Add support for .NET Framework 4.7.1 and .NET Standard 2.1

.github/workflows/integration.yml

@@ -13,15 +13,22 @@ jobs:
 
     steps:
     - uses: actions/checkout@v4
+
     - name: Setup .NET
       uses: actions/setup-dotnet@v3
       with:
         dotnet-version: 8.0.x
+
+    - name: Install Mono
+      run: sudo apt-get install mono-complete -y
+      shell: bash
+
     - name: Run integration tests
       run: dotnet test --verbosity normal -p:CollectCoverage=true -p:CoverletOutputFormat=opencover DotMP-Tests
+
     - name: Upload coverage reports to Codecov
       uses: codecov/codecov-action@v3
       with:
-        files: coverage.net6.0.opencover.xml
+        files: coverage.net8.0.opencover.xml
         directory: DotMP-Tests
         token: ${{ secrets.CODECOV_TOKEN }}

DotMP-Tests/CPUTests.cs

@@ -292,10 +292,10 @@ public void Reduction_collapse_works()
             DotMP.Parallel.ParallelForReductionCollapse((256, 512), (512, 600),
                                                         op: Operations.Add, reduce_to: ref total_iters_executed,
                                                         num_threads: 8, chunk_size: 7, schedule: Schedule.Static,
-                                                        action: (ref int total_iters_executed, int i, int j) =>
+                                                        action: (ref int total_iters_executed_loc, int i, int j) =>
             {
                 DotMP.Atomic.Inc(ref iters_hit[i, j]);
-                total_iters_executed += 1;
+                total_iters_executed_loc += 1;
             });
 
             for (int i = 0; i < 1024; i++)
@@ -315,10 +315,10 @@ public void Reduction_collapse_works()
             DotMP.Parallel.ParallelForReductionCollapse((35, 64), (16, 100), (10, 62),
                                                         op: Operations.Add, reduce_to: ref total_iters_executed,
                                                         num_threads: 8, chunk_size: 3, schedule: Schedule.Dynamic,
-                                                        action: (ref int total_iters_executed, int i, int j, int k) =>
+                                                        action: (ref int total_iters_executed_loc, int i, int j, int k) =>
             {
                 DotMP.Atomic.Inc(ref iters_hit_3[i, j, k]);
-                total_iters_executed += 1;
+                total_iters_executed_loc += 1;
             });
 
             for (int i = 0; i < 128; i++)
@@ -339,10 +339,10 @@ public void Reduction_collapse_works()
             DotMP.Parallel.ParallelForReductionCollapse((1, 31), (10, 16), (5, 20), (21, 30),
                                                         op: Operations.Add, reduce_to: ref total_iters_executed,
                                                         num_threads: 8, chunk_size: 11, schedule: Schedule.Static,
-                                                        action: (ref int total_iters_executed, int i, int j, int k, int l) =>
+                                                        action: (ref int total_iters_executed_loc, int i, int j, int k, int l) =>
             {
                 DotMP.Atomic.Inc(ref iters_hit_4[i, j, k, l]);
-                total_iters_executed += 1;
+                total_iters_executed_loc += 1;
             });
 
             total_iters_executed.Should().Be((31 - 1) * (16 - 10) * (20 - 5) * (30 - 21));
@@ -351,10 +351,10 @@ public void Reduction_collapse_works()
             DotMP.Parallel.ParallelForReductionCollapse(new (int, int)[] { (1, 31), (10, 16), (5, 20), (21, 30) },
                                                         op: Operations.Add, reduce_to: ref total_iters_executed,
                                                         num_threads: 8, chunk_size: 11, schedule: Schedule.Static,
-                                                        action: (ref int total_iters_executed, int[] indices) =>
+                                                        action: (ref int total_iters_executed_loc, int[] indices) =>
             {
                 DotMP.Atomic.Inc(ref iters_hit_4[indices[0], indices[1], indices[2], indices[3]]);
-                total_iters_executed += 1;
+                total_iters_executed_loc += 1;
             });
 
             total_iters_executed.Should().Be((31 - 1) * (16 - 10) * (20 - 5) * (30 - 21));
@@ -663,6 +663,7 @@ public void Atomic_works()
             long_totals[2].Should().Be((long)threads * 2);
             ulong_totals[2].Should().Be((ulong)threads * 2);
 
