elna/boot/stage18/cl.elna

(*
 * This Source Code Form is subject to the terms of the Mozilla Public License,
 * v. 2.0. If a copy of the MPL was not distributed with this file, You can
 * obtain one at https://mozilla.org/MPL/2.0/.
 *)
program;

(* Stage 18 compiler. *)

(* - Record fields can be aggregates themselves *)

type
	(**
	 * List of intermediate representation items.
	 *)
	ElnaInstructionList = record
		next: Word
	end;
	ElnaInstructionModule = record
		data: Word;
		code: Word
	end;
	ElnaInstructionDeclaration = record
		next: Word;
		name: Word;
		length: Word;
		body: Word;
		stack: Word;
		parameters: Word;
		count: Word
	end;

	(* Type representation. *)
	ElnaTypeKind = (primitive, enumeration, _record, pointer, array);
	ElnaType = record
		kind: ElnaTypeKind;
		size: Word
	end;
	ElnaTypeEnumeration = record
		kind: ElnaTypeKind;
		size: Word;
		members: Word;
		length: Word
	end;
	ElnaTypeField = record
		name: ElnaTypeKind;
		length: Word;
		field_type: ^ElnaType
	end;
	ElnaTypeRecord = record
		kind: ElnaTypeKind;
		size: Word;
		members: Word;
		length: Word
	end;
	ElnaTypePointer = record
		kind: ElnaTypeKind;
		size: Word;
		base: Word
	end;
	ElnaTypeArray = record
		kind: ElnaTypeKind;
		size: Word;
		base: Word;
		length: Word
	end;

	(* Abstract syntax tree nodes. *)
	ElnaTreeKind = (
		integer_literal,
		string_literal,
		character_literal,
		boolean_literal,
		variable_expression,
		field_access_expression,
		dereference_expression,
		unary_expression,
		binary_expression,
		call,
		goto_statement,
		label_declaration,
		return_statement,
		assign_statement,
		if_statement,
		procedure_declaration,
		variable_declaration,
		enumeration_type_expression,
		named_type_expression,
		type_declaration,
		module_declaration,
		record_type_expression,
		pointer_type_expression,
		array_type_expression,
		null,
		trait_expression
	);
	ElnaTreeNode = record
		kind: ElnaTreeKind
	end;
	ElnaTreeExpression = record
		kind: ElnaTreeKind;
		type_decoration: ^ElnaType
	end;
	ElnaTreeIntegerLiteral = record
		kind: ElnaTreeKind;
		type_decoration: ^ElnaType;
		value: Word
	end;
	ElnaTreeCharacterLiteral = record
		kind: ElnaTreeKind;
		type_decoration: ^ElnaType;
		value: Word;
		length: Word
	end;
	ElnaTreeNilLiteral = record
		kind: ElnaTreeKind;
		type_decoration: ^ElnaType
	end;
	ElnaTreeBooleanLiteral = record
		kind: ElnaTreeKind;
		type_decoration: ^ElnaType;
		value: Word
	end;
	ElnaTreeVariableExpression = record
		kind: ElnaTreeKind;
		type_decoration: ^ElnaType;
		name: Word;
		length: Word
	end;
	ElnaTreeStringLiteral = record
		kind: ElnaTreeKind;
		type_decoration: ^ElnaType;
		value: Word;
		length: Word
	end;
	ElnaTreeDereferenceExpression = record
		kind: ElnaTreeKind;
		type_decoration: ^ElnaType;
		pointer: Word
	end;
	ElnaTreeBinaryExpression = record
		kind: ElnaTreeKind;
		type_decoration: ^ElnaType;
		lhs: Word;
		rhs: Word;
		operator: Word
	end;
	ElnaTreeUnaryExpression = record
		kind: ElnaTreeKind;
		type_decoration: ^ElnaType;
		operand: Word;
		operator: Word
	end;

	(**
	 * All statements are chained into a list. Next contains a pointer to the next
	 * statement in the statement list.
	 *)
	ElnaTreeStatement = record
		kind: ElnaTreeKind;
		next: Word
	end;
	ElnaTreeIfStatement = record
		kind: ElnaTreeKind;
		next: Word;
		conditionals: Word;
		_else: ^ElnaTreeStatement
	end;
	ElnaTreeGotoStatement = record
		kind: ElnaTreeKind;
		next: Word;
		label: Word;
		length: Word
	end;
	ElnaTreeAssignStatement = record
		kind: ElnaTreeKind;
		next: Word;
		assignee: Word;
		assignment: ^ElnaTreeExpression
	end;
	ElnaTreeReturnStatement = record
		kind: ElnaTreeKind;
		next: Word;
		returned: ^ElnaTreeExpression
	end;
	ElnaTreeLabelDeclaration = record
		kind: ElnaTreeKind;
		next: Word;
		label: Word;
		length: Word
	end;
	ElnaTreeFieldAccessExpression = record
		kind: ElnaTreeKind;
		type_decoration: ^ElnaType;
		aggregate: Word;
		field: Word;
		length: Word
	end;
	ElnaTreeEnumerationTypeExpression = record
		kind: ElnaTreeKind;
		members: Word;
		length: Word
	end;
	ElnaTreeRecordTypeExpression = record
		kind: ElnaTreeKind;
		members: Word;
		length: Word
	end;
	ElnaTreeNamedTypeExpression = record
		kind: ElnaTreeKind;
		name: Word;
		length: Word
	end;
	ElnaTreePointerTypeExpression = record
		kind: ElnaTreeKind;
		base: ^ElnaTreeNode
	end;
	ElnaTreeArrayTypeExpression = record
		kind: ElnaTreeKind;
		base: ^ElnaTreeNode;
		length: Word
	end;
	ElnaTreeTraitExpression = record
		kind: ElnaTreeKind;
		name: Word;
		length: Word;
		argument: Word
	end;
	(**
	 * Conditional statements is a list of pairs: condition and statements.
	 * Used for example to represent if and elsif blocks with beloning statements.
	 *)
	ElnaTreeConditionalStatements = record
		condition: ^ElnaTreeExpression;
		statements: ^ElnaTreeStatement;
		next: Word
	end;
	ElnaTreeDeclaration = record
		kind: ElnaTreeKind;
		next: Word;
		name: Word;
		length: Word
	end;
	ElnaTreeModuleDeclaration = record
		kind: ElnaTreeKind;
		types: Word;
		globals: Word;
		procedures: Word
	end;
	ElnaTreeProcedureDeclaration = record
		kind: ElnaTreeKind;
		next: Word;
		name: Word;
		length: Word;
		body: Word;
		temporaries: Word;
		parameters: Word
	end;
	ElnaTreeTypeDeclaration = record
		kind: ElnaTreeKind;
		next: Word;
		name: Word;
		length: Word;
		_type: Word
	end;
	ElnaTreeVariableDeclaration = record
		kind: ElnaTreeKind;
		next: Word;
		name: Word;
		length: Word;
		_type: Word
	end;

	(* Symbol table information. *)
	ElnaSymbolInfoKind = (type_info, parameter_info, temporary_info, procedure_info);
	ElnaSymbolInfo = record
		kind: ElnaSymbolInfoKind
	end;
	ElnaSymbolTypeInfo = record
		kind: ElnaSymbolInfoKind;
		_type: ^ElnaType
	end;
	ElnaSymbolTemporaryInfo = record
		kind: ElnaSymbolInfoKind;
		offset: Word;
		variable_type: Word
	end;
	ElnaSymbolProcedureInfo = record
		kind: ElnaSymbolInfoKind;
		symbol_table: Word
	end;

	ElnaErrorList = record
		first: Word;
		last: Word
	end;
	ElnaError = record
		next: Word
	end;

	ElnaLexerAction = (none, accumulate, skip, single, eof, finalize, composite, key_id, integer, delimited);

	(**
	 * Classification table assigns each possible character to a group (class). All
	 * characters of the same group a handled equivalently.
	 *
	 * Transition = record
	 *   action: TransitionAction;
	 *   next_state: TransitionState
	 * end;
	 *)
	ElnaLexerClass = (
		invalid,
		digit,
		alpha,
		space,
		colon,
		equals,
		left_paren,
		right_paren,
		asterisk,
		backslash,
		single,
		hex,
		zero,
		x,
		eof,
		dot,
		minus,
		single_quote,
		double_quote,
		greater,
		less,
		other,
		number_sign
	);
	ElnaLexerState = (
		start,
		colon,
		identifier,
		decimal,
		leading_zero,
		greater,
		minus,
		left_paren,
		less,
		dot,
		comment,
		closing_comment,
		character,
		character_escape,
		string,
		string_escape,
		number_sign,
		trait,
		finish
	);
	ElnaLexerKind = (
		identifier,
		_const,
		_var,
		_proc,
		_type,
		_begin,
		_end,
		_if,
		_then,
		_else,
		_elsif,
		_while,
		_do,
		_extern,
		_record,
		boolean,
		null,
		and,
		_or,
		_xor,
		pipe,
		not,
		_return,
		_module,
		_program,
		_import,
		_cast,
		_defer,
		_case,
		_of,
		trait,
		left_paren,
		right_paren,
		left_square,
		right_square,
		shift_left,
		shift_right,
		greater_equal,
		less_equal,
		greater_than,
		less_than,
		not_equal,
		equals,
		semicolon,
		dot,
		comma,
		plus,
		arrow,
		minus,
		multiplication,
		division,
		remainder,
		assignment,
		colon,
		hat,
		at,
		comment,
		string,
		character,
		integer,
		word,
		_goto,
		eof
	);

