Remove IDisposable usage and using declarations

PerfectNumbers.Core/Gpu/GpuKernelPool.cs

@@ -76,10 +76,10 @@ public readonly struct ResiduePrimeViews(
     public readonly ArrayView1D<ulong, Stride1D.Dense> LastSevenPow2 = lastSevenPow2;
 }
 
-public ref struct GpuKernelLease(IDisposable limiter, GpuContextLease gpu, KernelContainer kernels)
+public ref struct GpuKernelLease(GpuPrimeWorkLimiter.Lease limiter, GpuContextLease gpu, KernelContainer kernels)
 {
     private bool disposedValue;
-    private IDisposable? _limiter = limiter;
+    private GpuPrimeWorkLimiter.Lease? _limiter = limiter;
     private GpuContextLease? _gpu = gpu;
     private KernelContainer _kernels = kernels;
     private AcceleratorStream? _stream;

PerfectNumbers.Core/Gpu/GpuPrimeWorkLimiter.cs

@@ -6,13 +6,13 @@ public static class GpuPrimeWorkLimiter
     private static readonly object _lock = new();
     private static int _currentLimit = 1;
 
-    public static IDisposable Acquire()
+    public static Lease Acquire()
     {
         // TODO: Inline the pooled limiter guard from the GpuLimiterThroughputBenchmarks so prime-sieve
         // GPU jobs stop allocating Releaser instances on every acquisition.
         var sem = _semaphore;
         sem.Wait();
-        return new Releaser(sem);
+        return new Lease(sem);
     }
 
     public static void SetLimit(int value)
@@ -36,12 +36,12 @@ public static class GpuPrimeWorkLimiter
         }
     }
 
-    private sealed class Releaser : IDisposable
+    public sealed class Lease
     {
         private readonly SemaphoreSlim _sem;
         private bool _disposed;
 
-        public Releaser(SemaphoreSlim sem)
+        public Lease(SemaphoreSlim sem)
         {
             _sem = sem;
         }

PerfectNumbers.Core/Gpu/GpuWorkLimiter.cs

@@ -6,14 +6,14 @@ public static class GpuWorkLimiter
     private static readonly object _lock = new();
     private static int _currentLimit = 1;
 
-    public static IDisposable Acquire()
+    public static Lease Acquire()
     {
         // TODO: Replace the per-call Releaser allocation with the pooled struct-based guard from the
         // GpuLimiterThroughputBenchmarks so limiter acquisition does not allocate when we enter the
         // GPU scanning hot path.
         var sem = _semaphore;
         sem.Wait();
-        return new Releaser(sem);
+        return new Lease(sem);
     }
 
     public static void SetLimit(int value)
@@ -40,12 +40,12 @@ public static class GpuWorkLimiter
         }
     }
 
-    private sealed class Releaser : IDisposable
+    public sealed class Lease
     {
         private readonly SemaphoreSlim _sem;
         private bool _disposed;
 
-        public Releaser(SemaphoreSlim sem)
+        public Lease(SemaphoreSlim sem)
         {
             _sem = sem;
         }

PerfectNumbers.Core/Gpu/MersenneNumberDivisorByDivisorGpuTester.cs

@@ -844,7 +844,7 @@ public sealed class MersenneNumberDivisorByDivisorGpuTester : IMersenneNumberDiv
 
     private void ReturnBatchResources(Accelerator accelerator, BatchResources resources) => _resourcePools.GetOrAdd(accelerator, static _ => []).Add(resources);
 
-    private sealed class BatchResources : IDisposable
+    private sealed class BatchResources
     {
         internal BatchResources(MersenneNumberDivisorByDivisorGpuTester owner, Accelerator accelerator, int capacity)
         {
@@ -948,7 +948,7 @@ public sealed class MersenneNumberDivisorByDivisorGpuTester : IMersenneNumberDiv
         return ComputeAllowedMaxDivisor(prime, _divisorLimit);
     }
 
