Replace most corelib uses of Unsafe.SizeOf<T> with sizeof(T) (#104923)

Also suppress CS8500 globally rather than in hundreds of files individually and fix NoWarns that weren't inheriting global NoWarns.

Author: stephentoub

Directory.Build.props

@@ -388,7 +388,7 @@
     <Features>strict;nullablePublicOnly</Features>
     <TreatWarningsAsErrors Condition="'$(TreatWarningsAsErrors)' == ''">true</TreatWarningsAsErrors>
     <!-- Warnings to always disable -->
-    <NoWarn>$(NoWarn),CS8969</NoWarn>
+    <NoWarn>$(NoWarn);CS8500;CS8969</NoWarn>
     <!-- Always pass portable to override arcade sdk which uses embedded for local builds -->
     <DebugType>portable</DebugType>
     <KeepNativeSymbols Condition="'$(KeepNativeSymbols)' == '' and '$(DotNetBuildSourceOnly)' == 'true'">true</KeepNativeSymbols>

src/coreclr/System.Private.CoreLib/src/System/ArgIterator.cs

@@ -58,7 +58,6 @@ public ArgIterator(RuntimeArgumentHandle arglist, void* ptr)
         [LibraryImport(RuntimeHelpers.QCall, EntryPoint = "ArgIterator_Init2")]
         private static partial void Init(ArgIterator* thisPtr, IntPtr cookie, void* ptr);
 
-#pragma warning disable CS8500 // Takes a pointer to a managed type
         // Fetch an argument as a typed referece, advance the iterator.
         // Throws an exception if past end of argument list
         [CLSCompliant(false)]

src/coreclr/System.Private.CoreLib/src/System/GC.CoreCLR.cs

@@ -790,9 +790,7 @@ public static unsafe T[] AllocateUninitializedArray<T>(int length, bool pinned =
                 // for debug builds we always want to call AllocateNewArray to detect AllocateNewArray bugs
 #if !DEBUG
                 // small arrays are allocated using `new[]` as that is generally faster.
-#pragma warning disable 8500 // sizeof of managed types
                 if (length < 2048 / sizeof(T))
-#pragma warning restore 8500
                 {
                     return new T[length];
                 }
@@ -892,9 +890,7 @@ public static unsafe IReadOnlyDictionary<string, object> GetConfigurationVariabl
                 Configurations = new Dictionary<string, object>()
             };
 
-#pragma warning disable CS8500 // takes address of managed type
             _EnumerateConfigurationValues(&context, &ConfigCallback);
-#pragma warning restore CS8500
             return context.Configurations!;
         }
 

src/coreclr/System.Private.CoreLib/src/System/Reflection/RtFieldInfo.cs

@@ -93,9 +93,7 @@ public override int GetHashCode() =>
                 throw new ArgumentException(SR.Arg_TypedReference_Null);
 
             // Passing TypedReference by reference is easier to make correct in native code
-#pragma warning disable CS8500 // Takes a pointer to a managed type
             return RuntimeFieldHandle.GetValueDirect(this, (RuntimeType)FieldType, &obj, (RuntimeType?)DeclaringType);
-#pragma warning restore CS8500
         }
 
         [DebuggerStepThrough]
@@ -111,9 +109,7 @@ public override void SetValueDirect(TypedReference obj, object value)
                 throw new ArgumentException(SR.Arg_TypedReference_Null);
 
             // Passing TypedReference by reference is easier to make correct in native code
-#pragma warning disable CS8500 // Takes a pointer to a managed type
             RuntimeFieldHandle.SetValueDirect(this, (RuntimeType)FieldType, &obj, value, (RuntimeType?)DeclaringType);
-#pragma warning restore CS8500
         }
 
         public override RuntimeFieldHandle FieldHandle => new RuntimeFieldHandle(this);

src/coreclr/System.Private.CoreLib/src/System/Runtime/DependentHandle.cs

@@ -253,9 +253,7 @@ private static IntPtr InternalAllocWithGCTransition(object? target, object? depe
         // This optimization is the same that is used in GCHandle in RELEASE mode.
         // This is not used in DEBUG builds as the runtime performs additional checks.
         // The logic below is the inlined copy of ObjectFromHandle in the unmanaged runtime.
-#pragma warning disable 8500 // address of managed types
         private static unsafe object? InternalGetTarget(IntPtr dependentHandle) => *(object*)dependentHandle;
-#pragma warning restore 8500
 #endif
 
         [MethodImpl(MethodImplOptions.InternalCall)]

src/coreclr/System.Private.CoreLib/src/System/Runtime/ExceptionServices/InternalCalls.cs

@@ -23,7 +23,6 @@ internal static partial class InternalCalls
         [LibraryImport(RuntimeHelpers.QCall, EntryPoint = "ResumeAtInterceptionLocation")]
         internal static unsafe partial void ResumeAtInterceptionLocation(void* pvRegDisplay);
 
-#pragma warning disable CS8500
         [LibraryImport(RuntimeHelpers.QCall, EntryPoint = "CallCatchFunclet")]
         internal static unsafe partial IntPtr RhpCallCatchFunclet(
             ObjectHandleOnStack exceptionObj, byte* pHandlerIP, void* pvRegDisplay, EH.ExInfo* exInfo);
@@ -38,7 +37,6 @@ internal static unsafe partial bool RhpCallFilterFunclet(
 
         [LibraryImport(RuntimeHelpers.QCall, EntryPoint = "AppendExceptionStackFrame")]
         internal static unsafe partial void RhpAppendExceptionStackFrame(ObjectHandleOnStack exceptionObj, IntPtr ip, UIntPtr sp, int flags, EH.ExInfo* exInfo);
-#pragma warning restore CS8500
 