	ElnaTacOperator = (
		get_address,
		add,
		load,
		store,
		proc_call,
		copy,
		subtract,
		divide,
		remainder,
		multiply,
		_xor,
		_or,
		and,
		less_than,
		greater_than,
		less_or_equal,
		greater_or_equal,
		equal,
		not_equal,
		negate,
		complement,
		jump,
		jump_if_zero,
		jump_if_not_zero,
		label,
		_return
	);
	ElnaRtlOperator = (
		li,
		la,
		add,
		addi,
		lw,
		sw,
		jal,
		move,
		sub,
		div,
		rem,
		mul,
		_xor,
		_or,
		and,
		seqz,
		snez,
		slt,
		xori,
		neg,
		not,
		j,
		beqz,
		bnez,
		label,
		allocate_stack,
		ret
	);
	ElnaTacOperand = (list, immediate, symbol, pseudo);
	ElnaRtlOperand = (register, immediate, symbol, pseudo, offset);
	ElnaRtlRegister = (
		zero,
		ra,
		sp,
		gp,
		tp,
		t0,
		t1,
		t2,
		s0,
		s1,
		a0,
		a1,
		a2,
		a3,
		a4,
		a5,
		a6,
		a7,
		s2,
		s3,
		s4,
		s5,
		s6,
		s7,
		s8,
		s9,
		s10,
		s11,
		t3,
		t4,
		t5,
		t6
	);

var
	symbol_table_global: Array;
	compiler_strings: Array;
	classification: Array;
	variable_map: Array;

	source_code: Word;
	compiler_strings_position: Word;
	compiler_strings_length: Word;
	label_counter: Word;
	symbol_table_store: Word;
	temporary_variable_counter: Word;

(**
 * Calculates and returns the string token length between quotes, including the
 * escaping slash characters.
 *
 * Parameters:
 * string - String token pointer.
 *
 * Returns the length in a0.
 *)
proc _string_length(string: Word);
var
	counter1: Word;
	current_byte1: Word;
begin
	(* Reset the counter. *)
	counter1 := 0;

	.string_length_loop;
	string := string + 1;

	current_byte1 := _load_byte(string);
	if current_byte1 <> '"' then
		counter1 := counter1 + 1;
		goto string_length_loop
	end;

	return counter1
end;

(**
 * Adds a string to the global, read-only string storage.
 *
 * Parameters:
 * string - String token.
 *
 * Returns the offset from the beginning of the storage to the new string in a0.
 *)
proc _add_string(string: Word);
var
	contents1: Word;
	result1: Word;
	current_byte1: Word;
begin
	contents1 := string + 1;
	result1 := compiler_strings_length;

	.add_string_loop;
	current_byte1 := _load_byte(contents1);
	if current_byte1 <> '"' then
		_store_byte(current_byte1, compiler_strings_position);
		compiler_strings_position := compiler_strings_position + 1;
		contents1 := contents1 + 1;

		if current_byte1 <> '\\' then
			compiler_strings_length := compiler_strings_length + 1
		end;
		goto add_string_loop
	end;

	return result1
end;

(**
 * Writes to the standard output.
 *
 * Parameters:
 * buffer - Buffer.
 * size - Buffer length.
 *)
proc _write_s(buffer: Word, size: Word);
begin
	write(1, buffer, size)
end;

(**
 * Writes a number to the standard output.
 *
 * Parameters:
 * number - Whole number.
 *)
proc _write_i(number: Word);
begin
	printf("%i\0", number);
	fflush(nil)
end;

(**
 * Writes a character from a0 into the standard output.
 *
 * Parameters:
 * character - Character to write.
 *)
proc _write_c(character: Word);
begin
	write(1, @character, 1)
end;

(**
 * Write null terminated string.
 *
 * Parameters:
 * string - String.
 *)
proc _write_z(string: Word);
begin
	printf("%s\0", string);
	fflush(nil)
end;

(**
 * Detects if the passed character is a 7-bit alpha character or an underscore.
 *
 * Paramters:
 * character - Tested character.
 *
 * Sets a0 to 1 if the character is an alpha character or underscore, sets it to 0 otherwise.
 *)
proc _is_alpha(character: Word);
var
	is_underscore1: Word;
begin
	is_underscore1 := character = '_';

	return isalpha(character) or is_underscore1
end;

proc _is_alnum(character: Word);
	return _is_alpha(character) or isdigit(character)
end;

proc _elna_tac_instruction_size();
	return 44
end;

proc _elna_tac_instruction_get_kind(this: Word);
begin
	this := this + 4;
	return this^
end;

proc _elna_tac_instruction_set_kind(this: Word, value: Word);
begin
	this := this + 4;
	this^ := value
end;

proc elna_instruction_list_concatenate(this: Word, value: Word);
var
	start1: Word;
begin
	if this = 0 then
		start1 := value;
		goto elna_instruction_list_concatenate_end
	else
		start1 := this
	end;
	.elna_instruction_list_concatenate_loop;
	if value <> 0 then
		if this^ <> 0 then
			this := this^;
			goto elna_instruction_list_concatenate_loop
		end
	end;
	this^ := value;
	.elna_instruction_list_concatenate_end;
	return start1
end;

proc _elna_tac_instruction_get_operand_type(this: Word, n: Word);
begin
	n := n - 1;
	n := n * 12;
	this := this + 8;
	this := this + n;

	return this^
end;

proc _elna_tac_instruction_get_operand_value(this: Word, n: Word);
begin
	n := n - 1;
	n := n * 12;
	this := this + 8;
	this := this + n;

	this := this + 4;
	return this^
end;

proc _elna_tac_instruction_get_operand_length(this: Word, n: Word);
begin
	n := n - 1;
	n := n * 12;
	this := this + 8;
	this := this + n;

	this := this + 8;
	return this^
end;

proc _elna_tac_instruction_set_operand(this: Word, n: Word, operand_type: Word, operand_value: Word, operand_length: Word);
begin
	n := n - 1;
	n := n * 12;
	this := this + 8;
	this := this + n;

	this^ := operand_type;
	this := this + 4;
	this^ := operand_value;
	this := this + 4;
	this^ := operand_length
end;

proc _elna_tac_instruction_create(kind: Word);
var
	result1: Word;
begin
	result1 := malloc(_elna_tac_instruction_size());

	_elna_tac_instruction_set_kind(result1, kind);
	elna_instruction_list_concatenate(result1, 0);

	return result1
end;

proc elna_rtl_instruction_create(kind: Word);
var
	result1: ^ElnaInstructionList;
begin
	result1 := malloc(elna_rtl_instruction_size());

	elna_rtl_instruction_set_kind(result1, kind);
	result1^.next := nil;

	return result1
end;

proc elna_rtl_instruction_size();
	return 44
end;

proc elna_rtl_instruction_get_kind(this: Word);
begin
	this := this + 4;
	return this^
end;

proc elna_rtl_instruction_set_kind(this: Word, value: Word);
begin
	this := this + 4;
	this^ := value
end;

proc elna_rtl_instruction_get_operand_type(this: Word, n: Word);
begin
	n := n - 1;
	n := n * 12;
	this := this + 8;
	this := this + n;

	return this^
end;

proc elna_rtl_instruction_get_operand_value(this: Word, n: Word);
begin
	n := n - 1;
	n := n * 12;
	this := this + 8;
	this := this + n;

	this := this + 4;
	return this^
end;

proc elna_rtl_instruction_get_operand_length(this: Word, n: Word);
begin
	n := n - 1;
	n := n * 12;
	this := this + 8;
	this := this + n;

	this := this + 8;
	return this^
end;

proc elna_rtl_instruction_set_operand(this: Word, n: Word, operand_type: Word, operand_value: Word, operand_length: Word);
begin
	n := n - 1;
	n := n * 12;
	this := this + 8;
	this := this + n;

	this^ := operand_type;
	this := this + 4;
	this^ := operand_value;
	this := this + 4;
	this^ := operand_length
end;

proc elna_rtl_load_operand_value(tac_instruction: Word, operand_number: Word, into: Word);
var
	result: ^ElnaInstructionList;
	operand_value: Word;
	operand_length: Word;
	operand_type: Word;
	next_instruction: Word;
begin
	operand_value := _elna_tac_instruction_get_operand_value(tac_instruction, operand_number);
	operand_length := _elna_tac_instruction_get_operand_length(tac_instruction, operand_number);
	operand_type := _elna_tac_instruction_get_operand_type(tac_instruction, operand_number);

	if operand_type = ElnaTacOperand.immediate then
		result := elna_rtl_instruction_create(ElnaRtlOperator.li);
		elna_rtl_instruction_set_operand(result, 1, ElnaRtlOperand.register, into, 0);
		elna_rtl_instruction_set_operand(result, 2, ElnaRtlOperand.immediate, operand_value, operand_length)
	elsif operand_type = ElnaTacOperand.symbol then
		result := elna_rtl_instruction_create(ElnaRtlOperator.la);
		elna_rtl_instruction_set_operand(result, 1, ElnaRtlOperand.register, into, 0);
		elna_rtl_instruction_set_operand(result, 2, ElnaRtlOperand.symbol, operand_value, operand_length);

		next_instruction := elna_rtl_instruction_create(ElnaRtlOperator.lw);
		elna_rtl_instruction_set_operand(next_instruction, 1, ElnaRtlOperand.register, into, 0);
		elna_rtl_instruction_set_operand(next_instruction, 2, ElnaRtlOperand.offset, into, 0);

		result^.next := next_instruction
	elsif operand_type = ElnaTacOperand.pseudo then
		result := elna_rtl_instruction_create(ElnaRtlOperator.move);
		elna_rtl_instruction_set_operand(result, 1, ElnaRtlOperand.register, into, 0);
		elna_rtl_instruction_set_operand(result, 2, ElnaRtlOperand.pseudo, operand_value, operand_length)
	end;

	return result
end;

