Drop .NET Core 3.1 TFM

CommunityToolkit.HighPerformance/Buffers/MemoryOwner{T}.cs

@@ -6,7 +6,7 @@
 using System.Buffers;
 using System.Diagnostics;
 using System.Runtime.CompilerServices;
-#if NETCOREAPP3_1_OR_GREATER
+#if NET6_0_OR_GREATER
 using System.Runtime.InteropServices;
 #endif
 using CommunityToolkit.HighPerformance.Buffers.Views;
@@ -171,13 +171,13 @@ public Span<T> Span
                 ThrowObjectDisposedException();
             }
 
-#if NETCOREAPP3_1_OR_GREATER
+#if NET6_0_OR_GREATER
             ref T r0 = ref array!.DangerousGetReferenceAt(this.start);
 
-            // On .NET Core runtimes, we can manually create a span from the starting reference to
+            // On .NET 6+ runtimes, we can manually create a span from the starting reference to
             // skip the argument validations, which include an explicit null check, covariance check
             // for the array and the actual validation for the starting offset and target length. We
-            // only do this on .NET Core as we can leverage the runtime-specific array layout to get
+            // only do this on .NET 6+ as we can leverage the runtime-specific array layout to get
             // a fast access to the initial element, which makes this trick worth it. Otherwise, on
             // runtimes where we would need to at least access a static field to retrieve the base
             // byte offset within an SZ array object, we can get better performance by just using the

CommunityToolkit.HighPerformance/Buffers/SpanOwner{T}.cs

@@ -6,7 +6,7 @@
 using System.Buffers;
 using System.Diagnostics;
 using System.Runtime.CompilerServices;
-#if NETCOREAPP3_1_OR_GREATER
+#if NET6_0_OR_GREATER
 using System.Runtime.InteropServices;
 #endif
 using CommunityToolkit.HighPerformance.Buffers.Views;
@@ -141,7 +141,7 @@ public Span<T> Span
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         get
         {
-#if NETCOREAPP3_1_OR_GREATER
+#if NET6_0_OR_GREATER
             ref T r0 = ref this.array!.DangerousGetReference();
 
             return MemoryMarshal.CreateSpan(ref r0, this.length);

CommunityToolkit.HighPerformance/CommunityToolkit.HighPerformance.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFrameworks>netstandard2.0;netstandard2.1;netcoreapp3.1;net6.0;net7.0</TargetFrameworks>
+    <TargetFrameworks>netstandard2.0;netstandard2.1;net6.0;net7.0</TargetFrameworks>
   </PropertyGroup>
 
   <PropertyGroup>
@@ -47,23 +47,11 @@
 
     <When Condition="'$(TargetFramework)' == 'net6.0' OR '$(TargetFramework)' == 'net7.0'">
 
-      <!-- NETSTANDARD2_1_OR_GREATER: includes both .NET Standard 2.1, .NET Core 3.1 and .NET 6.
-           Additionally, also enable trimming support on .NET 6. -->
+      <!-- NETSTANDARD2_1_OR_GREATER: includes both .NET Standard 2.1 and .NET 6 and above -->
       <PropertyGroup>
         <DefineConstants>NETSTANDARD2_1_OR_GREATER</DefineConstants>
       </PropertyGroup>
     </When>
-
-    <When Condition="'$(TargetFramework)' == 'netcoreapp3.1'">
-      <PropertyGroup>
-        <DefineConstants>NETSTANDARD2_1_OR_GREATER</DefineConstants>
-      </PropertyGroup>
-
-      <!-- .NET Core 3.1 has the Unsafe type, but the version it ships with lacks Unsafe.IsNullRef<T> -->
-      <ItemGroup>
-        <PackageReference Include="System.Runtime.CompilerServices.Unsafe" Version="6.0.0" />
-      </ItemGroup>
-    </When>
   </Choose>
 
 </Project>

CommunityToolkit.HighPerformance/Extensions/ArrayExtensions.1D.cs

@@ -4,7 +4,7 @@
 
 using System;
 using System.Runtime.CompilerServices;
-#if NETCOREAPP3_1_OR_GREATER
+#if NET6_0_OR_GREATER
 using System.Runtime.InteropServices;
 #endif
 using CommunityToolkit.HighPerformance.Enumerables;
@@ -33,11 +33,6 @@ public static ref T DangerousGetReference<T>(this T[] array)
     {
 #if NET6_0_OR_GREATER
         return ref MemoryMarshal.GetArrayDataReference(array);
-#elif NETCOREAPP3_1
-        RawArrayData? arrayData = Unsafe.As<RawArrayData>(array)!;
-        ref T r0 = ref Unsafe.As<byte, T>(ref arrayData.Data);
-
-        return ref r0;
 #else
         IntPtr offset = RuntimeHelpers.GetArrayDataByteOffset<T>();
 