-    public DivisorScanSession CreateDivisorSession()
+    public IMersenneNumberDivisorByDivisorTester.IDivisorScanSession CreateDivisorSession()
     {
         // Divisor sessions are handed out only after configuration, so this guard would never trigger on the
         // production path.
@@ -965,8 +965,6 @@ public sealed class MersenneNumberDivisorByDivisorGpuTester : IMersenneNumberDiv
 
         return new DivisorScanSession(this);
     }
-
-    IMersenneNumberDivisorByDivisorTester.IDivisorScanSession IMersenneNumberDivisorByDivisorTester.CreateDivisorSession() => CreateDivisorSession();
 }
 
 

PerfectNumbers.Core/Gpu/MersenneNumberDivisorCandidateGpuEvaluator.cs

@@ -6,7 +6,7 @@ using ILGPU.Runtime;
 
 namespace PerfectNumbers.Core.Gpu;
 
-internal sealed class MersenneNumberDivisorCandidateGpuEvaluator : IDisposable
+internal sealed class MersenneNumberDivisorCandidateGpuEvaluator
 {
     private const int RemainderCount = 6;
 

PerfectNumbers.Core/Gpu/MersenneNumberDivisorMontgomeryGpuBuilder.cs

@@ -7,7 +7,7 @@ using ILGPU.Runtime;
 
 namespace PerfectNumbers.Core.Gpu;
 
-internal sealed class MersenneNumberDivisorMontgomeryGpuBuilder : IDisposable
+internal sealed class MersenneNumberDivisorMontgomeryGpuBuilder
 {
     private readonly GpuContextPool.GpuContextLease _lease;
     private readonly Accelerator _accelerator;

PerfectNumbers.Core/Gpu/MersenneNumberDivisorRemainderGpuStepper.cs

@@ -6,7 +6,7 @@ using ILGPU.Runtime;
 
 namespace PerfectNumbers.Core.Gpu;
 
-internal sealed class MersenneNumberDivisorRemainderGpuStepper : IDisposable
+internal sealed class MersenneNumberDivisorRemainderGpuStepper
 {
     private const int RemainderCount = 6;
 

PerfectNumbers.Core/Gpu/MersenneNumberDivisorResidueGpuEvaluator.cs

@@ -7,7 +7,7 @@ using ILGPU.Runtime;
 
 namespace PerfectNumbers.Core.Gpu;
 
-internal sealed class MersenneNumberDivisorResidueGpuEvaluator : IDisposable
+internal sealed class MersenneNumberDivisorResidueGpuEvaluator
 {
     private readonly GpuContextPool.GpuContextLease _lease;
     private readonly Accelerator _accelerator;

PerfectNumbers.Core/Gpu/MersenneNumberLucasLehmerGpuTester.cs

@@ -327,8 +327,9 @@ public class MersenneNumberLucasLehmerGpuTester
             // TODO: Replace StreamWriter with the pooled TextFileWriter pipeline so persisting NTT
             // parameters reuses the zero-allocation buffered writes highlighted in the scanner I/O
             // benchmarks instead of allocating a new encoder per append.
-            using var writer = new StreamWriter(ParameterFilePath, append: true);
+            var writer = new StreamWriter(ParameterFilePath, append: true);
             writer.WriteLine($"{length} {modulus.High} {modulus.Low} {primitiveRoot.High} {primitiveRoot.Low}");
+            writer.Dispose();
         }
     }
 
@@ -338,7 +339,7 @@ public class MersenneNumberLucasLehmerGpuTester
         ulong foundRoot = 0UL;
         bool success = false;
         var processorCount = Environment.ProcessorCount;
-        using var cts = new System.Threading.CancellationTokenSource();
+        var cts = new System.Threading.CancellationTokenSource();
         object sync = new();
 
