Reduce number of addressing modes in GDScript VM

There's now only 3 addressing modes: stack, constant, and member.

Self, class, and nil are now present respectively in the first 3 stack
slots. Global and class constants are moved to local constants when
compiling. Named globals is only present on editor to use on tool
singletons, so its use now emits a new instruction to copy the global to
the stack.

This allow us to further optimize the VM later by embedding the
addressing modes in the instructions themselves, which is better done
with less permutations.

1 files changed, 21 insertions, 23 deletions

diff --git a/modules/gdscript/gdscript_byte_codegen.cpp b/modules/gdscript/gdscript_byte_codegen.cpp
index ec1116197e..b553dcede3 100644
--- a/modules/gdscript/gdscript_byte_codegen.cpp
+++ b/modules/gdscript/gdscript_byte_codegen.cpp
@@ -59,12 +59,7 @@ uint32_t GDScriptByteCodeGenerator::add_local_constant(const StringName &p_name,
 }
 
 uint32_t GDScriptByteCodeGenerator::add_or_get_constant(const Variant &p_constant) {
-	if (constant_map.has(p_constant)) {
-		return constant_map[p_constant];
-	}
-	int index = constant_map.size();
-	constant_map[p_constant] = index;
-	return index;
+	return get_constant_pos(p_constant);
 }
 
 uint32_t GDScriptByteCodeGenerator::add_or_get_name(const StringName &p_name) {
@@ -612,7 +607,8 @@ void GDScriptByteCodeGenerator::write_assign(const Address &p_target, const Addr
 			} break;
 			case GDScriptDataType::NATIVE: {
 				int class_idx = GDScriptLanguage::get_singleton()->get_global_map()[p_target.type.native_type];
-				class_idx |= (GDScriptFunction::ADDR_TYPE_GLOBAL << GDScriptFunction::ADDR_BITS);
+				Variant nc = GDScriptLanguage::get_singleton()->get_global_array()[class_idx];
+				class_idx = get_constant_pos(nc) | (GDScriptFunction::ADDR_TYPE_CONSTANT << GDScriptFunction::ADDR_BITS);
 				append(GDScriptFunction::OPCODE_ASSIGN_TYPED_NATIVE, 3);
 				append(p_target);
 				append(p_source);
@@ -621,8 +617,7 @@ void GDScriptByteCodeGenerator::write_assign(const Address &p_target, const Addr
 			case GDScriptDataType::SCRIPT:
 			case GDScriptDataType::GDSCRIPT: {
 				Variant script = p_target.type.script_type;
-				int idx = get_constant_pos(script);
-				idx |= (GDScriptFunction::ADDR_TYPE_LOCAL_CONSTANT << GDScriptFunction::ADDR_BITS);
+				int idx = get_constant_pos(script) | (GDScriptFunction::ADDR_TYPE_CONSTANT << GDScriptFunction::ADDR_BITS);
 
 				append(GDScriptFunction::OPCODE_ASSIGN_TYPED_SCRIPT, 3);
 				append(p_target);
@@ -673,6 +668,12 @@ void GDScriptByteCodeGenerator::write_assign_default_parameter(const Address &p_
 	function->default_arguments.push_back(opcodes.size());
 }
 
+void GDScriptByteCodeGenerator::write_store_named_global(const Address &p_dst, const StringName &p_global) {
+	append(GDScriptFunction::OPCODE_STORE_NAMED_GLOBAL, 1);
+	append(p_dst);
+	append(p_global);
+}
+
 void GDScriptByteCodeGenerator::write_cast(const Address &p_target, const Address &p_source, const GDScriptDataType &p_type) {
 	int index = 0;
 
