Files
even-perfect-numbers-scanner/PerfectNumbers.Core/Gpu/MersenneNumberDivisorByDivisorGpuTester.cs
T

927 lines
32 KiB
C#

using System;
using System.Buffers;
using System.Collections.Concurrent;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;
using System.Numerics;
using ILGPU;
using ILGPU.Runtime;
using MontgomeryDivisorData = PerfectNumbers.Core.MontgomeryDivisorData;
using MontgomeryDivisorDataCache = PerfectNumbers.Core.MontgomeryDivisorDataCache;
using CycleRemainderStepper = PerfectNumbers.Core.CycleRemainderStepper;
namespace PerfectNumbers.Core.Gpu;
public sealed class MersenneNumberDivisorByDivisorGpuTester : IMersenneNumberDivisorByDivisorTester
{
private int _gpuBatchSize = GpuConstants.ScanBatchSize;
private readonly object _sync = new();
private ulong _divisorLimit;
private bool _isConfigured;
private bool _useDivisorCycles;
private readonly ConcurrentDictionary<Accelerator, Action<Index1D, ArrayView<MontgomeryDivisorData>, ArrayView<ulong>, ArrayView<byte>>> _kernelCache = new();
private readonly ConcurrentDictionary<Accelerator, Action<Index1D, MontgomeryDivisorData, ArrayView<ulong>, ArrayView<ulong>>> _kernelExponentCache = new();
private readonly ConcurrentDictionary<Accelerator, ConcurrentBag<BatchResources>> _resourcePools = new(AcceleratorReferenceComparer.Instance);
private readonly ConcurrentBag<DivisorScanSession> _sessionPool = new();
private Action<Index1D, ArrayView<MontgomeryDivisorData>, ArrayView<ulong>, ArrayView<byte>> GetKernel(Accelerator accelerator) =>
_kernelCache.GetOrAdd(accelerator, acc => acc.LoadAutoGroupedStreamKernel<Index1D, ArrayView<MontgomeryDivisorData>, ArrayView<ulong>, ArrayView<byte>>(CheckKernel));
private Action<Index1D, MontgomeryDivisorData, ArrayView<ulong>, ArrayView<ulong>> GetKernelByPrimeExponent(Accelerator accelerator) =>
_kernelExponentCache.GetOrAdd(accelerator, acc => acc.LoadAutoGroupedStreamKernel<Index1D, MontgomeryDivisorData, ArrayView<ulong>, ArrayView<ulong>>(ComputeMontgomeryExponentKernel));
public int GpuBatchSize
{
get => _gpuBatchSize;
set => _gpuBatchSize = Math.Max(1, value);
}
int IMersenneNumberDivisorByDivisorTester.BatchSize
{
get => GpuBatchSize;
set => GpuBatchSize = value;
}
public bool UseDivisorCycles
{
get => _useDivisorCycles;
set => _useDivisorCycles = value;
}
public void ConfigureFromMaxPrime(ulong maxPrime)
{
lock (_sync)
{
_divisorLimit = ComputeDivisorLimitFromMaxPrime(maxPrime);
_isConfigured = true;
}
}
public bool IsPrime(ulong prime, out bool divisorsExhausted)
{
ulong allowedMax;
bool useCycles;
int batchCapacity;
lock (_sync)
{
if (!_isConfigured)
{
throw new InvalidOperationException("ConfigureFromMaxPrime must be called before using the tester.");
}
allowedMax = ComputeAllowedMaxDivisor(prime, _divisorLimit);
useCycles = _useDivisorCycles;
batchCapacity = _gpuBatchSize;
}
if (allowedMax < 3UL)
{
divisorsExhausted = true;
return true;
}
bool composite;
bool coveredRange;
ulong processedCount;
ulong lastProcessed;
