
|
||||
if (maxK == 0UL)
|
||||
{
|
||||
processedAll = true;
|
||||
foundDivisor = 0UL;
|
||||
return false;
|
||||
}
|
||||
|
||||
ulong startK = minK < 1UL ? 1UL : minK;
|
||||
bool processedTop = true;
|
||||
bool processedBottom = true;
|
||||
bool composite = false;
|
||||
|
||||
if (startK <= maxK)
|
||||
{
|
||||
composite = CheckDivisors64Range(
|
||||
gpu,
|
||||
prime,
|
||||
stepLow,
|
||||
allowedMax,
|
||||
startK,
|
||||
maxK,
|
||||
ref currentK,
|
||||
out processedTop,
|
||||
out foundDivisor);
|
||||
if (composite)
|
||||
{
|
||||
processedAll = true;
|
||||
return true;
|
||||
}
|
||||
}
|
||||
|
||||
ulong lowerEnd = startK > 1UL ? startK - 1UL : 0UL;
|
||||
if (lowerEnd >= 1UL && startK == 1UL)
|
||||
{
|
||||
lowerEnd = Math.Min(lowerEnd, maxK);
|
||||
currentK = 1UL;
|
||||
composite = CheckDivisors64Range(
|
||||
gpu,
|
||||
prime,
|
||||
stepLow,
|
||||
allowedMax,
|
||||
1UL,
|
||||
lowerEnd,
|
||||
ref currentK,
|
||||
out processedBottom,
|
||||
out foundDivisor);
|
||||
}
|
||||
|
||||
processedAll = processedTop && processedBottom;
|
||||
return composite;
|
||||
}
|
||||
|
||||
ulong divisorHigh = divisor.High;
|
||||
var residueStepper = new MersenneDivisorResidueStepper(prime, step, divisor);
|
||||
|
||||
while (divisor.CompareTo(limit) <= 0)
|
||||
{
|
||||
if (residueStepper.IsAdmissible())
|
||||
{
|
||||
ulong candidate = divisor.Low;
|
||||
MontgomeryDivisorData divisorData = MontgomeryDivisorData.FromModulus(candidate);
|
||||
ulong divisorCycle;
|
||||
// Divisors generated from 2 * k * p + 1 exceed the small-cycle snapshot when p >= 138,000,000, so the short path below never runs.
|
||||
if (!_tryCalculateCycleLengthForExponent(
|
||||
candidate,
|
||||
gpu,
|
||||
prime,
|
||||
divisorData,
|
||||
out ulong computedCycle,
|
||||
out bool primeOrderFailed) || computedCycle == 0UL)
|
||||
{
|
||||
// Divisors produced by 2 * k * p + 1 always exceed PerfectNumberConstants.MaxQForDivisorCycles
|
||||
// for the exponents scanned here, so skip the unused cache fallback and compute directly.
|
||||
divisorCycle = _calculateCycleLength(
|
||||
candidate,
|
||||
gpu,
|
||||
divisorData,
|
||||
skipPrimeOrderHeuristic: primeOrderFailed);
|
||||
}
|
||||
else
|
||||
{
|
||||
divisorCycle = computedCycle;
|
||||
}
|
||||
|
||||
RecordState(currentK);
|
||||
if (divisorCycle == prime)
|
||||
{
|
||||
// A cycle equal to the tested exponent (which is prime in this path) guarantees that the candidate divides
|
||||
// the corresponding Mersenne number because the order of 2 modulo the divisor is exactly p.
|
||||
foundDivisor = candidate;
|
||||
processedAll = true;
|
||||
return true;
|
||||
}
|
||||
|
||||
if (divisorCycle == 0UL)
|
||||
{
|
||||
Console.WriteLine($"Divisor cycle was not calculated for {prime}");
|
||||
}
|
||||
}
|
||||
|
||||
divisor.Add(step);
|
||||
currentK++;
|
||||
residueStepper.Advance();
|
||||
}
|
||||
|
||||
processedAll = true;
|
||||
foundDivisor = 0UL;
|
||||
return false;
|
||||
}
|
||||
|
||||
private bool CheckDivisorsLarge(
|
||||
PrimeOrderCalculatorAccelerator gpu,
|
||||
ulong prime,
|
||||
BigInteger allowedMax,
|
||||
BigInteger minK,
|
||||
BigInteger step,
|
||||
out bool processedAll,
|
||||
out BigInteger foundDivisor)
|
||||
{
|
||||
processedAll = true;
|
||||
foundDivisor = BigInteger.Zero;
|
||||
BigInteger currentK = minK < BigInteger.One ? BigInteger.One : minK;
|
||||
BigInteger divisor = (step * currentK) + BigInteger.One;
|
||||
_ = gpu;
|
||||
if (allowedMax.IsZero)
|
||||
{
|
||||
processedAll = false;
|
||||
return false;
|
||||
}
|
||||
if (divisor > allowedMax)
|
||||
{
|
||||
return false;
|
||||
}
|
||||
|
||||
LastDigit lastDigit = (prime & 3UL) == 3UL ? LastDigit.Seven : LastDigit.One;
|
||||
ushort decimalMask = DivisorGenerator.GetDecimalMask(lastDigit);
|
||||
|
||||
var rem10 = new BigIntegerCycleRemainderStepper(10);
|
||||
var rem8 = new BigIntegerCycleRemainderStepper(8);
|
||||
var rem5 = new BigIntegerCycleRemainderStepper(5);
|
||||
var rem3 = new BigIntegerCycleRemainderStepper(3);
|
||||
var rem7 = new BigIntegerCycleRemainderStepper(7);
|
||||
var rem11 = new BigIntegerCycleRemainderStepper(11);
|
||||
var rem13 = new BigIntegerCycleRemainderStepper(13);
|
||||
var rem17 = new BigIntegerCycleRemainderStepper(17);
|
||||
var rem19 = new BigIntegerCycleRemainderStepper(19);
|
||||
|
||||
byte remainder10 = (byte)rem10.Initialize(divisor);
|
||||
byte remainder8 = (byte)rem8.Initialize(divisor);
|
||||
byte remainder5 = (byte)rem5.Initialize(divisor);
|
||||
byte remainder3 = (byte)rem3.Initialize(divisor);
|
||||
byte remainder7 = (byte)rem7.Initialize(divisor);
|
||||
byte remainder11 = (byte)rem11.Initialize(divisor);
|
||||
byte remainder13 = (byte)rem13.Initialize(divisor);
|
||||
byte remainder17 = (byte)rem17.Initialize(divisor);
|
||||
byte remainder19 = (byte)rem19.Initialize(divisor);
|
||||
|
||||
while (divisor <= allowedMax)
|
||||
{
|
||||
bool passesSmallModuli = remainder3 != 0 && remainder5 != 0 && remainder7 != 0 && remainder11 != 0 && remainder13 != 0 && remainder17 != 0 && remainder19 != 0;
|
||||
if (passesSmallModuli && (remainder8 == 1 || remainder8 == 7) && ((decimalMask >> remainder10) & 1) != 0)
|
||||
{
|
||||
if (IsProbablePrimeBigInteger(divisor))
|
||||
{
|
||||
BigInteger powResult = BigInteger.ModPow(2, prime, divisor);
|
||||
RecordState(currentK);
|
||||
if (powResult.IsOne)
|
||||
{
|
||||
foundDivisor = divisor;
|
||||
processedAll = true;
|
||||
return true;
|
||||
}
|
||||
}
|
||||
else
|
||||
{
|
||||
RecordState(currentK);
|
||||
}
|
||||
}
|
||||
|
||||
currentK += BigInteger.One;
|
||||
divisor += step;
|
||||
remainder10 = (byte)rem10.ComputeNext(divisor);
|
||||
remainder8 = (byte)rem8.ComputeNext(divisor);
|
||||
remainder5 = (byte)rem5.ComputeNext(divisor);
|
||||
remainder3 = (byte)rem3.ComputeNext(divisor);
|
||||
remainder7 = (byte)rem7.ComputeNext(divisor);
|
||||
remainder11 = (byte)rem11.ComputeNext(divisor);
|
||||
remainder13 = (byte)rem13.ComputeNext(divisor);
|
||||
remainder17 = (byte)rem17.ComputeNext(divisor);
|
||||
remainder19 = (byte)rem19.ComputeNext(divisor);
|
||||
|
||||
if (divisor > allowedMax)
|
||||
{
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
processedAll = true;
|
||||
foundDivisor = BigInteger.Zero;
|
||||
return false;
|
||||
}
|
||||
|
||||
private bool CheckDivisors64Range(
|
||||
PrimeOrderCalculatorAccelerator gpu,
|
||||
ulong prime,
|
||||
ulong step,
|
||||
ulong allowedMax,
|
||||
ulong startK,
|
||||
ulong endK,
|
||||
ref ulong currentK,
|
||||
out bool processedAll,
|
||||
out ulong foundDivisor)
|
||||
{
|
||||
if (startK < 1UL || endK < startK)
|
||||
{
|
||||
processedAll = true;
|
||||
foundDivisor = 0UL;
|
||||
return false;
|
||||
}
|
||||
currentK = startK;
|
||||
|
||||
UInt128 step128 = step;
|
||||
UInt128 allowedMax128 = allowedMax;
|
||||
UInt128 startDivisor128 = (step128 * startK) + UInt128.One;
|
||||
if (startDivisor128 > allowedMax128)
|
||||
{
|
||||
processedAll = true;
|
||||
foundDivisor = 0UL;
|
||||
return false;
|
||||
}
|
||||
|
||||
UInt128 rangeLimit128 = (step128 * endK) + UInt128.One;
|
||||
if (rangeLimit128 > allowedMax128)
|
||||
{
|
||||
rangeLimit128 = allowedMax128;
|
||||
}
|
||||
|
||||
ulong startDivisor = (ulong)startDivisor128;
|
||||
ulong rangeLimit = (ulong)rangeLimit128;
|
||||
|
||||
var residueStepper = new MersenneDivisorResidueStepper(prime, (GpuUInt128)step128, (GpuUInt128)startDivisor128);
|
||||
|
||||
return CheckDivisors64(
|
||||
gpu,
|
||||
prime,
|
||||
step,
|
||||
rangeLimit,
|
||||
startDivisor,
|
||||
ref residueStepper,
|
||||
ref currentK,
|
||||
out processedAll,
|
||||
out foundDivisor);
|
||||
}
|
||||
|
||||
private bool CheckDivisors64(
|
||||
PrimeOrderCalculatorAccelerator gpu,
|
||||
ulong prime,
|
||||
ulong step,
|
||||
ulong limit,
|
||||
ulong divisor,
|
||||
ref MersenneDivisorResidueStepper residueStepper,
|
||||
ref ulong currentK,
|
||||
out bool processedAll,
|
||||
out ulong foundDivisor)
|
||||
{
|
||||
bool canAdvance = step <= limit;
|
||||
if (!canAdvance)
|
||||
{
|
||||
if (divisor <= limit && residueStepper.IsAdmissible())
|
||||
{
|
||||
MontgomeryDivisorData divisorData = MontgomeryDivisorData.FromModulus(divisor);
|
||||
ulong divisorCycle;
|
||||
if (!_tryCalculateCycleLengthForExponent(
|
||||
divisor,
|
||||
gpu,
|
||||
prime,
|
||||
divisorData,
|
||||
out ulong computedCycle,
|
||||
out bool primeOrderFailed) || computedCycle == 0UL)
|
||||
{
|
||||
divisorCycle = _calculateCycleLength(
|
||||
divisor,
|
||||
gpu,
|
||||
divisorData,
|
||||
skipPrimeOrderHeuristic: primeOrderFailed);
|
||||
}
|
||||
else
|
||||
{
|
||||
divisorCycle = computedCycle;
|
||||
}
|
||||
|
||||
if (divisorCycle == prime)
|
||||
{
|
||||
foundDivisor = divisor;
|
||||
processedAll = true;
|
||||
return true;
|
||||
}
|
||||
|
||||
if (divisorCycle == 0UL)
|
||||
{
|
||||
Console.WriteLine($"Divisor cycle was not calculated for {prime}");
|
||||
}
|
||||
}
|
||||
|
||||
processedAll = true;
|
||||
foundDivisor = 0UL;
|
||||
return false;
|
||||
}
|
||||
|
||||
if (divisor > limit)
|
||||
{
|
||||
processedAll = true;
|
||||
foundDivisor = 0UL;
|
||||
return false;
|
||||
}
|
||||
|
||||
ulong remainingIterations = ((limit - divisor) / step) + 1UL;
|
||||
while (true)
|
||||
{
|
||||
if (residueStepper.IsAdmissible())
|
||||
{
|
||||
MontgomeryDivisorData divisorData = MontgomeryDivisorData.FromModulus(divisor);
|
||||
ulong divisorCycle;
|
||||
if (!_tryCalculateCycleLengthForExponent(
|
||||
divisor,
|
||||
gpu,
|
||||
prime,
|
||||
divisorData,
|
||||
out ulong computedCycle,
|
||||
out bool primeOrderFailed) || computedCycle == 0UL)
|
||||
{
|
||||
divisorCycle = _calculateCycleLength(
|
||||
divisor,
|
||||
gpu,
|
||||
divisorData,
|
||||
skipPrimeOrderHeuristic: primeOrderFailed);
|
||||
}
|
||||
else
|
||||
{
|
||||
divisorCycle = computedCycle;
|
||||
}
|
||||
|
||||
RecordState(currentK);
|
||||
if (divisorCycle == prime)
|
||||
{
|
||||
foundDivisor = divisor;
|
||||
processedAll = true;
|
||||
return true;
|
||||
}
|
||||
|
||||
if (divisorCycle == 0UL)
|
||||
{
|
||||
Console.WriteLine($"Divisor cycle was not calculated for {prime}");
|
||||
}
|
||||
}
|
||||
|
||||
remainingIterations--;
|
||||
if (remainingIterations == 0UL)
|
||||
{
|
||||
processedAll = true;
|
||||
foundDivisor = 0UL;
|
||||
return false;
|
||||
}
|
||||
|
||||
divisor += step;
|
||||
currentK++;
|
||||
residueStepper.Advance();
|
||||
}
|
||||
}
|
||||
|
||||