proc elna_rtl_load_operand_address(tac_instruction: Word, operand_number: Word, into: Word);
var
	result: Word;
	operand_value: Word;
	operand_length: Word;
	operand_type: Word;
begin
	operand_value := _elna_tac_instruction_get_operand_value(tac_instruction, operand_number);
	operand_length := _elna_tac_instruction_get_operand_length(tac_instruction, operand_number);
	operand_type := _elna_tac_instruction_get_operand_type(tac_instruction, operand_number);

	if operand_type = ElnaTacOperand.symbol then
		result := elna_rtl_instruction_create(ElnaRtlOperator.la);
		elna_rtl_instruction_set_operand(result, 1, ElnaRtlOperand.register, into, 0);
		elna_rtl_instruction_set_operand(result, 2, ElnaRtlOperand.symbol, operand_value, operand_length)
	elsif operand_type = ElnaTacOperand.pseudo then
		result := elna_rtl_instruction_create(ElnaRtlOperator.la);
		elna_rtl_instruction_set_operand(result, 1, ElnaRtlOperand.register, into, 0);
		elna_rtl_instruction_set_operand(result, 2, ElnaRtlOperand.pseudo, operand_value, operand_length)
	end;

	return result
end;

proc elna_rtl_binary_operands(tac_instruction: Word, next_instruction: Word);
var
	lhs: ^ElnaInstructionList;
	rhs: ^ElnaInstructionList;
begin
	lhs := elna_rtl_load_operand_value(tac_instruction, 2, ElnaRtlRegister.t2);
	rhs := elna_rtl_load_operand_value(tac_instruction, 3, ElnaRtlRegister.t3);

	next_instruction^ := lhs^.next;
	if next_instruction^ = 0 then
		lhs^.next := rhs
	else
		next_instruction^^ := rhs
	end;
	next_instruction^ := rhs^.next;
	if next_instruction^ = 0 then
		next_instruction^ := rhs
	end;

	return lhs
end;

proc elna_rtl_binary_arithmetic(tac_instruction: Word, next_instruction: Word, operation: Word);
var
	lhs: Word;
	binary_result: Word;
	intermediate_instruction: ^ElnaInstructionList;
begin
	lhs := elna_rtl_binary_operands(tac_instruction, next_instruction);
	binary_result := elna_rtl_instruction_create(operation);

	elna_rtl_copy_operand(tac_instruction, 1, binary_result);
	elna_rtl_instruction_set_operand(binary_result, 2, ElnaRtlOperand.register, ElnaRtlRegister.t2, 0);
	elna_rtl_instruction_set_operand(binary_result, 3, ElnaRtlOperand.register, ElnaRtlRegister.t3, 0);
	elna_rtl_instruction_set_kind(binary_result, operation);

	intermediate_instruction := next_instruction^;
	intermediate_instruction^.next := binary_result;
	next_instruction^ := binary_result;

	return lhs
end;

proc elna_rtl_binary_equality(tac_instruction: Word, instruction_kind: Word, next_instruction: Word);
var
	operands: Word;
	intermediate_instruction: ^ElnaInstructionList;
	operating_instruction: ^ElnaInstructionList;
	binary_result: Word;
begin
	operands := elna_rtl_binary_operands(tac_instruction, next_instruction);
	operating_instruction := elna_rtl_instruction_create(ElnaRtlOperator._xor);

	elna_rtl_instruction_set_operand(operating_instruction, 1, ElnaRtlOperand.register, ElnaRtlRegister.t2, 0);
	elna_rtl_instruction_set_operand(operating_instruction, 2, ElnaRtlOperand.register, ElnaRtlRegister.t2, 0);
	elna_rtl_instruction_set_operand(operating_instruction, 3, ElnaRtlOperand.register, ElnaRtlRegister.t3, 0);

	intermediate_instruction := next_instruction^;
	intermediate_instruction^.next := operating_instruction;

	binary_result := elna_rtl_instruction_create(instruction_kind);
	elna_rtl_copy_operand(tac_instruction, 1, binary_result);
	elna_rtl_instruction_set_operand(binary_result, 2, ElnaRtlOperand.register, ElnaRtlRegister.t2, 0);

	intermediate_instruction := next_instruction^;
	operating_instruction^.next := binary_result;
	next_instruction^ := binary_result;

	return operands
end;

proc elna_rtl_copy_operand(tac_instruction: Word, number: Word, rtl_instruction: Word);
var
	operand_length: Word;
	operand_type: Word;
	operand_value: Word;
begin
	operand_type := _elna_tac_instruction_get_operand_type(tac_instruction, number);
	operand_value := _elna_tac_instruction_get_operand_value(tac_instruction, number);
	operand_length := _elna_tac_instruction_get_operand_length(tac_instruction, number);

	elna_rtl_instruction_set_operand(rtl_instruction, number, operand_type, operand_value, operand_length)
end;

proc elna_rtl_conditional_jump(tac_instruction: Word, condition: Word);
var
	result: Word;
begin
	result := elna_rtl_instruction_create(condition);
	elna_rtl_copy_operand(tac_instruction, 1, result);
	elna_rtl_copy_operand(tac_instruction, 2, result);

	return result
end;

proc elna_rtl_unary(tac_instruction: Word, rtl_operator: Word, next_instruction: Word);
var
	result: ^ElnaInstructionList;
begin
	result := elna_rtl_load_operand_value(tac_instruction, 2, ElnaRtlRegister.t0);
	next_instruction^ := elna_rtl_instruction_create(rtl_operator);
	elna_rtl_copy_operand(tac_instruction, 1, result);
	elna_rtl_instruction_set_operand(result, 2, ElnaRtlOperand.register, ElnaRtlRegister.t0);
	result^.next := next_instruction^;

	return result
end;

proc elna_rtl_call(tac_instruction: Word, next_instruction: ^^ElnaInstructionList);
var
	argument_count: Word;
	current_argument: Word;
	argument_type: Word;
	argument_value: Word;
	argument_length: Word;
	argument_move: Word;
	current_register: Word;
	first_instruction: Word;
	current_instruction: Word;
	name: Word;
	name_length: Word;
begin
	current_register := 0;
	first_instruction := nil;

	current_argument := _elna_tac_instruction_get_operand_value(tac_instruction, 2);
	argument_count := _elna_tac_instruction_get_operand_length(tac_instruction, 2);

	name := _elna_tac_instruction_get_operand_value(tac_instruction, 1);
	name_length := _elna_tac_instruction_get_operand_length(tac_instruction, 1);

	.elna_rtl_call_loop;

	if argument_count > 0 then
		argument_count := argument_count - 1;

		argument_type := current_argument^;
		current_argument := current_argument + 4;
		argument_value := current_argument^;
		current_argument := current_argument + 4;
		argument_length := current_argument^;
		current_argument := current_argument + 4;

		argument_move := elna_rtl_instruction_create(ElnaRtlOperator.move);
		elna_rtl_instruction_set_operand(argument_move, 1, ElnaRtlOperand.register, ElnaRtlRegister.a0 + current_register, 0);
		elna_rtl_instruction_set_operand(argument_move, 2, argument_type, argument_value, argument_length);

		if first_instruction = nil then
			first_instruction := argument_move
		else
			elna_instruction_list_concatenate(current_instruction, argument_move)
		end;
		current_instruction := argument_move;

		current_register := current_register + 1;

		goto elna_rtl_call_loop
	end;
	argument_move := elna_rtl_instruction_create(ElnaRtlOperator.jal);
	elna_rtl_copy_operand(tac_instruction, 1, argument_move);

	if first_instruction = nil then
		first_instruction := argument_move
	else
		elna_instruction_list_concatenate(current_instruction, argument_move)
	end;
	current_instruction := argument_move;

	argument_type := _elna_tac_instruction_get_operand_type(tac_instruction, 3);
	argument_value := _elna_tac_instruction_get_operand_value(tac_instruction, 3);
	argument_length := _elna_tac_instruction_get_operand_length(tac_instruction, 3);
	argument_move := elna_rtl_instruction_create(ElnaRtlOperator.move);
	elna_rtl_instruction_set_operand(argument_move, 1, argument_type, argument_value, argument_length);
	elna_rtl_instruction_set_operand(argument_move, 2, ElnaRtlOperand.register, ElnaRtlRegister.a0, 0);
	elna_instruction_list_concatenate(current_instruction, argument_move);

	next_instruction^ := argument_move;

	return first_instruction
end;

proc elna_rtl_store(tac_instruction: Word, next_instruction: ^^ElnaInstructionList);
var
	result: ^ElnaInstructionList;
	operand_type: Word;
	operand_value: Word;
	operand_length: Word;
	operands: ^ElnaInstructionList;
begin
	operands := elna_rtl_load_operand_value(tac_instruction, 1, ElnaRtlRegister.t0);
	next_instruction^ := elna_rtl_instruction_create(ElnaRtlOperator.sw);
	result := operands;
	operands := result^.next;

	elna_rtl_instruction_set_operand(next_instruction^, 1, ElnaRtlOperand.register, ElnaRtlRegister.t0, 0);

	operand_type := _elna_tac_instruction_get_operand_type(tac_instruction, 2);
	operand_value := _elna_tac_instruction_get_operand_value(tac_instruction, 2);
	operand_length := _elna_tac_instruction_get_operand_length(tac_instruction, 2);
	if operand_type = ElnaTacOperand.pseudo then
		elna_rtl_instruction_set_operand(next_instruction^, 2, ElnaRtlOperand.pseudo, operand_value, operand_length)
	end;
	if operands = 0 then
		result^.next := next_instruction^
	else
		operands^.next := next_instruction^
	end;
	return result
end;