var gpuLease = GpuContextPool.RentPreferred(preferCpu: false);
var accelerator = gpuLease.Accelerator;
var kernel = GetKernel(accelerator);
BatchResources resources = RentBatchResources(accelerator, batchCapacity);
try
{
composite = CheckDivisors(
prime,
allowedMax,
useCycles,
accelerator,
kernel,
resources.DivisorsBuffer,
resources.ExponentBuffer,
resources.HitsBuffer,
resources.Divisors,
resources.Exponents,
resources.Hits,
resources.DivisorData,
out lastProcessed,
out coveredRange,
out processedCount
);
}
finally
{
ReturnBatchResources(accelerator, resources);
gpuLease.Dispose();
}
if (composite)
{
divisorsExhausted = true;
return false;
}
divisorsExhausted = coveredRange;
return true;
}
private static bool CheckDivisors(
ulong prime,
ulong allowedMax,
bool useCycles,
Accelerator accelerator,
Action<Index1D, ArrayView<MontgomeryDivisorData>, ArrayView<ulong>, ArrayView<byte>> kernel,
MemoryBuffer1D<MontgomeryDivisorData, Stride1D.Dense> divisorsBuffer,
MemoryBuffer1D<ulong, Stride1D.Dense> exponentBuffer,
MemoryBuffer1D<byte, Stride1D.Dense> hitsBuffer,
in ulong[] divisors,
ulong[] exponents,
byte[] hits,
MontgomeryDivisorData[] divisorData,
out ulong lastProcessed,
out bool coveredRange,
out ulong processedCount)
{
lastProcessed = 0UL;
processedCount = 0UL;
if (allowedMax < 3UL)
{
coveredRange = true;
return false;
}
return useCycles
? CheckDivisorsWithCycles(
prime,
allowedMax,
accelerator,
kernel,
divisorsBuffer,
exponentBuffer,
hitsBuffer,
divisors,
exponents,
hits,
divisorData,
ref lastProcessed,
ref processedCount,
out coveredRange)
: CheckDivisorsWithoutCycles(
prime,
allowedMax,
accelerator,
kernel,
divisorsBuffer,
exponentBuffer,
hitsBuffer,
divisors,
exponents,
hits,
divisorData,
ref lastProcessed,
ref processedCount,
out coveredRange);
}
private static bool CheckDivisorsWithoutCycles(
ulong prime,
ulong allowedMax,
Accelerator accelerator,
Action<Index1D, ArrayView<MontgomeryDivisorData>, ArrayView<ulong>, ArrayView<byte>> kernel,
MemoryBuffer1D<MontgomeryDivisorData, Stride1D.Dense> divisorsBuffer,
MemoryBuffer1D<ulong, Stride1D.Dense> exponentBuffer,
MemoryBuffer1D<byte, Stride1D.Dense> hitsBuffer,
in ulong[] divisors,
ulong[] exponents,
byte[] hits,
MontgomeryDivisorData[] divisorData,
ref ulong lastProcessed,
ref ulong processedCount,
out bool coveredRange)
{
int batchCapacity = (int)divisorsBuffer.Length;
bool composite = false;
bool processedAll = false;
ulong currentDivisor = 3UL;
Span<MontgomeryDivisorData> divisorDataSpan;
Span<ulong> divisorSpan;
Span<ulong> exponentSpan;
Span<byte> hitsSpan;
ArrayView1D<MontgomeryDivisorData, Stride1D.Dense> divisorView;
ArrayView1D<ulong, Stride1D.Dense> exponentView;
ArrayView1D<byte, Stride1D.Dense> hitsView;
while (currentDivisor <= allowedMax)
{
int batchSize = 0;
bool reachedEndInBatch = false;
// The GPU buffers are sized exactly to the configured batch capacity, so we
// must stop once the current batch is full to avoid writing past the spans.