@@ -60,12 +55,6 @@ public static ref T DangerousGetReferenceAt<T>(this T[] array, int i)
         ref T r0 = ref MemoryMarshal.GetArrayDataReference(array);
         ref T ri = ref Unsafe.Add(ref r0, (nint)(uint)i);
 
-        return ref ri;
-#elif NETCOREAPP3_1
-        RawArrayData? arrayData = Unsafe.As<RawArrayData>(array)!;
-        ref T r0 = ref Unsafe.As<byte, T>(ref arrayData.Data);
-        ref T ri = ref Unsafe.Add(ref r0, (nint)(uint)i);
-
         return ref ri;
 #else
         IntPtr offset = RuntimeHelpers.GetArrayDataByteOffset<T>();
@@ -76,26 +65,6 @@ public static ref T DangerousGetReferenceAt<T>(this T[] array, int i)
 #endif
     }
 
-#if NETCOREAPP3_1
-    // Description taken from CoreCLR: see https://source.dot.net/#System.Private.CoreLib/src/System/Runtime/CompilerServices/RuntimeHelpers.CoreCLR.cs,285.
-    // CLR arrays are laid out in memory as follows (multidimensional array bounds are optional):
-    // [ sync block || pMethodTable || num components || MD array bounds || array data .. ]
-    //                 ^                                 ^                  ^ returned reference
-    //                 |                                 \-- ref Unsafe.As<RawArrayData>(array).Data
-    //                 \-- array
-    // The base size of an array includes all the fields before the array data,
-    // including the sync block and method table. The reference to RawData.Data
-    // points at the number of components, skipping over these two pointer-sized fields.
-    [StructLayout(LayoutKind.Sequential)]
-    private sealed class RawArrayData
-    {
-#pragma warning disable CS0649 // Unassigned fields
-        public IntPtr Length;
-        public byte Data;
-#pragma warning restore CS0649
-    }
-#endif
-
     /// <summary>
     /// Counts the number of occurrences of a given value into a target <typeparamref name="T"/> array instance.
     /// </summary>

CommunityToolkit.HighPerformance/Extensions/ArrayExtensions.2D.cs

@@ -30,11 +30,6 @@ public static ref T DangerousGetReference<T>(this T[,] array)
     {
 #if NET6_0_OR_GREATER
         return ref Unsafe.As<byte, T>(ref MemoryMarshal.GetArrayDataReference(array));
-#elif NETCOREAPP3_1
-        RawArray2DData? arrayData = Unsafe.As<RawArray2DData>(array)!;
-        ref T r0 = ref Unsafe.As<byte, T>(ref arrayData.Data);
-
-        return ref r0;
 #else
         IntPtr offset = RuntimeHelpers.GetArray2DDataByteOffset<T>();
 
@@ -65,13 +60,6 @@ public static ref T DangerousGetReferenceAt<T>(this T[,] array, int i, int j)
         ref T r0 = ref Unsafe.As<byte, T>(ref MemoryMarshal.GetArrayDataReference(array));
         ref T ri = ref Unsafe.Add(ref r0, index);
 
-        return ref ri;
-#elif NETCOREAPP3_1
-        RawArray2DData? arrayData = Unsafe.As<RawArray2DData>(array)!;
-        nint offset = ((nint)(uint)i * (nint)(uint)arrayData.Width) + (nint)(uint)j;
-        ref T r0 = ref Unsafe.As<byte, T>(ref arrayData.Data);
-        ref T ri = ref Unsafe.Add(ref r0, offset);
-
         return ref ri;
 #else
         int width = array.GetLength(1);
@@ -84,29 +72,6 @@ public static ref T DangerousGetReferenceAt<T>(this T[,] array, int i, int j)
 #endif
     }
 
-#if NETCOREAPP3_1
-    // Description adapted from CoreCLR: see https://source.dot.net/#System.Private.CoreLib/src/System/Runtime/CompilerServices/RuntimeHelpers.CoreCLR.cs,285.
-    // CLR 2D arrays are laid out in memory as follows:
-    // [ sync block || pMethodTable || Length (padded to IntPtr) || HxW || HxW bounds || array data .. ]
-    //                 ^                                                                 ^
-    //                 |                                                                 \-- ref Unsafe.As<RawArray2DData>(array).Data
-    //                 \-- array
-    // The length is always padded to IntPtr just like with SZ arrays.
-    // The total data padding is therefore 20 bytes on x86 (4 + 4 + 4 + 4 + 4), or 24 bytes on x64.
-    [StructLayout(LayoutKind.Sequential)]
-    private sealed class RawArray2DData
-    {
-#pragma warning disable CS0649 // Unassigned fields
-        public IntPtr Length;
-        public int Height;
-        public int Width;
-        public int HeightLowerBound;
-        public int WidthLowerBound;
-        public byte Data;
-#pragma warning restore CS0649
-    }
-#endif
-
     /// <summary>
     /// Returns a <see cref="RefEnumerable{T}"/> over a row in a given 2D <typeparamref name="T"/> array instance.
     /// </summary>

