Use where T : allows ref struct in runtime

Author: stephentoub

src/coreclr/System.Private.CoreLib/src/System/Runtime/CompilerServices/RuntimeHelpers.CoreCLR.cs

@@ -224,6 +224,7 @@ public static object GetUninitializedObject(
         /// <returns>true if given type is reference type or value type that contains references</returns>
         [Intrinsic]
         public static bool IsReferenceOrContainsReferences<T>()
+            // where T : allows ref struct // TODO https://github.com/dotnet/runtime/issues/102847
         {
             // The body of this function will be replaced by the EE with unsafe code!!!
             // See getILIntrinsicImplementationForRuntimeHelpers for how this happens.

src/libraries/System.Collections.Concurrent/ref/System.Collections.Concurrent.cs

@@ -101,13 +101,13 @@ public ConcurrentDictionary(int concurrencyLevel, int capacity, System.Collectio
         public System.Collections.Generic.ICollection<TValue> Values { get { throw null; } }
         public TValue AddOrUpdate(TKey key, System.Func<TKey, TValue> addValueFactory, System.Func<TKey, TValue, TValue> updateValueFactory) { throw null; }
         public TValue AddOrUpdate(TKey key, TValue addValue, System.Func<TKey, TValue, TValue> updateValueFactory) { throw null; }
-        public TValue AddOrUpdate<TArg>(TKey key, System.Func<TKey, TArg, TValue> addValueFactory, System.Func<TKey, TValue, TArg, TValue> updateValueFactory, TArg factoryArgument) { throw null; }
+        public TValue AddOrUpdate<TArg>(TKey key, System.Func<TKey, TArg, TValue> addValueFactory, System.Func<TKey, TValue, TArg, TValue> updateValueFactory, TArg factoryArgument) where TArg : allows ref struct { throw null; }
         public void Clear() { }
         public bool ContainsKey(TKey key) { throw null; }
         public System.Collections.Generic.IEnumerator<System.Collections.Generic.KeyValuePair<TKey, TValue>> GetEnumerator() { throw null; }
         public TValue GetOrAdd(TKey key, System.Func<TKey, TValue> valueFactory) { throw null; }
         public TValue GetOrAdd(TKey key, TValue value) { throw null; }
-        public TValue GetOrAdd<TArg>(TKey key, System.Func<TKey, TArg, TValue> valueFactory, TArg factoryArgument) { throw null; }
+        public TValue GetOrAdd<TArg>(TKey key, System.Func<TKey, TArg, TValue> valueFactory, TArg factoryArgument) where TArg : allows ref struct { throw null; }
         void System.Collections.Generic.ICollection<System.Collections.Generic.KeyValuePair<TKey, TValue>>.Add(System.Collections.Generic.KeyValuePair<TKey, TValue> keyValuePair) { }
         bool System.Collections.Generic.ICollection<System.Collections.Generic.KeyValuePair<TKey, TValue>>.Contains(System.Collections.Generic.KeyValuePair<TKey, TValue> keyValuePair) { throw null; }
         void System.Collections.Generic.ICollection<System.Collections.Generic.KeyValuePair<TKey, TValue>>.CopyTo(System.Collections.Generic.KeyValuePair<TKey, TValue>[] array, int index) { }

src/libraries/System.Collections.Concurrent/src/System/Collections/Concurrent/ConcurrentDictionary.cs

@@ -1201,6 +1201,7 @@ public TValue GetOrAdd(TKey key, Func<TKey, TValue> valueFactory)
         /// key is already in the dictionary, or the new value for the key as returned by valueFactory
         /// if the key was not in the dictionary.</returns>
         public TValue GetOrAdd<TArg>(TKey key, Func<TKey, TArg, TValue> valueFactory, TArg factoryArgument)
+            where TArg : allows ref struct
         {
             if (key is null)
             {
@@ -1279,6 +1280,7 @@ public TValue GetOrAdd(TKey key, TValue value)
         /// absent) or the result of updateValueFactory (if the key was present).</returns>
         public TValue AddOrUpdate<TArg>(
             TKey key, Func<TKey, TArg, TValue> addValueFactory, Func<TKey, TValue, TArg, TValue> updateValueFactory, TArg factoryArgument)
+            where TArg : allows ref struct
         {
             if (key is null)
             {