while (batchSize < batchCapacity && currentDivisor <= allowedMax)
{
ulong nextDivisor = currentDivisor + 2UL;
processedCount++;
divisors[batchSize] = currentDivisor;
exponents[batchSize] = prime;
batchSize++;
lastProcessed = currentDivisor;
if (nextDivisor <= currentDivisor)
{
reachedEndInBatch = true;
break;
}
if (nextDivisor > allowedMax)
{
currentDivisor = nextDivisor;
reachedEndInBatch = true;
break;
}
currentDivisor = nextDivisor;
}
if (batchSize == 0)
{
if (reachedEndInBatch)
{
processedAll = true;
break;
}
continue;
}
divisorDataSpan = divisorData.AsSpan(0, batchSize);
divisorSpan = divisors.AsSpan(0, batchSize);
exponentSpan = exponents.AsSpan(0, batchSize);
hitsSpan = hits.AsSpan(0, batchSize);
divisorView = divisorsBuffer.View.SubView(0, batchSize);
exponentView = exponentBuffer.View.SubView(0, batchSize);
hitsView = hitsBuffer.View.SubView(0, batchSize);
for (int i = 0; i < batchSize; i++)
{
divisorDataSpan[i] = MontgomeryDivisorDataCache.Get(divisorSpan[i]);
}
divisorView.CopyFromCPU(ref MemoryMarshal.GetReference(divisorDataSpan), batchSize);
exponentView.CopyFromCPU(ref MemoryMarshal.GetReference(exponentSpan), batchSize);
kernel(batchSize, divisorView, exponentView, hitsView);
hitsView.CopyToCPU(ref MemoryMarshal.GetReference(hitsSpan), batchSize);
for (int i = 0; i < batchSize; i++)
{
if (hitsSpan[i] != 0)
{
composite = true;
lastProcessed = divisorSpan[i];
break;
}
}
if (!composite)
{
lastProcessed = divisorSpan[batchSize - 1];
}
if (composite)
{
break;
}
if (reachedEndInBatch)
{
processedAll = true;
break;
}
}
coveredRange = composite || processedAll || currentDivisor > allowedMax;
return composite;
}
private static bool CheckDivisorsWithCycles(
ulong prime,
ulong allowedMax,
Accelerator accelerator,
Action<Index1D, ArrayView<MontgomeryDivisorData>, ArrayView<ulong>, ArrayView<byte>> kernel,
MemoryBuffer1D<MontgomeryDivisorData, Stride1D.Dense> divisorsBuffer,
MemoryBuffer1D<ulong, Stride1D.Dense> exponentBuffer,
MemoryBuffer1D<byte, Stride1D.Dense> hitsBuffer,
in ulong[] divisors,
ulong[] exponents,
byte[] hits,
MontgomeryDivisorData[] divisorData,
ref ulong lastProcessed,
ref ulong processedCount,
out bool coveredRange)
{
int batchCapacity = (int)divisorsBuffer.Length;
bool composite = false;
bool processedAll = false;
ulong currentDivisor = 3UL;
ulong cycleLeaseEnd;
Span<MontgomeryDivisorData> divisorDataSpan;
Span<ulong> divisorSpan;
Span<ulong> exponentSpan;
Span<byte> hitsSpan;
ArrayView1D<MontgomeryDivisorData, Stride1D.Dense> divisorView;
ArrayView1D<ulong, Stride1D.Dense> exponentView;
ArrayView1D<byte, Stride1D.Dense> hitsView;
DivisorCycleCache divisorCyclesCache = DivisorCycleCache.Shared;
DivisorCycleCache.CycleBlock cycleLease = divisorCyclesCache.Acquire(currentDivisor);
cycleLeaseEnd = cycleLease.End;
try
{
while (currentDivisor <= allowedMax)
{
int batchSize = 0;
bool reachedEndInBatch = false;
// Batch writes share the same buffers as the kernel launch, so we guard
// against exceeding the rented capacity on each iteration.
