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Diffstat (limited to 'src/mscorlib/src/System/Runtime/CompilerServices/AsyncMethodBuilder.cs')
-rw-r--r--src/mscorlib/src/System/Runtime/CompilerServices/AsyncMethodBuilder.cs60
1 files changed, 6 insertions, 54 deletions
diff --git a/src/mscorlib/src/System/Runtime/CompilerServices/AsyncMethodBuilder.cs b/src/mscorlib/src/System/Runtime/CompilerServices/AsyncMethodBuilder.cs
index 6a16462383..afb0c22778 100644
--- a/src/mscorlib/src/System/Runtime/CompilerServices/AsyncMethodBuilder.cs
+++ b/src/mscorlib/src/System/Runtime/CompilerServices/AsyncMethodBuilder.cs
@@ -18,7 +18,6 @@ using System.Diagnostics.CodeAnalysis;
using System.Diagnostics.Contracts;
using System.Runtime.ExceptionServices;
using System.Security;
-using System.Security.Permissions;
using System.Threading;
using System.Threading.Tasks;
@@ -840,36 +839,6 @@ namespace System.Runtime.CompilerServices
// This method is copy&pasted into the public Start methods to avoid size overhead of valuetype generic instantiations.
// Ideally, we would build intrinsics to get the raw ref address and raw code address of MoveNext, and just use the shared implementation.
-#if false
- /// <summary>Initiates the builder's execution with the associated state machine.</summary>
- /// <typeparam name="TStateMachine">Specifies the type of the state machine.</typeparam>
- /// <param name="stateMachine">The state machine instance, passed by reference.</param>
- /// <exception cref="System.ArgumentNullException">The <paramref name="stateMachine"/> argument is null (Nothing in Visual Basic).</exception>
- [DebuggerStepThrough]
- internal static void Start<TStateMachine>(ref TStateMachine stateMachine)
- where TStateMachine : IAsyncStateMachine
- {
- if (stateMachine == null) throw new ArgumentNullException(nameof(stateMachine));
- Contract.EndContractBlock();
-
- // Run the MoveNext method within a copy-on-write ExecutionContext scope.
- // This allows us to undo any ExecutionContext changes made in MoveNext,
- // so that they won't "leak" out of the first await.
-
- Thread currentThread = Thread.CurrentThread;
- ExecutionContextSwitcher ecs = default(ExecutionContextSwitcher);
- RuntimeHelpers.PrepareConstrainedRegions();
- try
- {
- ExecutionContext.EstablishCopyOnWriteScope(currentThread, ref ecs);
- stateMachine.MoveNext();
- }
- finally
- {
- ecs.Undo(currentThread);
- }
- }
-#endif
/// <summary>Associates the builder with the state machine it represents.</summary>
/// <param name="stateMachine">The heap-allocated state machine object.</param>
@@ -906,12 +875,12 @@ namespace System.Runtime.CompilerServices
Debugger.NotifyOfCrossThreadDependency();
// The builder needs to flow ExecutionContext, so capture it.
- var capturedContext = ExecutionContext.FastCapture(); // ok to use FastCapture as we haven't made any permission demands/asserts
+ var capturedContext = ExecutionContext.Capture();
// If the ExecutionContext is the default context, try to use a cached delegate, creating one if necessary.
Action action;
MoveNextRunner runner;
- if (capturedContext != null && capturedContext.IsPreAllocatedDefault)
+ if (capturedContext == ExecutionContext.Default)
{
// Get the cached delegate, and if it's non-null, return it.
action = m_defaultContextAction;
@@ -1046,12 +1015,8 @@ namespace System.Runtime.CompilerServices
if (m_context != null)
{
- try
- {
- // Use the context and callback to invoke m_stateMachine.MoveNext.
- ExecutionContext.Run(m_context, InvokeMoveNextCallback, m_stateMachine, preserveSyncCtx: true);
- }
- finally { m_context.Dispose(); }
+ // Use the context and callback to invoke m_stateMachine.MoveNext.
+ ExecutionContext.Run(m_context, InvokeMoveNextCallback, m_stateMachine);
}
else
{
@@ -1076,24 +1041,11 @@ namespace System.Runtime.CompilerServices
internal void RunWithDefaultContext()
{
Debug.Assert(m_stateMachine != null, "The state machine must have been set before calling Run.");
- ExecutionContext.Run(ExecutionContext.PreAllocatedDefault, InvokeMoveNextCallback, m_stateMachine, preserveSyncCtx: true);
+ ExecutionContext.Run(ExecutionContext.Default, InvokeMoveNextCallback, m_stateMachine);
}
/// <summary>Gets a delegate to the InvokeMoveNext method.</summary>
- protected static ContextCallback InvokeMoveNextCallback
- {
- get { return s_invokeMoveNext ?? (s_invokeMoveNext = InvokeMoveNext); }
- }
-
- /// <summary>Cached delegate used with ExecutionContext.Run.</summary>
- private static ContextCallback s_invokeMoveNext; // lazily-initialized due to SecurityCritical attribution
-
- /// <summary>Invokes the MoveNext method on the supplied IAsyncStateMachine.</summary>
- /// <param name="stateMachine">The IAsyncStateMachine machine instance.</param>
- private static void InvokeMoveNext(object stateMachine)
- {
- ((IAsyncStateMachine)stateMachine).MoveNext();
- }
+ protected static readonly ContextCallback InvokeMoveNextCallback = sm => ((IAsyncStateMachine)sm).MoveNext();
}
/// <summary>