proc elna_rtl_load(tac_instruction: Word, next_instruction: ^^ElnaInstructionList);
var
	result: ^ElnaInstructionList;
	operand_type: Word;
	operand_value: Word;
	operand_length: Word;
	operands: ^ElnaInstructionList;
begin
	operands := elna_rtl_load_operand_value(tac_instruction, 1, ElnaRtlRegister.t0);
	next_instruction^ := elna_rtl_instruction_create(ElnaRtlOperator.lw);
	result := operands;
	operands := result^.next;

	elna_rtl_instruction_set_operand(next_instruction^, 2, ElnaRtlOperand.offset, ElnaRtlRegister.t0, 0);

	operand_type := _elna_tac_instruction_get_operand_type(tac_instruction, 2);
	operand_value := _elna_tac_instruction_get_operand_value(tac_instruction, 2);
	operand_length := _elna_tac_instruction_get_operand_length(tac_instruction, 2);
	elna_rtl_instruction_set_operand(next_instruction^, 1, operand_type, operand_value, operand_length);

	if operands = 0 then
		result^.next := next_instruction^
	else
		operands^.next := next_instruction^
	end;
	return result
end;

proc elna_rtl_instruction(tac_instruction: Word, next_instruction: ^^ElnaInstructionList);
var
	result: ^ElnaInstructionList;
	instruction_kind: Word;
	operand_type: Word;
	operand_value: Word;
	operand_length: Word;
	operands: ^ElnaInstructionList;
	intermediate_instruction: ^ElnaInstructionList;
begin
	result := malloc(elna_rtl_instruction_size());
	instruction_kind := _elna_tac_instruction_get_kind(tac_instruction);
	next_instruction^ := nil;

	if instruction_kind = ElnaTacOperator.get_address then
		result := elna_rtl_instruction_create(ElnaRtlOperator.la);

		elna_rtl_copy_operand(tac_instruction, 1, result);
		elna_rtl_copy_operand(tac_instruction, 2, result)
	elsif instruction_kind = ElnaTacOperator.add then
		result := elna_rtl_binary_arithmetic(tac_instruction, next_instruction, ElnaRtlOperator.add)
	elsif instruction_kind = ElnaTacOperator.load then
		result := elna_rtl_load(tac_instruction, next_instruction)
	elsif instruction_kind = ElnaTacOperator.store then
		result := elna_rtl_store(tac_instruction, next_instruction)
	elsif instruction_kind = ElnaTacOperator.proc_call then
		result := elna_rtl_call(tac_instruction, next_instruction)
	elsif instruction_kind = ElnaTacOperator.subtract then
		result := elna_rtl_binary_arithmetic(tac_instruction, next_instruction, ElnaRtlOperator.sub)
	elsif instruction_kind = ElnaTacOperator.multiply then
		result := elna_rtl_binary_arithmetic(tac_instruction, next_instruction, ElnaRtlOperator.mul)
	elsif instruction_kind = ElnaTacOperator.divide then
		result := elna_rtl_binary_arithmetic(tac_instruction, next_instruction, ElnaRtlOperator.div)
	elsif instruction_kind = ElnaTacOperator.remainder then
		result := elna_rtl_binary_arithmetic(tac_instruction, next_instruction, ElnaRtlOperator.rem)
	elsif instruction_kind = ElnaTacOperator._xor then
		result := elna_rtl_binary_arithmetic(tac_instruction, next_instruction, ElnaRtlOperator._xor)
	elsif instruction_kind = ElnaTacOperator._or then
		result := elna_rtl_binary_arithmetic(tac_instruction, next_instruction, ElnaRtlOperator._or)
	elsif instruction_kind = ElnaTacOperator.and then
		result := elna_rtl_binary_arithmetic(tac_instruction, next_instruction, ElnaRtlOperator.and)
	elsif instruction_kind = ElnaTacOperator.less_than then
		result := elna_rtl_binary_arithmetic(tac_instruction, next_instruction, ElnaRtlOperator.slt)
	elsif instruction_kind = ElnaTacOperator.greater_than then
		operands := elna_rtl_binary_operands(tac_instruction, next_instruction);

		result := elna_rtl_instruction_create(ElnaRtlOperator.slt);
		elna_rtl_copy_operand(tac_instruction, 1, result);
		elna_rtl_instruction_set_operand(result, 2, ElnaRtlOperand.register, ElnaRtlRegister.t3, 0);
		elna_rtl_instruction_set_operand(result, 3, ElnaRtlOperand.register, ElnaRtlRegister.t2, 0);

		intermediate_instruction := next_instruction^;
		intermediate_instruction^.next := result;
		next_instruction^ := result;

		result := operands;
		elna_rtl_instruction_set_kind(next_instruction^, ElnaRtlOperator.slt)
	elsif instruction_kind = ElnaTacOperator.less_or_equal then
		operands := elna_rtl_binary_operands(tac_instruction, next_instruction);
		intermediate_instruction := elna_rtl_instruction_create(ElnaRtlOperator.slt);

		elna_rtl_instruction_set_operand(intermediate_instruction, 1, ElnaRtlOperand.register, ElnaRtlRegister.t2, 0);
		elna_rtl_instruction_set_operand(intermediate_instruction, 2, ElnaRtlOperand.register, ElnaRtlRegister.t3, 0);
		elna_rtl_instruction_set_operand(intermediate_instruction, 3, ElnaRtlOperand.register, ElnaRtlRegister.t2, 0);
		result := next_instruction^;
		result^.next := intermediate_instruction;
		next_instruction^ := intermediate_instruction;

		result := elna_rtl_instruction_create(ElnaRtlOperator.xori);
		elna_rtl_copy_operand(tac_instruction, 1, result);
		elna_rtl_instruction_set_operand(result, 2, ElnaRtlOperand.register, ElnaRtlRegister.t2, 0);
		elna_rtl_instruction_set_operand(result, 3, ElnaRtlOperand.immediate, 1, 0);
		intermediate_instruction := next_instruction^;
		intermediate_instruction^.next := result;
		next_instruction^ := result;
		result := operands
	elsif instruction_kind = ElnaTacOperator.greater_or_equal then
		operands := elna_rtl_binary_operands(tac_instruction, next_instruction);
		intermediate_instruction := elna_rtl_instruction_create(ElnaRtlOperator.slt);

		elna_rtl_instruction_set_operand(intermediate_instruction, 1, ElnaRtlOperand.register, ElnaRtlRegister.t2, 0);
		elna_rtl_instruction_set_operand(intermediate_instruction, 2, ElnaRtlOperand.register, ElnaRtlRegister.t2, 0);
		elna_rtl_instruction_set_operand(intermediate_instruction, 3, ElnaRtlOperand.register, ElnaRtlRegister.t3, 0);
		result := next_instruction^;
		result^.next := intermediate_instruction;
		next_instruction^ := intermediate_instruction;

		result := elna_rtl_instruction_create(ElnaRtlOperator.xori);
		elna_rtl_copy_operand(tac_instruction, 1, result);
		elna_rtl_instruction_set_operand(result, 2, ElnaRtlOperand.register, ElnaRtlRegister.t2, 0);
		elna_rtl_instruction_set_operand(result, 3, ElnaRtlOperand.immediate, 1, 0);
		intermediate_instruction := next_instruction^;
		intermediate_instruction^.next := result;
		next_instruction^ := result;
		result := operands
	elsif instruction_kind = ElnaTacOperator.equal then
		result := elna_rtl_binary_equality(tac_instruction, ElnaRtlOperator.seqz, next_instruction)
	elsif instruction_kind = ElnaTacOperator.not_equal then
		result := elna_rtl_binary_equality(tac_instruction, ElnaRtlOperator.snez, next_instruction)
	elsif instruction_kind = ElnaTacOperator.negate then
		result := elna_rtl_unary(tac_instruction, ElnaRtlOperator.neg, next_instruction)
	elsif instruction_kind = ElnaTacOperator.complement then
		result := elna_rtl_unary(tac_instruction, ElnaRtlOperator.not, next_instruction)
	elsif instruction_kind = ElnaTacOperator.jump then
		result := elna_rtl_instruction_create(ElnaRtlOperator.j);
		elna_rtl_copy_operand(tac_instruction, 1, result)
	elsif instruction_kind = ElnaTacOperator.jump_if_zero then
		result := elna_rtl_conditional_jump(tac_instruction, ElnaRtlOperator.beqz)
	elsif instruction_kind = ElnaTacOperator.jump_if_not_zero then
		result := elna_rtl_conditional_jump(tac_instruction, ElnaRtlOperator.bnez)
	elsif instruction_kind = ElnaTacOperator._return then
		result := elna_rtl_load_operand_value(tac_instruction, 1, ElnaRtlRegister.a0)
	elsif instruction_kind = ElnaTacOperator.label then
		result := elna_rtl_instruction_create(ElnaRtlOperator.label);
		elna_rtl_copy_operand(tac_instruction, 1, result)
	elsif instruction_kind = ElnaTacOperator.copy then
		operand_type := _elna_tac_instruction_get_operand_type(tac_instruction, 1);
		operand_value := _elna_tac_instruction_get_operand_value(tac_instruction, 1);
		operand_length := _elna_tac_instruction_get_operand_length(tac_instruction, 1);

		if operand_type = ElnaTacOperand.pseudo then
			operands := elna_rtl_load_operand_value(tac_instruction, 2, ElnaRtlRegister.t4);
			result := operands;
			operands := result^.next;

			next_instruction^ := elna_rtl_instruction_create(ElnaRtlOperator.move);
			_elna_tac_instruction_set_operand(next_instruction^, 1, ElnaRtlOperand.pseudo, operand_value, operand_length);
			_elna_tac_instruction_set_operand(next_instruction^, 2, ElnaRtlOperand.register, ElnaRtlRegister.t4, 0);

			if operands = nil then
				result^.next := next_instruction^
			else
				operands^.next := next_instruction^
			end
		end
	end;
	if next_instruction^ = nil then
		next_instruction^ := result;
	end;
	return result
end;

proc elna_instruction_module_create(data: Word, code: Word);
var
	result: ^ElnaInstructionModule;
begin
	result := malloc(#size(ElnaInstructionModule));

	result^.data := data;
	result^.code := code;

	return result
end;

proc elna_tac_label(counter: Word, length: Word);
var
	result1: Word;
begin
	result1 := _elna_tac_instruction_create(ElnaTacOperator.label);