CommunityToolkit.HighPerformance/Extensions/ArrayExtensions.3D.cs

@@ -29,11 +29,6 @@ public static ref T DangerousGetReference<T>(this T[,,] array)
     {
 #if NET6_0_OR_GREATER
         return ref Unsafe.As<byte, T>(ref MemoryMarshal.GetArrayDataReference(array));
-#elif NETCOREAPP3_1
-        RawArray3DData? arrayData = Unsafe.As<RawArray3DData>(array)!;
-        ref T r0 = ref Unsafe.As<byte, T>(ref arrayData.Data);
-
-        return ref r0;
 #else
         IntPtr offset = RuntimeHelpers.GetArray3DDataByteOffset<T>();
 
@@ -68,15 +63,6 @@ public static ref T DangerousGetReferenceAt<T>(this T[,,] array, int i, int j, i
         ref T r0 = ref Unsafe.As<byte, T>(ref MemoryMarshal.GetArrayDataReference(array));
         ref T ri = ref Unsafe.Add(ref r0, index);
 
-        return ref ri;
-#elif NETCOREAPP3_1
-        RawArray3DData? arrayData = Unsafe.As<RawArray3DData>(array)!;
-        nint offset =
-            ((nint)(uint)i * (nint)(uint)arrayData.Height * (nint)(uint)arrayData.Width) +
-            ((nint)(uint)j * (nint)(uint)arrayData.Width) + (nint)(uint)k;
-        ref T r0 = ref Unsafe.As<byte, T>(ref arrayData.Data);
-        ref T ri = ref Unsafe.Add(ref r0, offset);
-
         return ref ri;
 #else
         int height = array.GetLength(1);
@@ -92,25 +78,6 @@ public static ref T DangerousGetReferenceAt<T>(this T[,,] array, int i, int j, i
 #endif
     }
 
-#if NETCOREAPP3_1
-    // See description for this in the 2D partial file.
-    // Using the CHW naming scheme here (like with RGB images).
-    [StructLayout(LayoutKind.Sequential)]
-    private sealed class RawArray3DData
-    {
-#pragma warning disable CS0649 // Unassigned fields
-        public IntPtr Length;
-        public int Channel;
-        public int Height;
-        public int Width;
-        public int ChannelLowerBound;
-        public int HeightLowerBound;
-        public int WidthLowerBound;
-        public byte Data;
-#pragma warning restore CS0649
-    }
-#endif
-
 #if NETSTANDARD2_1_OR_GREATER
     /// <summary>
     /// Creates a new <see cref="Memory{T}"/> over an input 3D <typeparamref name="T"/> array.

CommunityToolkit.HighPerformance/Extensions/StringExtensions.cs

@@ -26,7 +26,7 @@ public static class StringExtensions
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
     public static ref char DangerousGetReference(this string text)
     {
-#if NETCOREAPP3_1_OR_GREATER
+#if NET6_0_OR_GREATER
         return ref Unsafe.AsRef(text.GetPinnableReference());
 #else
         return ref MemoryMarshal.GetReference(text.AsSpan());
@@ -43,7 +43,7 @@ public static ref char DangerousGetReference(this string text)
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
     public static ref char DangerousGetReferenceAt(this string text, int i)
     {
-#if NETCOREAPP3_1_OR_GREATER
+#if NET6_0_OR_GREATER
         ref char r0 = ref Unsafe.AsRef(text.GetPinnableReference());
 #else
         ref char r0 = ref MemoryMarshal.GetReference(text.AsSpan());

CommunityToolkit.HighPerformance/Helpers/BitHelper.cs

@@ -3,7 +3,7 @@
 // See the LICENSE file in the project root for more information.
 
 using System.Runtime.CompilerServices;
-#if NETCOREAPP3_1_OR_GREATER
+#if NET6_0_OR_GREATER
 using System.Runtime.Intrinsics.X86;
 #endif
 
@@ -224,7 +224,7 @@ public static unsafe uint SetFlag(uint value, int n, bool flag)
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
     public static uint ExtractRange(uint value, byte start, byte length)
     {
-#if NETCOREAPP3_1_OR_GREATER
+#if NET6_0_OR_GREATER
         if (Bmi1.IsSupported)
         {
             return Bmi1.BitFieldExtract(value, start, length);
@@ -270,7 +270,7 @@ public static uint SetRange(uint value, byte start, byte length, uint flags)
         uint loadMask = highBits << start;
         uint storeMask = (flags & highBits) << start;
 