src/libraries/System.Collections.Immutable/ref/System.Collections.Immutable.cs

@@ -200,8 +200,16 @@ public static partial class ImmutableArray
         public static System.Collections.Immutable.ImmutableArray<T> CreateRange<T>(System.Collections.Generic.IEnumerable<T> items) { throw null; }
         public static System.Collections.Immutable.ImmutableArray<TResult> CreateRange<TSource, TResult>(System.Collections.Immutable.ImmutableArray<TSource> items, System.Func<TSource, TResult> selector) { throw null; }
         public static System.Collections.Immutable.ImmutableArray<TResult> CreateRange<TSource, TResult>(System.Collections.Immutable.ImmutableArray<TSource> items, int start, int length, System.Func<TSource, TResult> selector) { throw null; }
-        public static System.Collections.Immutable.ImmutableArray<TResult> CreateRange<TSource, TArg, TResult>(System.Collections.Immutable.ImmutableArray<TSource> items, System.Func<TSource, TArg, TResult> selector, TArg arg) { throw null; }
-        public static System.Collections.Immutable.ImmutableArray<TResult> CreateRange<TSource, TArg, TResult>(System.Collections.Immutable.ImmutableArray<TSource> items, int start, int length, System.Func<TSource, TArg, TResult> selector, TArg arg) { throw null; }
+        public static System.Collections.Immutable.ImmutableArray<TResult> CreateRange<TSource, TArg, TResult>(System.Collections.Immutable.ImmutableArray<TSource> items, System.Func<TSource, TArg, TResult> selector, TArg arg)
+#if NET9_0_OR_GREATER
+            where TArg : allows ref struct
+#endif
+        { throw null; }
+        public static System.Collections.Immutable.ImmutableArray<TResult> CreateRange<TSource, TArg, TResult>(System.Collections.Immutable.ImmutableArray<TSource> items, int start, int length, System.Func<TSource, TArg, TResult> selector, TArg arg)
+#if NET9_0_OR_GREATER
+            where TArg : allows ref struct
+#endif
+        { throw null; }
         public static System.Collections.Immutable.ImmutableArray<T> Create<T>() { throw null; }
         public static System.Collections.Immutable.ImmutableArray<T> Create<T>(System.Collections.Immutable.ImmutableArray<T> items, int start, int length) { throw null; }
         public static System.Collections.Immutable.ImmutableArray<T> Create<T>(T item) { throw null; }
@@ -672,7 +680,11 @@ public static partial class ImmutableInterlocked
         public static void Enqueue<T>(ref System.Collections.Immutable.ImmutableQueue<T> location, T value) { }
         public static TValue GetOrAdd<TKey, TValue>(ref System.Collections.Immutable.ImmutableDictionary<TKey, TValue> location, TKey key, System.Func<TKey, TValue> valueFactory) where TKey : notnull { throw null; }
         public static TValue GetOrAdd<TKey, TValue>(ref System.Collections.Immutable.ImmutableDictionary<TKey, TValue> location, TKey key, TValue value) where TKey : notnull { throw null; }
-        public static TValue GetOrAdd<TKey, TValue, TArg>(ref System.Collections.Immutable.ImmutableDictionary<TKey, TValue> location, TKey key, System.Func<TKey, TArg, TValue> valueFactory, TArg factoryArgument) where TKey : notnull { throw null; }
+        public static TValue GetOrAdd<TKey, TValue, TArg>(ref System.Collections.Immutable.ImmutableDictionary<TKey, TValue> location, TKey key, System.Func<TKey, TArg, TValue> valueFactory, TArg factoryArgument) where TKey : notnull
+#if NET9_0_OR_GREATER
+            where TArg : allows ref struct
+#endif
+        { throw null; }
         public static System.Collections.Immutable.ImmutableArray<T> InterlockedCompareExchange<T>(ref System.Collections.Immutable.ImmutableArray<T> location, System.Collections.Immutable.ImmutableArray<T> value, System.Collections.Immutable.ImmutableArray<T> comparand) { throw null; }
         public static System.Collections.Immutable.ImmutableArray<T> InterlockedExchange<T>(ref System.Collections.Immutable.ImmutableArray<T> location, System.Collections.Immutable.ImmutableArray<T> value) { throw null; }
         public static bool InterlockedInitialize<T>(ref System.Collections.Immutable.ImmutableArray<T> location, System.Collections.Immutable.ImmutableArray<T> value) { throw null; }
@@ -683,9 +695,17 @@ public static void Push<T>(ref System.Collections.Immutable.ImmutableStack<T> lo
         public static bool TryRemove<TKey, TValue>(ref System.Collections.Immutable.ImmutableDictionary<TKey, TValue> location, TKey key, [System.Diagnostics.CodeAnalysis.MaybeNullWhenAttribute(false)] out TValue value) where TKey : notnull { throw null; }
         public static bool TryUpdate<TKey, TValue>(ref System.Collections.Immutable.ImmutableDictionary<TKey, TValue> location, TKey key, TValue newValue, TValue comparisonValue) where TKey : notnull { throw null; }
         public static bool Update<T>(ref T location, System.Func<T, T> transformer) where T : class? { throw null; }
-        public static bool Update<T, TArg>(ref T location, System.Func<T, TArg, T> transformer, TArg transformerArgument) where T : class? { throw null; }
+        public static bool Update<T, TArg>(ref T location, System.Func<T, TArg, T> transformer, TArg transformerArgument) where T : class?
+#if NET9_0_OR_GREATER
+            where TArg : allows ref struct
+#endif
+        { throw null; }
         public static bool Update<T>(ref System.Collections.Immutable.ImmutableArray<T> location, Func<System.Collections.Immutable.ImmutableArray<T>, System.Collections.Immutable.ImmutableArray<T>> transformer) { throw null; }
-        public static bool Update<T, TArg>(ref System.Collections.Immutable.ImmutableArray<T> location, Func<System.Collections.Immutable.ImmutableArray<T>, TArg, System.Collections.Immutable.ImmutableArray<T>> transformer, TArg transformerArgument) { throw null; }
+        public static bool Update<T, TArg>(ref System.Collections.Immutable.ImmutableArray<T> location, Func<System.Collections.Immutable.ImmutableArray<T>, TArg, System.Collections.Immutable.ImmutableArray<T>> transformer, TArg transformerArgument)
+#if NET9_0_OR_GREATER
+            where TArg : allows ref struct
+#endif
+        { throw null; }
     }
     public static partial class ImmutableList
     {

