Add GDScript code generation interface

Implement the abstraction by targeting the current VM.

1 files changed, 160 insertions, 0 deletions

diff --git a/modules/gdscript/gdscript_codegen.h b/modules/gdscript/gdscript_codegen.h
new file mode 100644
index 0000000000..31e1e6ba23
--- /dev/null
+++ b/modules/gdscript/gdscript_codegen.h
@@ -0,0 +1,160 @@
+/*************************************************************************/
+/*  gdscript_codegen.h                                                   */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2020 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2020 Godot Engine contributors (cf. AUTHORS.md).   */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+
+#ifndef GDSCRIPT_CODEGEN
+#define GDSCRIPT_CODEGEN
+
+#include "core/io/multiplayer_api.h"
+#include "core/string_name.h"
+#include "core/variant.h"
+#include "gdscript_function.h"
+#include "gdscript_functions.h"
+
+class GDScriptCodeGenerator {
+public:
+	struct Address {
+		enum AddressMode {
+			SELF,
+			CLASS,
+			MEMBER,
+			CONSTANT,
+			CLASS_CONSTANT,
+			LOCAL_CONSTANT,
+			LOCAL_VARIABLE,
+			FUNCTION_PARAMETER,
+			TEMPORARY,
+			GLOBAL,
+			NAMED_GLOBAL,
+			NIL,
+		};
+		AddressMode mode = NIL;
+		uint32_t address = 0;
+		GDScriptDataType type;
+
+		Address() {}
+		Address(AddressMode p_mode, const GDScriptDataType &p_type = GDScriptDataType()) {
+			mode = p_mode;
+			type = p_type;
+		}
+		Address(AddressMode p_mode, uint32_t p_address, const GDScriptDataType &p_type = GDScriptDataType()) {
+			mode = p_mode,
+			address = p_address;
+			type = p_type;
+		}
+	};
+
+	virtual uint32_t add_parameter(const StringName &p_name, bool p_is_optional, const GDScriptDataType &p_type) = 0;
+	virtual uint32_t add_local(const StringName &p_name, const GDScriptDataType &p_type) = 0;
+	virtual uint32_t add_local_constant(const StringName &p_name, const Variant &p_constant) = 0;
+	virtual uint32_t add_or_get_constant(const Variant &p_constant) = 0;
+	virtual uint32_t add_or_get_name(const StringName &p_name) = 0;
+	virtual uint32_t add_temporary() = 0;
+	virtual void pop_temporary() = 0;
+
+	virtual void start_parameters() = 0;
+	virtual void end_parameters() = 0;
+
+	virtual void start_block() = 0;
+	virtual void end_block() = 0;
+
+	// virtual int get_max_stack_level() = 0;
+	// virtual int get_max_function_arguments() = 0;
+
+	virtual void write_start(GDScript *p_script, const StringName &p_function_name, bool p_static, MultiplayerAPI::RPCMode p_rpc_mode, const GDScriptDataType &p_return_type) = 0;
+	virtual GDScriptFunction *write_end() = 0;
+
+#ifdef DEBUG_ENABLED
+	virtual void set_signature(const String &p_signature) = 0;
+#endif
+	virtual void set_initial_line(int p_line) = 0;
+
+	// virtual void alloc_stack(int p_level) = 0; // Is this needed?
+	// virtual void alloc_call(int p_arg_count) = 0; // This might be automatic from other functions.
+
+	virtual void write_operator(const Address &p_target, Variant::Operator p_operator, const Address &p_left_operand, const Address &p_right_operand) = 0;
+	virtual void write_type_test(const Address &p_target, const Address &p_source, const Address &p_type) = 0;
+	virtual void write_type_test_builtin(const Address &p_target, const Address &p_source, Variant::Type p_type) = 0;
+	virtual void write_and_left_operand(const Address &p_left_operand) = 0;
+	virtual void write_and_right_operand(const Address &p_right_operand) = 0;
+	virtual void write_end_and(const Address &p_target) = 0;
+	virtual void write_or_left_operand(const Address &p_left_operand) = 0;
+	virtual void write_or_right_operand(const Address &p_right_operand) = 0;
+	virtual void write_end_or(const Address &p_target) = 0;
+	virtual void write_start_ternary(const Address &p_target) = 0;
+	virtual void write_ternary_condition(const Address &p_condition) = 0;