private static byte CheckDivisor(ulong prime, ulong divisorCycle, in MontgomeryDivisorData divisorData)
|
||||
{
|
||||
ulong residue = prime.Pow2MontgomeryModWithCycleConvertToStandardCpu(divisorCycle, divisorData);
|
||||
return residue == 1UL ? (byte)1 : (byte)0;
|
||||
}
|
||||
|
||||
private void RecordState(BigInteger k)
|
||||
{
|
||||
string? path = _stateFilePath;
|
||||
if (string.IsNullOrEmpty(path))
|
||||
{
|
||||
return;
|
||||
}
|
||||
|
||||
if (k <= _lastSavedK)
|
||||
{
|
||||
return;
|
||||
}
|
||||
|
||||
int next = _stateCounter + 1;
|
||||
if (next >= PerfectNumberConstants.ByDivisorStateSaveInterval)
|
||||
{
|
||||
string? directory = Path.GetDirectoryName(path);
|
||||
if (!string.IsNullOrEmpty(directory))
|
||||
{
|
||||
Directory.CreateDirectory(directory);
|
||||
}
|
||||
|
||||
File.AppendAllText(path, k.ToString(CultureInfo.InvariantCulture) + Environment.NewLine);
|
||||
_stateCounter = 0;
|
||||
_lastSavedK = k;
|
||||
}
|
||||
else
|
||||
{
|
||||
_stateCounter = next;
|
||||
}
|
||||
}
|
||||
|
||||
private static bool IsProbablePrimeBigInteger(BigInteger value)
|
||||
{
|
||||
if (value <= 3)
|
||||
{
|
||||
return value >= 2;
|
||||
}
|
||||
|
||||
if (value.IsEven)
|
||||
{
|
||||
return false;
|
||||
}
|
||||
|
||||
BigInteger d = value - 1;
|
||||
int s = 0;
|
||||
while ((d & 1) == 0)
|
||||
{
|
||||
d >>= 1;
|
||||
s++;
|
||||
}
|
||||
|
||||
ReadOnlySpan<int> bases = stackalloc int[] { 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37 };
|
||||
for (int i = 0; i < bases.Length; i++)
|
||||
{
|
||||
int baseValue = bases[i];
|
||||
if ((BigInteger)baseValue >= value)
|
||||
{
|
||||
continue;
|
||||
}
|
||||
|
||||
var expStepper = new BigIntegerExponentStepper(value, baseValue);
|
||||
BigInteger x = expStepper.Initialize(d);
|
||||
if (x == 1 || x == value - 1)
|
||||
{
|
||||
continue;
|
||||
}
|
||||
|
||||
bool witnessFound = true;
|
||||
for (int r = 1; r < s; r++)
|
||||
{
|
||||
BigInteger targetExponent = d << r;
|
||||
x = expStepper.ComputeNext(targetExponent);
|
||||
if (x == value - 1)
|
||||
{
|
||||
witnessFound = false;
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
if (witnessFound)
|
||||
{
|
||||
return false;
|
||||
}
|
||||
}
|
||||
|
||||
return true;
|
||||
}
|
||||
|
||||
private static bool TryCalculateCycleLengthForExponentCpu(
|
||||
ulong divisor,
|
||||
PrimeOrderCalculatorAccelerator gpu,
|
||||
ulong exponent,
|
||||
in MontgomeryDivisorData divisorData,
|
||||
out ulong cycleLength,
|
||||
out bool primeOrderFailed) => MersenneDivisorCycles.TryCalculateCycleLengthForExponentCpu(
|
||||
divisor,
|
||||
exponent,
|
||||
divisorData,
|
||||
out cycleLength,
|
||||
out primeOrderFailed);
|
||||
|
||||
private static bool TryCalculateCycleLengthForExponentHybrid(
|
||||
ulong divisor,
|
||||
PrimeOrderCalculatorAccelerator gpu,
|
||||
ulong exponent,
|
||||
in MontgomeryDivisorData divisorData,
|
||||
out ulong cycleLength,
|
||||
out bool primeOrderFailed) => MersenneDivisorCycles.TryCalculateCycleLengthForExponentHybrid(
|
||||
gpu,
|
||||
divisor,
|
||||
exponent,
|
||||
divisorData,
|
||||
out cycleLength,
|
||||
out primeOrderFailed);
|
||||
|
||||
private static bool TryCalculateCycleLengthForExponentGpu(
|
||||
ulong divisor,
|
||||
PrimeOrderCalculatorAccelerator gpu,
|
||||
ulong exponent,
|
||||
in MontgomeryDivisorData divisorData,
|
||||
out ulong cycleLength,
|
||||
out bool primeOrderFailed) => MersenneDivisorCycles.TryCalculateCycleLengthForExponentGpu(
|
||||
gpu,
|
||||
divisor,
|
||||
exponent,
|
||||
divisorData,
|
||||
out cycleLength,
|
||||
out primeOrderFailed);
|
||||
|
||||
private static ulong CalculateCycleLengthCpu(
|
||||
ulong divisor,
|
||||
PrimeOrderCalculatorAccelerator gpu,
|
||||
in MontgomeryDivisorData divisorData,
|
||||
bool skipPrimeOrderHeuristic) => MersenneDivisorCycles.CalculateCycleLengthCpu(
|
||||
divisor,
|
||||
divisorData,
|
||||
skipPrimeOrderHeuristic);
|
||||
|
||||
private static ulong CalculateCycleLengthHybrid(
|
||||
ulong divisor,
|
||||
PrimeOrderCalculatorAccelerator gpu,
|
||||
in MontgomeryDivisorData divisorData,
|
||||
bool skipPrimeOrderHeuristic) => MersenneDivisorCycles.CalculateCycleLengthHybrid(
|
||||
gpu,
|
||||
divisor,
|
||||
divisorData,
|
||||
skipPrimeOrderHeuristic);
|
||||
|
||||
private static ulong CalculateCycleLengthGpu(
|
||||
ulong divisor,
|
||||
PrimeOrderCalculatorAccelerator gpu,
|
||||
in MontgomeryDivisorData divisorData,
|
||||
bool skipPrimeOrderHeuristic) => MersenneDivisorCycles.CalculateCycleLengthGpu(
|
||||
gpu,
|
||||
divisor,
|
||||
divisorData,
|
||||
skipPrimeOrderHeuristic);
|
||||
|
||||
[MethodImpl(MethodImplOptions.AggressiveInlining)]
|
||||
private static byte AddMod3(byte value, byte delta)
|
||||
{
|
||||
const int Modulus = 3;
|
||||
int sum = value + delta;
|
||||
|
||||
if (sum >= Modulus)
|
||||
{
|
||||
sum -= Modulus;
|
||||
}
|
||||
|
||||
return (byte)sum;
|
||||
}
|
||||
|
||||
|
||||
[MethodImpl(MethodImplOptions.AggressiveInlining)]
|
||||
private static byte AddMod7(byte value, byte delta)
|
||||
{
|
||||
const int Modulus = 7;
|
||||
int sum = value + delta;
|
||||
|
||||
if (sum >= Modulus)
|
||||
{
|
||||
sum -= Modulus;
|
||||
}
|
||||
|
||||
return (byte)sum;
|
||||
}
|
||||
|
||||
[MethodImpl(MethodImplOptions.AggressiveInlining)]
|
||||
private static byte AddMod13(byte value, byte delta)
|
||||
{
|
||||
const int Modulus = 13;
|
||||
int sum = value + delta;
|
||||
|
||||
if (sum >= Modulus)
|
||||
{
|
||||
sum -= Modulus;
|
||||
}
|
||||
|
||||
return (byte)sum;
|
||||
}
|
||||
|
||||
[MethodImpl(MethodImplOptions.AggressiveInlining)]
|
||||
private static byte AddMod17(byte value, byte delta)
|
||||
{
|
||||
const int Modulus = 17;
|
||||
int sum = value + delta;
|
||||
|
||||
if (sum >= Modulus)
|
||||
{
|
||||
sum -= Modulus;
|
||||
}
|
||||
|
||||
return (byte)sum;
|
||||
}
|
||||
|
||||
[MethodImpl(MethodImplOptions.AggressiveInlining)]
|
||||
private static byte AddMod19(byte value, byte delta)
|
||||
{
|
||||
const int Modulus = 19;
|
||||
int sum = value + delta;
|
||||
|
||||
if (sum >= Modulus)
|
||||
{
|
||||
sum -= Modulus;
|
||||
}
|
||||
|
||||
return (byte)sum;
|
||||
}
|
||||
|
||||
[MethodImpl(MethodImplOptions.AggressiveInlining)]
|
||||
private static byte AddMod10(byte value, byte delta)
|
||||
{
|
||||
const int Modulus = 10;
|
||||
int sum = value + delta;
|
||||
|
||||
if (sum >= Modulus)
|
||||
{
|
||||
sum -= Modulus;
|
||||
}
|
||||
|
||||
return (byte)sum;
|
||||
}
|
||||
|
||||
[MethodImpl(MethodImplOptions.AggressiveInlining)]
|
||||
private static byte AddMod11(byte value, byte delta)
|
||||
{
|
||||
const int Modulus = 11;
|
||||
int sum = value + delta;
|
||||
|
||||
if (sum >= Modulus)
|
||||
{
|
||||
sum -= Modulus;
|
||||
}
|
||||
|
||||
return (byte)sum;
|
||||
}
|
||||
|
||||
[MethodImpl(MethodImplOptions.AggressiveInlining)]
|
||||
private static byte AddMod8(byte value, byte delta)
|
||||
{
|
||||
return (byte)((value + delta) & 7);
|
||||
}
|
||||
|
||||
[MethodImpl(MethodImplOptions.AggressiveInlining)]
|
||||
private static ulong GetAllowedDivisorLimitForSpan(BigInteger divisorLimit)
|
||||
{
|
||||
if (divisorLimit.IsZero)
|
||||
{
|
||||
return ulong.MaxValue;
|
||||
}
|
||||
|
||||
return divisorLimit > ulong.MaxValue ? ulong.MaxValue : (ulong)divisorLimit;
|
||||
}
|
||||
|
||||
private static BigInteger ComputeDivisorLimitFromMaxPrimeBig(ulong maxPrime)
|
||||
{
|
||||
if (maxPrime <= 1UL)
|
||||
{
|
||||
return BigInteger.Zero;
|
||||
}
|
||||
|
||||
if (maxPrime - 1UL >= 64UL)
|
||||
{
|
||||
return (BigInteger.One << 256) - BigInteger.One;
|
||||
}
|
||||
|
||||
return (BigInteger.One << (int)(maxPrime - 1UL)) - BigInteger.One;
|
||||
}
|
||||
|
||||
private static BigInteger ComputeAllowedMaxDivisorBig(ulong prime, BigInteger divisorLimit)
|
||||
{
|
||||
if (prime <= 1UL)
|
||||
{
|
||||
return BigInteger.Zero;
|
||||
}
|
||||
|
||||
if (divisorLimit.IsZero || prime - 1UL >= 64UL)
|
||||
{
|
||||
return divisorLimit;
|
||||
}
|
||||
|
||||
BigInteger candidateLimit = (BigInteger.One << (int)(prime - 1UL)) - BigInteger.One;
|
||||
if (divisorLimit.IsZero)
|
||||
{
|
||||
return candidateLimit;
|
||||
}
|
||||
|
||||
return BigInteger.Min(candidateLimit, divisorLimit);
|
||||
}
|
||||
|
||||
private static ulong ComputeAllowedMaxDivisor(ulong prime, BigInteger divisorLimit)
|
||||
{
|
||||
BigInteger allowed = ComputeAllowedMaxDivisorBig(prime, divisorLimit);
|
||||
if (allowed.IsZero)
|
||||
{
|
||||
return ulong.MaxValue;
|
||||
}
|
||||
|
||||
return allowed > ulong.MaxValue ? ulong.MaxValue : (ulong)allowed;
|
||||
}
|
||||
|
||||
|
||||
}
|
||||
@@ -0,0 +1,585 @@
|
||||
using System.Numerics;
|
||||
using System.Runtime.CompilerServices;
|
||||
using System.Globalization;
|
||||
using PerfectNumbers.Core.Gpu;
|
||||
using PerfectNumbers.Core.Gpu.Accelerators;
|
||||
|
||||
namespace PerfectNumbers.Core.Cpu;
|
||||
|
||||
public struct MersenneNumberDivisorByDivisorCpuTesterWithCpuOrder() : IMersenneNumberDivisorByDivisorTester
|
||||
{
|
||||
public BigInteger DivisorLimit;
|
||||
public BigInteger MinK = EnvironmentConfiguration.MinK;
|
||||
|
||||
#pragma warning disable CS8618 // StateFilePath is always set on EvenPerfectBitScanner execution path when ResumeFromState is called.
|
||||
private string StateFilePath;
|
||||
#pragma warning restore CS8618 // Non-nullable field must contain a non-null value when exiting constructor. Consider adding the 'required' modifier or declaring as nullable.
|
||||
|
||||
private int _stateCounter;
|
||||
private BigInteger _lastSavedK;
|
||||
|
||||
private GpuUInt128WorkSet _divisorScanGpuWorkSet;
|
||||
|
||||
[MethodImpl(MethodImplOptions.AggressiveInlining | MethodImplOptions.AggressiveOptimization)]
|
||||
public void ResetStateTracking()
|
||||
{
|
||||
_stateCounter = 0;
|
||||
}
|
||||
|
||||
[MethodImpl(MethodImplOptions.AggressiveInlining | MethodImplOptions.AggressiveOptimization)]
|
||||
public void ResumeFromState(in string stateFile, in BigInteger lastSavedK, in BigInteger minK)
|
||||
{
|
||||
StateFilePath = stateFile;
|
||||
_lastSavedK = lastSavedK;
|
||||
MinK = minK;
|
||||
_stateCounter = 0;
|
||||
}
|
||||
|
||||
public bool IsPrime(ulong prime, out bool divisorsExhausted, out BigInteger divisor)
|
||||
{
|
||||
BigInteger allowedMax = MersenneNumberDivisorByDivisorTester.ComputeAllowedMaxDivisorBig(prime, DivisorLimit);
|
||||
|
||||
// The CPU by-divisor run always hands us primes with enormous divisor limits, so the fallback below never executes.