+#if NET6_0_OR_GREATER
             //and
             DotMP.Parallel.ParallelRegion(num_threads: threads, action: () =>
             {
@@ -712,6 +713,7 @@ public void Atomic_works()
             uint_totals[4].Should().Be((uint)res);
             long_totals[4].Should().Be((long)res);
             ulong_totals[4].Should().Be((ulong)res);
+#endif
 
             uint_totals[5] = threads * 2 + 1;
             ulong_totals[5] = threads * 2 + 3;
@@ -766,14 +768,14 @@ public void Ordered_works()
         [Fact]
         public void Reduction_works()
         {
-            int total = 0;
+            int total_int = 0;
 
-            DotMP.Parallel.ParallelForReduction(0, 1024, DotMP.Operations.Add, ref total, num_threads: 8, chunk_size: 1, schedule: DotMP.Schedule.Static, action: (ref int total, int i) =>
+            DotMP.Parallel.ParallelForReduction(0, 1024, DotMP.Operations.Add, ref total_int, num_threads: 8, chunk_size: 1, schedule: DotMP.Schedule.Static, action: (ref int total, int i) =>
             {
                 total += i;
             });
 
-            total.Should().Be(1024 * 1023 / 2);
+            total_int.Should().Be(1024 * 1023 / 2);
 
             long total_long = 0;
 
@@ -1691,7 +1693,7 @@ private static uint CreateRegion()
 
             DotMP.Parallel.ParallelRegion(() =>
             {
-                Interlocked.Add(ref threads_spawned, 1);
+                DotMP.Atomic.Inc(ref threads_spawned);
             });
 
             return threads_spawned;

DotMP-Tests/DotMP-Tests.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFrameworks>net6.0;net7.0;net8.0</TargetFrameworks>
+    <TargetFrameworks>net471;net8.0</TargetFrameworks>
   </PropertyGroup>
 
   <ItemGroup>

DotMP-Tests/GPUTests.cs

@@ -2,7 +2,6 @@
 using System.Collections.Generic;
 using System.Diagnostics;
 using System.Linq;
-using System.Text.Json.Serialization;
 using System.Threading;
 using DotMP;
 using DotMP.GPU;
@@ -13,6 +12,7 @@
 
 namespace DotMPTests
 {
+#if NET6_0_OR_GREATER
     /// <summary>
     /// GPU tests for the DotMP library.
     /// </summary>
@@ -133,4 +133,5 @@ private void random_init<T>(T[] arr)
             }
         }
     }
+#endif
 }

DotMP/Atomic.cs

@@ -70,6 +70,7 @@ public static int Dec(ref int target)
             return Interlocked.Decrement(ref target);
         }
 
+#if NET6_0_OR_GREATER
         /// <summary>
         /// Performs a bitwise And operation on two specified 32-bit integers and replaces the first integer with the result, as an atomic operation.
         /// </summary>
@@ -91,6 +92,7 @@ public static int Or(ref int target, int value)
         {
             return Interlocked.Or(ref target, value);
         }
+#endif
         #endregion
 
         #region UInt32
@@ -102,7 +104,11 @@ public static int Or(ref int target, int value)
         /// <returns>The new value stored as a result of the operation.</returns>
         public static uint Add(ref uint target, uint value)
         {
+#if NET6_0_OR_GREATER
             return Interlocked.Add(ref target, value);
+#else
+            return unchecked((uint)Interlocked.Add(ref Unsafe.As<uint, int>(ref target), Unsafe.As<uint, int>(ref value)));
+#endif
         }
 