	_elna_tac_instruction_set_operand(result1, 1, ElnaTacOperand.symbol, counter, length);

	return result1
end;

proc elna_riscv_instruction_name(instruction_kind: Word);
var
	argument_count: Word;
begin
	if instruction_kind = ElnaRtlOperator.li then
		argument_count := 2;
		_write_s("\tli", 3)
	elsif instruction_kind = ElnaRtlOperator.la then
		argument_count := 2;
		_write_s("\tla", 3)
	elsif instruction_kind = ElnaRtlOperator.add then
		argument_count := 3;
		_write_s("\tadd", 4)
	elsif instruction_kind = ElnaRtlOperator.addi then
		argument_count := 3;
		_write_s("\taddi", 5)
	elsif instruction_kind = ElnaRtlOperator.lw then
		argument_count := 2;
		_write_s("\tlw", 3)
	elsif instruction_kind = ElnaRtlOperator.sw then
		argument_count := 2;
		_write_s("\tsw", 3)
	elsif instruction_kind = ElnaRtlOperator.jal then
		argument_count := 1;
		_write_s("\tcall", 5)
	elsif instruction_kind = ElnaRtlOperator.move then
		argument_count := 2;
		_write_s("\tmv", 3)
	elsif instruction_kind = ElnaRtlOperator.sub then
		argument_count := 3;
		_write_s("\tsub", 4)
	elsif instruction_kind = ElnaRtlOperator.mul then
		argument_count := 3;
		_write_s("\tmul", 4)
	elsif instruction_kind = ElnaRtlOperator.div then
		argument_count := 3;
		_write_s("\tdiv", 4)
	elsif instruction_kind = ElnaRtlOperator.rem then
		argument_count := 3;
		_write_s("\trem", 4)
	elsif instruction_kind = ElnaRtlOperator._xor then
		argument_count := 3;
		_write_s("\txor", 4)
	elsif instruction_kind = ElnaRtlOperator.xori then
		argument_count := 3;
		_write_s("\txori", 5)
	elsif instruction_kind = ElnaRtlOperator._or then
		argument_count := 3;
		_write_s("\tor", 3)
	elsif instruction_kind = ElnaRtlOperator.and then
		argument_count := 3;
		_write_s("\tand", 4)
	elsif instruction_kind = ElnaRtlOperator.seqz then
		argument_count := 2;
		_write_s("\tseqz", 5)
	elsif instruction_kind = ElnaRtlOperator.snez then
		argument_count := 2;
		_write_s("\tsnez", 5)
	elsif instruction_kind = ElnaRtlOperator.slt then
		argument_count := 3;
		_write_s("\tslt", 4)
	elsif instruction_kind = ElnaRtlOperator.neg then
		argument_count := 2;
		_write_s("\tneg", 4)
	elsif instruction_kind = ElnaRtlOperator.not then
		argument_count := 2;
		_write_s("\tnot", 4)
	elsif instruction_kind = ElnaRtlOperator.j then
		argument_count := 1;
		_write_s("\tj", 2)
	elsif instruction_kind = ElnaRtlOperator.beqz then
		argument_count := 2;
		_write_s("\tbeqz", 5)
	elsif instruction_kind = ElnaRtlOperator.bnez then
		argument_count := 2;
		_write_s("\tbnez", 5)
	end;
	return argument_count
end;

proc elna_riscv_register(register: Word);
begin
	_write_c('x');
	_write_i(register - 1)
end;

proc elna_riscv_operand(instruction: Word, n: Word);
var
	operand_value: Word;
	operand_length: Word;
	operand_type: Word;
begin
	operand_type := elna_rtl_instruction_get_operand_type(instruction, n);
	operand_value := elna_rtl_instruction_get_operand_value(instruction, n);
	operand_length := elna_rtl_instruction_get_operand_length(instruction, n);

	_write_c(' ');
	if operand_type = ElnaRtlOperand.register then
		elna_riscv_register(operand_value)
	elsif operand_type = ElnaRtlOperand.offset then
		_write_i(operand_length);
		_write_c('(');
		elna_riscv_register(operand_value);
		_write_c(')')
	elsif operand_type = ElnaRtlOperand.symbol then
		if operand_length = 0 then
			_write_label(operand_value, 0)
		else
			_write_s(operand_value, operand_length)
		end
	elsif operand_length = 0 then (* ElnaRtlOperand.immediate *)
		_write_i(operand_value)
	else
		_write_s(operand_value, operand_length)
	end
end;

proc elna_alloc_variable(operand_value: Word, operand_length: Word);
var
	pseudo_symbol1: Word;
begin
	pseudo_symbol1 := _symbol_table_lookup(@variable_map, operand_value, operand_length);
	if pseudo_symbol1 = nil then
		_symbol_table_enter(@variable_map, operand_value, operand_length, temporary_variable_counter);
		pseudo_symbol1 := temporary_variable_counter;
		temporary_variable_counter := temporary_variable_counter + 4
	end;
	return pseudo_symbol1
end;

(**
  * If the first operand of an instruction is an operation target and expected
  * to be a register, but is not a register, then this procedure rewrites it
  * to a temporary register and preserves its value in the following instruction.
  *)
proc elna_alloc_operation_target(instruction: ^ElnaInstructionList);
var
	operand_type: Word;
	operand_value: Word;
	operand_length: Word;
	pseudo_symbol: Word;
	store_instruction: ^ElnaInstructionList;
begin
	operand_type := elna_rtl_instruction_get_operand_type(instruction, 1);
	operand_value := elna_rtl_instruction_get_operand_value(instruction, 1);
	operand_length := elna_rtl_instruction_get_operand_length(instruction, 1);

	if operand_type = ElnaRtlOperand.pseudo then
		store_instruction := elna_rtl_instruction_create(ElnaRtlOperator.sw);
		store_instruction^.next := instruction^.next;

		pseudo_symbol := elna_alloc_variable(operand_value, operand_length);
		elna_rtl_instruction_set_operand(store_instruction, 1, ElnaRtlOperand.register, ElnaRtlRegister.t0, 0);
		elna_rtl_instruction_set_operand(store_instruction, 2, ElnaRtlOperand.offset, ElnaRtlRegister.sp, pseudo_symbol);

		instruction^.next := store_instruction;
		elna_rtl_instruction_set_operand(instruction, 1, ElnaRtlOperand.register, ElnaRtlRegister.t0, 0)
	end
end;

proc elna_alloc_load_address(instruction: ^ElnaInstructionList);
var
	operand_type: Word;
	operand_value: Word;
	operand_length: Word;
	pseudo_symbol: Word;
begin
	operand_type := elna_rtl_instruction_get_operand_type(instruction, 2);
	operand_value := elna_rtl_instruction_get_operand_value(instruction, 2);
	operand_length := elna_rtl_instruction_get_operand_length(instruction, 2);

	if operand_type = ElnaRtlOperand.pseudo then
		pseudo_symbol := elna_alloc_variable(operand_value, operand_length);
		elna_rtl_instruction_set_kind(instruction, ElnaRtlOperator.addi);

		elna_rtl_instruction_set_operand(instruction, 2, ElnaRtlOperand.register, ElnaRtlRegister.sp, 0);
		elna_rtl_instruction_set_operand(instruction, 3, ElnaRtlOperand.immediate, pseudo_symbol, 0)
	end;
	operand_type := elna_rtl_instruction_get_operand_type(instruction, 1);

	if operand_type = ElnaRtlOperand.pseudo then
		elna_alloc_operation_target(instruction)
	end
end;

proc elna_alloc_store(instruction: ^ElnaInstructionList);
var
	old_instruction: ^ElnaInstructionList;
	operand_type: Word;
	operand_value: Word;
	operand_length: Word;
	pseudo_symbol: Word;
begin
	operand_type := elna_rtl_instruction_get_operand_type(instruction, 2);
	operand_value := elna_rtl_instruction_get_operand_value(instruction, 2);
	operand_length := elna_rtl_instruction_get_operand_length(instruction, 2);

	if operand_type = ElnaRtlOperand.pseudo then
		old_instruction := malloc(elna_rtl_instruction_size());
		memcpy(old_instruction, instruction, elna_rtl_instruction_size());

		pseudo_symbol := elna_alloc_variable(operand_value, operand_length);
		elna_rtl_instruction_set_kind(instruction, ElnaRtlOperator.lw);

		elna_rtl_instruction_set_operand(instruction, 1, ElnaRtlOperand.register, ElnaRtlRegister.t1, 0);
		elna_rtl_instruction_set_operand(instruction, 2, ElnaRtlOperand.offset, ElnaRtlRegister.sp, pseudo_symbol);

		instruction^.next := old_instruction;
		elna_rtl_instruction_set_operand(old_instruction, 2, ElnaRtlOperand.offset, ElnaRtlRegister.t1, 0)
	end
end;

proc elna_alloc_load(instruction: ^ElnaInstructionList);
var
	old_instruction: ^ElnaInstructionList;
	operand_type: Word;
	operand_value: Word;
	operand_length: Word;
	pseudo_symbol: Word;
begin
	operand_type := elna_rtl_instruction_get_operand_type(instruction, 1);
	operand_value := elna_rtl_instruction_get_operand_value(instruction, 1);
	operand_length := elna_rtl_instruction_get_operand_length(instruction, 1);