@@ -683,16 +684,14 @@ void GDScriptByteCodeGenerator::write_cast(const Address &p_target, const Addres
 		} break;
 		case GDScriptDataType::NATIVE: {
 			int class_idx = GDScriptLanguage::get_singleton()->get_global_map()[p_type.native_type];
-			class_idx |= (GDScriptFunction::ADDR_TYPE_GLOBAL << GDScriptFunction::ADDR_BITS);
+			Variant nc = GDScriptLanguage::get_singleton()->get_global_array()[class_idx];
 			append(GDScriptFunction::OPCODE_CAST_TO_NATIVE, 3);
-			index = class_idx;
+			index = get_constant_pos(nc) | (GDScriptFunction::ADDR_TYPE_CONSTANT << GDScriptFunction::ADDR_BITS);
 		} break;
 		case GDScriptDataType::SCRIPT:
 		case GDScriptDataType::GDSCRIPT: {
 			Variant script = p_type.script_type;
-			int idx = get_constant_pos(script);
-			idx |= (GDScriptFunction::ADDR_TYPE_LOCAL_CONSTANT << GDScriptFunction::ADDR_BITS);
-
+			int idx = get_constant_pos(script) | (GDScriptFunction::ADDR_TYPE_CONSTANT << GDScriptFunction::ADDR_BITS);
 			append(GDScriptFunction::OPCODE_CAST_TO_SCRIPT, 3);
 			index = idx;
 		} break;
@@ -903,7 +902,7 @@ void GDScriptByteCodeGenerator::write_call_self(const Address &p_target, const S
 	for (int i = 0; i < p_arguments.size(); i++) {
 		append(p_arguments[i]);
 	}
-	append(GDScriptFunction::ADDR_TYPE_SELF << GDScriptFunction::ADDR_BITS);
+	append(GDScriptFunction::ADDR_TYPE_STACK << GDScriptFunction::ADDR_BITS);
 	append(p_target);
 	append(p_arguments.size());
 	append(p_function_name);
@@ -914,7 +913,7 @@ void GDScriptByteCodeGenerator::write_call_self_async(const Address &p_target, c
 	for (int i = 0; i < p_arguments.size(); i++) {
 		append(p_arguments[i]);
 	}
-	append(GDScriptFunction::ADDR_TYPE_SELF << GDScriptFunction::ADDR_BITS);
+	append(GDScriptFunction::ADDR_SELF);
 	append(p_target);
 	append(p_arguments.size());
 	append(p_function_name);
@@ -999,7 +998,7 @@ void GDScriptByteCodeGenerator::write_construct_typed_array(const Address &p_tar
 	if (p_element_type.script_type) {
 		Variant script_type = Ref<Script>(p_element_type.script_type);
 		int addr = get_constant_pos(script_type);
-		addr |= GDScriptFunction::ADDR_TYPE_LOCAL_CONSTANT << GDScriptFunction::ADDR_BITS;
+		addr |= GDScriptFunction::ADDR_TYPE_CONSTANT << GDScriptFunction::ADDR_BITS;
 		append(addr);
 	} else {
 		append(Address()); // null.
@@ -1296,8 +1295,7 @@ void GDScriptByteCodeGenerator::write_return(const Address &p_return_value) {
 				const GDScriptDataType &element_type = function->return_type.get_container_element_type();
 
 				Variant script = function->return_type.script_type;
-				int script_idx = get_constant_pos(script);
-				script_idx |= (GDScriptFunction::ADDR_TYPE_LOCAL_CONSTANT << GDScriptFunction::ADDR_BITS);
+				int script_idx = get_constant_pos(script) | (GDScriptFunction::ADDR_TYPE_CONSTANT << GDScriptFunction::ADDR_BITS);
 
 				append(GDScriptFunction::OPCODE_RETURN_TYPED_ARRAY, 2);
 				append(p_return_value);
@@ -1326,7 +1324,7 @@ void GDScriptByteCodeGenerator::write_return(const Address &p_return_value) {
 
 					Variant script = function->return_type.script_type;
 					int script_idx = get_constant_pos(script);
-					script_idx |= (GDScriptFunction::ADDR_TYPE_LOCAL_CONSTANT << GDScriptFunction::ADDR_BITS);
+					script_idx |= (GDScriptFunction::ADDR_TYPE_CONSTANT << GDScriptFunction::ADDR_BITS);
 
 					append(GDScriptFunction::OPCODE_RETURN_TYPED_ARRAY, 2);
 					append(p_return_value);
@@ -1343,14 +1341,14 @@ void GDScriptByteCodeGenerator::write_return(const Address &p_return_value) {
 				append(GDScriptFunction::OPCODE_RETURN_TYPED_NATIVE, 2);
 				append(p_return_value);
 				int class_idx = GDScriptLanguage::get_singleton()->get_global_map()[function->return_type.native_type];
-				class_idx |= (GDScriptFunction::ADDR_TYPE_GLOBAL << GDScriptFunction::ADDR_BITS);
+				Variant nc = GDScriptLanguage::get_singleton()->get_global_array()[class_idx];
+				class_idx = get_constant_pos(nc) | (GDScriptFunction::ADDR_TYPE_CONSTANT << GDScriptFunction::ADDR_BITS);
 				append(class_idx);
 			} break;
 			case GDScriptDataType::GDSCRIPT:
 			case GDScriptDataType::SCRIPT: {
 				Variant script = function->return_type.script_type;
-				int script_idx = get_constant_pos(script);
-				script_idx |= (GDScriptFunction::ADDR_TYPE_LOCAL_CONSTANT << GDScriptFunction::ADDR_BITS);
+				int script_idx = get_constant_pos(script) | (GDScriptFunction::ADDR_TYPE_CONSTANT << GDScriptFunction::ADDR_BITS);
 
 				append(GDScriptFunction::OPCODE_RETURN_TYPED_SCRIPT, 2);
 				append(p_return_value);