|
||||
// if (allowedMax < 3UL)
|
||||
// {
|
||||
// // EvenPerfectBitScanner routes primes below the small-divisor cutoff to the GPU path, so the CPU path still sees
|
||||
// // trivial candidates during targeted tests. Short-circuit here to keep those runs aligned with the production flow.
|
||||
// divisorsExhausted = true;
|
||||
// return true;
|
||||
// }
|
||||
|
||||
|
||||
bool composite = CheckDivisors(
|
||||
prime,
|
||||
allowedMax,
|
||||
MinK,
|
||||
out bool processedAll,
|
||||
out divisor);
|
||||
|
||||
if (composite)
|
||||
{
|
||||
divisorsExhausted = true;
|
||||
return false;
|
||||
}
|
||||
|
||||
divisorsExhausted = processedAll || composite;
|
||||
divisor = BigInteger.Zero;
|
||||
return true;
|
||||
}
|
||||
|
||||
public void PrepareCandidates(ulong maxPrime, in ReadOnlySpan<ulong> primes, Span<ulong> allowedMaxValues)
|
||||
{
|
||||
BigInteger divisorLimitBigInteger = MersenneNumberDivisorByDivisorTester.ComputeDivisorLimitFromMaxPrimeBig(maxPrime);
|
||||
DivisorLimit = divisorLimitBigInteger;
|
||||
ulong divisorLimit = MersenneNumberDivisorByDivisorTester.GetAllowedDivisorLimitForSpan(divisorLimitBigInteger);
|
||||
int length = primes.Length;
|
||||
for (int index = 0; index < length; index++)
|
||||
{
|
||||
allowedMaxValues[index] = MersenneNumberDivisorByDivisorTester.ComputeAllowedMaxDivisor(primes[index], divisorLimit);
|
||||
}
|
||||
}
|
||||
|
||||
[MethodImpl(MethodImplOptions.AggressiveInlining | MethodImplOptions.AggressiveOptimization)]
|
||||
public readonly IMersenneNumberDivisorByDivisorTester.IDivisorScanSession CreateDivisorSession(PrimeOrderCalculatorAccelerator gpu) => new MersenneCpuDivisorScanSessionWithCpuOrder();
|
||||
|
||||
private bool CheckDivisors(
|
||||
ulong prime,
|
||||
BigInteger allowedMax,
|
||||
BigInteger minK,
|
||||
out bool processedAll,
|
||||
out BigInteger foundDivisor)
|
||||
{
|
||||
BigInteger normalizedMinK = minK < BigInteger.One ? BigInteger.One : minK;
|
||||
BigInteger step = ((BigInteger)prime) << 1;
|
||||
BigInteger firstDivisor = (step * normalizedMinK) + BigInteger.One;
|
||||
bool unlimited = allowedMax.IsZero;
|
||||
|
||||
bool fits64 = normalizedMinK <= ulong.MaxValue && firstDivisor <= ulong.MaxValue;
|
||||
bool limitFits64 = unlimited || allowedMax <= ulong.MaxValue;
|
||||
if (fits64 && limitFits64)
|
||||
{
|
||||
ulong allowedMax64 = unlimited ? ulong.MaxValue : (ulong)allowedMax;
|
||||
bool composite64 = CheckDivisors64Bit(
|
||||
prime,
|
||||
allowedMax64,
|
||||
(ulong)normalizedMinK,
|
||||
out processedAll,
|
||||
out ulong foundDivisor64);
|
||||
foundDivisor = foundDivisor64;
|
||||
return composite64;
|
||||
}
|
||||
|
||||
if (fits64 && allowedMax > ulong.MaxValue)
|
||||
{
|
||||
ulong allowedMax64 = ulong.MaxValue;
|
||||
bool composite64 = CheckDivisors64Bit(
|
||||
prime,
|
||||
allowedMax64,
|
||||
(ulong)normalizedMinK,
|
||||
out processedAll,
|
||||
out ulong foundDivisor64);
|
||||
if (composite64)
|
||||
{
|
||||
foundDivisor = foundDivisor64;
|
||||
return true;
|
||||
}
|
||||
|
||||
BigInteger iterations = ((BigInteger)(allowedMax64 - (ulong)firstDivisor) / (ulong)step) + BigInteger.One;
|
||||
BigInteger nextK = normalizedMinK + iterations;
|
||||
return CheckDivisorsLarge(
|
||||
prime,
|
||||
allowedMax,
|
||||
nextK,
|
||||
step,
|
||||
out processedAll,
|
||||
out foundDivisor);
|
||||
}
|
||||
|
||||
return CheckDivisorsLarge(
|
||||
prime,
|
||||
allowedMax,
|
||||
normalizedMinK,
|
||||
step,
|
||||
out processedAll,
|
||||
out foundDivisor);
|
||||
}
|
||||
|
||||
private bool CheckDivisors64Bit(
|
||||
ulong prime,
|
||||
ulong allowedMax,
|
||||
ulong minK,
|
||||
out bool processedAll,
|
||||
out ulong foundDivisor)
|
||||
{
|
||||
foundDivisor = 0UL;
|
||||
ulong currentK = minK < 1UL ? 1UL : minK;
|
||||
|
||||
// The EvenPerfectBitScanner feeds primes >= 138,000,000 here, so allowedMax >= 3 in production runs.
|
||||
// Keeping the guard commented out documents the reasoning for benchmarks and tests.
|
||||
// if (allowedMax < 3UL)
|
||||
// {
|
||||
// return false;
|
||||
// }
|
||||
|
||||
ref GpuUInt128WorkSet workSet = ref _divisorScanGpuWorkSet;
|
||||
|
||||
ref GpuUInt128 step = ref workSet.Step;
|
||||
step.High = 0UL;
|
||||
step.Low = prime;
|
||||
step.ShiftLeft(1);
|
||||
|
||||
ref GpuUInt128 limit = ref workSet.Limit;
|
||||
limit.High = 0UL;
|
||||
limit.Low = allowedMax;
|
||||
|
||||
ref GpuUInt128 divisor = ref workSet.Divisor;
|
||||
divisor.High = step.High;
|
||||
divisor.Low = step.Low;
|
||||
divisor.Add(1UL);
|
||||
if (minK > 1UL)
|
||||
{
|
||||
GpuUInt128 offset = new(minK - 1UL);
|
||||
divisor = step * offset;
|
||||
divisor.Add(1UL);
|
||||
}
|
||||
|
||||
if (divisor.CompareTo(limit) > 0)
|
||||
{
|
||||
processedAll = true;
|
||||
foundDivisor = 0UL;
|
||||
return false;
|
||||
}
|
||||
|
||||
// Intentionally recomputes factorizations without a per-thread cache.
|
||||
// The previous factor cache recorded virtually no hits and only slowed down the scan.
|
||||
|
||||
ulong stepHigh = step.High;
|
||||
ulong stepLow = step.Low;
|
||||
ulong limitHigh = limit.High;
|
||||
|
||||
if (stepHigh == 0UL && limitHigh == 0UL)
|
||||
{
|
||||
ulong maxK = allowedMax > 0UL ? (allowedMax - 1UL) / stepLow : 0UL;
|
||||
if (maxK == 0UL)
|
||||
{
|
||||
processedAll = true;
|
||||
foundDivisor = 0UL;
|
||||
return false;
|
||||
}
|
||||
|
||||
ulong startK = minK < 1UL ? 1UL : minK;
|
||||
bool processedTop = true;
|
||||
bool processedBottom = true;
|
||||
bool composite = false;
|
||||
|
||||
if (startK <= maxK)
|
||||
{
|
||||
composite = CheckDivisors64Range(
|
||||
prime,
|
||||
stepLow,
|
||||
allowedMax,
|
||||
startK,
|
||||
maxK,
|
||||
ref currentK,
|
||||
out processedTop,
|
||||
out foundDivisor);
|
||||
if (composite)
|
||||
{
|
||||
processedAll = true;
|
||||
return true;
|
||||
}
|
||||
}
|
||||
|
||||
ulong lowerEnd = startK > 1UL ? startK - 1UL : 0UL;
|
||||
if (lowerEnd >= 1UL && startK == 1UL)
|
||||
{
|
||||
lowerEnd = Math.Min(lowerEnd, maxK);
|
||||
currentK = 1UL;
|
||||
composite = CheckDivisors64Range(
|
||||
prime,
|
||||
stepLow,
|
||||
allowedMax,
|
||||
1UL,
|
||||
lowerEnd,
|
||||
ref currentK,
|
||||
out processedBottom,
|
||||
out foundDivisor);
|
||||
}
|
||||
|
||||
processedAll = processedTop && processedBottom;
|
||||
return composite;
|
||||
}
|
||||
|
||||
var residueStepper = new MersenneDivisorResidueStepper(prime, step, divisor);
|
||||
|
||||
while (divisor.CompareTo(limit) <= 0)
|
||||
{
|
||||
if (residueStepper.IsAdmissible())
|
||||
{
|
||||
ulong candidate = divisor.Low;
|
||||
MontgomeryDivisorData divisorData = MontgomeryDivisorData.FromModulus(candidate);
|
||||
ulong divisorCycle;
|
||||
// Divisors generated from 2 * k * p + 1 exceed the small-cycle snapshot when p >= 138,000,000, so the short path below never runs.
|
||||
if (!MersenneNumberDivisorByDivisorTester.TryCalculateCycleLengthForExponentCpu(
|
||||
candidate,
|
||||
prime,
|
||||
divisorData,
|
||||
out ulong computedCycle,
|
||||
out bool primeOrderFailed) || computedCycle == 0UL)
|
||||
{
|
||||
// Divisors produced by 2 * k * p + 1 always exceed PerfectNumberConstants.MaxQForDivisorCycles
|
||||
// for the exponents scanned here, so skip the unused cache fallback and compute directly.
|
||||
divisorCycle = MersenneNumberDivisorByDivisorTester.CalculateCycleLengthCpu(
|
||||
candidate,
|
||||
divisorData,
|
||||
skipPrimeOrderHeuristic: primeOrderFailed);
|
||||
}
|
||||
else
|
||||
{
|
||||
divisorCycle = computedCycle;
|
||||
}
|
||||
|
||||
RecordState(StateFilePath, currentK);
|
||||
if (divisorCycle == prime)
|
||||
{
|
||||
// A cycle equal to the tested exponent (which is prime in this path) guarantees that the candidate divides
|
||||
// the corresponding Mersenne number because the order of 2 modulo the divisor is exactly p.