while (batchSize < batchCapacity && currentDivisor <= allowedMax)
{
ulong nextDivisor = currentDivisor + 2UL;
processedCount++;
if (currentDivisor > cycleLeaseEnd)
{
cycleLease.Dispose();
cycleLease = divisorCyclesCache.Acquire(currentDivisor);
cycleLeaseEnd = cycleLease.End;
}
bool includeDivisor = true;
ulong exponent = prime;
ulong cycleLength = cycleLease.GetCycle(currentDivisor);
if (cycleLength > 0UL)
{
ulong remainder = prime;
if (remainder >= cycleLength)
{
remainder %= cycleLength;
}
if (remainder != 0UL)
{
includeDivisor = false;
}
else
{
exponent = 0UL;
}
}
if (includeDivisor)
{
divisors[batchSize] = currentDivisor;
exponents[batchSize] = exponent;
batchSize++;
}
lastProcessed = currentDivisor;
if (nextDivisor <= currentDivisor)
{
reachedEndInBatch = true;
break;
}
if (nextDivisor > allowedMax)
{
currentDivisor = nextDivisor;
reachedEndInBatch = true;
break;
}
currentDivisor = nextDivisor;
}
if (batchSize == 0)
{
if (reachedEndInBatch)
{
processedAll = true;
break;
}
continue;
}
divisorDataSpan = divisorData.AsSpan(0, batchSize);
divisorSpan = divisors.AsSpan(0, batchSize);
exponentSpan = exponents.AsSpan(0, batchSize);
hitsSpan = hits.AsSpan(0, batchSize);
divisorView = divisorsBuffer.View.SubView(0, batchSize);
exponentView = exponentBuffer.View.SubView(0, batchSize);
hitsView = hitsBuffer.View.SubView(0, batchSize);
for (int i = 0; i < batchSize; i++)
{
divisorDataSpan[i] = MontgomeryDivisorDataCache.Get(divisorSpan[i]);
}
divisorView.CopyFromCPU(ref MemoryMarshal.GetReference(divisorDataSpan), batchSize);
exponentView.CopyFromCPU(ref MemoryMarshal.GetReference(exponentSpan), batchSize);
kernel(batchSize, divisorView, exponentView, hitsView);
hitsView.CopyToCPU(ref MemoryMarshal.GetReference(hitsSpan), batchSize);
for (int i = 0; i < batchSize; i++)
{
if (hitsSpan[i] != 0)
{
composite = true;
lastProcessed = divisorSpan[i];
break;
}
}
if (!composite)
{
lastProcessed = divisorSpan[batchSize - 1];
}
if (composite)
{
break;
}
if (reachedEndInBatch)
{
processedAll = true;
break;
}
}
}
finally
{
cycleLease.Dispose();
}
coveredRange = composite || processedAll || currentDivisor > allowedMax;
return composite;
}
private static ulong ComputeDivisorLimitFromMaxPrime(ulong maxPrime)
{
if (maxPrime <= 1UL)
{
return 0UL;
}
if (maxPrime - 1UL >= 64UL)
{
return ulong.MaxValue;
}
return (1UL << (int)(maxPrime - 1UL)) - 1UL;
}
private static ulong ComputeAllowedMaxDivisor(ulong prime, ulong divisorLimit)
{
if (prime <= 1UL)
{
return 0UL;
}
if (prime - 1UL >= 64UL)
{
return divisorLimit;
}
return Math.Min((1UL << (int)(prime - 1UL)) - 1UL, divisorLimit);
}
private static void CheckKernel(Index1D index, ArrayView<MontgomeryDivisorData> divisors, ArrayView<ulong> exponents, ArrayView<byte> hits)
{
MontgomeryDivisorData divisor = divisors[index];
ulong modulus = divisor.Modulus;
if (modulus <= 1UL || (modulus & 1UL) == 0UL)
{
hits[index] = 0;
return;
}
ulong exponent = exponents[index];
hits[index] = exponent.Pow2MontgomeryMod(divisor) == 1UL ? (byte)1 : (byte)0;
}
public sealed class DivisorScanSession : IMersenneNumberDivisorByDivisorTester.IDivisorScanSession
{
private readonly MersenneNumberDivisorByDivisorGpuTester _owner;
private readonly GpuContextPool.GpuContextLease _lease;
private readonly Accelerator _accelerator;
private readonly Action<Index1D, MontgomeryDivisorData, ArrayView<ulong>, ArrayView<ulong>> _kernel;
private MemoryBuffer1D<ulong, Stride1D.Dense> _exponentsBuffer;
private MemoryBuffer1D<ulong, Stride1D.Dense> _resultsBuffer;
private ulong[] _hostBuffer;
private int[]? _positionBuffer;
private int _capacity;
private bool _disposed;
internal DivisorScanSession(MersenneNumberDivisorByDivisorGpuTester owner)
{
_owner = owner;
_lease = GpuContextPool.RentPreferred(preferCpu: false);
_accelerator = _lease.Accelerator;
_kernel = owner.GetKernelByPrimeExponent(_accelerator);
_capacity = Math.Max(1, owner._gpuBatchSize);
_exponentsBuffer = _accelerator.Allocate1D<ulong>(_capacity);
_resultsBuffer = _accelerator.Allocate1D<ulong>(_capacity);
_hostBuffer = ArrayPool<ulong>.Shared.Rent(_capacity);
_positionBuffer = null;
}
internal void Reset()
{
_disposed = false;
}
public void CheckDivisor(ulong divisor, ulong divisorCycle, ReadOnlySpan<ulong> primes, Span<byte> hits)
{
if (_disposed)
{
throw new ObjectDisposedException(nameof(DivisorScanSession));
}
MersenneNumberDivisorByDivisorGpuTester owner = _owner;
int primesLength = primes.Length;
if (primesLength == 0)
{
return;
}
// The production pipeline never adjusts the GPU batch size after a session
// is initialized, so the buffers allocated in the constructor remain
// large enough for every launch.