src/libraries/System.Collections.Immutable/src/System/Collections/Immutable/ImmutableArray.cs

@@ -337,6 +337,9 @@ public static ImmutableArray<TResult> CreateRange<TSource, TResult>(ImmutableArr
         /// the source array.
         /// </remarks>
         public static ImmutableArray<TResult> CreateRange<TSource, TArg, TResult>(ImmutableArray<TSource> items, Func<TSource, TArg, TResult> selector, TArg arg)
+#if NET9_0_OR_GREATER
+            where TArg : allows ref struct
+#endif
         {
             Requires.NotNull(selector, nameof(selector));
 
@@ -370,6 +373,9 @@ public static ImmutableArray<TResult> CreateRange<TSource, TArg, TResult>(Immuta
         /// included in the resulting array.
         /// </remarks>
         public static ImmutableArray<TResult> CreateRange<TSource, TArg, TResult>(ImmutableArray<TSource> items, int start, int length, Func<TSource, TArg, TResult> selector, TArg arg)
+#if NET9_0_OR_GREATER
+            where TArg : allows ref struct
+#endif
         {
             int itemsLength = items.Length;
 

src/libraries/System.Collections.Immutable/src/System/Collections/Immutable/ImmutableInterlocked.cs

@@ -76,6 +76,9 @@ public static bool Update<T>(ref T location, Func<T, T> transformer) where T : c
         /// invocation of <paramref name="transformer"/> returned the existing value.
         /// </returns>
         public static bool Update<T, TArg>(ref T location, Func<T, TArg, T> transformer, TArg transformerArgument) where T : class?
+#if NET9_0_OR_GREATER
+            where TArg : allows ref struct
+#endif
         {
             Requires.NotNull(transformer, nameof(transformer));
 
