From 73793ab89cb5805509e0eef3136058cc9181677c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bart=C5=82omiej=20T=2E=20Listwon?= <blistwon@gmail.com>
Date: Wed, 3 Jan 2024 12:03:56 +0100
Subject: [PATCH] Prevent shuffling custom shader functions (shader cache
 requires determinism)

---
 drivers/gles2/shader_compiler_gles2.cpp | 13 +++++++------
 drivers/gles3/shader_compiler_gles3.cpp | 13 +++++++------
 servers/visual/shader_language.cpp      |  2 +-
 servers/visual/shader_language.h        |  2 +-
 4 files changed, 16 insertions(+), 14 deletions(-)

diff --git a/drivers/gles2/shader_compiler_gles2.cpp b/drivers/gles2/shader_compiler_gles2.cpp
index a56fe87b768..9948a35765b 100644
--- a/drivers/gles2/shader_compiler_gles2.cpp
+++ b/drivers/gles2/shader_compiler_gles2.cpp
@@ -229,17 +229,18 @@ void ShaderCompilerGLES2::_dump_function_deps(const SL::ShaderNode *p_node, cons
 
 	ERR_FAIL_COND(fidx == -1);
 
-	for (Set<StringName>::Element *E = p_node->functions[fidx].uses_function.front(); E; E = E->next()) {
-		if (r_added.has(E->get())) {
+	for (int ufidx = 0; ufidx < p_node->functions[fidx].uses_function.size(); ufidx++) {
+		StringName function_name = p_node->functions[fidx].uses_function[ufidx];
+		if (r_added.has(function_name)) {
 			continue;
 		}
 
-		_dump_function_deps(p_node, E->get(), p_func_code, r_to_add, r_added);
+		_dump_function_deps(p_node, function_name, p_func_code, r_to_add, r_added);
 
 		SL::FunctionNode *fnode = nullptr;
 
 		for (int i = 0; i < p_node->functions.size(); i++) {
-			if (p_node->functions[i].name == E->get()) {
+			if (p_node->functions[i].name == function_name) {
 				fnode = p_node->functions[i].function;
 				break;
 			}
@@ -272,9 +273,9 @@ void ShaderCompilerGLES2::_dump_function_deps(const SL::ShaderNode *p_node, cons
 
 		header += ")\n";
 		r_to_add += header.as_string();
-		r_to_add += p_func_code[E->get()];
+		r_to_add += p_func_code[function_name];
 
-		r_added.insert(E->get());
+		r_added.insert(function_name);
 	}
 }
 
diff --git a/drivers/gles3/shader_compiler_gles3.cpp b/drivers/gles3/shader_compiler_gles3.cpp
index 443da3c62d3..746c2e91402 100644
--- a/drivers/gles3/shader_compiler_gles3.cpp
+++ b/drivers/gles3/shader_compiler_gles3.cpp
@@ -354,17 +354,18 @@ void ShaderCompilerGLES3::_dump_function_deps(const SL::ShaderNode *p_node, cons
 
 	ERR_FAIL_COND(fidx == -1);
 
-	for (Set<StringName>::Element *E = p_node->functions[fidx].uses_function.front(); E; E = E->next()) {
-		if (added.has(E->get())) {
+	for (int ufidx = 0; ufidx < p_node->functions[fidx].uses_function.size(); ufidx++) {
+		StringName function_name = p_node->functions[fidx].uses_function[ufidx];
+		if (added.has(function_name)) {
 			continue; //was added already
 		}
 
-		_dump_function_deps(p_node, E->get(), p_func_code, r_to_add, added);
+		_dump_function_deps(p_node, function_name, p_func_code, r_to_add, added);
 
 		SL::FunctionNode *fnode = nullptr;
 
 		for (int i = 0; i < p_node->functions.size(); i++) {
-			if (p_node->functions[i].name == E->get()) {
+			if (p_node->functions[i].name == function_name) {
 				fnode = p_node->functions[i].function;
 				break;
 			}
@@ -396,9 +397,9 @@ void ShaderCompilerGLES3::_dump_function_deps(const SL::ShaderNode *p_node, cons
 
 		header += ")\n";
 		r_to_add += header;
-		r_to_add += p_func_code[E->get()];
+		r_to_add += p_func_code[function_name];
 
-		added.insert(E->get());
+		added.insert(function_name);
 	}
 }
 
diff --git a/servers/visual/shader_language.cpp b/servers/visual/shader_language.cpp
index df03fdd94d0..cb7c11475d2 100644
--- a/servers/visual/shader_language.cpp
+++ b/servers/visual/shader_language.cpp
@@ -3405,7 +3405,7 @@ ShaderLanguage::Node *ShaderLanguage::_parse_expression(BlockNode *p_block, cons
 							//add to current function as dependency
 							for (int j = 0; j < shader->functions.size(); j++) {
 								if (shader->functions[j].name == current_function) {
-									shader->functions.write[j].uses_function.insert(name);
+									shader->functions.write[j].uses_function.push_back(name);
 									break;
 								}
 							}
diff --git a/servers/visual/shader_language.h b/servers/visual/shader_language.h
index 24b9a2f8aea..6472db6f41f 100644
--- a/servers/visual/shader_language.h
+++ b/servers/visual/shader_language.h
@@ -602,7 +602,7 @@ public:
 		struct Function {
 			StringName name;
 			FunctionNode *function;
-			Set<StringName> uses_function;
+			Vector<StringName> uses_function;
 			bool callable;
 		};