|
||||
foundDivisor = candidate;
|
||||
processedAll = true;
|
||||
return true;
|
||||
}
|
||||
|
||||
if (divisorCycle == 0UL)
|
||||
{
|
||||
Console.WriteLine($"Divisor cycle was not calculated for {prime}");
|
||||
}
|
||||
}
|
||||
|
||||
divisor.Add(step);
|
||||
currentK++;
|
||||
residueStepper.Advance();
|
||||
}
|
||||
|
||||
processedAll = true;
|
||||
foundDivisor = 0UL;
|
||||
return false;
|
||||
}
|
||||
|
||||
private bool CheckDivisorsLarge(
|
||||
ulong prime,
|
||||
BigInteger allowedMax,
|
||||
BigInteger minK,
|
||||
BigInteger step,
|
||||
out bool processedAll,
|
||||
out BigInteger foundDivisor)
|
||||
{
|
||||
processedAll = true;
|
||||
foundDivisor = BigInteger.Zero;
|
||||
BigInteger currentK = minK < BigInteger.One ? BigInteger.One : minK;
|
||||
BigInteger divisor = (step * currentK) + BigInteger.One;
|
||||
if (allowedMax.IsZero)
|
||||
{
|
||||
processedAll = false;
|
||||
return false;
|
||||
}
|
||||
if (divisor > allowedMax)
|
||||
{
|
||||
return false;
|
||||
}
|
||||
|
||||
LastDigit lastDigit = (prime & 3UL) == 3UL ? LastDigit.Seven : LastDigit.One;
|
||||
ushort decimalMask = DivisorGenerator.GetDecimalMask(lastDigit);
|
||||
|
||||
var rem10 = new BigIntegerCycleRemainderStepper(10);
|
||||
var rem8 = new BigIntegerCycleRemainderStepper(8);
|
||||
var rem5 = new BigIntegerCycleRemainderStepper(5);
|
||||
var rem3 = new BigIntegerCycleRemainderStepper(3);
|
||||
var rem7 = new BigIntegerCycleRemainderStepper(7);
|
||||
var rem11 = new BigIntegerCycleRemainderStepper(11);
|
||||
var rem13 = new BigIntegerCycleRemainderStepper(13);
|
||||
var rem17 = new BigIntegerCycleRemainderStepper(17);
|
||||
var rem19 = new BigIntegerCycleRemainderStepper(19);
|
||||
|
||||
byte remainder10 = (byte)rem10.Initialize(divisor);
|
||||
byte remainder8 = (byte)rem8.Initialize(divisor);
|
||||
byte remainder5 = (byte)rem5.Initialize(divisor);
|
||||
byte remainder3 = (byte)rem3.Initialize(divisor);
|
||||
byte remainder7 = (byte)rem7.Initialize(divisor);
|
||||
byte remainder11 = (byte)rem11.Initialize(divisor);
|
||||
byte remainder13 = (byte)rem13.Initialize(divisor);
|
||||
byte remainder17 = (byte)rem17.Initialize(divisor);
|
||||
byte remainder19 = (byte)rem19.Initialize(divisor);
|
||||
|
||||
while (divisor <= allowedMax)
|
||||
{
|
||||
bool passesSmallModuli = remainder3 != 0 && remainder5 != 0 && remainder7 != 0 && remainder11 != 0 && remainder13 != 0 && remainder17 != 0 && remainder19 != 0;
|
||||
if (passesSmallModuli && (remainder8 == 1 || remainder8 == 7) && ((decimalMask >> remainder10) & 1) != 0)
|
||||
{
|
||||
if (MersenneNumberDivisorByDivisorTester.IsProbablePrimeBigInteger(divisor))
|
||||
{
|
||||
BigInteger powResult = BigInteger.ModPow(2, prime, divisor);
|
||||
RecordState(StateFilePath, currentK);
|
||||
if (powResult.IsOne)
|
||||
{
|
||||
foundDivisor = divisor;
|
||||
processedAll = true;
|
||||
return true;
|
||||
}
|
||||
}
|
||||
else
|
||||
{
|
||||
RecordState(StateFilePath, currentK);
|
||||
}
|
||||
}
|
||||
|
||||
currentK += BigInteger.One;
|
||||
divisor += step;
|
||||
remainder10 = (byte)rem10.ComputeNext(divisor);
|
||||
remainder8 = (byte)rem8.ComputeNext(divisor);
|
||||
remainder5 = (byte)rem5.ComputeNext(divisor);
|
||||
remainder3 = (byte)rem3.ComputeNext(divisor);
|
||||
remainder7 = (byte)rem7.ComputeNext(divisor);
|
||||
remainder11 = (byte)rem11.ComputeNext(divisor);
|
||||
remainder13 = (byte)rem13.ComputeNext(divisor);
|
||||
remainder17 = (byte)rem17.ComputeNext(divisor);
|
||||
remainder19 = (byte)rem19.ComputeNext(divisor);
|
||||
|
||||
if (divisor > allowedMax)
|
||||
{
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
processedAll = true;
|
||||
foundDivisor = BigInteger.Zero;
|
||||
return false;
|
||||
}
|
||||
|
||||
private bool CheckDivisors64Range(
|
||||
ulong prime,
|
||||
ulong step,
|
||||
ulong allowedMax,
|
||||
ulong startK,
|
||||
ulong endK,
|
||||
ref ulong currentK,
|
||||
out bool processedAll,
|
||||
out ulong foundDivisor)
|
||||
{
|
||||
if (startK < 1UL || endK < startK)
|
||||
{
|
||||
processedAll = true;
|
||||
foundDivisor = 0UL;
|
||||
return false;
|
||||
}
|
||||
currentK = startK;
|
||||
|
||||
UInt128 step128 = step;
|
||||
UInt128 allowedMax128 = allowedMax;
|
||||
UInt128 startDivisor128 = (step128 * startK) + UInt128.One;
|
||||
if (startDivisor128 > allowedMax128)
|
||||
{
|
||||
processedAll = true;
|
||||
foundDivisor = 0UL;
|
||||
return false;
|
||||
}
|
||||
|
||||
UInt128 rangeLimit128 = (step128 * endK) + UInt128.One;
|
||||
if (rangeLimit128 > allowedMax128)
|
||||
{
|
||||
rangeLimit128 = allowedMax128;
|
||||
}
|
||||
|
||||
ulong startDivisor = (ulong)startDivisor128;
|
||||
ulong rangeLimit = (ulong)rangeLimit128;
|
||||
|
||||
var residueStepper = new MersenneDivisorResidueStepper(prime, (GpuUInt128)step128, (GpuUInt128)startDivisor128);
|
||||
|
||||
return CheckDivisors64(
|
||||
prime,
|
||||
step,
|
||||
rangeLimit,
|
||||
startDivisor,
|
||||
ref residueStepper,
|
||||
ref currentK,
|
||||
out processedAll,
|
||||
out foundDivisor);
|
||||
}
|
||||
|
||||
private bool CheckDivisors64(
|
||||
ulong prime,
|
||||
ulong step,
|
||||
ulong limit,
|
||||
ulong divisor,
|
||||
ref MersenneDivisorResidueStepper residueStepper,
|
||||
ref ulong currentK,
|
||||
out bool processedAll,
|
||||
out ulong foundDivisor)
|
||||
{
|
||||
bool canAdvance = step <= limit;
|
||||
if (!canAdvance)
|
||||
{
|
||||
if (divisor <= limit && residueStepper.IsAdmissible())
|
||||
{
|
||||
MontgomeryDivisorData divisorData = MontgomeryDivisorData.FromModulus(divisor);
|
||||
ulong divisorCycle;
|
||||
if (!MersenneNumberDivisorByDivisorTester.TryCalculateCycleLengthForExponentCpu(
|
||||
divisor,
|
||||
prime,
|
||||
divisorData,
|
||||
out ulong computedCycle,
|
||||
out bool primeOrderFailed) || computedCycle == 0UL)
|
||||
{
|
||||
divisorCycle = MersenneNumberDivisorByDivisorTester.CalculateCycleLengthCpu(
|
||||
divisor,
|
||||
divisorData,
|
||||
skipPrimeOrderHeuristic: primeOrderFailed);
|
||||
}
|
||||
else
|
||||
{
|
||||
divisorCycle = computedCycle;
|
||||
}
|
||||
|
||||
if (divisorCycle == prime)
|
||||
{
|
||||
foundDivisor = divisor;
|
||||
processedAll = true;
|
||||
return true;
|
||||
}
|
||||
|
||||
if (divisorCycle == 0UL)
|
||||
{
|
||||
Console.WriteLine($"Divisor cycle was not calculated for {prime}");
|
||||
}
|
||||
}
|
||||
|
||||
processedAll = true;
|
||||
foundDivisor = 0UL;
|
||||
return false;
|
||||
}
|
||||
|
||||
if (divisor > limit)
|
||||
{
|
||||
processedAll = true;
|
||||
foundDivisor = 0UL;
|
||||
return false;
|
||||
}
|
||||
|
||||
ulong remainingIterations = ((limit - divisor) / step) + 1UL;
|
||||
while (true)
|
||||
{
|
||||
if (residueStepper.IsAdmissible())
|
||||
{
|
||||
MontgomeryDivisorData divisorData = MontgomeryDivisorData.FromModulus(divisor);
|
||||
ulong divisorCycle;
|
||||
if (!MersenneNumberDivisorByDivisorTester.TryCalculateCycleLengthForExponentCpu(
|
||||
divisor,
|
||||
prime,
|
||||
divisorData,
|
||||
out ulong computedCycle,
|
||||
out bool primeOrderFailed) || computedCycle == 0UL)
|
||||
{
|
||||
divisorCycle = MersenneNumberDivisorByDivisorTester.CalculateCycleLengthCpu(
|
||||
divisor,
|
||||
divisorData,
|
||||
skipPrimeOrderHeuristic: primeOrderFailed);
|
||||
}
|
||||
else
|
||||
{
|
||||
divisorCycle = computedCycle;
|
||||
}
|
||||
|
||||
RecordState(StateFilePath, currentK);
|
||||
if (divisorCycle == prime)
|
||||
{
|
||||
foundDivisor = divisor;
|
||||
processedAll = true;
|
||||
return true;
|
||||
}
|
||||
|
||||
if (divisorCycle == 0UL)
|
||||
{
|
||||
Console.WriteLine($"Divisor cycle was not calculated for {prime}");
|
||||
}
|
||||
}
|
||||
|
||||
remainingIterations--;
|
||||
if (remainingIterations == 0UL)
|
||||
{
|
||||
processedAll = true;
|
||||
foundDivisor = 0UL;
|
||||
return false;
|
||||
}
|
||||
|
||||
divisor += step;
|
||||
currentK++;
|
||||
residueStepper.Advance();
|
||||
}
|
||||
}
|
||||
|
||||
private void RecordState(in string path, BigInteger k)
|
||||
{
|
||||
|
||||
if (k <= _lastSavedK)
|
||||
{
|
||||
return;
|
||||
}
|
||||
|
||||
int next = _stateCounter + 1;
|
||||
if (next >= PerfectNumberConstants.ByDivisorStateSaveInterval)
|
||||
{
|
||||
string? directory = Path.GetDirectoryName(path);
|
||||
if (!string.IsNullOrEmpty(directory))
|
||||
{
|
||||
Directory.CreateDirectory(directory);
|
||||
}
|
||||
|
||||
File.AppendAllText(path, k.ToString(CultureInfo.InvariantCulture) + Environment.NewLine);
|
||||
_stateCounter = 0;
|
||||
_lastSavedK = k;
|
||||
}
|
||||
else
|
||||
{
|
||||
_stateCounter = next;
|
||||
}
|
||||
}
|
||||
}
|
||||
@@ -0,0 +1,600 @@
|
||||
using System.Numerics;
|
||||
using System.Runtime.CompilerServices;
|
||||
using System.Globalization;
|
||||
using PerfectNumbers.Core.Gpu;
|
||||
using PerfectNumbers.Core.Gpu.Accelerators;
|
||||
|
||||
namespace PerfectNumbers.Core.Cpu;
|
||||
|
||||
public struct MersenneNumberDivisorByDivisorCpuTesterWithGpuOrder() : IMersenneNumberDivisorByDivisorTester
|
||||
{
|
||||
public BigInteger DivisorLimit;
|
||||
public BigInteger MinK = EnvironmentConfiguration.MinK;
|
||||
public readonly PrimeOrderCalculatorAccelerator Accelerator = PrimeOrderCalculatorAccelerator.Rent(1);
|
||||
|
||||
#pragma warning disable CS8618 // StateFilePath is always set on EvenPerfectBitScanner execution path when ResumeFromState is called.
|
||||
private string StateFilePath;
|
||||
#pragma warning restore CS8618 // Non-nullable field must contain a non-null value when exiting constructor. Consider adding the 'required' modifier or declaring as nullable.
|
||||
|
||||
private int _stateCounter;
|
||||
private BigInteger _lastSavedK;
|
||||
|
||||
private GpuUInt128WorkSet _divisorScanGpuWorkSet;
|
||||
|
||||
[MethodImpl(MethodImplOptions.AggressiveInlining | MethodImplOptions.AggressiveOptimization)]
|
||||
public void ResetStateTracking()
|
||||
{
|
||||
_stateCounter = 0;
|
||||
}
|
||||
|
||||
[MethodImpl(MethodImplOptions.AggressiveInlining | MethodImplOptions.AggressiveOptimization)]
|
||||
public void ResumeFromState(in string stateFile, in BigInteger lastSavedK, in BigInteger minK)
|
||||
{
|
||||
StateFilePath = stateFile;
|
||||
_lastSavedK = lastSavedK;
|
||||
MinK = minK;
|
||||
_stateCounter = 0;
|
||||
}
|
||||
|
||||
public bool IsPrime(ulong prime, out bool divisorsExhausted, out BigInteger divisor)
|
||||
{
|
||||
BigInteger allowedMax = MersenneNumberDivisorByDivisorTester.ComputeAllowedMaxDivisorBig(prime, DivisorLimit);
|
||||
|
||||
// The CPU by-divisor run always hands us primes with enormous divisor limits, so the fallback below never executes.
|
||||
// if (allowedMax < 3UL)
|
||||
// {
|
||||
// // EvenPerfectBitScanner routes primes below the small-divisor cutoff to the GPU path, so the CPU path still sees
|
||||
// // trivial candidates during targeted tests. Short-circuit here to keep those runs aligned with the production flow.
|
||||
// divisorsExhausted = true;
|
||||
// return true;
|
||||
// }
|
||||
|
||||
|
||||
bool composite = CheckDivisors(
|
||||
prime,
|
||||
allowedMax,
|
||||
MinK,
|
||||
out bool processedAll,
|
||||
out divisor);
|
||||
|
||||
if (composite)
|
||||
{
|
||||
divisorsExhausted = true;
|
||||
return false;
|
||||
}
|
||||
|
||||
divisorsExhausted = processedAll || composite;
|
||||
divisor = BigInteger.Zero;
|
||||
return true;
|
||||
}
|
||||
|
||||
public void PrepareCandidates(ulong maxPrime, in ReadOnlySpan<ulong> primes, Span<ulong> allowedMaxValues)
|
||||
{
|
||||
BigInteger divisorLimitBigInteger = MersenneNumberDivisorByDivisorTester.ComputeDivisorLimitFromMaxPrimeBig(maxPrime);
|
||||
DivisorLimit = divisorLimitBigInteger;
|
||||
ulong divisorLimit = MersenneNumberDivisorByDivisorTester.GetAllowedDivisorLimitForSpan(divisorLimitBigInteger);
|
||||
int length = primes.Length;
|
||||
for (int index = 0; index < length; index++)
|
||||
{
|
||||
allowedMaxValues[index] = MersenneNumberDivisorByDivisorTester.ComputeAllowedMaxDivisor(primes[index], divisorLimit);
|
||||
}
|
||||
}
|
||||
|
||||
[MethodImpl(MethodImplOptions.AggressiveInlining | MethodImplOptions.AggressiveOptimization)]
|
||||
public IMersenneNumberDivisorByDivisorTester.IDivisorScanSession CreateDivisorSession(PrimeOrderCalculatorAccelerator gpu)
|
||||
{
|
||||
var session = new MersenneCpuDivisorScanSessionWithGpuOrder();
|
||||
session.Configure(gpu);
|
||||
return session;
|
||||
}
|
||||
|
||||
private bool CheckDivisors(
|
||||
ulong prime,
|
||||
BigInteger allowedMax,
|
||||
BigInteger minK,
|
||||
out bool processedAll,
|
||||
out BigInteger foundDivisor)
|
||||
{
|
||||
BigInteger normalizedMinK = minK < BigInteger.One ? BigInteger.One : minK;
|
||||
BigInteger step = ((BigInteger)prime) << 1;
|
||||
BigInteger firstDivisor = (step * normalizedMinK) + BigInteger.One;
|
||||
bool unlimited = allowedMax.IsZero;
|
||||
|
||||
bool fits64 = normalizedMinK <= ulong.MaxValue && firstDivisor <= ulong.MaxValue;
|
||||
bool limitFits64 = unlimited || allowedMax <= ulong.MaxValue;
|
||||
if (fits64 && limitFits64)
|
||||
{
|
||||
ulong allowedMax64 = unlimited ? ulong.MaxValue : (ulong)allowedMax;
|
||||
bool composite64 = CheckDivisors64Bit(
|
||||
prime,
|
||||
allowedMax64,
|
||||
(ulong)normalizedMinK,
|
||||
out processedAll,
|
||||
out ulong foundDivisor64);
|
||||
foundDivisor = foundDivisor64;
|
||||
return composite64;
|
||||
}
|
||||
|
||||
if (fits64 && allowedMax > ulong.MaxValue)
|
||||
{
|
||||
ulong allowedMax64 = ulong.MaxValue;
|
||||
bool composite64 = CheckDivisors64Bit(
|
||||
prime,
|
||||
allowedMax64,
|
||||
(ulong)normalizedMinK,
|
||||
out processedAll,
|
||||
out ulong foundDivisor64);
|
||||
if (composite64)
|
||||
{
|
||||
foundDivisor = foundDivisor64;
|
||||
return true;
|
||||
}
|
||||
|
||||
BigInteger iterations = ((BigInteger)(allowedMax64 - (ulong)firstDivisor) / (ulong)step) + BigInteger.One;
|
||||
BigInteger nextK = normalizedMinK + iterations;
|
||||
return CheckDivisorsLarge(
|
||||
prime,
|
||||
allowedMax,
|
||||
nextK,
|
||||
step,
|
||||
out processedAll,
|
||||
out foundDivisor);
|
||||
}
|
||||
|
||||
return CheckDivisorsLarge(
|
||||
prime,
|
||||
allowedMax,
|
||||
normalizedMinK,
|
||||
step,
|
||||
out processedAll,
|
||||
out foundDivisor);
|
||||
}
|
||||
|
||||
private bool CheckDivisors64Bit(
|
||||
ulong prime,
|
||||
ulong allowedMax,
|
||||
ulong minK,
|
||||
out bool processedAll,
|
||||
out ulong foundDivisor)
|
||||
{
|
||||
foundDivisor = 0UL;
|
||||
ulong currentK = minK < 1UL ? 1UL : minK;
|
||||
|
||||
// The EvenPerfectBitScanner feeds primes >= 138,000,000 here, so allowedMax >= 3 in production runs.