	if operand_type = ElnaRtlOperand.pseudo then
		old_instruction := malloc(elna_rtl_instruction_size());
		memcpy(old_instruction, instruction, elna_rtl_instruction_size());

		pseudo_symbol := elna_alloc_variable(operand_value, operand_length);
		elna_rtl_instruction_set_kind(old_instruction, ElnaRtlOperator.sw);

		elna_rtl_instruction_set_operand(old_instruction, 1, ElnaRtlOperand.register, ElnaRtlRegister.t1, 0);
		elna_rtl_instruction_set_operand(old_instruction, 2, ElnaRtlOperand.offset, ElnaRtlRegister.sp, pseudo_symbol);

		instruction^.next := old_instruction;
		elna_rtl_instruction_set_operand(instruction, 1, ElnaRtlOperand.register, ElnaRtlRegister.t1, 0)
	end
end;

proc elna_alloc_instruction(instruction: ^ElnaInstructionList);
var
	instruction_kind: Word;
	operand_type: Word;
	operand_value: Word;
	operand_length: Word;
	pseudo_symbol: Word;
	old_instruction: ^ElnaInstructionList;
begin
	instruction_kind := elna_rtl_instruction_get_kind(instruction);

	if instruction_kind = ElnaRtlOperator.move then
		operand_type := elna_rtl_instruction_get_operand_type(instruction, 1);
		operand_value := elna_rtl_instruction_get_operand_value(instruction, 1);
		operand_length := elna_rtl_instruction_get_operand_length(instruction, 1);

		if operand_type = ElnaRtlOperand.pseudo then
			pseudo_symbol := elna_alloc_variable(operand_value, operand_length);
			elna_rtl_instruction_set_kind(instruction, ElnaRtlOperator.sw);

			operand_type := elna_rtl_instruction_get_operand_type(instruction, 2);
			operand_value := elna_rtl_instruction_get_operand_value(instruction, 2);
			operand_length := elna_rtl_instruction_get_operand_length(instruction, 2);

			elna_rtl_instruction_set_operand(instruction, 1, operand_type, operand_value, operand_length);
			elna_rtl_instruction_set_operand(instruction, 2, ElnaRtlOperand.offset, ElnaRtlRegister.sp, pseudo_symbol);

			goto elna_alloc_instruction_end
		end;

		operand_type := elna_rtl_instruction_get_operand_type(instruction, 2);
		operand_value := elna_rtl_instruction_get_operand_value(instruction, 2);
		operand_length := elna_rtl_instruction_get_operand_length(instruction, 2);

		if operand_type = ElnaRtlOperand.pseudo then
			pseudo_symbol := elna_alloc_variable(operand_value, operand_length);
			elna_rtl_instruction_set_kind(instruction, ElnaRtlOperator.lw);
			elna_rtl_instruction_set_operand(instruction, 2, ElnaRtlOperand.offset, ElnaRtlRegister.sp, pseudo_symbol);

			goto elna_alloc_instruction_end
		end
	elsif instruction_kind = ElnaRtlOperator.la then
		elna_alloc_load_address(instruction)
	elsif instruction_kind = ElnaRtlOperator.lw then
		elna_alloc_load(instruction)
	elsif instruction_kind = ElnaRtlOperator.sw then
		elna_alloc_store(instruction)
	elsif instruction_kind = ElnaRtlOperator._or then
		elna_alloc_operation_target(instruction)
	elsif instruction_kind = ElnaRtlOperator.and then
		elna_alloc_operation_target(instruction)
	elsif instruction_kind = ElnaRtlOperator.mul then
		elna_alloc_operation_target(instruction)
	elsif instruction_kind = ElnaRtlOperator.sub then
		elna_alloc_operation_target(instruction)
	elsif instruction_kind = ElnaRtlOperator.add then
		elna_alloc_operation_target(instruction)
	elsif instruction_kind = ElnaRtlOperator._xor then
		elna_alloc_operation_target(instruction)
	elsif instruction_kind = ElnaRtlOperator.rem then
		elna_alloc_operation_target(instruction)
	elsif instruction_kind = ElnaRtlOperator.slt then
		elna_alloc_operation_target(instruction)
	elsif instruction_kind = ElnaRtlOperator.beqz then
		operand_type := elna_rtl_instruction_get_operand_type(instruction, 1);
		operand_value := elna_rtl_instruction_get_operand_value(instruction, 1);
		operand_length := elna_rtl_instruction_get_operand_length(instruction, 1);

		if operand_type = ElnaRtlOperand.pseudo then
			old_instruction := malloc(elna_rtl_instruction_size());
			memcpy(old_instruction, instruction, elna_rtl_instruction_size());

			pseudo_symbol := elna_alloc_variable(operand_value, operand_length);
			elna_rtl_instruction_set_kind(instruction, ElnaRtlOperator.lw);

			elna_rtl_instruction_set_operand(instruction, 1, ElnaRtlOperand.register, ElnaRtlRegister.t0, 0);
			elna_rtl_instruction_set_operand(instruction, 2, ElnaRtlOperand.offset, ElnaRtlRegister.sp, pseudo_symbol);

			instruction^.next := old_instruction;
			elna_rtl_instruction_set_operand(old_instruction, 1, ElnaRtlOperand.register, ElnaRtlRegister.t0, 0);

			goto elna_alloc_instruction_end
		end
	elsif instruction_kind = ElnaRtlOperator.seqz then
		elna_alloc_operation_target(instruction)
	elsif instruction_kind = ElnaRtlOperator.snez then
		elna_alloc_operation_target(instruction)
	elsif instruction_kind = ElnaRtlOperator.xori then
		elna_alloc_operation_target(instruction)
	end;
	.elna_alloc_instruction_end;
end;

proc elna_riscv_instruction(instruction: Word);
var
	argument_count: Word;
	instruction_kind: Word;
	current_argument: Word;
	operand_value: Word;
	operand_length: Word;
begin
	instruction_kind := elna_rtl_instruction_get_kind(instruction);
	argument_count := 0;

	if instruction_kind = ElnaRtlOperator.label then
		operand_value := elna_rtl_instruction_get_operand_value(instruction, 1);
		operand_length := elna_rtl_instruction_get_operand_length(instruction, 1);
		_write_label(operand_value, operand_length);
		_write_c(':')
	elsif instruction_kind = ElnaRtlOperator.allocate_stack then
		operand_value := elna_rtl_instruction_get_operand_value(instruction, 1);

		(* Write the prologue. *)
		printf("\taddi sp, sp, -%i\n\tsw ra, %i(sp)\n\tsw s0, %i(sp)\n\taddi s0, sp, %i\n\0",
				operand_value + 8, operand_value + 4, operand_value, operand_value + 8);
		fflush(nil)
	elsif instruction_kind = ElnaRtlOperator.ret then
		operand_value := elna_rtl_instruction_get_operand_value(instruction, 1);

		(* Write the epilogue. *)
		printf("\tlw ra, %i(sp)\n\tlw s0, %i(sp)\n\taddi sp, sp, %i\n\0", operand_value + 4, operand_value, operand_value + 8);
		fflush(nil)
	else
		argument_count := elna_riscv_instruction_name(instruction_kind)
	end;
	current_argument := 1;

	.elna_riscv_instruction_loop;
	if current_argument <= argument_count then
		elna_riscv_operand(instruction, current_argument);
		current_argument := current_argument + 1
	end;
	if current_argument <= argument_count then
		_write_c(',');
		goto elna_riscv_instruction_loop
	end;

	_write_c('\n')
end;

proc elna_rtl_instructions(instruction: ^ElnaInstructionList);
var
	last_copy1: ^ElnaInstructionList;
	current_copy: ^ElnaInstructionList;
	next_copy: ^ElnaInstructionList;
	first_copy: ^ElnaInstructionList;
begin
	if instruction <> nil then
		first_copy := elna_rtl_instruction(instruction, @current_copy);
		instruction := instruction^.next
	else
		first_copy := nil;
		current_copy := nil
	end;
	.elna_rtl_instructions_start;

	if instruction <> nil then
		next_copy := elna_rtl_instruction(instruction, @last_copy1);

		instruction := instruction^.next;
		current_copy^.next := next_copy;
		current_copy := last_copy1;
		goto elna_rtl_instructions_start
	end;

	return first_copy
end;

proc elna_alloc_instructions(instruction: ^ElnaInstructionList);
begin
	.elna_alloc_instructions_start;

	if instruction <> nil then
		elna_alloc_instruction(instruction);
		instruction := instruction^.next;
		goto elna_alloc_instructions_start
	end
end;

proc elna_riscv_instructions(instruction: ^ElnaInstructionList);
begin
	.elna_riscv_instructions_start;
	if instruction <> nil then
		elna_riscv_instruction(instruction);
		instruction := instruction^.next;
		goto elna_riscv_instructions_start
	end
end;

proc elna_alloc_procedure(rtl_declaration: ^ElnaInstructionDeclaration);
var
	stack_instruction: ^ElnaInstructionList;
begin
	.elna_alloc_procedure_loop;
	temporary_variable_counter := 4;
	variable_map := 0;

	elna_alloc_instructions(rtl_declaration^.body);
	if rtl_declaration^.stack then
		stack_instruction := elna_rtl_instruction_create(ElnaRtlOperator.allocate_stack);
		stack_instruction^.next := rtl_declaration^.body;
		elna_rtl_instruction_set_operand(stack_instruction, 1, ElnaRtlOperand.immediate, temporary_variable_counter, 0);

		rtl_declaration^.body := stack_instruction;
		stack_instruction := elna_rtl_instruction_create(ElnaRtlOperator.ret);
		elna_rtl_instruction_set_operand(stack_instruction, 1, ElnaRtlOperand.immediate, temporary_variable_counter, 0);

		elna_instruction_list_concatenate(rtl_declaration^.body, stack_instruction)
	end;

	rtl_declaration := rtl_declaration^.next;
	if rtl_declaration <> nil then
		goto elna_alloc_procedure_loop
	end
end;

proc elna_riscv_procedure(procedure: ^ElnaInstructionDeclaration);
begin
	.elna_riscv_procedure_loop;