MontgomeryDivisorData divisorData = MontgomeryDivisorDataCache.Get(divisor);
var exponentStepper = new ExponentRemainderStepper(divisorData);
if (!exponentStepper.IsValidModulus)
{
hits.Clear();
return;
}
bool useDivisorCycles = owner._useDivisorCycles;
if (!useDivisorCycles)
{
ProcessWithoutCycle(ref exponentStepper, divisorData, primes, hits);
return;
}
if (divisorCycle == 0UL)
{
throw new InvalidOperationException($"Missing divisor cycle for divisor {divisor}.");
}
var cycleStepper = new CycleRemainderStepper(divisorCycle);
ulong initialCycleRemainder = cycleStepper.Initialize(primes[0]);
ProcessWithCycle(ref exponentStepper, ref cycleStepper, initialCycleRemainder, divisorCycle, divisorData, primes, hits);
}
private void ProcessWithoutCycle(
ref ExponentRemainderStepper exponentStepper,
in MontgomeryDivisorData divisorData,
ReadOnlySpan<ulong> primes,
Span<byte> hits)
{
Action<Index1D, MontgomeryDivisorData, ArrayView<ulong>, ArrayView<ulong>> kernel = _kernel;
ArrayView1D<ulong, Stride1D.Dense> exponentsView = _exponentsBuffer.View;
ArrayView1D<ulong, Stride1D.Dense> resultsView = _resultsBuffer.View;
Span<ulong> hostSpan = _hostBuffer.AsSpan(0, _capacity);
int primesLength = primes.Length;
int gpuBatchSize = _owner._gpuBatchSize;
int offset = 0;
while (offset < primesLength)
{
int batchSize = Math.Min(gpuBatchSize, primesLength - offset);
ReadOnlySpan<ulong> primesSlice = primes.Slice(offset, batchSize);
Span<byte> hitsSlice = hits.Slice(offset, batchSize);
Span<ulong> exponentSlice = hostSpan[..batchSize];
bool hasState = exponentStepper.HasState;
ulong previousExponent = exponentStepper.PreviousExponent;
int startIndex = 0;
if (!hasState)
{
ulong primeValue = primesSlice[0];
exponentSlice[0] = primeValue;
previousExponent = primeValue;
hasState = true;
startIndex = 1;
}
for (int i = startIndex; i < batchSize; i++)
{
ulong primeValue = primesSlice[i];
exponentSlice[i] = primeValue - previousExponent;
previousExponent = primeValue;
}
ArrayView1D<ulong, Stride1D.Dense> exponentView = exponentsView.SubView(0, batchSize);
exponentView.CopyFromCPU(ref MemoryMarshal.GetReference(exponentSlice), batchSize);
ArrayView1D<ulong, Stride1D.Dense> resultView = resultsView.SubView(0, batchSize);
kernel(batchSize, divisorData, exponentView, resultView);
resultView.CopyToCPU(ref MemoryMarshal.GetReference(exponentSlice), batchSize);
bool requiresInitialization = !exponentStepper.HasState;
for (int i = 0; i < batchSize; i++)
{
ulong primeValue = primesSlice[i];
ulong montgomeryResult = exponentSlice[i];
bool isUnity;
if (requiresInitialization)
{
exponentStepper.TryInitializeFromMontgomeryResult(primeValue, montgomeryResult, out isUnity);
requiresInitialization = false;
}
else
{
exponentStepper.TryAdvanceWithMontgomeryDelta(primeValue, montgomeryResult, out isUnity);
}
hitsSlice[i] = isUnity ? (byte)1 : (byte)0;
}
offset += batchSize;
}
}
private void ProcessWithCycle(
ref ExponentRemainderStepper exponentStepper,
ref CycleRemainderStepper cycleStepper,
ulong initialCycleRemainder,
ulong divisorCycle,
in MontgomeryDivisorData divisorData,
ReadOnlySpan<ulong> primes,
Span<byte> hits)
{