|
||||
// Keeping the guard commented out documents the reasoning for benchmarks and tests.
|
||||
// if (allowedMax < 3UL)
|
||||
// {
|
||||
// return false;
|
||||
// }
|
||||
|
||||
ref GpuUInt128WorkSet workSet = ref _divisorScanGpuWorkSet;
|
||||
|
||||
ref GpuUInt128 step = ref workSet.Step;
|
||||
step.High = 0UL;
|
||||
step.Low = prime;
|
||||
step.ShiftLeft(1);
|
||||
|
||||
ref GpuUInt128 limit = ref workSet.Limit;
|
||||
limit.High = 0UL;
|
||||
limit.Low = allowedMax;
|
||||
|
||||
ref GpuUInt128 divisor = ref workSet.Divisor;
|
||||
divisor.High = step.High;
|
||||
divisor.Low = step.Low;
|
||||
divisor.Add(1UL);
|
||||
if (minK > 1UL)
|
||||
{
|
||||
GpuUInt128 offset = new(minK - 1UL);
|
||||
divisor = step * offset;
|
||||
divisor.Add(1UL);
|
||||
}
|
||||
|
||||
if (divisor.CompareTo(limit) > 0)
|
||||
{
|
||||
processedAll = true;
|
||||
foundDivisor = 0UL;
|
||||
return false;
|
||||
}
|
||||
|
||||
// Intentionally recomputes factorizations without a per-thread cache.
|
||||
// The previous factor cache recorded virtually no hits and only slowed down the scan.
|
||||
|
||||
ulong stepHigh = step.High;
|
||||
ulong stepLow = step.Low;
|
||||
ulong limitHigh = limit.High;
|
||||
|
||||
if (stepHigh == 0UL && limitHigh == 0UL)
|
||||
{
|
||||
ulong maxK = allowedMax > 0UL ? (allowedMax - 1UL) / stepLow : 0UL;
|
||||
if (maxK == 0UL)
|
||||
{
|
||||
processedAll = true;
|
||||
foundDivisor = 0UL;
|
||||
return false;
|
||||
}
|
||||
|
||||
ulong startK = minK < 1UL ? 1UL : minK;
|
||||
bool processedTop = true;
|
||||
bool processedBottom = true;
|
||||
bool composite = false;
|
||||
|
||||
if (startK <= maxK)
|
||||
{
|
||||
composite = CheckDivisors64Range(
|
||||
prime,
|
||||
stepLow,
|
||||
allowedMax,
|
||||
startK,
|
||||
maxK,
|
||||
ref currentK,
|
||||
out processedTop,
|
||||
out foundDivisor);
|
||||
if (composite)
|
||||
{
|
||||
processedAll = true;
|
||||
return true;
|
||||
}
|
||||
}
|
||||
|
||||
ulong lowerEnd = startK > 1UL ? startK - 1UL : 0UL;
|
||||
if (lowerEnd >= 1UL && startK == 1UL)
|
||||
{
|
||||
lowerEnd = Math.Min(lowerEnd, maxK);
|
||||
currentK = 1UL;
|
||||
composite = CheckDivisors64Range(
|
||||
prime,
|
||||
stepLow,
|
||||
allowedMax,
|
||||
1UL,
|
||||
lowerEnd,
|
||||
ref currentK,
|
||||
out processedBottom,
|
||||
out foundDivisor);
|
||||
}
|
||||
|
||||
processedAll = processedTop && processedBottom;
|
||||
return composite;
|
||||
}
|
||||
|
||||
PrimeOrderCalculatorAccelerator gpu = Accelerator;
|
||||
var residueStepper = new MersenneDivisorResidueStepper(prime, step, divisor);
|
||||
while (divisor.CompareTo(limit) <= 0)
|
||||
{
|
||||
if (residueStepper.IsAdmissible())
|
||||
{
|
||||
ulong candidate = divisor.Low;
|
||||
MontgomeryDivisorData divisorData = MontgomeryDivisorData.FromModulus(candidate);
|
||||
ulong divisorCycle;
|
||||
// Divisors generated from 2 * k * p + 1 exceed the small-cycle snapshot when p >= 138,000,000, so the short path below never runs.
|
||||
if (!MersenneNumberDivisorByDivisorTester.TryCalculateCycleLengthForExponentGpu(
|
||||
candidate,
|
||||
gpu,
|
||||
prime,
|
||||
divisorData,
|
||||
out ulong computedCycle,
|
||||
out bool primeOrderFailed) || computedCycle == 0UL)
|
||||
{
|
||||
// Divisors produced by 2 * k * p + 1 always exceed PerfectNumberConstants.MaxQForDivisorCycles
|
||||
// for the exponents scanned here, so skip the unused cache fallback and compute directly.
|
||||
divisorCycle = MersenneNumberDivisorByDivisorTester.CalculateCycleLengthGpu(
|
||||
|
||||
candidate,
|
||||
gpu,
|
||||
divisorData,
|
||||
skipPrimeOrderHeuristic: primeOrderFailed);
|
||||
}
|
||||
else
|
||||
{
|
||||
divisorCycle = computedCycle;
|
||||
}
|
||||
|
||||
RecordState(currentK);
|
||||
if (divisorCycle == prime)
|
||||
{
|
||||
// A cycle equal to the tested exponent (which is prime in this path) guarantees that the candidate divides
|
||||
// the corresponding Mersenne number because the order of 2 modulo the divisor is exactly p.
|
||||
foundDivisor = candidate;
|
||||
processedAll = true;
|
||||
return true;
|
||||
}
|
||||
|
||||
if (divisorCycle == 0UL)
|
||||
{
|
||||
Console.WriteLine($"Divisor cycle was not calculated for {prime}");
|
||||
}
|
||||
}
|
||||
|
||||
divisor.Add(step);
|
||||
currentK++;
|
||||
residueStepper.Advance();
|
||||
}
|
||||
|
||||
processedAll = true;
|
||||
foundDivisor = 0UL;
|
||||
return false;
|
||||
}
|
||||
|
||||
private bool CheckDivisorsLarge(
|
||||
ulong prime,
|
||||
BigInteger allowedMax,
|
||||
BigInteger minK,
|
||||
BigInteger step,
|
||||
out bool processedAll,
|
||||
out BigInteger foundDivisor)
|
||||
{
|
||||
processedAll = true;
|
||||
foundDivisor = BigInteger.Zero;
|
||||
BigInteger currentK = minK < BigInteger.One ? BigInteger.One : minK;
|
||||
BigInteger divisor = (step * currentK) + BigInteger.One;
|
||||
if (allowedMax.IsZero)
|
||||
{
|
||||
processedAll = false;
|
||||
return false;
|
||||
}
|
||||
if (divisor > allowedMax)
|
||||
{
|
||||
return false;
|
||||
}
|
||||
|
||||
LastDigit lastDigit = (prime & 3UL) == 3UL ? LastDigit.Seven : LastDigit.One;
|
||||
ushort decimalMask = DivisorGenerator.GetDecimalMask(lastDigit);
|
||||
|
||||
var rem10 = new BigIntegerCycleRemainderStepper(10);
|
||||
var rem8 = new BigIntegerCycleRemainderStepper(8);
|
||||
var rem5 = new BigIntegerCycleRemainderStepper(5);
|
||||
var rem3 = new BigIntegerCycleRemainderStepper(3);
|
||||
var rem7 = new BigIntegerCycleRemainderStepper(7);
|
||||
var rem11 = new BigIntegerCycleRemainderStepper(11);
|
||||
var rem13 = new BigIntegerCycleRemainderStepper(13);
|
||||
var rem17 = new BigIntegerCycleRemainderStepper(17);
|
||||
var rem19 = new BigIntegerCycleRemainderStepper(19);
|
||||
|
||||
byte remainder10 = (byte)rem10.Initialize(divisor);
|
||||
byte remainder8 = (byte)rem8.Initialize(divisor);
|
||||
byte remainder5 = (byte)rem5.Initialize(divisor);
|
||||
byte remainder3 = (byte)rem3.Initialize(divisor);
|
||||
byte remainder7 = (byte)rem7.Initialize(divisor);
|
||||
byte remainder11 = (byte)rem11.Initialize(divisor);
|
||||
byte remainder13 = (byte)rem13.Initialize(divisor);
|
||||
byte remainder17 = (byte)rem17.Initialize(divisor);
|
||||
byte remainder19 = (byte)rem19.Initialize(divisor);
|
||||
|
||||
while (divisor <= allowedMax)
|
||||
{
|
||||
bool passesSmallModuli = remainder3 != 0 && remainder5 != 0 && remainder7 != 0 && remainder11 != 0 && remainder13 != 0 && remainder17 != 0 && remainder19 != 0;
|
||||
if (passesSmallModuli && (remainder8 == 1 || remainder8 == 7) && ((decimalMask >> remainder10) & 1) != 0)
|
||||
{
|
||||
if (MersenneNumberDivisorByDivisorTester.IsProbablePrimeBigInteger(divisor))
|
||||
{
|
||||
BigInteger powResult = BigInteger.ModPow(2, prime, divisor);
|
||||
RecordState(currentK);
|
||||
if (powResult.IsOne)
|
||||
{
|
||||
foundDivisor = divisor;
|
||||
processedAll = true;
|
||||
return true;
|
||||
}
|
||||
}
|
||||
else
|
||||
{
|
||||
RecordState(currentK);
|
||||
}
|
||||
}
|
||||
|
||||
currentK += BigInteger.One;
|
||||
divisor += step;
|
||||
remainder10 = (byte)rem10.ComputeNext(divisor);
|
||||
remainder8 = (byte)rem8.ComputeNext(divisor);
|
||||
remainder5 = (byte)rem5.ComputeNext(divisor);
|
||||
remainder3 = (byte)rem3.ComputeNext(divisor);
|
||||
remainder7 = (byte)rem7.ComputeNext(divisor);
|
||||
remainder11 = (byte)rem11.ComputeNext(divisor);
|
||||
remainder13 = (byte)rem13.ComputeNext(divisor);
|
||||
remainder17 = (byte)rem17.ComputeNext(divisor);
|
||||
remainder19 = (byte)rem19.ComputeNext(divisor);
|
||||
|
||||
if (divisor > allowedMax)
|
||||
{
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
processedAll = true;
|
||||
foundDivisor = BigInteger.Zero;
|
||||
return false;
|
||||
}
|
||||
|
||||
private bool CheckDivisors64Range(
|
||||
ulong prime,
|
||||
ulong step,
|
||||
ulong allowedMax,
|
||||
ulong startK,
|
||||
ulong endK,
|
||||
ref ulong currentK,
|
||||
out bool processedAll,
|
||||
out ulong foundDivisor)
|
||||
{
|
||||
if (startK < 1UL || endK < startK)
|
||||
{
|
||||
processedAll = true;
|
||||
foundDivisor = 0UL;
|
||||
return false;
|
||||
}
|
||||
currentK = startK;
|
||||
|
||||
UInt128 step128 = step;
|
||||
UInt128 allowedMax128 = allowedMax;
|
||||
UInt128 startDivisor128 = (step128 * startK) + UInt128.One;
|
||||
if (startDivisor128 > allowedMax128)
|
||||
{
|
||||
processedAll = true;
|
||||
foundDivisor = 0UL;
|
||||
return false;
|
||||
}
|
||||
|
||||
UInt128 rangeLimit128 = (step128 * endK) + UInt128.One;
|
||||
if (rangeLimit128 > allowedMax128)
|
||||
{
|
||||
rangeLimit128 = allowedMax128;
|
||||
}
|
||||
|
||||
ulong startDivisor = (ulong)startDivisor128;
|
||||
ulong rangeLimit = (ulong)rangeLimit128;
|
||||
|
||||
var residueStepper = new MersenneDivisorResidueStepper(prime, (GpuUInt128)step128, (GpuUInt128)startDivisor128);
|
||||
|
||||
return CheckDivisors64(
|
||||
prime,
|
||||
step,
|
||||
rangeLimit,
|
||||
startDivisor,
|
||||
ref residueStepper,
|
||||
ref currentK,
|
||||
out processedAll,
|
||||
out foundDivisor);
|
||||
}
|
||||
|
||||
private bool CheckDivisors64(
|
||||
ulong prime,
|
||||
ulong step,
|
||||
ulong limit,
|
||||
ulong divisor,
|
||||
ref MersenneDivisorResidueStepper residueStepper,
|
||||
ref ulong currentK,
|
||||
out bool processedAll,
|
||||
out ulong foundDivisor)
|
||||
{
|
||||
PrimeOrderCalculatorAccelerator gpu = Accelerator;
|
||||
|
||||
if (step > limit)
|
||||
{
|
||||
if (divisor <= limit && residueStepper.IsAdmissible())
|
||||
{
|
||||
MontgomeryDivisorData divisorData = MontgomeryDivisorData.FromModulus(divisor);
|
||||
ulong divisorCycle;
|
||||
if (!MersenneNumberDivisorByDivisorTester.TryCalculateCycleLengthForExponentGpu(
|
||||
divisor,
|
||||
gpu,
|
||||
prime,
|
||||
divisorData,
|
||||
out ulong computedCycle,
|
||||