	(* Write .type _procedure_name, @function. *)
	_write_z(".type \0");

	_write_s(procedure^.name, procedure^.length);
	_write_z(", @function\n\0");

	(* Write procedure label, _procedure_name: *)
	_write_s(procedure^.name, procedure^.length);
	_write_z(":\n\0");

	elna_riscv_instructions(procedure^.body);
	_write_z("\tret\n\0");

	procedure := procedure^.next;
	if procedure <> nil then
		goto elna_riscv_procedure_loop
	end
end;

proc elna_riscv_variable(variable: ^ElnaInstructionDeclaration);
begin
	.elna_riscv_variable_loop;
	if variable <> 0 then
		_write_z(".type \0");
		_write_s(variable^.name, variable^.length);
		_write_z(", @object\n\0");

		_write_s(variable^.name, variable^.length);
		_write_c(':');

		_write_z(" .zero \0");
		_write_i(variable^.body);

		_write_c('\n');
		variable := variable^.next;

		goto elna_riscv_variable_loop
	end
end;

proc elna_rtl_module_declaration(tac_module: ^ElnaInstructionModule);
var
	code_part: Word;
	data_part: Word;
begin
	data_part := elna_rtl_globals(tac_module^.data);
	code_part := elna_rtl_procedures(tac_module^.code);

	return elna_instruction_module_create(data_part, code_part)
end;

proc elna_alloc_module(pair: ^ElnaInstructionModule);
begin
	elna_alloc_procedure(pair^.code)
end;

proc elna_riscv_module(pair: ^ElnaInstructionModule);
var
	compiler_strings_copy: Word;
	compiler_strings_end: Word;
	current_byte: Word;
begin
	_write_z(".globl main\n\n\0");
	_write_z(".section .data\n\0");

	elna_riscv_variable(pair^.data);

	_write_z(".section .text\n\n\0");
	_write_z(".type _load_byte, @function\n_load_byte:\n\tlb a0, (a0)\nret\n\n\0");
	_write_z(".type _store_byte, @function\n_store_byte:\n\tsb a0, (a1)\nret\n\n\0");

	elna_riscv_procedure(pair^.code);

	_write_z(".section .rodata\n.type strings, @object\nstrings: .ascii \0");
	_write_c('"');

	compiler_strings_copy := @compiler_strings;
	compiler_strings_end := compiler_strings_position;

	.elna_riscv_module_loop;
	if compiler_strings_copy < compiler_strings_end then
		current_byte := _load_byte(compiler_strings_copy);
		compiler_strings_copy := compiler_strings_copy + 1;
		_write_c(current_byte);

		goto elna_riscv_module_loop
	end;
	_write_c('"');
	_write_c('\n');
end;

proc elna_parser_integer_literal();
var
	integer_token: Word;
	integer_length: Word;
	result: ^ElnaTreeIntegerLiteral;
	buffer: Word;
begin
	result := malloc(#size(ElnaTreeIntegerLiteral));

	integer_token := _elna_lexer_global_get_start();
	integer_length := _elna_lexer_global_get_end() - integer_token;

	_elna_lexer_skip_token();
	buffer := malloc(integer_length + 1);
	bzero(buffer, integer_length + 1);
	memcpy(buffer, integer_token, integer_length);

	result^.kind := ElnaTreeKind.integer_literal;
	result^.value := atoi(buffer);
	result^.type_decoration := nil;

	return result
end;

proc elna_parser_boolean_literal();
var
	boolean_token: Word;
	result: ^ElnaTreeBooleanLiteral;
begin
	result := malloc(#size(ElnaTreeBooleanLiteral));

	boolean_token := _elna_lexer_global_get_start();
	_elna_lexer_skip_token();

	result^.kind := ElnaTreeKind.boolean_literal;
	result^.value := string_compare(boolean_token, 4, "true", 4);
	result^.type_decoration := nil;

	return result
end;

proc elna_parser_nil_literal();
var
	result: ^ElnaTreeNilLiteral;
begin
	_elna_lexer_skip_token();

	result := malloc(#size(ElnaTreeNilLiteral));
	result^.kind := ElnaTreeKind.null;
	result^.type_decoration := nil;

	return result
end;

proc elna_tac_integer_literal(integer_literal_node: ^ElnaTreeIntegerLiteral, operand_type: Word, operand_value: Word, operand_length: Word);
begin
	operand_type^ := ElnaTacOperand.immediate;
	operand_value^ := integer_literal_node^.value;
	operand_length^ := 0;

	return nil
end;

proc elna_tac_boolean_literal(boolean_literal_node: ^ElnaTreeBooleanLiteral, operand_type: Word, operand_value: Word, operand_length: Word);
begin
	operand_type^ := ElnaTacOperand.immediate;
	operand_value^ := boolean_literal_node^.value;
	operand_length^ := 0;

	return nil
end;

proc elna_tac_nil_literal(nil_node: Word, operand_type: Word, operand_value: Word, operand_length: Word);
begin
	operand_type^ := ElnaTacOperand.immediate;
	operand_value^ := 0;
	operand_length^ := 0;

	return nil
end;

proc elna_parser_character_literal();
var
	character: Word;
	character_length: Word;
	result: ^ElnaTreeCharacterLiteral;
begin
	result := malloc(#size(ElnaTreeCharacterLiteral));

	character := _elna_lexer_global_get_start();
	character_length := _elna_lexer_global_get_end();
	character_length := character_length - character;
	_elna_lexer_skip_token();

	result^.kind := ElnaTreeKind.character_literal;
	result^.value := character;
	result^.length := character_length;
	result^.type_decoration := nil;

	return result
end;

proc elna_tac_character_literal(character_literal_node: ^ElnaTreeCharacterLiteral, operand_type: Word, operand_value: Word, operand_length: Word);
begin
	operand_type^ := ElnaTacOperand.immediate;
	operand_value^ := character_literal_node^.value;
	operand_length^ := character_literal_node^.length;

	return nil
end;

proc elna_parser_variable_expression();
var
	name_pointer: Word;
	name_length: Word;
	result: ^ElnaTreeVariableExpression;
begin
	name_pointer := _elna_lexer_global_get_start();
	name_length := _elna_lexer_global_get_end() - name_pointer;
	_elna_lexer_skip_token();

	result := malloc(#size(ElnaTreeVariableExpression));

	result^.kind := ElnaTreeKind.variable_expression;
	result^.name := name_pointer;
	result^.length := name_length;
	result^.type_decoration := nil;

	return result
end;

proc elna_tac_variable_expression(variable_expression: ^ElnaTreeVariableExpression, symbol_table: Word, operand_type: Word, operand_value: Word, operand_length: Word);
var
	lookup_result: ^ElnaSymbolTemporaryInfo;
begin
	lookup_result := _symbol_table_lookup(symbol_table, variable_expression^.name, variable_expression^.length);

	if lookup_result <> nil then
		operand_type^ := ElnaTacOperand.pseudo;
		operand_value^ := variable_expression^.name;
		operand_length^ := variable_expression^.length
	else
		operand_type^ := ElnaTacOperand.symbol;
		operand_value^ := variable_expression^.name;
		operand_length^ := variable_expression^.length
	end;
	return nil
end;

proc elna_parser_string_literal();
var
	length: Word;
	token_start: Word;
	result: ^ElnaTreeStringLiteral;
begin
	result := malloc(#size(ElnaTreeStringLiteral));

	token_start := _elna_lexer_global_get_start();
	length := _string_length(token_start);
	_elna_lexer_skip_token();

	result^.kind := ElnaTreeKind.string_literal;
	result^.value := token_start;
	result^.length := length;
	result^.type_decoration := nil;

	return result
end;

proc _elna_tac_string_literal(string_literal_node: ^ElnaTreeStringLiteral, operand_type: Word, operand_value: Word, operand_length: Word);
var
	offset: Word;
	first_instruction: Word;
	next_instruction: Word;
begin
	offset := _add_string(string_literal_node^.value);

	first_instruction := _elna_tac_instruction_create(ElnaTacOperator.get_address);
	_elna_tac_instruction_set_operand(first_instruction, 1, ElnaTacOperand.pseudo, "$unary", 6);
	_elna_tac_instruction_set_operand(first_instruction, 2, ElnaTacOperand.symbol, "strings", 7);

	(* Add offset to the string block pointer. *)
	next_instruction := _elna_tac_instruction_create(ElnaTacOperator.add);
	_elna_tac_instruction_set_operand(next_instruction, 1, ElnaTacOperand.pseudo, "$unary", 6);
	_elna_tac_instruction_set_operand(next_instruction, 2, ElnaTacOperand.pseudo, "$unary", 6);
	_elna_tac_instruction_set_operand(next_instruction, 3, ElnaTacOperand.immediate, offset, 0);

	operand_type^ := ElnaTacOperand.pseudo;
	operand_value^ := "$unary";
	operand_length^ := 6;

	return elna_instruction_list_concatenate(first_instruction, next_instruction)
end;

proc elna_parser_trait_expression();
var
	result: ^ElnaTreeTraitExpression;
	token_kind: Word;
begin
	result := malloc(#size(ElnaTreeTraitExpression));
	result^.kind := ElnaTreeKind.trait_expression;

	result^.name := _elna_lexer_global_get_start();
	result^.length := _elna_lexer_global_get_end() - result^.name;

