[Diagnostics] Summarize synchronized table reads and trace several writer addresses

SHARPEMU_TRACE_GPU_READS=1 now also reports, every five seconds, the guest
words resource planning read through a GPU synchronization: read count, how
often the value changed, and the first and last value. SHARPEMU_TRACE_WRITER_ADDRESS
accepts a comma-separated list.

src/SharpEmu.Libs/Diagnostics/DccWriterTrace.cs

@@ -9,15 +9,19 @@ namespace SharpEmu.Libs.Diagnostics;
 
 internal static class DccWriterTrace
 {
-    private const int MaxReports = 64;
+    private const int MaxReports = 256;
     private const int MaxFrames = 12;
 
     private static readonly bool DccEnabled =
         Environment.GetEnvironmentVariable("SHARPEMU_TRACE_DCC_WRITERS") == "1";
 
-    private static readonly ulong TargetAddress = ParseAddress(Environment.GetEnvironmentVariable("SHARPEMU_TRACE_WRITER_ADDRESS"));
+    private static readonly ulong[] TargetAddresses = (Environment.GetEnvironmentVariable("SHARPEMU_TRACE_WRITER_ADDRESS") ?? string.Empty)
+        .Split(',', StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries)
+        .Select(ParseAddress)
+        .Where(address => address != 0)
+        .ToArray();
 
-    public static readonly bool Enabled = DccEnabled || TargetAddress != 0;
+    public static readonly bool Enabled = DccEnabled || TargetAddresses.Length != 0;
 
     [ThreadStatic]
     public static ulong CurrentProgram;
@@ -43,7 +47,7 @@ internal static class DccWriterTrace
 
     public static void Record(IGuestImageCache images, ulong address, ulong size)
     {
-        var targeted = TargetAddress != 0 && TargetAddress >= address && TargetAddress - address < size;
+        var targeted = TargetAddresses.Any(target => target >= address && target - address < size);
         if (_reported.Count >= MaxReports || (!targeted && !(DccEnabled && images.OverlapsDccMetadata(address, size))) ||
             !_reported.Add((address, size, CurrentProgram)))
         {

src/SharpEmu.Libs/Diagnostics/GpuReadTrace.cs

@@ -17,6 +17,30 @@ internal static class GpuReadTrace
     public static string? CurrentStage;
 
     private static readonly HashSet<(ulong Shader, ulong Page, bool Table)> _reported = new();
+    private static readonly Dictionary<ulong, (long Reads, long Changes, uint Last, uint First, ulong Shader)> _values = new();
+    private static long _nextValueReport = System.Diagnostics.Stopwatch.GetTimestamp();
+
+    public static void RecordValue(ulong address, uint word)
+    {
+        lock (_values)
+        {
+            _values[address] = _values.TryGetValue(address, out var entry)
+                ? (entry.Reads + 1, entry.Changes + (entry.Last != word ? 1 : 0), word, entry.First, entry.Shader)
+                : (1, 0, word, word, CurrentShader);
+            var now = System.Diagnostics.Stopwatch.GetTimestamp();
+            if (now < _nextValueReport)
+            {
+                return;
+            }
+
+            _nextValueReport = now + System.Diagnostics.Stopwatch.Frequency * 5;
+            foreach (var (key, value) in _values.OrderByDescending(pair => pair.Value.Reads).Take(16))
+            {
+                Console.Error.WriteLine(
+                    $"[GPU][SYNC_READ_VALUE] address=0x{key:X16} reads={value.Reads} changes={value.Changes} first=0x{value.First:X8} last=0x{value.Last:X8} shader=0x{value.Shader:X16}");
+            }
+        }
+    }
 
     public static void Record(ulong address, bool table)
     {

src/SharpEmu.Libs/VideoOut/VulkanVideoPresenter.Pipelines.cs

@@ -100,6 +100,7 @@ internal static unsafe partial class VulkanVideoPresenter
         {
             using var profile = ResourceMaterializationProfile.Measure(ResourceMaterializationProfile.Phase.GuestRead);
             word = 0;
+            var synchronized = false;
             if (IsCleanReadPage(address, sizeof(uint)))
             {
                 if (TryGetAliasPointer(address, sizeof(uint), out var alias))
@@ -132,6 +133,8 @@ internal static unsafe partial class VulkanVideoPresenter
                     {
                         return false;
                     }
+
+                    synchronized = true;
                 }
                 else
                 {
@@ -146,6 +149,11 @@ internal static unsafe partial class VulkanVideoPresenter
             }
 
             word = System.Buffers.Binary.BinaryPrimitives.ReadUInt32LittleEndian(bytes);
+            if (Diagnostics.GpuReadTrace.Enabled && synchronized)
+            {
+                Diagnostics.GpuReadTrace.RecordValue(address, word);
+            }
+
             return true;
         }