Action<Index1D, MontgomeryDivisorData, ArrayView<ulong>, ArrayView<ulong>> kernel = _kernel;
ArrayView1D<ulong, Stride1D.Dense> exponentsView = _exponentsBuffer.View;
ArrayView1D<ulong, Stride1D.Dense> resultsView = _resultsBuffer.View;
int capacity = _capacity;
Span<ulong> hostSpan = _hostBuffer.AsSpan(0, capacity);
int[]? positionBuffer = _positionBuffer;
if (positionBuffer is null)
{
// Session construction already enforces the batch capacity, so we only
// need to rent the position buffer on the first cycle-enabled invocation.
positionBuffer = ArrayPool<int>.Shared.Rent(capacity);
_positionBuffer = positionBuffer;
}
Span<int> positionSpan = positionBuffer.AsSpan(0, capacity);
int gpuBatchSize = _owner._gpuBatchSize;
int primesLength = primes.Length;
int offset = 0;
bool cycleRemainderPending = true;
while (offset < primesLength)
{
int batchSize = Math.Min(gpuBatchSize, primesLength - offset);
ReadOnlySpan<ulong> primesSlice = primes.Slice(offset, batchSize);
Span<byte> hitsSlice = hits.Slice(offset, batchSize);
int computeCount = 0;
bool hasState = exponentStepper.HasState;
ulong previousExponent = exponentStepper.PreviousExponent;
bool useInitialRemainder = cycleRemainderPending;
for (int i = 0; i < batchSize; i++)
{
hitsSlice[i] = 0;
ulong primeValue = primesSlice[i];
ulong remainder = useInitialRemainder
? initialCycleRemainder
: cycleStepper.ComputeNext(primeValue);
useInitialRemainder = false;
if (remainder != 0UL)
{
continue;
}
ulong workValue;
if (!hasState)
{
workValue = primeValue;
hasState = true;
}
else
{
workValue = primeValue - previousExponent;
}
previousExponent = primeValue;
if (workValue >= divisorCycle)
{
workValue %= divisorCycle;
}
hostSpan[computeCount] = workValue;
positionSpan[computeCount] = i;
computeCount++;
}
cycleRemainderPending = useInitialRemainder;
if (computeCount > 0)
{
Span<ulong> exponentSlice = hostSpan[..computeCount];
ArrayView1D<ulong, Stride1D.Dense> exponentView = exponentsView.SubView(0, computeCount);
exponentView.CopyFromCPU(ref MemoryMarshal.GetReference(exponentSlice), computeCount);
ArrayView1D<ulong, Stride1D.Dense> resultView = resultsView.SubView(0, computeCount);
kernel(computeCount, divisorData, exponentView, resultView);
resultView.CopyToCPU(ref MemoryMarshal.GetReference(exponentSlice), computeCount);
bool requiresInitialization = !exponentStepper.HasState;
for (int i = 0; i < computeCount; i++)
{
int position = positionSpan[i];
ulong primeValue = primesSlice[position];
ulong montgomeryResult = exponentSlice[i];
bool isUnity;
if (requiresInitialization)
{
exponentStepper.TryInitializeFromMontgomeryResult(primeValue, montgomeryResult, out isUnity);
requiresInitialization = false;
}
else
{
exponentStepper.TryAdvanceWithMontgomeryDelta(primeValue, montgomeryResult, out isUnity);
}
hitsSlice[position] = isUnity ? (byte)1 : (byte)0;
}
}
offset += batchSize;
}
}
public void Dispose()
{
if (_disposed)
{
return;
}
_disposed = true;
_owner._sessionPool.Add(this);
}
}
private static void ComputeMontgomeryExponentKernel(Index1D index, MontgomeryDivisorData divisor, ArrayView<ulong> exponents, ArrayView<ulong> results)
{
ulong modulus = divisor.Modulus;