out bool primeOrderFailed) || computedCycle == 0UL)
|
||||
{
|
||||
divisorCycle = MersenneNumberDivisorByDivisorTester.CalculateCycleLengthGpu(
|
||||
divisor,
|
||||
gpu,
|
||||
divisorData,
|
||||
skipPrimeOrderHeuristic: primeOrderFailed);
|
||||
}
|
||||
else
|
||||
{
|
||||
divisorCycle = computedCycle;
|
||||
}
|
||||
|
||||
if (divisorCycle == prime)
|
||||
{
|
||||
foundDivisor = divisor;
|
||||
processedAll = true;
|
||||
return true;
|
||||
}
|
||||
|
||||
if (divisorCycle == 0UL)
|
||||
{
|
||||
Console.WriteLine($"Divisor cycle was not calculated for {prime}");
|
||||
}
|
||||
}
|
||||
|
||||
processedAll = true;
|
||||
foundDivisor = 0UL;
|
||||
return false;
|
||||
}
|
||||
|
||||
if (divisor > limit)
|
||||
{
|
||||
processedAll = true;
|
||||
foundDivisor = 0UL;
|
||||
return false;
|
||||
}
|
||||
|
||||
ulong remainingIterations = ((limit - divisor) / step) + 1UL;
|
||||
while (true)
|
||||
{
|
||||
if (residueStepper.IsAdmissible())
|
||||
{
|
||||
MontgomeryDivisorData divisorData = MontgomeryDivisorData.FromModulus(divisor);
|
||||
ulong divisorCycle;
|
||||
if (!MersenneNumberDivisorByDivisorTester.TryCalculateCycleLengthForExponentGpu(
|
||||
divisor,
|
||||
gpu,
|
||||
prime,
|
||||
divisorData,
|
||||
out ulong computedCycle,
|
||||
out bool primeOrderFailed) || computedCycle == 0UL)
|
||||
{
|
||||
divisorCycle = MersenneNumberDivisorByDivisorTester.CalculateCycleLengthGpu(
|
||||
divisor,
|
||||
gpu,
|
||||
divisorData,
|
||||
skipPrimeOrderHeuristic: primeOrderFailed);
|
||||
}
|
||||
else
|
||||
{
|
||||
divisorCycle = computedCycle;
|
||||
}
|
||||
|
||||
RecordState(currentK);
|
||||
if (divisorCycle == prime)
|
||||
{
|
||||
foundDivisor = divisor;
|
||||
processedAll = true;
|
||||
return true;
|
||||
}
|
||||
|
||||
if (divisorCycle == 0UL)
|
||||
{
|
||||
Console.WriteLine($"Divisor cycle was not calculated for {prime}");
|
||||
}
|
||||
}
|
||||
|
||||
remainingIterations--;
|
||||
if (remainingIterations == 0UL)
|
||||
{
|
||||
processedAll = true;
|
||||
foundDivisor = 0UL;
|
||||
return false;
|
||||
}
|
||||
|
||||
divisor += step;
|
||||
currentK++;
|
||||
residueStepper.Advance();
|
||||
}
|
||||
}
|
||||
|
||||
private void RecordState(BigInteger k)
|
||||
{
|
||||
string path = StateFilePath;
|
||||
|
||||
if (k <= _lastSavedK)
|
||||
{
|
||||
return;
|
||||
}
|
||||
|
||||
int next = _stateCounter + 1;
|
||||
if (next >= PerfectNumberConstants.ByDivisorStateSaveInterval)
|
||||
{
|
||||
string? directory = Path.GetDirectoryName(path);
|
||||
if (!string.IsNullOrEmpty(directory))
|
||||
{
|
||||
Directory.CreateDirectory(directory);
|
||||
}
|
||||
|
||||
File.AppendAllText(path, k.ToString(CultureInfo.InvariantCulture) + Environment.NewLine);
|
||||
_stateCounter = 0;
|
||||
_lastSavedK = k;
|
||||
}
|
||||
else
|
||||
{
|
||||
_stateCounter = next;
|
||||
}
|
||||
}
|
||||
}
|
||||
@@ -0,0 +1,598 @@
|
||||
using System.Numerics;
|
||||
using System.Runtime.CompilerServices;
|
||||
using System.Globalization;
|
||||
using PerfectNumbers.Core.Gpu;
|
||||
using PerfectNumbers.Core.Gpu.Accelerators;
|
||||
|
||||
namespace PerfectNumbers.Core.Cpu;
|
||||
|
||||
public struct MersenneNumberDivisorByDivisorCpuTesterWithHybridOrder() : IMersenneNumberDivisorByDivisorTester
|
||||
{
|
||||
public BigInteger DivisorLimit;
|
||||
public BigInteger MinK = EnvironmentConfiguration.MinK;
|
||||
public readonly PrimeOrderCalculatorAccelerator Accelerator = PrimeOrderCalculatorAccelerator.Rent(1);
|
||||
|
||||
#pragma warning disable CS8618 // StateFilePath is always set on EvenPerfectBitScanner execution path when ResumeFromState is called.
|
||||
private string StateFilePath;
|
||||
#pragma warning restore CS8618 // Non-nullable field must contain a non-null value when exiting constructor. Consider adding the 'required' modifier or declaring as nullable.
|
||||
|
||||
private int _stateCounter;
|
||||
private BigInteger _lastSavedK;
|
||||
|
||||
private GpuUInt128WorkSet _divisorScanGpuWorkSet;
|
||||
|
||||
public void ResetStateTracking()
|
||||
{
|
||||
_stateCounter = 0;
|
||||
}
|
||||
|
||||
public void ResumeFromState(in string stateFile, in BigInteger lastSavedK, in BigInteger minK)
|
||||
{
|
||||
StateFilePath = stateFile;
|
||||
_lastSavedK = lastSavedK;
|
||||
MinK = minK;
|
||||
_stateCounter = 0;
|
||||
}
|
||||
|
||||
public bool IsPrime(ulong prime, out bool divisorsExhausted, out BigInteger divisor)
|
||||
{
|
||||
BigInteger allowedMax = MersenneNumberDivisorByDivisorTester.ComputeAllowedMaxDivisorBig(prime, DivisorLimit);
|
||||
|
||||
// The CPU by-divisor run always hands us primes with enormous divisor limits, so the fallback below never executes.
|
||||
// if (allowedMax < 3UL)
|
||||
// {
|
||||
// // EvenPerfectBitScanner routes primes below the small-divisor cutoff to the GPU path, so the CPU path still sees
|
||||
// // trivial candidates during targeted tests. Short-circuit here to keep those runs aligned with the production flow.
|
||||
// divisorsExhausted = true;
|
||||
// return true;
|
||||
// }
|
||||
|
||||
|
||||
bool composite = CheckDivisors(
|
||||
prime,
|
||||
allowedMax,
|
||||
MinK,
|
||||
out bool processedAll,
|
||||
out divisor);
|
||||
|
||||
if (composite)
|
||||
{
|
||||
divisorsExhausted = true;
|
||||
return false;
|
||||
}
|
||||
|
||||
divisorsExhausted = processedAll || composite;
|
||||
divisor = BigInteger.Zero;
|
||||
return true;
|
||||
}
|
||||
|
||||
public void PrepareCandidates(ulong maxPrime, in ReadOnlySpan<ulong> primes, Span<ulong> allowedMaxValues)
|
||||
{
|
||||
BigInteger divisorLimitBigInteger = MersenneNumberDivisorByDivisorTester.ComputeDivisorLimitFromMaxPrimeBig(maxPrime);
|
||||
DivisorLimit = divisorLimitBigInteger;
|
||||
ulong divisorLimit = MersenneNumberDivisorByDivisorTester.GetAllowedDivisorLimitForSpan(divisorLimitBigInteger);
|
||||
int length = primes.Length;
|
||||
for (int index = 0; index < length; index++)
|
||||
{
|
||||
allowedMaxValues[index] = MersenneNumberDivisorByDivisorTester.ComputeAllowedMaxDivisor(primes[index], divisorLimit);
|
||||
}
|
||||
}
|
||||
|
||||
[MethodImpl(MethodImplOptions.AggressiveInlining | MethodImplOptions.AggressiveOptimization)]
|
||||
public readonly IMersenneNumberDivisorByDivisorTester.IDivisorScanSession CreateDivisorSession(PrimeOrderCalculatorAccelerator gpu)
|
||||
{
|
||||
var session = new MersenneCpuDivisorScanSessionWithHybridOrder();
|
||||
session.Configure(gpu);
|
||||
return session;
|
||||
}
|
||||
|
||||
private bool CheckDivisors(
|
||||
ulong prime,
|
||||
BigInteger allowedMax,
|
||||
BigInteger minK,
|
||||
out bool processedAll,
|
||||
out BigInteger foundDivisor)
|
||||
{
|
||||
BigInteger normalizedMinK = minK < BigInteger.One ? BigInteger.One : minK;
|
||||
BigInteger step = ((BigInteger)prime) << 1;
|
||||
BigInteger firstDivisor = (step * normalizedMinK) + BigInteger.One;
|
||||
bool unlimited = allowedMax.IsZero;
|
||||
|
||||
bool fits64 = normalizedMinK <= ulong.MaxValue && firstDivisor <= ulong.MaxValue;
|
||||
bool limitFits64 = unlimited || allowedMax <= ulong.MaxValue;
|
||||
if (fits64 && limitFits64)
|
||||
{
|
||||
ulong allowedMax64 = unlimited ? ulong.MaxValue : (ulong)allowedMax;
|
||||
bool composite64 = CheckDivisors64Bit(
|
||||
prime,
|
||||
allowedMax64,
|
||||
(ulong)normalizedMinK,
|
||||
out processedAll,
|
||||
out ulong foundDivisor64);
|
||||
foundDivisor = foundDivisor64;
|
||||
return composite64;
|
||||
}
|
||||
|
||||
if (fits64 && allowedMax > ulong.MaxValue)
|
||||
{
|
||||
ulong allowedMax64 = ulong.MaxValue;
|
||||
bool composite64 = CheckDivisors64Bit(
|
||||
prime,
|
||||
allowedMax64,
|
||||
(ulong)normalizedMinK,
|
||||
out processedAll,
|
||||
out ulong foundDivisor64);
|
||||
if (composite64)
|
||||
{
|
||||
foundDivisor = foundDivisor64;
|
||||
return true;
|
||||
}
|
||||
|
||||
BigInteger iterations = ((BigInteger)(allowedMax64 - (ulong)firstDivisor) / (ulong)step) + BigInteger.One;
|
||||
BigInteger nextK = normalizedMinK + iterations;
|
||||
return CheckDivisorsLarge(
|
||||
prime,
|
||||
allowedMax,
|
||||
nextK,
|
||||
step,
|
||||
out processedAll,
|
||||
out foundDivisor);
|
||||
}
|
||||
|
||||
return CheckDivisorsLarge(
|
||||
prime,
|
||||
allowedMax,
|
||||
normalizedMinK,
|
||||
step,
|
||||
out processedAll,
|
||||
out foundDivisor);
|
||||
}
|
||||
|
||||
private bool CheckDivisors64Bit(
|
||||
ulong prime,
|
||||
ulong allowedMax,
|
||||
ulong minK,
|
||||
out bool processedAll,
|
||||
out ulong foundDivisor)
|
||||
{
|
||||
foundDivisor = 0UL;
|
||||
ulong currentK = minK < 1UL ? 1UL : minK;
|
||||
|
||||
// The EvenPerfectBitScanner feeds primes >= 138,000,000 here, so allowedMax >= 3 in production runs.
|
||||
// Keeping the guard commented out documents the reasoning for benchmarks and tests.
|
||||
// if (allowedMax < 3UL)
|
||||
// {
|
||||
// return false;
|
||||
// }
|
||||
|
||||
ref GpuUInt128WorkSet workSet = ref _divisorScanGpuWorkSet;
|
||||
|
||||
ref GpuUInt128 step = ref workSet.Step;
|
||||
step.High = 0UL;
|
||||
step.Low = prime;
|
||||
step.ShiftLeft(1);
|
||||
|
||||
ref GpuUInt128 limit = ref workSet.Limit;
|
||||
limit.High = 0UL;
|
||||
limit.Low = allowedMax;
|
||||
|
||||
ref GpuUInt128 divisor = ref workSet.Divisor;
|
||||
divisor.High = step.High;
|
||||
divisor.Low = step.Low;
|
||||
divisor.Add(1UL);
|
||||
if (minK > 1UL)
|
||||
{
|
||||
GpuUInt128 offset = new(minK - 1UL);
|
||||
divisor = step * offset;
|
||||
divisor.Add(1UL);
|
||||
}
|
||||
|
||||
if (divisor.CompareTo(limit) > 0)
|
||||
{
|
||||
processedAll = true;
|
||||
foundDivisor = 0UL;
|
||||
return false;
|
||||
}
|
||||
|
||||
// Intentionally recomputes factorizations without a per-thread cache.
|
||||
// The previous factor cache recorded virtually no hits and only slowed down the scan.