         /// <summary>
@@ -114,7 +120,11 @@ public static uint Add(ref uint target, uint value)
         public static uint Sub(ref uint target, uint value)
         {
             uint neg = ~value + 1;
+#if NET6_0_OR_GREATER
             return Interlocked.Add(ref target, neg);
+#else
+            return unchecked((uint)Interlocked.Add(ref Unsafe.As<uint, int>(ref target), Unsafe.As<uint, int>(ref neg)));
+#endif
         }
 
         /// <summary>
@@ -124,7 +134,11 @@ public static uint Sub(ref uint target, uint value)
         /// <returns>The new value stored as a result of the operation.</returns>
         public static uint Inc(ref uint target)
         {
+#if NET6_0_OR_GREATER
             return Interlocked.Increment(ref target);
+#else
+            return unchecked((uint)Interlocked.Increment(ref Unsafe.As<uint, int>(ref target)));
+#endif
         }
 
         /// <summary>
@@ -134,9 +148,14 @@ public static uint Inc(ref uint target)
         /// <returns>The new value stored as a result of the operation.</returns>
         public static uint Dec(ref uint target)
         {
+#if NET6_0_OR_GREATER
             return Interlocked.Decrement(ref target);
+#else
+            return unchecked((uint)Interlocked.Decrement(ref Unsafe.As<uint, int>(ref target)));
+#endif
         }
 
+#if NET6_0_OR_GREATER
         /// <summary>
         /// Performs a bitwise And operation on two specified 32-bit unsigned integers and replaces the first integer with the result, as an atomic operation.
         /// </summary>
@@ -158,6 +177,7 @@ public static uint Or(ref uint target, uint value)
         {
             return Interlocked.Or(ref target, value);
         }
+#endif
         #endregion
 
         #region Int64
@@ -203,6 +223,7 @@ public static long Dec(ref long target)
             return Interlocked.Decrement(ref target);
         }
 
+#if NET6_0_OR_GREATER
         /// <summary>
         /// Performs a bitwise And operation on two specified 64-bit integers and replaces the first integer with the result, as an atomic operation.
         /// </summary>
@@ -224,6 +245,7 @@ public static long Or(ref long target, long value)
         {
             return Interlocked.Or(ref target, value);
         }
+#endif
         #endregion
 
         #region UInt64
@@ -235,7 +257,11 @@ public static long Or(ref long target, long value)
         /// <returns>The new value stored as a result of the operation.</returns>
         public static ulong Add(ref ulong target, ulong value)
         {
+#if NET6_0_OR_GREATER
             return Interlocked.Add(ref target, value);
+#else
+            return unchecked((ulong)Interlocked.Add(ref Unsafe.As<ulong, long>(ref target), Unsafe.As<ulong, long>(ref value)));
+#endif
         }
 
         /// <summary>
@@ -247,7 +273,11 @@ public static ulong Add(ref ulong target, ulong value)
         public static ulong Sub(ref ulong target, ulong value)
         {
             ulong neg = ~value + 1;
+#if NET6_0_OR_GREATER
             return Interlocked.Add(ref target, neg);
+#else
+            return unchecked((ulong)Interlocked.Add(ref Unsafe.As<ulong, long>(ref target), Unsafe.As<ulong, long>(ref neg)));
+#endif
         }
 
         /// <summary>
@@ -257,7 +287,11 @@ public static ulong Sub(ref ulong target, ulong value)
         /// <returns>The new value stored as a result of the operation.</returns>
         public static ulong Inc(ref ulong target)
         {
+#if NET6_0_OR_GREATER
             return Interlocked.Increment(ref target);
+#else
+            return unchecked((ulong)Interlocked.Increment(ref Unsafe.As<ulong, long>(ref target)));
+#endif
         }
 
         /// <summary>
@@ -267,9 +301,14 @@ public static ulong Inc(ref ulong target)
         /// <returns>The new value stored as a result of the operation.</returns>
         public static ulong Dec(ref ulong target)
         {
+#if NET6_0_OR_GREATER
             return Interlocked.Decrement(ref target);
+#else
+            return unchecked((ulong)Interlocked.Decrement(ref Unsafe.As<ulong, long>(ref target)));
+#endif
         }
 