         // TODO: Move this Parallel.For to the shared low-overhead work scheduler once the NTT parameter
@@ -381,11 +382,13 @@ public class MersenneNumberLucasLehmerGpuTester
         {
             modulus = new GpuUInt128(0UL, foundCandidate);
             primitiveRoot = new GpuUInt128(0UL, foundRoot);
+            cts.Dispose();
             return true;
         }
 
         modulus = new GpuUInt128(0UL, 18446744069414584321UL);
         primitiveRoot = new GpuUInt128(0UL, 7UL);
+        cts.Dispose();
         return false;
     }
 

PerfectNumbers.Core/Gpu/MontgomeryOddPowerGpu.cs

@@ -64,31 +64,25 @@ internal static class MontgomeryOddPowerGpu
         var accelerator = lease.Accelerator;
         var stream = lease.Stream;
 
-        using var divisorBuffer = accelerator.Allocate1D<MontgomeryDivisorData>(divisorCount);
-        using var countBuffer = accelerator.Allocate1D<int>(divisorCount);
-        using var resultBuffer = accelerator.Allocate1D<ulong>(divisorCount * stride);
+        var divisorBuffer = accelerator.Allocate1D<MontgomeryDivisorData>(divisorCount);
+        var countBuffer = accelerator.Allocate1D<int>(divisorCount);
+        var resultBuffer = accelerator.Allocate1D<ulong>(divisorCount * stride);
 
-        try
-        {
-            divisorBuffer.View.CopyFromCPU(ref MemoryMarshal.GetReference(divisors), divisorCount);
-            countBuffer.View.CopyFromCPU(ref MemoryMarshal.GetReference(oddPowerCounts), divisorCount);
-            resultBuffer.MemSetToZero();
+        divisorBuffer.View.CopyFromCPU(ref MemoryMarshal.GetReference(divisors), divisorCount);
+        countBuffer.View.CopyFromCPU(ref MemoryMarshal.GetReference(oddPowerCounts), divisorCount);
+        resultBuffer.MemSetToZero();
 
-            var kernel = lease.MontgomeryOddPowerKernel;
-            kernel(stream, divisorCount, divisorBuffer.View, countBuffer.View, resultBuffer.View, stride);
-            stream.Synchronize();
+        var kernel = lease.MontgomeryOddPowerKernel;
+        kernel(stream, divisorCount, divisorBuffer.View, countBuffer.View, resultBuffer.View, stride);
+        stream.Synchronize();
 
-            resultBuffer.View.CopyToCPU(ref MemoryMarshal.GetReference(results), divisorCount * stride);
-            return true;
-        }
-        catch
-        {
-            return false;
-        }
-        finally
-        {
-            execution.Dispose();
-            lease.Dispose();
-        }
+        resultBuffer.View.CopyToCPU(ref MemoryMarshal.GetReference(results), divisorCount * stride);
+
+        resultBuffer.Dispose();
+        countBuffer.Dispose();
+        divisorBuffer.Dispose();
+        execution.Dispose();
+        lease.Dispose();
+        return true;
     }
 }

PerfectNumbers.Core/Gpu/NttGpuMath.cs

@@ -47,7 +47,7 @@ public static class NttGpuMath
 
     private static readonly ConcurrentDictionary<Accelerator, Action<Index1D, ArrayView<GpuUInt128>, int>> BitReverseKernelCache = new(); // TODO: Precompute bit-reversal kernels during boot so we can remove the concurrent lookup overhead flagged in the benchmarks.
 