@@ -162,6 +165,9 @@ public static bool Update<T>(ref ImmutableArray<T> location, Func<ImmutableArray
         /// invocation of <paramref name="transformer"/> returned the existing value.
         /// </returns>
         public static bool Update<T, TArg>(ref ImmutableArray<T> location, Func<ImmutableArray<T>, TArg, ImmutableArray<T>> transformer, TArg transformerArgument)
+#if NET9_0_OR_GREATER
+            where TArg : allows ref struct
+#endif
         {
             Requires.NotNull(transformer, nameof(transformer));
 
@@ -241,7 +247,11 @@ public static bool InterlockedInitialize<T>(ref ImmutableArray<T> location, Immu
         /// <param name="valueFactory">The function to execute to obtain the value to insert into the dictionary if the key is not found.</param>
         /// <param name="factoryArgument">The argument to pass to the value factory.</param>
         /// <returns>The value obtained from the dictionary or <paramref name="valueFactory"/> if it was not present.</returns>
-        public static TValue GetOrAdd<TKey, TValue, TArg>(ref ImmutableDictionary<TKey, TValue> location, TKey key, Func<TKey, TArg, TValue> valueFactory, TArg factoryArgument) where TKey : notnull
+        public static TValue GetOrAdd<TKey, TValue, TArg>(ref ImmutableDictionary<TKey, TValue> location, TKey key, Func<TKey, TArg, TValue> valueFactory, TArg factoryArgument)
+            where TKey : notnull
+#if NET9_0_OR_GREATER
+            where TArg : allows ref struct
+#endif
         {
             Requires.NotNull(valueFactory, nameof(valueFactory));
 

src/libraries/System.Linq/src/System/Linq/Sum.cs

@@ -60,11 +60,11 @@ private static TResult Sum<T, TResult>(ReadOnlySpan<T> span)
 
                 if (typeof(T) == typeof(long))
                 {
-                    return (TResult)(object)SumSignedIntegersVectorized(MemoryMarshal.Cast<T, long>(span));
+                    return (TResult)(object)SumSignedIntegersVectorized(Unsafe.BitCast<ReadOnlySpan<T>, ReadOnlySpan<long>>(span));
                 }
                 if (typeof(T) == typeof(int))
                 {
-                    return (TResult)(object)SumSignedIntegersVectorized(MemoryMarshal.Cast<T, int>(span));
+                    return (TResult)(object)SumSignedIntegersVectorized(Unsafe.BitCast<ReadOnlySpan<T>, ReadOnlySpan<int>>(span));
                 }
             }
 

src/libraries/System.Numerics.Tensors/src/System/Numerics/Tensors/TensorPrimitives.Helpers.cs

@@ -36,7 +36,11 @@ private static void ValidateInputOutputSpanNonOverlapping<T>(ReadOnlySpan<T> inp
         private static unsafe Span<TTo> Rename<TFrom, TTo>(Span<TFrom> span)
         {
             Debug.Assert(sizeof(TFrom) == sizeof(TTo));
+#if NET9_0_OR_GREATER
+            return Unsafe.BitCast<Span<TFrom>, Span<TTo>>(span);
+#else
             return *(Span<TTo>*)(&span);
+#endif
         }
 
         /// <summary>Creates a span of <typeparamref name="TTo"/> from a <typeparamref name="TFrom"/> when they're the same type.</summary>
@@ -48,7 +52,11 @@ private static unsafe Span<TTo> Rename<TFrom, TTo>(Span<TFrom> span)
         private static unsafe ReadOnlySpan<TTo> Rename<TFrom, TTo>(ReadOnlySpan<TFrom> span)
         {
             Debug.Assert(sizeof(TFrom) == sizeof(TTo));
+#if NET9_0_OR_GREATER
+            return Unsafe.BitCast<ReadOnlySpan<TFrom>, ReadOnlySpan<TTo>>(span);
+#else
             return *(ReadOnlySpan<TTo>*)(&span);
+#endif
         }
 
         /// <summary>Mask used to handle alignment elements before vectorized handling of the input.</summary>