+#if NET6_0_OR_GREATER
         /// <summary>
         /// Performs a bitwise And operation on two specified 64-bit unsigned integers and replaces the first integer with the result, as an atomic operation.
         /// </summary>
@@ -291,6 +330,7 @@ public static ulong Or(ref ulong target, ulong value)
         {
             return Interlocked.Or(ref target, value);
         }
+#endif
         #endregion
     }
 }

DotMP/DependencyGraph.cs

@@ -19,8 +19,6 @@
 using System.Collections.Generic;
 using System.Threading;
 
-#nullable enable
-
 namespace DotMP
 {
     /// <summary>
@@ -48,7 +46,6 @@ internal IntWrapper(int @int)
     /// </summary>
     internal class DAG<T, U> : IDisposable
         where T : struct
-        where U : class?
     {
         /// <summary>
         /// Counter for remaining tasks in queue.
@@ -113,9 +110,9 @@ internal void AddItem(T id, U item, T[] dependencies)
                 else
                     satisfies_dependency[d].Add(id);
 
-            unmet_dependencies.TryAdd(id, new IntWrapper(dependency_count));
+            unmet_dependencies.Add(id, new IntWrapper(dependency_count));
 
-            satisfies_dependency.TryAdd(id, new List<T>());
+            satisfies_dependency.Add(id, new List<T>());
 
             if (dependency_count == 0)
                 no_dependencies.Add(id);
@@ -130,7 +127,7 @@ internal void AddItem(T id, U item, T[] dependencies)
         /// <param name="id">The ID of the item returned from the DAG.</param>
         /// <param name="tasks_remaining">The number of tasks remaining in the queue.</param>
         /// <returns>Whether or not there was an item to be returned.</returns>
-        internal bool GetNextItem(out U? item, out T id, out int tasks_remaining)
+        internal bool GetNextItem(out U item, out T id, out int tasks_remaining)
         {
             tasks_remaining = this.tasks_remaining;
 
@@ -140,7 +137,7 @@ internal bool GetNextItem(out U? item, out T id, out int tasks_remaining)
             }
             else
             {
-                item = null;
+                item = default;
                 return false;
             }
         }

DotMP/DotMP.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFrameworks>net6.0;net7.0;net8.0</TargetFrameworks>
+    <TargetFrameworks>netstandard2.1;net471;net6.0;net7.0;net8.0</TargetFrameworks>
     <RootNamespace>DotMP</RootNamespace>
     <PackageId>DotMP</PackageId>
     <Version>2.0-pre1</Version>
@@ -24,6 +24,8 @@
   </ItemGroup>
 
   <ItemGroup>
+    <PackageReference Include="Microsoft.CSharp" Version="4.7.0" />
+    <PackageReference Include="System.Runtime.CompilerServices.Unsafe" Version="6.0.0" />
     <PackageReference Include="ILGPU" Version="1.5.1" />
     <PackageReference Include="T4.Build" Version="0.2.4" />
 

DotMP/ForkedRegion.cs

@@ -64,10 +64,15 @@ internal Thread CreateThread(Action omp_fn, int tid, uint num_threads)
                 }
                 catch (Exception ex)
                 {
+#if NET6_0_OR_GREATER
                     this.ex ??= ex;
+#else
+                    if (this.ex == null)
+                        this.ex = ex;
+#endif
                     Parallel.canceled = true;
 
-                    if (ex is not ThreadInterruptedException)
+                    if (!(ex is ThreadInterruptedException))
                         for (int i = 0; i < num_threads; i++)
                             if (i != tid)
                                 threads[i].Interrupt();
@@ -182,7 +187,7 @@ internal void StartThreadpool()
 
             in_parallel = false;
 
-            if (reg.ex is not null)
+            if (reg.ex != null)
                 System.Runtime.ExceptionServices.ExceptionDispatchInfo.Capture(reg.ex).Throw();
         }
     }