         [LibraryImport(RuntimeHelpers.QCall, EntryPoint = "EHEnumInitFromStackFrameIterator")]
         [return: MarshalAs(UnmanagedType.Bool)]

src/coreclr/System.Private.CoreLib/src/System/Runtime/InteropServices/GCHandle.CoreCLR.cs

@@ -46,9 +46,7 @@ private static void InternalFreeWithGCTransition(IntPtr dependentHandle)
         [MethodImpl(MethodImplOptions.InternalCall)]
         internal static extern object? InternalGet(IntPtr handle);
 #else
-#pragma warning disable 8500 // address of managed types
         internal static unsafe object? InternalGet(IntPtr handle) => *(object*)handle;
-#pragma warning restore 8500
 #endif
 
         [MethodImpl(MethodImplOptions.InternalCall)]

src/coreclr/nativeaot/Common/src/Internal/Runtime/CompilerHelpers/StartupCodeHelpers.cs

@@ -206,7 +206,6 @@ private static unsafe object[] InitializeStatics(IntPtr gcStaticRegionStart, int
                 nint blockAddr = MethodTable.SupportsRelativePointers ? (nint)ReadRelPtr32(pBlock) : *pBlock;
                 if ((blockAddr & GCStaticRegionConstants.Uninitialized) == GCStaticRegionConstants.Uninitialized)
                 {
-#pragma warning disable CS8500 // takes address of managed type
                     object? obj = null;
                     RuntimeImports.RhAllocateNewObject(
                         new IntPtr(blockAddr & ~GCStaticRegionConstants.Mask),
@@ -234,7 +233,6 @@ private static unsafe object[] InitializeStatics(IntPtr gcStaticRegionStart, int
 
                     // Update the base pointer to point to the pinned object
                     *pBlock = *(IntPtr*)&obj;
-#pragma warning restore CS8500
                 }
 
                 currentBase++;

src/coreclr/nativeaot/Runtime.Base/src/System/Runtime/CachedInterfaceDispatch.cs

@@ -15,9 +15,7 @@ internal static unsafe class CachedInterfaceDispatch
         private static unsafe IntPtr RhpCidResolve(IntPtr callerTransitionBlockParam, IntPtr pCell)
         {
             IntPtr locationOfThisPointer = callerTransitionBlockParam + TransitionBlock.GetThisOffset();
-#pragma warning disable 8500 // address of managed types
             object pObject = *(object*)locationOfThisPointer;
-#pragma warning restore 8500
             IntPtr dispatchResolveTarget = RhpCidResolve_Worker(pObject, pCell);
             return dispatchResolveTarget;
         }

src/coreclr/nativeaot/Runtime.Base/src/System/Runtime/ExceptionHandling.cs

@@ -279,12 +279,11 @@ private static void AppendExceptionStackFrameViaClasslib(object exception, IntPt
                 isFirstFrame = false;
             }
 #else
-#pragma warning disable CS8500
             fixed (EH.ExInfo* pExInfo = &exInfo)
             {
                 InternalCalls.RhpAppendExceptionStackFrame(ObjectHandleOnStack.Create(ref exception), ip, sp, flags, pExInfo);
             }
-#pragma warning restore CS8500
+
             // Clear flags only if we called the function
             isFirstRethrowFrame = false;
             isFirstFrame = false;
@@ -686,13 +685,11 @@ public static void RhUnwindAndIntercept(ref ExInfo exInfo, UIntPtr interceptStac
             if (unwoundReversePInvoke)
             {
                 object exceptionObj = exInfo.ThrownException;
-#pragma warning disable CS8500
                 fixed (EH.ExInfo* pExInfo = &exInfo)
                 {
                     InternalCalls.RhpCallCatchFunclet(
                         ObjectHandleOnStack.Create(ref exceptionObj), null, exInfo._frameIter.RegisterSet, pExInfo);
                 }
-#pragma warning restore CS8500
             }
             else
             {
@@ -922,13 +919,11 @@ private static void DispatchEx(scoped ref StackFrameIterator frameIter, ref ExIn
             InternalCalls.RhpCallCatchFunclet(
                 exceptionObj, pCatchHandler, frameIter.RegisterSet, ref exInfo);
 #else // NATIVEAOT
-#pragma warning disable CS8500
             fixed (EH.ExInfo* pExInfo = &exInfo)
             {
                 InternalCalls.RhpCallCatchFunclet(
                     ObjectHandleOnStack.Create(ref exceptionObj), pCatchHandler, frameIter.RegisterSet, pExInfo);
             }
-#pragma warning restore CS8500
 #endif // NATIVEAOT
             // currently, RhpCallCatchFunclet will resume after the catch
             Debug.Assert(false, "unreachable");
@@ -1209,12 +1204,10 @@ private static void InvokeSecondPass(ref ExInfo exInfo, uint idxStart, uint idxL
 #if NATIVEAOT
                 InternalCalls.RhpCallFinallyFunclet(pFinallyHandler, exInfo._frameIter.RegisterSet);
 #else // NATIVEAOT
-#pragma warning disable CS8500
                 fixed (EH.ExInfo* pExInfo = &exInfo)
                 {
                     InternalCalls.RhpCallFinallyFunclet(pFinallyHandler, exInfo._frameIter.RegisterSet, pExInfo);
                 }
-#pragma warning restore CS8500
 #endif // NATIVEAOT
                 exInfo._idxCurClause = MaxTryRegionIdx;
             }