rasterizer_cache: Reintroduce method for flushing.

src/video_core/rasterizer_cache.h

@@ -17,6 +17,22 @@
 template <class T>
 class RasterizerCache : NonCopyable {
 public:
+    /// Write any cached resources overlapping the region back to memory (if dirty)
+    void FlushRegion(Tegra::GPUVAddr addr, size_t size) {
+        if (size == 0)
+            return;
+
+        const ObjectInterval interval{addr, addr + size};
+        for (auto& pair : boost::make_iterator_range(object_cache.equal_range(interval))) {
+            for (auto& cached_object : pair.second) {
+                if (!cached_object)
+                    continue;
+
+                cached_object->Flush();
+            }
+        }
+    }
+
     /// Mark the specified region as being invalidated
     void InvalidateRegion(VAddr addr, u64 size) {
         if (size == 0)
@@ -71,6 +87,7 @@ protected:
     void Unregister(const T& object) {
         auto& rasterizer = Core::System::GetInstance().Renderer().Rasterizer();
         rasterizer.UpdatePagesCachedCount(object->GetAddr(), object->GetSizeInBytes(), -1);
+        object->Flush();
         object_cache.subtract({GetInterval(object), ObjectSet{object}});
     }
 

src/video_core/renderer_opengl/gl_buffer_cache.h

@@ -24,6 +24,9 @@ struct CachedBufferEntry final {
         return size;
     }
 
+    // We do not have to flush this cache as things in it are never modified by us.
+    void Flush() {}
+
     VAddr addr;
     std::size_t size;
     GLintptr offset;

src/video_core/renderer_opengl/gl_shader_cache.h

@@ -33,6 +33,9 @@ public:
         return GLShader::MAX_PROGRAM_CODE_LENGTH * sizeof(u64);
     }
 
+    // We do not have to flush this cache as things in it are never modified by us.
+    void Flush() {}
+
     /// Gets the shader entries for the shader
     const GLShader::ShaderEntries& GetShaderEntries() const {
         return entries;