gl_shader_cache: Use dirty flags for shaders

src/video_core/renderer_opengl/gl_rasterizer.cpp

@@ -293,7 +293,7 @@ DrawParameters RasterizerOpenGL::SetupDraw() {
 
 void RasterizerOpenGL::SetupShaders(GLenum primitive_mode) {
     MICROPROFILE_SCOPE(OpenGL_Shader);
-    const auto& gpu = Core::System::GetInstance().GPU().Maxwell3D();
+    auto& gpu = Core::System::GetInstance().GPU().Maxwell3D();
 
     // Next available bindpoints to use when uploading the const buffers and textures to the GLSL
     // shaders. The constbuffer bindpoint starts after the shader stage configuration bind points.
@@ -376,6 +376,8 @@ void RasterizerOpenGL::SetupShaders(GLenum primitive_mode) {
     }
 
     SyncClipEnabled(clip_distances);
+
+    gpu.dirty_flags.shaders = false;
 }
 
 void RasterizerOpenGL::SetupCachedFramebuffer(const FramebufferCacheKey& fbkey,

src/video_core/renderer_opengl/gl_shader_cache.cpp

@@ -188,6 +188,10 @@ void CachedShader::CalculateProperties() {
 ShaderCacheOpenGL::ShaderCacheOpenGL(RasterizerOpenGL& rasterizer) : RasterizerCache{rasterizer} {}
 
 Shader ShaderCacheOpenGL::GetStageProgram(Maxwell::ShaderProgram program) {
+    if (!Core::System::GetInstance().GPU().Maxwell3D().dirty_flags.shaders) {
+        return last_shaders[static_cast<u32>(program)];
+    }
+
     const VAddr program_addr{GetShaderAddress(program)};
 
     // Look up shader in the cache based on address
@@ -199,7 +203,7 @@ Shader ShaderCacheOpenGL::GetStageProgram(Maxwell::ShaderProgram program) {
         Register(shader);
     }
 
-    return shader;
+    return last_shaders[static_cast<u32>(program)] = shader;
 }
 
 } // namespace OpenGL

src/video_core/renderer_opengl/gl_shader_cache.h

@@ -4,6 +4,7 @@
 
 #pragma once
 
+#include <array>
 #include <map>
 #include <memory>
 
@@ -115,6 +116,9 @@ public:
 
     /// Gets the current specified shader stage program
     Shader GetStageProgram(Maxwell::ShaderProgram program);
+
+private:
+    std::array<Shader, Maxwell::MaxShaderProgram> last_shaders;
 };
 
 } // namespace OpenGL