|
||||
|
||||
ulong stepHigh = step.High;
|
||||
ulong stepLow = step.Low;
|
||||
ulong limitHigh = limit.High;
|
||||
|
||||
if (stepHigh == 0UL && limitHigh == 0UL)
|
||||
{
|
||||
ulong maxK = allowedMax > 0UL ? (allowedMax - 1UL) / stepLow : 0UL;
|
||||
if (maxK == 0UL)
|
||||
{
|
||||
processedAll = true;
|
||||
foundDivisor = 0UL;
|
||||
return false;
|
||||
}
|
||||
|
||||
ulong startK = minK < 1UL ? 1UL : minK;
|
||||
bool processedTop = true;
|
||||
bool processedBottom = true;
|
||||
bool composite = false;
|
||||
|
||||
if (startK <= maxK)
|
||||
{
|
||||
composite = CheckDivisors64Range(
|
||||
prime,
|
||||
stepLow,
|
||||
allowedMax,
|
||||
startK,
|
||||
maxK,
|
||||
ref currentK,
|
||||
out processedTop,
|
||||
out foundDivisor);
|
||||
if (composite)
|
||||
{
|
||||
processedAll = true;
|
||||
return true;
|
||||
}
|
||||
}
|
||||
|
||||
ulong lowerEnd = startK > 1UL ? startK - 1UL : 0UL;
|
||||
if (lowerEnd >= 1UL && startK == 1UL)
|
||||
{
|
||||
lowerEnd = Math.Min(lowerEnd, maxK);
|
||||
currentK = 1UL;
|
||||
composite = CheckDivisors64Range(
|
||||
prime,
|
||||
stepLow,
|
||||
allowedMax,
|
||||
1UL,
|
||||
lowerEnd,
|
||||
ref currentK,
|
||||
out processedBottom,
|
||||
out foundDivisor);
|
||||
}
|
||||
|
||||
processedAll = processedTop && processedBottom;
|
||||
return composite;
|
||||
}
|
||||
|
||||
PrimeOrderCalculatorAccelerator gpu = Accelerator;
|
||||
var residueStepper = new MersenneDivisorResidueStepper(prime, step, divisor);
|
||||
|
||||
while (divisor.CompareTo(limit) <= 0)
|
||||
{
|
||||
if (residueStepper.IsAdmissible())
|
||||
{
|
||||
ulong candidate = divisor.Low;
|
||||
MontgomeryDivisorData divisorData = MontgomeryDivisorData.FromModulus(candidate);
|
||||
ulong divisorCycle;
|
||||
// Divisors generated from 2 * k * p + 1 exceed the small-cycle snapshot when p >= 138,000,000, so the short path below never runs.
|
||||
if (!MersenneNumberDivisorByDivisorTester.TryCalculateCycleLengthForExponentHybrid(
|
||||
candidate,
|
||||
gpu,
|
||||
prime,
|
||||
divisorData,
|
||||
out ulong computedCycle,
|
||||
out bool primeOrderFailed) || computedCycle == 0UL)
|
||||
{
|
||||
// Divisors produced by 2 * k * p + 1 always exceed PerfectNumberConstants.MaxQForDivisorCycles
|
||||
// for the exponents scanned here, so skip the unused cache fallback and compute directly.
|
||||
divisorCycle = MersenneNumberDivisorByDivisorTester.CalculateCycleLengthHybrid(
|
||||
candidate,
|
||||
gpu,
|
||||
divisorData,
|
||||
skipPrimeOrderHeuristic: primeOrderFailed);
|
||||
}
|
||||
else
|
||||
{
|
||||
divisorCycle = computedCycle;
|
||||
}
|
||||
|
||||
RecordState(currentK);
|
||||
if (divisorCycle == prime)
|
||||
{
|
||||
// A cycle equal to the tested exponent (which is prime in this path) guarantees that the candidate divides
|
||||
// the corresponding Mersenne number because the order of 2 modulo the divisor is exactly p.
|
||||
foundDivisor = candidate;
|
||||
processedAll = true;
|
||||
return true;
|
||||
}
|
||||
|
||||
if (divisorCycle == 0UL)
|
||||
{
|
||||
Console.WriteLine($"Divisor cycle was not calculated for {prime}");
|
||||
}
|
||||
}
|
||||
|
||||
divisor.Add(step);
|
||||
currentK++;
|
||||
residueStepper.Advance();
|
||||
}
|
||||
|
||||
processedAll = true;
|
||||
foundDivisor = 0UL;
|
||||
return false;
|
||||
}
|
||||
|
||||
private bool CheckDivisorsLarge(
|
||||
ulong prime,
|
||||
BigInteger allowedMax,
|
||||
BigInteger minK,
|
||||
BigInteger step,
|
||||
out bool processedAll,
|
||||
out BigInteger foundDivisor)
|
||||
{
|
||||
processedAll = true;
|
||||
foundDivisor = BigInteger.Zero;
|
||||
BigInteger currentK = minK < BigInteger.One ? BigInteger.One : minK;
|
||||
BigInteger divisor = (step * currentK) + BigInteger.One;
|
||||
if (allowedMax.IsZero)
|
||||
{
|
||||
processedAll = false;
|
||||
return false;
|
||||
}
|
||||
if (divisor > allowedMax)
|
||||
{
|
||||
return false;
|
||||
}
|
||||
|
||||
LastDigit lastDigit = (prime & 3UL) == 3UL ? LastDigit.Seven : LastDigit.One;
|
||||
ushort decimalMask = DivisorGenerator.GetDecimalMask(lastDigit);
|
||||
|
||||
var rem10 = new BigIntegerCycleRemainderStepper(10);
|
||||
var rem8 = new BigIntegerCycleRemainderStepper(8);
|
||||
var rem5 = new BigIntegerCycleRemainderStepper(5);
|
||||
var rem3 = new BigIntegerCycleRemainderStepper(3);
|
||||
var rem7 = new BigIntegerCycleRemainderStepper(7);
|
||||
var rem11 = new BigIntegerCycleRemainderStepper(11);
|
||||
var rem13 = new BigIntegerCycleRemainderStepper(13);
|
||||
var rem17 = new BigIntegerCycleRemainderStepper(17);
|
||||
var rem19 = new BigIntegerCycleRemainderStepper(19);
|
||||
|
||||
byte remainder10 = (byte)rem10.Initialize(divisor);
|
||||
byte remainder8 = (byte)rem8.Initialize(divisor);
|
||||
byte remainder5 = (byte)rem5.Initialize(divisor);
|
||||
byte remainder3 = (byte)rem3.Initialize(divisor);
|
||||
byte remainder7 = (byte)rem7.Initialize(divisor);
|
||||
byte remainder11 = (byte)rem11.Initialize(divisor);
|
||||
byte remainder13 = (byte)rem13.Initialize(divisor);
|
||||
byte remainder17 = (byte)rem17.Initialize(divisor);
|
||||
byte remainder19 = (byte)rem19.Initialize(divisor);
|
||||
|
||||
while (divisor <= allowedMax)
|
||||
{
|
||||
bool passesSmallModuli = remainder3 != 0 && remainder5 != 0 && remainder7 != 0 && remainder11 != 0 && remainder13 != 0 && remainder17 != 0 && remainder19 != 0;
|
||||
if (passesSmallModuli && (remainder8 == 1 || remainder8 == 7) && ((decimalMask >> remainder10) & 1) != 0)
|
||||
{
|
||||
if (MersenneNumberDivisorByDivisorTester.IsProbablePrimeBigInteger(divisor))
|
||||
{
|
||||
BigInteger powResult = BigInteger.ModPow(2, prime, divisor);
|
||||
RecordState(currentK);
|
||||
if (powResult.IsOne)
|
||||
{
|
||||
foundDivisor = divisor;
|
||||
processedAll = true;
|
||||
return true;
|
||||
}
|
||||
}
|
||||
else
|
||||
{
|
||||
RecordState(currentK);
|
||||
}
|
||||
}
|
||||
|
||||
currentK += BigInteger.One;
|
||||
divisor += step;
|
||||
remainder10 = (byte)rem10.ComputeNext(divisor);
|
||||
remainder8 = (byte)rem8.ComputeNext(divisor);
|
||||
remainder5 = (byte)rem5.ComputeNext(divisor);
|
||||
remainder3 = (byte)rem3.ComputeNext(divisor);
|
||||
remainder7 = (byte)rem7.ComputeNext(divisor);
|
||||
remainder11 = (byte)rem11.ComputeNext(divisor);
|
||||
remainder13 = (byte)rem13.ComputeNext(divisor);
|
||||
remainder17 = (byte)rem17.ComputeNext(divisor);
|
||||
remainder19 = (byte)rem19.ComputeNext(divisor);
|
||||
|
||||
if (divisor > allowedMax)
|
||||
{
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
processedAll = true;
|
||||
foundDivisor = BigInteger.Zero;
|
||||
return false;
|
||||
}
|
||||
|
||||
private bool CheckDivisors64Range(
|
||||
ulong prime,
|
||||
ulong step,
|
||||
ulong allowedMax,
|
||||
ulong startK,
|
||||
ulong endK,
|
||||
ref ulong currentK,
|
||||
out bool processedAll,
|
||||
out ulong foundDivisor)
|
||||
{
|
||||
if (startK < 1UL || endK < startK)
|
||||
{
|
||||
processedAll = true;
|
||||
foundDivisor = 0UL;
|
||||
return false;
|
||||
}
|
||||
currentK = startK;
|
||||
|
||||
UInt128 step128 = step;
|
||||
UInt128 allowedMax128 = allowedMax;
|
||||
UInt128 startDivisor128 = (step128 * startK) + UInt128.One;
|
||||
if (startDivisor128 > allowedMax128)
|
||||
{
|
||||
processedAll = true;
|
||||
foundDivisor = 0UL;
|
||||
return false;
|
||||
}
|
||||
|
||||
UInt128 rangeLimit128 = (step128 * endK) + UInt128.One;
|
||||
if (rangeLimit128 > allowedMax128)
|
||||
{
|
||||
rangeLimit128 = allowedMax128;
|
||||
}
|
||||
|
||||
ulong startDivisor = (ulong)startDivisor128;
|
||||
ulong rangeLimit = (ulong)rangeLimit128;
|
||||
|
||||
var residueStepper = new MersenneDivisorResidueStepper(prime, (GpuUInt128)step128, (GpuUInt128)startDivisor128);
|
||||
|
||||
return CheckDivisors64(
|
||||
prime,
|
||||
step,
|
||||
rangeLimit,
|
||||
startDivisor,
|
||||
ref residueStepper,
|
||||
ref currentK,
|
||||
out processedAll,
|
||||
out foundDivisor);
|
||||
}
|
||||
|
||||
private bool CheckDivisors64(
|
||||
ulong prime,
|
||||
ulong step,
|
||||
ulong limit,
|
||||
ulong divisor,
|
||||
ref MersenneDivisorResidueStepper residueStepper,
|
||||
ref ulong currentK,
|
||||
out bool processedAll,
|
||||
out ulong foundDivisor)
|
||||
{
|
||||
PrimeOrderCalculatorAccelerator gpu = Accelerator;
|
||||
bool canAdvance = step <= limit;
|
||||
if (!canAdvance)
|
||||
{
|
||||
if (divisor <= limit && residueStepper.IsAdmissible())
|
||||
{
|
||||
MontgomeryDivisorData divisorData = MontgomeryDivisorData.FromModulus(divisor);
|
||||
ulong divisorCycle;
|
||||
if (!MersenneNumberDivisorByDivisorTester.TryCalculateCycleLengthForExponentHybrid(
|
||||
divisor,
|
||||
gpu,
|
||||
prime,
|
||||
divisorData,
|
||||
out ulong computedCycle,
|
||||
out bool primeOrderFailed) || computedCycle == 0UL)
|
||||
{
|
||||
divisorCycle = MersenneNumberDivisorByDivisorTester.CalculateCycleLengthHybrid(
|
||||
divisor,
|
||||
gpu,
|
||||
divisorData,
|
||||
skipPrimeOrderHeuristic: primeOrderFailed);
|
||||
}
|
||||
else
|
||||
{
|
||||
divisorCycle = computedCycle;
|
||||
}
|
||||
|
||||
if (divisorCycle == prime)
|
||||
{
|
||||
foundDivisor = divisor;
|
||||
processedAll = true;
|
||||
return true;
|
||||
}
|
||||
|
||||
if (divisorCycle == 0UL)
|
||||
{
|
||||
Console.WriteLine($"Divisor cycle was not calculated for {prime}");
|
||||
}
|
||||
}
|
||||
|
||||
processedAll = true;
|
||||
foundDivisor = 0UL;
|
||||
return false;
|
||||
}
|
||||
|
||||
if (divisor > limit)
|
||||
{
|
||||
processedAll = true;
|
||||
foundDivisor = 0UL;
|
||||
return false;
|
||||
}
|
||||
|
||||
ulong remainingIterations = ((limit - divisor) / step) + 1UL;
|
||||
while (true)
|
||||
{
|
||||
if (residueStepper.IsAdmissible())
|
||||
{
|
||||
MontgomeryDivisorData divisorData = MontgomeryDivisorData.FromModulus(divisor);
|
||||
ulong divisorCycle;
|
||||
if (!MersenneNumberDivisorByDivisorTester.TryCalculateCycleLengthForExponentHybrid(
|
||||
divisor,
|
||||
gpu,
|
||||
prime,
|
||||
divisorData,
|
||||
out ulong computedCycle,
|
||||
out bool primeOrderFailed) || computedCycle == 0UL)
|
||||
{
|
||||
divisorCycle = MersenneNumberDivisorByDivisorTester.CalculateCycleLengthHybrid(
|
||||
divisor,
|
||||
gpu,
|
||||
divisorData,
|
||||
skipPrimeOrderHeuristic: primeOrderFailed);
|
||||
}
|
||||
else
|
||||
{
|
||||
divisorCycle = computedCycle;
|
||||
}
|
||||
|
||||
RecordState(currentK);
|
||||
if (divisorCycle == prime)
|
||||
{
|
||||
foundDivisor = divisor;
|
||||
processedAll = true;
|
||||
return true;
|
||||
}
|
||||
|
||||