-#if NETCOREAPP3_1_OR_GREATER
+#if NET6_0_OR_GREATER
         if (Bmi1.IsSupported)
         {
             return Bmi1.AndNot(loadMask, value) | storeMask;
@@ -386,7 +386,7 @@ public static unsafe ulong SetFlag(ulong value, int n, bool flag)
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
     public static ulong ExtractRange(ulong value, byte start, byte length)
     {
-#if NETCOREAPP3_1_OR_GREATER
+#if NET6_0_OR_GREATER
         if (Bmi1.X64.IsSupported)
         {
             return Bmi1.X64.BitFieldExtract(value, start, length);
@@ -432,7 +432,7 @@ public static ulong SetRange(ulong value, byte start, byte length, ulong flags)
         ulong loadMask = highBits << start;
         ulong storeMask = (flags & highBits) << start;
 
-#if NETCOREAPP3_1_OR_GREATER
+#if NET6_0_OR_GREATER
         if (Bmi1.X64.IsSupported)
         {
             return Bmi1.X64.AndNot(loadMask, value) | storeMask;

CommunityToolkit.HighPerformance/Helpers/Internals/BitOperations.cs

@@ -5,10 +5,6 @@
 #if !NET6_0_OR_GREATER
 
 using System.Runtime.CompilerServices;
-#if NETCOREAPP3_1
-using System.Runtime.Intrinsics.X86;
-using static System.Numerics.BitOperations;
-#endif
 
 namespace CommunityToolkit.HighPerformance.Helpers.Internals;
 
@@ -29,22 +25,6 @@ internal static class BitOperations
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
     public static unsafe uint RoundUpToPowerOf2(uint value)
     {
-#if NETCOREAPP3_1
-        if (Lzcnt.IsSupported)
-        {
-            if (sizeof(nint) == 8)
-            {
-                return (uint)(0x1_0000_0000ul >> LeadingZeroCount(value - 1));
-            }
-            else
-            {
-                int shift = 32 - LeadingZeroCount(value - 1);
-
-                return (1u ^ (uint)(shift >> 5)) << shift;
-            }
-        }
-#endif
-
         // Based on https://graphics.stanford.edu/~seander/bithacks.html#RoundUpPowerOf2
         --value;
         value |= value >> 1;

CommunityToolkit.HighPerformance/Helpers/Internals/RuntimeHelpers.cs

@@ -75,7 +75,7 @@ public static nint GetArrayNativeLength(Array array)
         return (nint)array.LongLength;
     }
 
-#if !NETCOREAPP3_1_OR_GREATER
+#if !NET6_0_OR_GREATER
     /// <summary>
     /// Gets the byte offset to the first <typeparamref name="T"/> element in a SZ array.
     /// </summary>

azure-pipelines.yml

@@ -53,14 +53,14 @@ jobs:
 
   # Test solution #
 
+  # Run .NET 7 unit tests
+  - script: dotnet test --no-build -c $(Build.Configuration) -f net7.0 -l "trx;LogFileName=VSTestResults_net7.0.trx"
+    displayName: Run .NET 7 unit tests
+
   # Run .NET 6 unit tests
   - script: dotnet test --no-build -c $(Build.Configuration) -f net6.0 -l "trx;LogFileName=VSTestResults_net6.0.trx"
     displayName: Run .NET 6 unit tests
 
-  # Run .NET Core 3.1 unit tests
-  - script: dotnet test --no-build -c $(Build.Configuration) -f netcoreapp3.1 -l "trx;LogFileName=VSTestResults_netcoreapp3.1.trx"
-    displayName: Run .NET Core 3.1 unit tests
-
   # Run .NET Framework 4.7.2 unit tests
   - script: dotnet test --no-build -c $(Build.Configuration) -f net472 -l "trx;LogFileName=VSTestResults_net472.trx"
     displayName: Run .NET Framework 4.7.2 unit tests

tests/CommunityToolkit.Common.UnitTests/CommunityToolkit.Common.UnitTests.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFrameworks>net472;netcoreapp3.1;net6.0</TargetFrameworks>
+    <TargetFrameworks>net472;net6.0;net7.0</TargetFrameworks>
   </PropertyGroup>
 
   <ItemGroup>

tests/CommunityToolkit.Diagnostics.UnitTests/CommunityToolkit.Diagnostics.UnitTests.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFrameworks>net472;netcoreapp3.1;net6.0</TargetFrameworks>
+    <TargetFrameworks>net472;net6.0;net7.0</TargetFrameworks>
   </PropertyGroup>
 
   <ItemGroup>