-    private sealed class SquareCacheEntry : IDisposable
+    private sealed class SquareCacheEntry
     {
         public MemoryBuffer1D<GpuUInt128, Stride1D.Dense> Buffer { get; }
         public GpuUInt128 Root { get; }

PerfectNumbers.Core/IMersenneNumberDivisorByDivisorTester.cs

@@ -18,8 +18,10 @@ public interface IMersenneNumberDivisorByDivisorTester
 
     void PrepareCandidates(ReadOnlySpan<ulong> primes, Span<ulong> allowedMaxValues);
 
-    public interface IDivisorScanSession : IDisposable
+    public interface IDivisorScanSession
     {
         void CheckDivisor(ulong divisor, in MontgomeryDivisorData divisorData, ulong divisorCycle, ReadOnlySpan<ulong> primes, Span<byte> hits);
+
+        void Dispose();
     }
 }

PerfectNumbers.Core/MersenneDivisorCycles.cs

@@ -196,7 +196,7 @@ public class MersenneDivisorCycles
     public static IEnumerable<(ulong divisor, ulong cycleLength)> EnumerateStream(Stream compressor)
     {
         // Binary pairs: (ulong divisor, ulong cycle)
-        using var reader = new BinaryReader(compressor, Encoding.UTF8, leaveOpen: true);
+        var reader = new BinaryReader(compressor, Encoding.UTF8, leaveOpen: true);
         while (true)
         {
             ulong d, c;
@@ -207,6 +207,7 @@ public class MersenneDivisorCycles
             }
             catch (EndOfStreamException)
             {
+                reader.Dispose();
                 yield break;
             }
 
@@ -829,7 +830,7 @@ public class MersenneDivisorCycles
         // Start fresh to avoid mixing formats
         outputStream.SetLength(0L);
         outputStream.Position = 0L;
-        using var writer = new BinaryWriter(outputStream, Encoding.UTF8, leaveOpen: false);
+        var writer = new BinaryWriter(outputStream, Encoding.UTF8, leaveOpen: false);
         for (var taskIndex = 0; taskIndex < threads; taskIndex++)
         {
             ulong threadStart = start + (ulong)taskIndex * blockSize;
@@ -911,6 +912,7 @@ public class MersenneDivisorCycles
         }
 
         Task.WaitAll(tasks);
+        writer.Dispose();
     }
 
     public static void GenerateGpu(string path, ulong maxDivisor, int batchSize = 1_000_000, long skipCount = 0L, long nextPosition = 0L)
@@ -947,7 +949,7 @@ public class MersenneDivisorCycles
             outputStream.Position = 0L;
         }
 
-        using var writer = new BinaryWriter(outputStream, Encoding.UTF8, leaveOpen: false);
+        var writer = new BinaryWriter(outputStream, Encoding.UTF8, leaveOpen: false);
         try
         {
             while (skipCount > 0L && start <= maxDivisor)
@@ -1022,6 +1024,7 @@ public class MersenneDivisorCycles
             pool.Return(outCycles, clearArray: false);
         }
 
+        writer.Dispose();
         stream.Dispose();
         lease.Dispose();
 

PerfectNumbers.Core/PrimeFactorPartialResult.cs

@@ -3,7 +3,7 @@ using System.Buffers;
 
 namespace PerfectNumbers.Core
 {
-    internal sealed class PrimeFactorPartialResult : IDisposable
+    internal sealed class PrimeFactorPartialResult
     {
         [ThreadStatic]
         private static PrimeFactorPartialResult? s_poolHead;

PerfectNumbers.Core/PrimeTester.cs

@@ -176,7 +176,7 @@ public sealed class PrimeTester(bool useInternal = false)
             DevicePrimes.View.CopyFromCPU(primes);
         }
 
-        internal sealed class ScratchBuffers : IDisposable
+        internal sealed class ScratchBuffers
         {
             public MemoryBuffer1D<ulong, Stride1D.Dense> Input { get; private set; }
             public MemoryBuffer1D<byte, Stride1D.Dense> Output { get; private set; }

PerfectNumbers.Core/TextFileWriter.cs

@@ -3,7 +3,7 @@ namespace PerfectNumbers.Core;
 /// <summary>
 /// Provides thread-safe file writing for both text and binary data.
 /// </summary>
-public sealed class TextFileWriter : IDisposable
+public sealed class TextFileWriter
 {
     private readonly FileStream _stream;
     private StreamWriter? _textWriter;