if (modulus <= 1UL || (modulus & 1UL) == 0UL)
{
results[index] = 0UL;
return;
}
ulong exponent = exponents[index];
results[index] = exponent.Pow2MontgomeryModMontgomery(divisor);
}
public ulong DivisorLimit
{
get
{
lock (_sync)
{
if (!_isConfigured)
{
throw new InvalidOperationException("ConfigureFromMaxPrime must be called before using the tester.");
}
return _divisorLimit;
}
}
}
private BatchResources RentBatchResources(Accelerator accelerator, int capacity)
{
var bag = _resourcePools.GetOrAdd(accelerator, static _ => []);
if (bag.TryTake(out BatchResources? resources))
{
return resources;
}
return new BatchResources(accelerator, capacity);
}
private void ReturnBatchResources(Accelerator accelerator, BatchResources resources) => _resourcePools.GetOrAdd(accelerator, static _ => []).Add(resources);
private sealed class BatchResources : IDisposable
{
internal BatchResources(Accelerator accelerator, int capacity)
{
DivisorsBuffer = accelerator.Allocate1D<MontgomeryDivisorData>(capacity);
ExponentBuffer = accelerator.Allocate1D<ulong>(capacity);
HitsBuffer = accelerator.Allocate1D<byte>(capacity);
Divisors = ArrayPool<ulong>.Shared.Rent(capacity);
Exponents = ArrayPool<ulong>.Shared.Rent(capacity);
Hits = ArrayPool<byte>.Shared.Rent(capacity);
DivisorData = ArrayPool<MontgomeryDivisorData>.Shared.Rent(capacity);
Capacity = capacity;
}
internal readonly MemoryBuffer1D<MontgomeryDivisorData, Stride1D.Dense> DivisorsBuffer;
internal readonly MemoryBuffer1D<ulong, Stride1D.Dense> ExponentBuffer;
internal readonly MemoryBuffer1D<byte, Stride1D.Dense> HitsBuffer;
internal readonly ulong[] Divisors;
internal readonly ulong[] Exponents;
internal readonly byte[] Hits;
internal readonly MontgomeryDivisorData[] DivisorData;
internal readonly int Capacity;
public void Dispose()
{
DivisorsBuffer.Dispose();
ExponentBuffer.Dispose();
HitsBuffer.Dispose();
ArrayPool<ulong>.Shared.Return(Divisors, clearArray: false);
ArrayPool<ulong>.Shared.Return(Exponents, clearArray: false);
ArrayPool<byte>.Shared.Return(Hits, clearArray: false);
ArrayPool<MontgomeryDivisorData>.Shared.Return(DivisorData, clearArray: false);
}
}
private sealed class AcceleratorReferenceComparer : IEqualityComparer<Accelerator>
{
public static AcceleratorReferenceComparer Instance { get; } = new();
public bool Equals(Accelerator? x, Accelerator? y) => ReferenceEquals(x, y);
public int GetHashCode(Accelerator obj) => RuntimeHelpers.GetHashCode(obj);
}
public ulong GetAllowedMaxDivisor(ulong prime)
{
lock (_sync)
{
if (!_isConfigured)
{
throw new InvalidOperationException("ConfigureFromMaxPrime must be called before using the tester.");
}
return ComputeAllowedMaxDivisor(prime, _divisorLimit);
}
}
public DivisorScanSession CreateDivisorSession()
{
lock (_sync)
{
if (!_isConfigured)
{
throw new InvalidOperationException("ConfigureFromMaxPrime must be called before using the tester.");
}
if (_sessionPool.TryTake(out DivisorScanSession? session))
{
session.Reset();
return session;
}
return new DivisorScanSession(this);
}
}
IMersenneNumberDivisorByDivisorTester.IDivisorScanSession IMersenneNumberDivisorByDivisorTester.CreateDivisorSession() => CreateDivisorSession();
}