+	virtual void write_ternary_true_expr(const Address &p_expr) = 0;
+	virtual void write_ternary_false_expr(const Address &p_expr) = 0;
+	virtual void write_end_ternary() = 0;
+	virtual void write_set(const Address &p_target, const Address &p_index, const Address &p_source) = 0;
+	virtual void write_get(const Address &p_target, const Address &p_index, const Address &p_source) = 0;
+	virtual void write_set_named(const Address &p_target, const StringName &p_name, const Address &p_source) = 0;
+	virtual void write_get_named(const Address &p_target, const StringName &p_name, const Address &p_source) = 0;
+	virtual void write_set_member(const Address &p_value, const StringName &p_name) = 0;
+	virtual void write_get_member(const Address &p_target, const StringName &p_name) = 0;
+	virtual void write_assign(const Address &p_target, const Address &p_source) = 0;
+	virtual void write_assign_true(const Address &p_target) = 0;
+	virtual void write_assign_false(const Address &p_target) = 0;
+	virtual void write_cast(const Address &p_target, const Address &p_source, const GDScriptDataType &p_type) = 0;
+	virtual void write_call(const Address &p_target, const Address &p_base, const StringName &p_function_name, const Vector<Address> &p_arguments) = 0;
+	virtual void write_super_call(const Address &p_target, const StringName &p_function_name, const Vector<Address> &p_arguments) = 0;
+	virtual void write_call_async(const Address &p_target, const Address &p_base, const StringName &p_function_name, const Vector<Address> &p_arguments) = 0;
+	virtual void write_call_builtin(const Address &p_target, GDScriptFunctions::Function p_function, const Vector<Address> &p_arguments) = 0;
+	virtual void write_call_method_bind(const Address &p_target, const Address &p_base, const MethodBind *p_method, const Vector<Address> &p_arguments) = 0;
+	virtual void write_call_ptrcall(const Address &p_target, const Address &p_base, const MethodBind *p_method, const Vector<Address> &p_arguments) = 0;
+	virtual void write_call_self(const Address &p_target, const StringName &p_function_name, const Vector<Address> &p_arguments) = 0;
+	virtual void write_call_script_function(const Address &p_target, const Address &p_base, const StringName &p_function_name, const Vector<Address> &p_arguments) = 0;
+	virtual void write_construct(const Address &p_target, Variant::Type p_type, const Vector<Address> &p_arguments) = 0;
+	virtual void write_construct_array(const Address &p_target, const Vector<Address> &p_arguments) = 0;
+	virtual void write_construct_dictionary(const Address &p_target, const Vector<Address> &p_arguments) = 0;
+	virtual void write_await(const Address &p_target, const Address &p_operand) = 0;
+	virtual void write_if(const Address &p_condition) = 0;
+	// virtual void write_elseif(const Address &p_condition) = 0; This kind of makes things more difficult for no real benefit.
+	virtual void write_else() = 0;
+	virtual void write_endif() = 0;
+	virtual void write_for(const Address &p_variable, const Address &p_list) = 0;
+	virtual void write_endfor() = 0;
+	virtual void start_while_condition() = 0; // Used to allow a jump to the expression evaluation.
+	virtual void write_while(const Address &p_condition) = 0;
+	virtual void write_endwhile() = 0;
+	virtual void start_match() = 0;
+	virtual void start_match_branch() = 0;
+	virtual void end_match() = 0;
+	virtual void write_break() = 0;
+	virtual void write_continue() = 0;
+	virtual void write_continue_match() = 0;
+	virtual void write_breakpoint() = 0;
+	virtual void write_newline(int p_line) = 0;
+	virtual void write_return(const Address &p_return_value) = 0;
+	virtual void write_assert(const Address &p_test, const Address &p_message) = 0;
+
+	virtual ~GDScriptCodeGenerator() {}
+};
+
+#endif // GDSCRIPT_CODEGEN