rsx: Add duplicate section detection when there are too many sections in the surface cache

- Check for useless sections.
  Helps in games that create a bunch of sections randomly for one-time use

rpcs3/Emu/RSX/Common/surface_store.h

@@ -956,6 +956,49 @@ namespace rsx
 			return result;
 		}
 
+		void check_for_duplicates(std::vector<surface_overlap_info>& sections, const rsx::address_range& range)
+		{
+			// Generic painter's algorithm to detect obsolete sections
+			ensure(range.length() < 64 * 0x100000);
+			std::vector<u8> marker(range.length());
+			std::memset(marker.data(), 0, range.length());
+
+			for (auto it = sections.crbegin(); it != sections.crend(); ++it)
+			{
+				if (it->base_address < range.start)
+				{
+					continue;
+				}
+
+				const auto true_pitch_in_bytes = it->surface->get_surface_width(rsx::surface_metrics::bytes);
+				const auto true_height_in_rows = it->surface->get_surface_height(rsx::surface_metrics::samples);
+
+				bool valid = false;
+				auto addr = it->base_address - range.start;
+				auto data = marker.data();
+
+				for (usz row = 0; row < true_height_in_rows; ++row)
+				{
+					for (usz col = 0; col < true_pitch_in_bytes; ++col)
+					{
+						if (const auto loc = col + addr; !data[loc])
+						{
+							valid = true;
+							data[loc] = 1;
+						}
+					}
+
+					addr += true_pitch_in_bytes;
+				}
+
+				if (!valid)
+				{
+					rsx_log.error("Stale surface at address 0x%x will be deleted", it->base_address);
+					invalidate_surface_address(it->base_address, it->is_depth);
+				}
+			}
+		}
+
 		void on_write(const bool* color, bool z)
 		{
 			if (write_tag == cache_tag && m_skip_write_updates)

rpcs3/Emu/RSX/Common/texture_cache.h

@@ -1783,6 +1783,26 @@ namespace rsx
 
 						if (result_is_valid)
 						{
+							// Check for possible duplicates
+							usz max_safe_sections = UINT32_MAX;
+							switch (result.external_subresource_desc.op)
+							{
+							case deferred_request_command::atlas_gather:
+								max_safe_sections = 8 + attr.mipmaps; break;
+							case deferred_request_command::cubemap_gather:
+								max_safe_sections = 8 * attr.mipmaps; break;
+							case deferred_request_command::_3d_gather:
+								max_safe_sections = (attr.depth * attr.mipmaps * 110) / 100; break; // 10% factor of safety
+							default:
+								break;
+							}
+
+							if (overlapping_fbos.size() > max_safe_sections)
+							{
+								rsx_log.error("[Performance warning] Texture gather routine encountered too many objects!");
+								m_rtts.check_for_duplicates(overlapping_fbos, memory_range);
+							}
+
 							// Optionally disallow caching if resource is being written to as it is being read from
 							for (const auto& section : overlapping_fbos)
 							{
@@ -1855,6 +1875,7 @@ namespace rsx
 			attributes.bpp = get_format_block_size_in_bytes(attributes.gcm_format);
 			attributes.width = tex.width();
 			attributes.height = tex.height();
+			attributes.mipmaps = tex.get_exact_mipmap_count();
 			attributes.swizzled = !(tex.format() & CELL_GCM_TEXTURE_LN);
 
 			const bool is_unnormalized = !!(tex.format() & CELL_GCM_TEXTURE_UN);