Merge 7483a08d6a into 658afb8717

src/iOS/Avalonia.iOS/DispatcherImpl.cs

@@ -22,7 +22,8 @@ internal class DispatcherImpl : IDispatcherImplWithExplicitBackgroundProcessing
     private readonly IntPtr _mainLoop;
     private readonly IntPtr _mainQueue;
     private Thread? _loopThread;
-    private bool _backgroundProcessingRequested, _signaled;
+    private bool _backgroundProcessingRequested;
+    private int _signaled;
 
     private unsafe DispatcherImpl()
     {
@@ -60,15 +61,12 @@ internal class DispatcherImpl : IDispatcherImplWithExplicitBackgroundProcessing
 
     public unsafe void Signal()
     {
-        lock (_sync)
+        if (Interlocked.CompareExchange(ref _signaled, 1, 0) != 0)
         {
-            if (_signaled)
-                return;
-            _signaled = true;
-
-            Interop.dispatch_async_f(_mainQueue, IntPtr.Zero, &CheckSignaled);
-            Interop.CFRunLoopWakeUp(_mainLoop);
+            return;
         }
+        Interop.dispatch_async_f(_mainQueue, IntPtr.Zero, &CheckSignaled);
+        Interop.CFRunLoopWakeUp(_mainLoop);
     }
 
     public void UpdateTimer(long? dueTimeInMs)
@@ -91,14 +89,7 @@ internal class DispatcherImpl : IDispatcherImplWithExplicitBackgroundProcessing
 
     private void CheckSignaled()
     {
-        bool signaled;
-        lock (_sync)
-        {
-            signaled = _signaled;
-            _signaled = false;
-        }
-
-        if (signaled)
+        if (Interlocked.Exchange(ref _signaled, 0) != 0)
         {
             Signaled?.Invoke();
         }

src/iOS/Avalonia.iOS/InputHandler.cs

@@ -308,7 +308,7 @@ internal sealed class InputHandler
         
         _tl.Input?.Invoke(new RawMouseWheelEventArgs(
             _mouseDevice, 
-            (ulong)(DateTimeOffset.UtcNow.ToUnixTimeMilliseconds()), 
+            (ulong)Environment.TickCount64, 
             Root,
             _cachedScrollLocation ?? new Point(0, 0),
             new Vector(deltaX, deltaY),
@@ -372,7 +372,7 @@ internal sealed class InputHandler
         // until the inertia stops.
         _tl.Input?.Invoke(new RawMouseWheelEventArgs(
             _mouseDevice, 
-            (ulong)(DateTimeOffset.UtcNow.ToUnixTimeMilliseconds()), 
+            (ulong)Environment.TickCount64, 
             Root,
             _cachedScrollLocation.Value,
             new Vector(_momentumVelocityX, _momentumVelocityY),

src/iOS/Avalonia.iOS/TextInputResponder.cs

@@ -84,6 +84,7 @@ partial class AvaloniaView
         private int _inSurroundingTextUpdateEvent;
         private readonly UITextPosition _beginningOfDocument = new AvaloniaTextPosition(0);
         private readonly UITextInputStringTokenizer _tokenizer;
+        private readonly NSString _textInputContextIdentifier = new NSString(Guid.NewGuid().ToString());
         private bool _isInUpdate;
 
         public TextInputMethodClient? Client => _client;
@@ -95,7 +96,7 @@ partial class AvaloniaView
         public override UIEditingInteractionConfiguration EditingInteractionConfiguration =>
             UIEditingInteractionConfiguration.Default;
 
-        public override NSString TextInputContextIdentifier => new NSString(Guid.NewGuid().ToString());
+        public override NSString TextInputContextIdentifier => _textInputContextIdentifier;
 
         public override UITextInputMode TextInputMode
         {

tests/Avalonia.Benchmarks/Rendering/iOSRenderingBenchmarks.cs

@@ -0,0 +1,42 @@
+#nullable enable
+using System;
+using BenchmarkDotNet.Attributes;
+
+namespace Avalonia.Benchmarks.Rendering
+{
+    /// <summary>
+    /// Benchmarks for Avalonia.iOS hot path patterns.
+    /// Run with: dotnet run -c Release -- --filter *iOSRenderingBenchmarks*
+    /// </summary>
+    [MemoryDiagnoser]
+    public class iOSRenderingBenchmarks
+    {
+        private const int FrameCount = 1000;
+
+        // iOS TextInputContextIdentifier: new Guid+string+wrapper vs cached (TextInputResponder.cs)
+
+        [Benchmark]
+        public string? Current_TextInputContextId_NewGuidPerAccess()
+        {
+            string? last = null;
+            for (int i = 0; i < FrameCount; i++)
+            {
+                last = Guid.NewGuid().ToString();
+            }
+            return last;
+        }
+
+        [Benchmark]
+        public string? Optimized_TextInputContextId_Cached()
+        {
+            string cached = Guid.NewGuid().ToString();
+            string? last = null;
+            for (int i = 0; i < FrameCount; i++)
+            {
+                last = cached;
+            }
+            return last;
+        }
+
+    }
+}