From 2d1943b8d1c6abcd19643a125b5e64e0a0d97fd4 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Pedro=20J=2E=20Est=C3=A9banez?= <pedrojrulez@gmail.com>
Date: Sun, 13 Jun 2021 13:32:44 +0200
Subject: [PATCH] Fix slow load/save of scenes with many instances of the same
 script

(cherry picked from commit 2ca6b9c61028b10bd1b7821cd32f6fbf505d71d1)
---
 modules/gdscript/gdscript.cpp  | 14 +++++++++-----
 modules/gdscript/gdscript.h    |  2 +-
 modules/mono/csharp_script.cpp | 14 +++++++++-----
 modules/mono/csharp_script.h   |  3 ++-
 4 files changed, 21 insertions(+), 12 deletions(-)

diff --git a/modules/gdscript/gdscript.cpp b/modules/gdscript/gdscript.cpp
index 48bbb6a857c..39799d76f47 100644
--- a/modules/gdscript/gdscript.cpp
+++ b/modules/gdscript/gdscript.cpp
@@ -310,7 +310,7 @@ PlaceHolderScriptInstance *GDScript::placeholder_instance_create(Object *p_this)
 #ifdef TOOLS_ENABLED
 	PlaceHolderScriptInstance *si = memnew(PlaceHolderScriptInstance(GDScriptLanguage::get_singleton(), Ref<Script>(this), p_this));
 	placeholders.insert(si);
-	_update_exports();
+	_update_exports(nullptr, false, si);
 	return si;
 #else
 	return NULL;
@@ -357,7 +357,7 @@ void GDScript::_update_exports_values(Map<StringName, Variant> &values, List<Pro
 }
 #endif
 
-bool GDScript::_update_exports(bool *r_err, bool p_recursive_call) {
+bool GDScript::_update_exports(bool *r_err, bool p_recursive_call, PlaceHolderScriptInstance *p_instance_to_update) {
 #ifdef TOOLS_ENABLED
 
 	static Vector<GDScript *> base_caches;
@@ -480,15 +480,19 @@ bool GDScript::_update_exports(bool *r_err, bool p_recursive_call) {
 		}
 	}
 
-	if (placeholders.size()) { //hm :(
+	if ((changed || p_instance_to_update) && placeholders.size()) { //hm :(
 
 		// update placeholders if any
 		Map<StringName, Variant> values;
 		List<PropertyInfo> propnames;
 		_update_exports_values(values, propnames);
 
-		for (Set<PlaceHolderScriptInstance *>::Element *E = placeholders.front(); E; E = E->next()) {
-			E->get()->update(propnames, values);
+		if (changed) {
+			for (Set<PlaceHolderScriptInstance *>::Element *E = placeholders.front(); E; E = E->next()) {
+				E->get()->update(propnames, values);
+			}
+		} else {
+			p_instance_to_update->update(propnames, values);
 		}
 	}
 
diff --git a/modules/gdscript/gdscript.h b/modules/gdscript/gdscript.h
index d90aea28891..8f0ac3889f6 100644
--- a/modules/gdscript/gdscript.h
+++ b/modules/gdscript/gdscript.h
@@ -129,7 +129,7 @@ class GDScript : public Script {
 
 #endif
 
-	bool _update_exports(bool *r_err = nullptr, bool p_recursive_call = false);
+	bool _update_exports(bool *r_err = nullptr, bool p_recursive_call = false, PlaceHolderScriptInstance *p_instance_to_update = nullptr);
 
 	void _save_orphaned_subclasses();
 
diff --git a/modules/mono/csharp_script.cpp b/modules/mono/csharp_script.cpp
index d8652d5cf7a..10cb6baaf11 100644
--- a/modules/mono/csharp_script.cpp
+++ b/modules/mono/csharp_script.cpp
@@ -2214,7 +2214,7 @@ void CSharpScript::_update_member_info_no_exports() {
 }
 #endif
 
-bool CSharpScript::_update_exports() {
+bool CSharpScript::_update_exports(PlaceHolderScriptInstance *p_instance_to_update) {
 #ifdef TOOLS_ENABLED
 	bool is_editor = Engine::get_singleton()->is_editor_hint();
 	if (is_editor)
@@ -2385,14 +2385,18 @@ bool CSharpScript::_update_exports() {
 	if (is_editor) {
 		placeholder_fallback_enabled = false;
 
-		if (placeholders.size()) {
+		if ((changed || p_instance_to_update) && placeholders.size()) {
 			// Update placeholders if any
 			Map<StringName, Variant> values;
 			List<PropertyInfo> propnames;
 			_update_exports_values(values, propnames);
 
-			for (Set<PlaceHolderScriptInstance *>::Element *E = placeholders.front(); E; E = E->next()) {
-				E->get()->update(propnames, values);
+			if (changed) {
+				for (Set<PlaceHolderScriptInstance *>::Element *E = placeholders.front(); E; E = E->next()) {
+					E->get()->update(propnames, values);
+				}
+			} else {
+				p_instance_to_update->update(propnames, values);
 			}
 		}
 	}
@@ -2989,7 +2993,7 @@ PlaceHolderScriptInstance *CSharpScript::placeholder_instance_create(Object *p_t
 #ifdef TOOLS_ENABLED
 	PlaceHolderScriptInstance *si = memnew(PlaceHolderScriptInstance(CSharpLanguage::get_singleton(), Ref<Script>(this), p_this));
 	placeholders.insert(si);
-	_update_exports();
+	_update_exports(si);
 	return si;
 #else
 	return NULL;
diff --git a/modules/mono/csharp_script.h b/modules/mono/csharp_script.h
index 6dce21d7c49..5a737226832 100644
--- a/modules/mono/csharp_script.h
+++ b/modules/mono/csharp_script.h
@@ -135,7 +135,8 @@ class CSharpScript : public Script {
 	void load_script_signals(GDMonoClass *p_class, GDMonoClass *p_native_class);
 	bool _get_signal(GDMonoClass *p_class, GDMonoClass *p_delegate, Vector<Argument> &params);
 
-	bool _update_exports();
+	bool _update_exports(PlaceHolderScriptInstance *p_instance_to_update = nullptr);
+
 	bool _get_member_export(IMonoClassMember *p_member, bool p_inspect_export, PropertyInfo &r_prop_info, bool &r_exported);
 #ifdef TOOLS_ENABLED
 	static int _try_get_member_export_hint(IMonoClassMember *p_member, ManagedType p_type, Variant::Type p_variant_type, bool p_allow_generics, PropertyHint &r_hint, String &r_hint_string);