rsx: Skip framebufferless draws if we have no side-effects

rpcs3/Emu/RSX/Common/bitfield.hpp

@@ -133,7 +133,7 @@ namespace rsx
 			m_data |= mask;
 		}
 
-		bool test(T mask)
+		bool test(T mask) const
 		{
 			return !!(m_data & static_cast<bitmask_type>(mask));
 		}

rpcs3/Emu/RSX/Core/RSXDriverState.h

@@ -36,14 +36,15 @@ namespace rsx
 		rtt_config_dirty              = (1 << 21), // Render target configuration changed
 		rtt_config_contested          = (1 << 22), // Render target configuration is indeterminate
 		rtt_config_valid              = (1 << 23), // Render target configuration is valid
-		rtt_cache_state_dirty         = (1 << 24), // Texture cache state is indeterminate
+		rtt_config_no_attachments     = (1 << 24), // Render target configuration has no attachments
+		rtt_cache_state_dirty         = (1 << 25), // Texture cache state is indeterminate
 
-		xform_instancing_state_dirty  = (1 << 25), // Transform instancing state has changed
+		xform_instancing_state_dirty  = (1 << 26), // Transform instancing state has changed
 
-		zeta_address_is_cyclic        = (1 << 26), // The currently bound Z buffer is active for R/W in a cyclic manner
-		zeta_address_cyclic_barrier   = (1 << 27), // A memory barrier is required to "end" the Z buffer cyclic state
+		zeta_address_is_cyclic        = (1 << 27), // The currently bound Z buffer is active for R/W in a cyclic manner
+		zeta_address_cyclic_barrier   = (1 << 28), // A memory barrier is required to "end" the Z buffer cyclic state
 
-		blend_config_dirty            = (1 << 28), // Blending configuration has been updated. Only matters when programmable blending is in use.
+		blend_config_dirty            = (1 << 29), // Blending configuration has been updated. Only matters when programmable blending is in use.
 
 		// TODO - Should signal that we simply need to do a FP compare before the next draw call and invalidate the ucode if the content has changed.
 		// Marking as dirty to invalidate hot cache also works, it's not like there's tons of barriers per frame anyway.

rpcs3/Emu/RSX/GL/GLDraw.cpp

@@ -929,7 +929,7 @@ void GLGSRender::end()
 {
 	m_profiler.start();
 
-	if (skip_current_frame || !m_graphics_state.test(rsx::rtt_config_valid) || cond_render_ctrl.disable_rendering())
+	if (should_skip_draw())
 	{
 		execute_nop_draw();
 		rsx::thread::end();

rpcs3/Emu/RSX/GL/GLRenderTargets.cpp

@@ -268,8 +268,7 @@ void GLGSRender::init_buffers(rsx::framebuffer_creation_context context, bool /*
 
 	ensure(m_draw_fbo);
 
-	if (!depth_stencil_target &&
-		std::all_of(color_targets.begin(), color_targets.end(), FN(x == GL_NONE)))
+	if (m_graphics_state.test(rsx::rtt_config_no_attachments))
 	{
 		// Framebufferless rendering. Raster dimensions must be supplied explicitly and match what real surfaces would have used.
 		const auto [raster_width, raster_height] = rsx::apply_resolution_scale<true>(

rpcs3/Emu/RSX/RSXThread.cpp

@@ -1005,6 +1005,22 @@ namespace rsx
 		while (method_registers.current_draw_clause.next());
 	}
 
+	bool thread::should_skip_draw() const
+	{
+		if (skip_current_frame || !m_graphics_state.test(rsx::rtt_config_valid) || cond_render_ctrl.disable_rendering())
+		{
+			return true;
+		}
+
+		if (m_graphics_state.test(rsx::rtt_config_no_attachments) &&
+			(g_cfg.video.disable_zcull_queries || !zcull_ctrl->has_active_queries()))
+		{
+			return true;
+		}
+
+		return false;
+	}
+
 	void thread::cpu_task()
 	{
 		while (Emu.IsReady())
@@ -1461,7 +1477,7 @@ namespace rsx
 		layout.width = rsx::method_registers.surface_clip_width();
 		layout.height = rsx::method_registers.surface_clip_height();
 
-		m_graphics_state.clear(rsx::rtt_config_contested | rsx::rtt_config_valid);
+		m_graphics_state.clear(rsx::rtt_config_contested | rsx::rtt_config_valid | rsx::rtt_config_no_attachments);
 		m_current_framebuffer_context = context;
 
 		if (layout.width == 0 || layout.height == 0)
@@ -1785,7 +1801,7 @@ namespace rsx
 			}
 
 			// Context must be draw now...
-			// TODO: Also disable rendering if ZPASS stat counting is not enabled (side-effect)
+			m_graphics_state.set(rsx::rtt_config_no_attachments);
 		}
 
 		// At least one attachment exists

rpcs3/Emu/RSX/RSXThread.h

@@ -365,6 +365,7 @@ namespace rsx
 		virtual void begin();
 		virtual void end();
 		virtual void execute_nop_draw();
+		bool should_skip_draw() const;
 
 		virtual void on_init_thread() = 0;
 		virtual void on_frame_end(u32 buffer, bool forced = false);

rpcs3/Emu/RSX/RSXZCULL.h

@@ -187,6 +187,15 @@ namespace rsx
 			// Check for pending writes
 			bool has_pending() const { return !m_pending_writes.empty(); }
 
+			// Check if queries are currently active
+			bool has_active_queries() const { return host_queries_active; }
+
+			// Check if ZPASS_COUNT stats are running
+			bool is_zpass_count_active() const { return zpass_count_enabled; }
+
+			// Grab the currently active query block
+			occlusion_query_info* get_current_query_task() const { return m_current_task; }
+
 			// Search for query synchronized at address
 			query_search_result find_query(vm::addr_t sink_address, bool all);