Vulkan: Feedback loop detection and barriers (#7226)

* Vulkan: Feedback loop improvements

This PR allows the Vulkan backend to detect attachment feedback loops. These are currently used in the following ways:

- Partial use of VK_EXT_attachment_feedback_loop_layout
  - All renderable textures have AttachmentFeedbackLoopBitExt
  - Compile pipelines with Color/DepthStencil feedback loop flags when present
- Support using FragmentBarrier for feedback loops (fixes regressions from https://github.com/Ryujinx/Ryujinx/pull/7012 )

TODO:
- AMD GPUs may need layout transitions for it to properly allow textures to be used in feedback loops.
- Use dynamic state for feedback loops. The background pipeline will always miss since feedback loop state isn't known on the GPU project.
- How is the barrier dependency flag used? (DXVK just ignores it, there's no vulkan validation...)
- Improve subpass dependencies to fix validation errors

* Mark field readonly

* Add feedback loop dynamic state

* fix: add MoltenVK resolver workaround

fix: add MoltenVK resolver workaround

* Formatting

* Fix more complaints

* RADV dcc workaround

* Use dynamic state properly, cleanup.

* Use aspects flags in more places

src/Ryujinx.Common/GraphicsDriver/DriverUtilities.cs

@@ -1,13 +1,33 @@
+using Ryujinx.Common.Utilities;
 using System;
 
 namespace Ryujinx.Common.GraphicsDriver
 {
     public static class DriverUtilities
     {
+        private static void AddMesaFlags(string envVar, string newFlags)
+        {
+            string existingFlags = Environment.GetEnvironmentVariable(envVar);
+
+            string flags = existingFlags == null ? newFlags : $"{existingFlags},{newFlags}";
+
+            OsUtils.SetEnvironmentVariableNoCaching(envVar, flags);
+        }
+
+        public static void InitDriverConfig(bool oglThreading)
+        {
+            if (OperatingSystem.IsLinux())
+            {
+                AddMesaFlags("RADV_DEBUG", "nodcc");
+            }
+
+            ToggleOGLThreading(oglThreading);
+        }
+
         public static void ToggleOGLThreading(bool enabled)
         {
-            Environment.SetEnvironmentVariable("mesa_glthread", enabled.ToString().ToLower());
-            Environment.SetEnvironmentVariable("__GL_THREADED_OPTIMIZATIONS", enabled ? "1" : "0");
+            OsUtils.SetEnvironmentVariableNoCaching("mesa_glthread", enabled.ToString().ToLower());
+            OsUtils.SetEnvironmentVariableNoCaching("__GL_THREADED_OPTIMIZATIONS", enabled ? "1" : "0");
 
             try
             {

src/Ryujinx.Common/Utilities/OsUtils.cs

@@ -0,0 +1,24 @@
+using System;
+using System.Diagnostics;
+using System.Runtime.InteropServices;
+
+namespace Ryujinx.Common.Utilities
+{
+    public partial class OsUtils
+    {
+        [LibraryImport("libc", SetLastError = true)]
+        private static partial int setenv([MarshalAs(UnmanagedType.LPStr)] string name, [MarshalAs(UnmanagedType.LPStr)] string value, int overwrite);
+
+        public static void SetEnvironmentVariableNoCaching(string key, string value)
+        {
+            // Set the value in the cached environment variables, too.
+            Environment.SetEnvironmentVariable(key, value);
+
+            if (!OperatingSystem.IsWindows())
+            {
+                int res = setenv(key, value, 1);
+                Debug.Assert(res != -1);
+            }
+        }
+    }
+}