if (divisorCycle == 0UL)
|
||||
{
|
||||
Console.WriteLine($"Divisor cycle was not calculated for {prime}");
|
||||
}
|
||||
}
|
||||
|
||||
remainingIterations--;
|
||||
if (remainingIterations == 0UL)
|
||||
{
|
||||
processedAll = true;
|
||||
foundDivisor = 0UL;
|
||||
return false;
|
||||
}
|
||||
|
||||
divisor += step;
|
||||
currentK++;
|
||||
residueStepper.Advance();
|
||||
}
|
||||
}
|
||||
|
||||
private void RecordState(BigInteger k)
|
||||
{
|
||||
string path = StateFilePath;
|
||||
|
||||
if (k <= _lastSavedK)
|
||||
{
|
||||
return;
|
||||
}
|
||||
|
||||
int next = _stateCounter + 1;
|
||||
if (next >= PerfectNumberConstants.ByDivisorStateSaveInterval)
|
||||
{
|
||||
string? directory = Path.GetDirectoryName(path);
|
||||
if (!string.IsNullOrEmpty(directory))
|
||||
{
|
||||
Directory.CreateDirectory(directory);
|
||||
}
|
||||
|
||||
File.AppendAllText(path, k.ToString(CultureInfo.InvariantCulture) + Environment.NewLine);
|
||||
_stateCounter = 0;
|
||||
_lastSavedK = k;
|
||||
}
|
||||
else
|
||||
{
|
||||
_stateCounter = next;
|
||||
}
|
||||
}
|
||||
}
|
||||
@@ -0,0 +1,88 @@
|
||||
using System.Globalization;
|
||||
using System.Numerics;
|
||||
using PerfectNumbers.Core.Gpu;
|
||||
|
||||
namespace PerfectNumbers.Core.Cpu;
|
||||
|
||||
internal struct MersenneNumberDivisorByDivisorPrimeScanSessionWithCpuOrder(
|
||||
in MersenneNumberDivisorByDivisorCpuTesterWithCpuOrder prototype,
|
||||
Action markComposite,
|
||||
Action clearComposite,
|
||||
Action<ulong, bool, bool, bool, BigInteger> printResult)
|
||||
{
|
||||
private MersenneNumberDivisorByDivisorCpuTesterWithCpuOrder _tester = new()
|
||||
{
|
||||
DivisorLimit = prototype.DivisorLimit,
|
||||
MinK = EnvironmentConfiguration.MinK,
|
||||
};
|
||||
|
||||
private MersenneCpuDivisorScanSessionWithCpuOrder _divisorScanSession = new();
|
||||
|
||||
private readonly Action _markComposite = markComposite;
|
||||
private readonly Action _clearComposite = clearComposite;
|
||||
private readonly Action<ulong, bool, bool, bool, BigInteger> _printResult = printResult;
|
||||
|
||||
public void ProcessPrime(ulong prime)
|
||||
{
|
||||
try
|
||||
{
|
||||
Console.WriteLine($"Processing {prime}");
|
||||
string stateFile = Path.Combine(
|
||||
PerfectNumberConstants.ByDivisorStateDirectory,
|
||||
prime.ToString(CultureInfo.InvariantCulture) + ".bin");
|
||||
|
||||
ConfigureForPrime(stateFile);
|
||||
|
||||
bool isPrime = _tester.IsPrime(prime, out bool divisorsExhausted, out BigInteger divisor);
|
||||
|
||||
if (!isPrime)
|
||||
{
|
||||
if (!string.IsNullOrEmpty(stateFile) && File.Exists(stateFile))
|
||||
{
|
||||
File.Delete(stateFile);
|
||||
}
|
||||
|
||||
_markComposite();
|
||||
_printResult(prime, true, true, false, divisor);
|
||||
Console.WriteLine($"Finished processing {prime}");
|
||||
return;
|
||||
}
|
||||
|
||||
_clearComposite();
|
||||
_printResult(prime, true, divisorsExhausted, true, divisor);
|
||||
Console.WriteLine($"Finished processing {prime}");
|
||||
}
|
||||
catch (Exception ex)
|
||||
{
|
||||
Console.WriteLine($"Error processing {ex.Message} {ex.StackTrace}");
|
||||
Environment.Exit(1);
|
||||
}
|
||||
}
|
||||
|
||||
private void ConfigureForPrime(string stateFile)
|
||||
{
|
||||
BigInteger resumeK = EnvironmentConfiguration.MinK;
|
||||
if (File.Exists(stateFile))
|
||||
{
|
||||
if (MersenneNumberDivisorByDivisorTester.TryReadLastSavedK(stateFile, out BigInteger lastK))
|
||||
{
|
||||
resumeK = lastK + BigInteger.One;
|
||||
_tester.ResumeFromState(stateFile, lastK, resumeK);
|
||||
}
|
||||
else
|
||||
{
|
||||
_tester.ResumeFromState(stateFile, BigInteger.Zero, resumeK);
|
||||
}
|
||||
}
|
||||
else
|
||||
{
|
||||
_tester.ResumeFromState(stateFile, BigInteger.Zero, resumeK);
|
||||
}
|
||||
|
||||
_tester.ResetStateTracking();
|
||||
}
|
||||
|
||||
public void Dispose()
|
||||
{
|
||||
}
|
||||
}
|
||||
+101
@@ -0,0 +1,101 @@
|
||||
using System.Globalization;
|
||||
using System.Numerics;
|
||||
using PerfectNumbers.Core.Gpu;
|
||||
using PerfectNumbers.Core.Gpu.Accelerators;
|
||||
|
||||
namespace PerfectNumbers.Core.Cpu;
|
||||
|
||||
internal struct MersenneNumberDivisorByDivisorPrimeScanSessionWithGpuOrder
|
||||
{
|
||||
private MersenneNumberDivisorByDivisorCpuTesterWithGpuOrder _tester;
|
||||
private MersenneCpuDivisorScanSessionWithGpuOrder _divisorScanSession;
|
||||
|
||||
private readonly Action _markComposite;
|
||||
private readonly Action _clearComposite;
|
||||
private readonly Action<ulong, bool, bool, bool, BigInteger> _printResult;
|
||||
|
||||
public MersenneNumberDivisorByDivisorPrimeScanSessionWithGpuOrder(
|
||||
in MersenneNumberDivisorByDivisorCpuTesterWithGpuOrder prototype,
|
||||
Action markComposite,
|
||||
Action clearComposite,
|
||||
Action<ulong, bool, bool, bool, BigInteger> printResult)
|
||||
{
|
||||
_tester = new MersenneNumberDivisorByDivisorCpuTesterWithGpuOrder
|
||||
{
|
||||
DivisorLimit = prototype.DivisorLimit,
|
||||
MinK = EnvironmentConfiguration.MinK,
|
||||
};
|
||||
|
||||
_divisorScanSession = new MersenneCpuDivisorScanSessionWithGpuOrder();
|
||||
_divisorScanSession.Configure(_tester.Accelerator);
|
||||
|
||||
_markComposite = markComposite;
|
||||
_clearComposite = clearComposite;
|
||||
_printResult = printResult;
|
||||
}
|
||||
|
||||
public void ProcessPrime(ulong prime)
|
||||
{
|
||||
try
|
||||
{
|
||||
Console.WriteLine($"Processing {prime}");
|
||||
string stateFile = Path.Combine(
|
||||
PerfectNumberConstants.ByDivisorStateDirectory,
|
||||
prime.ToString(CultureInfo.InvariantCulture) + ".bin");
|
||||
|
||||
ConfigureForPrime(stateFile);
|
||||
|
||||
bool isPrime = _tester.IsPrime(prime, out bool divisorsExhausted, out BigInteger divisor);
|
||||
|
||||
if (!isPrime)
|
||||
{
|
||||
if (!string.IsNullOrEmpty(stateFile) && File.Exists(stateFile))
|
||||
{
|
||||
File.Delete(stateFile);
|
||||
}
|
||||
|
||||
_markComposite();
|
||||
_printResult(prime, true, true, false, divisor);
|
||||
Console.WriteLine($"Finished processing {prime}");
|
||||
return;
|
||||
}
|
||||
|
||||
_clearComposite();
|
||||
_printResult(prime, true, divisorsExhausted, true, divisor);
|
||||
Console.WriteLine($"Finished processing {prime}");
|
||||
}
|
||||
catch (Exception ex)
|
||||
{
|
||||
Console.WriteLine($"Error processing {ex.Message} {ex.StackTrace}");
|
||||
Environment.Exit(1);
|
||||
}
|
||||
}
|
||||
|
||||
private void ConfigureForPrime(string stateFile)
|
||||
{
|
||||
BigInteger resumeK = EnvironmentConfiguration.MinK;
|
||||
if (File.Exists(stateFile))
|
||||
{
|
||||
if (MersenneNumberDivisorByDivisorTester.TryReadLastSavedK(stateFile, out BigInteger lastK))
|
||||
{
|
||||
resumeK = lastK + BigInteger.One;
|
||||
_tester.ResumeFromState(stateFile, lastK, resumeK);
|
||||
}
|
||||
else
|
||||
{
|
||||
_tester.ResumeFromState(stateFile, BigInteger.Zero, resumeK);
|
||||
}
|
||||
}
|
||||
else
|
||||
{
|
||||
_tester.ResumeFromState(stateFile, BigInteger.Zero, resumeK);
|
||||
}
|
||||
|
||||
_tester.ResetStateTracking();
|
||||
}
|
||||
|
||||
public void Dispose()
|
||||
{
|
||||
PrimeOrderCalculatorAccelerator.Return(_tester.Accelerator);
|
||||
}
|
||||
}
|
||||
+101
@@ -0,0 +1,101 @@
|
||||
using System.Globalization;
|
||||
using System.Numerics;
|
||||
using PerfectNumbers.Core.Gpu;
|
||||
using PerfectNumbers.Core.Gpu.Accelerators;
|
||||
|
||||
namespace PerfectNumbers.Core.Cpu;
|
||||
|
||||
internal struct MersenneNumberDivisorByDivisorPrimeScanSessionWithHybridOrder
|
||||
{
|
||||
private MersenneNumberDivisorByDivisorCpuTesterWithHybridOrder _tester;
|
||||
private MersenneCpuDivisorScanSessionWithHybridOrder _divisorScanSession;
|
||||
|
||||
private readonly Action _markComposite;
|
||||
private readonly Action _clearComposite;
|
||||
private readonly Action<ulong, bool, bool, bool, BigInteger> _printResult;
|
||||
|
||||
public MersenneNumberDivisorByDivisorPrimeScanSessionWithHybridOrder(
|
||||
in MersenneNumberDivisorByDivisorCpuTesterWithHybridOrder prototype,
|
||||
Action markComposite,
|
||||
Action clearComposite,
|
||||
Action<ulong, bool, bool, bool, BigInteger> printResult)
|
||||
{
|
||||
_tester = new MersenneNumberDivisorByDivisorCpuTesterWithHybridOrder
|
||||
{
|
||||
DivisorLimit = prototype.DivisorLimit,
|
||||
MinK = EnvironmentConfiguration.MinK,
|
||||
};
|
||||
|
||||
_divisorScanSession = new MersenneCpuDivisorScanSessionWithHybridOrder();
|
||||
_divisorScanSession.Configure(_tester.Accelerator);
|
||||
|
||||
_markComposite = markComposite;
|
||||
_clearComposite = clearComposite;
|
||||
_printResult = printResult;
|
||||
}
|
||||
|
||||
public void ProcessPrime(ulong prime)
|
||||
{
|
||||
try
|
||||
{
|
||||
Console.WriteLine($"Processing {prime}");
|
||||
string stateFile = Path.Combine(
|
||||
PerfectNumberConstants.ByDivisorStateDirectory,
|
||||
prime.ToString(CultureInfo.InvariantCulture) + ".bin");
|
||||
|
||||
ConfigureForPrime(stateFile);
|
||||
|
||||
bool isPrime = _tester.IsPrime(prime, out bool divisorsExhausted, out BigInteger divisor);
|
||||
|
||||
if (!isPrime)
|
||||
{
|
||||
if (!string.IsNullOrEmpty(stateFile) && File.Exists(stateFile))
|
||||
{
|
||||
File.Delete(stateFile);
|
||||
}
|
||||
|
||||
_markComposite();
|
||||
_printResult(prime, true, true, false, divisor);
|
||||
Console.WriteLine($"Finished processing {prime}");
|
||||
return;
|
||||
}
|
||||
|
||||
_clearComposite();
|
||||
_printResult(prime, true, divisorsExhausted, true, divisor);
|
||||
Console.WriteLine($"Finished processing {prime}");
|
||||
}
|
||||
catch (Exception ex)
|
||||
{
|
||||
Console.WriteLine($"Error processing {ex.Message} {ex.StackTrace}");
|
||||
Environment.Exit(1);
|
||||
}
|
||||
}
|
||||
|
||||
private void ConfigureForPrime(string stateFile)
|
||||
{
|
||||
BigInteger resumeK = EnvironmentConfiguration.MinK;
|
||||
if (File.Exists(stateFile))
|
||||
{
|
||||
if (MersenneNumberDivisorByDivisorTester.TryReadLastSavedK(stateFile, out BigInteger lastK))
|
||||
{
|
||||
resumeK = lastK + BigInteger.One;
|
||||
_tester.ResumeFromState(stateFile, lastK, resumeK);
|
||||
}
|
||||
else
|
||||
{
|
||||
_tester.ResumeFromState(stateFile, BigInteger.Zero, resumeK);
|
||||
}
|
||||
}
|
||||
else
|
||||
{
|
||||
_tester.ResumeFromState(stateFile, BigInteger.Zero, resumeK);
|
||||
}
|
||||
|
||||
_tester.ResetStateTracking();
|
||||
}
|
||||
|
||||
public void Dispose()
|
||||
{
|
||||
PrimeOrderCalculatorAccelerator.Return(_tester.Accelerator);
|
||||
}
|
||||
}
|
||||
Reference in new issue
Block a user