	_elna_lexer_skip_token();
	_elna_lexer_read_token(@token_kind);
	_elna_lexer_skip_token();

	result^.argument := elna_parser_type_expression();

	_elna_lexer_read_token(@token_kind);
	_elna_lexer_skip_token();

	return result
end;

proc elna_parser_simple_expression();
var
	current_character: Word;
	parser_node: Word;
	token_kind: Word;
begin
	parser_node := 0;
	_elna_lexer_read_token(@token_kind);

	if token_kind = ElnaLexerKind.character then
		parser_node := elna_parser_character_literal()
	elsif token_kind = ElnaLexerKind.integer then
		parser_node := elna_parser_integer_literal()
	elsif token_kind = ElnaLexerKind.string then
		parser_node := elna_parser_string_literal()
	elsif token_kind = ElnaLexerKind.boolean then
		parser_node := elna_parser_boolean_literal()
	elsif token_kind = ElnaLexerKind.null then
		parser_node := elna_parser_nil_literal()
	elsif token_kind = ElnaLexerKind.trait then
		parser_node := elna_parser_trait_expression()
	elsif token_kind = ElnaLexerKind.identifier then
		parser_node := elna_parser_variable_expression()
	end;
	return parser_node
end;

proc elna_parser_dereference_expression(simple_expression: Word);
var
	result: ^ElnaTreeDereferenceExpression;
begin
	result := malloc(#size(ElnaTreeDereferenceExpression));

	result^.kind := ElnaTreeKind.dereference_expression;
	result^.pointer := simple_expression;
	result^.type_decoration := nil;
	_elna_lexer_skip_token();

	return result
end;

proc elna_parser_designator();
var
	simple_expression: Word;
	token_kind: Word;
begin
	simple_expression := elna_parser_simple_expression();

	.elna_parser_designator_loop;
	_elna_lexer_read_token(@token_kind);

	if token_kind = ElnaLexerKind.hat then
		simple_expression := elna_parser_dereference_expression(simple_expression);
		goto elna_parser_designator_loop
	elsif token_kind = ElnaLexerKind.dot then
		simple_expression := elna_parser_field_access_expression(simple_expression);
		goto elna_parser_designator_loop
	elsif token_kind = ElnaLexerKind.left_paren then
		simple_expression := elna_parser_call(simple_expression);
		goto elna_parser_designator_loop
	end;
	return simple_expression
end;

proc elna_tac_trait_expression(trait_node: ^ElnaTreeTraitExpression, operand_type: Word, operand_value: Word, operand_length: Word);
var
	symbol: ^ElnaSymbolTypeInfo;
	info_type: ^ElnaType;
	parser_node: ^ElnaTreeNamedTypeExpression;
begin
	parser_node := trait_node^.argument;
	symbol := _symbol_table_lookup(@symbol_table_global, parser_node^.name, parser_node^.length);
	info_type := symbol^._type;

	operand_type^ := ElnaTacOperand.immediate;
	operand_value^ := info_type^.size;
	operand_length^ := 0;

	return nil
end;

proc elna_tac_simple_expression(parser_node: ^ElnaTreeNode, symbol_table: Word, operand_type: Word, operand_value: Word, operand_length: Word);
var
	instruction: Word;
begin
	if parser_node^.kind = ElnaTreeKind.character_literal then
		instruction := elna_tac_character_literal(parser_node, operand_type, operand_value, operand_length)
	elsif parser_node^.kind = ElnaTreeKind.string_literal then
		instruction := _elna_tac_string_literal(parser_node, operand_type, operand_value, operand_length)
	elsif parser_node^.kind = ElnaTreeKind.integer_literal then
		instruction := elna_tac_integer_literal(parser_node, operand_type, operand_value, operand_length)
	elsif parser_node^.kind = ElnaTreeKind.boolean_literal then
		instruction := elna_tac_boolean_literal(parser_node, operand_type, operand_value, operand_length)
	elsif parser_node^.kind = ElnaTreeKind.null then
		instruction := elna_tac_nil_literal(parser_node, operand_type, operand_value, operand_length)
	elsif parser_node^.kind = ElnaTreeKind.trait_expression then
		instruction := elna_tac_trait_expression(parser_node, operand_type, operand_value, operand_length)
	else
		instruction := elna_tac_variable_expression(parser_node, symbol_table, operand_type, operand_value, operand_length)
	end;
	return instruction
end;

proc elna_parser_unary_expression();
var
	token_kind: Word;
	result: ^ElnaTreeUnaryExpression;
	operand: Word;
	operator: Word;
begin
	_elna_lexer_read_token(@token_kind);
	operator := 0;

	if token_kind = ElnaLexerKind.at then
		operator := '@'
	elsif token_kind = ElnaLexerKind.minus then
		operator := '-'
	elsif token_kind = ElnaLexerKind.not then
		operator := '~'
	end;
	if operator <> 0 then
		_elna_lexer_skip_token()
	end;
	result := elna_parser_designator();

	if operator <> 0 then
		operand := result;
		result := malloc(#size(ElnaTreeUnaryExpression));

		result^.kind := ElnaTreeKind.unary_expression;
		result^.operand := operand;
		result^.operator := operator;
		result^.type_decoration := nil
	end;

	return result
end;

proc elna_tac_unary_expression(parser_node: ^ElnaTreeUnaryExpression, symbol_table: Word, operand_type: Word, operand_value: Word, operand_length: Word);
var
	token_kind: Word;
	operator: Word;
	operand: ^ElnaTreeExpression;
	is_address: Word;
	first_instruction: Word;
	instruction: Word;
begin
	instruction := nil;
	if parser_node^.kind = ElnaTreeKind.unary_expression then
		operator := parser_node^.operator;
		operand := parser_node^.operand
	else
		operator := 0;
		operand := parser_node
	end;
	first_instruction := elna_tac_designator(operand, symbol_table, @is_address, operand_type, operand_value, operand_length);

	if operator = '@' then
		instruction := _elna_tac_instruction_create(ElnaTacOperator.get_address);
		_elna_tac_instruction_set_operand(instruction, 1, ElnaTacOperand.pseudo, "$unary", 6);
		_elna_tac_instruction_set_operand(instruction, 2, operand_type^, operand_value^, operand_length^)
	elsif operator = '-' then
		instruction := _elna_tac_instruction_create(ElnaTacOperator.negate);
		_elna_tac_instruction_set_operand(instruction, 1, ElnaTacOperand.pseudo, "$unary", 6);
		_elna_tac_instruction_set_operand(instruction, 2, operand_type^, operand_value^, operand_length^)
	elsif operator = '~' then
		instruction := _elna_tac_instruction_create(ElnaTacOperator.complement);
		_elna_tac_instruction_set_operand(instruction, 1, ElnaTacOperand.pseudo, "$unary", 6);
		_elna_tac_instruction_set_operand(instruction, 2, operand_type^, operand_value^, operand_length^)
	elsif is_address then
		instruction := _elna_tac_instruction_create(ElnaTacOperator.load);
		_elna_tac_instruction_set_operand(instruction, 1, operand_type^, operand_value^, operand_length^);
		_elna_tac_instruction_set_operand(instruction, 2, ElnaTacOperand.pseudo, "$unary", 6)
	else
		instruction := _elna_tac_instruction_create(ElnaTacOperator.copy);
		_elna_tac_instruction_set_operand(instruction, 1, ElnaTacOperand.pseudo, "$unary", 6);
		_elna_tac_instruction_set_operand(instruction, 2, operand_type^, operand_value^, operand_length^)
	end;
	operand_type^ := ElnaTacOperand.pseudo;
	operand_value^ := "$unary";
	operand_length^ := 6;

	return elna_instruction_list_concatenate(first_instruction, instruction)
end;

proc elna_parser_binary_expression();
var
	lhs_node: Word;
	rhs_node: Word;
	token_kind: Word;
	result: ^ElnaTreeBinaryExpression;
begin
	lhs_node := elna_parser_unary_expression();
	rhs_node := 0;
	_elna_lexer_read_token(@token_kind);

	if token_kind = ElnaLexerKind.plus then
		_elna_lexer_skip_token();
		rhs_node := elna_parser_unary_expression()
	elsif token_kind = ElnaLexerKind.minus then
		_elna_lexer_skip_token();
		rhs_node := elna_parser_unary_expression()
	elsif token_kind = ElnaLexerKind.multiplication then
		_elna_lexer_skip_token();
		rhs_node := elna_parser_unary_expression()
	elsif token_kind = ElnaLexerKind.and then
		_elna_lexer_skip_token();
		rhs_node := elna_parser_unary_expression()
	elsif token_kind = ElnaLexerKind._or then
		_elna_lexer_skip_token();
		rhs_node := elna_parser_unary_expression()
	elsif token_kind = ElnaLexerKind._xor then
		_elna_lexer_skip_token();
		rhs_node := elna_parser_unary_expression()
	elsif token_kind = ElnaLexerKind.equals then
		_elna_lexer_skip_token();
		rhs_node := elna_parser_unary_expression()
	elsif token_kind = ElnaLexerKind.remainder then
		_elna_lexer_skip_token();
		rhs_node := elna_parser_unary_expression()
	elsif token_kind = ElnaLexerKind.division then
		_elna_lexer_skip_token();
		rhs_node := elna_parser_unary_expression()
	elsif token_kind = ElnaLexerKind.less_than then
		_elna_lexer_skip_token();
		rhs_node := elna_parser_unary_expression()
	elsif token_kind = ElnaLexerKind.greater_than then
		_elna_lexer_skip_token();
		rhs_node := elna_parser_unary_expression()
	elsif token_kind = ElnaLexerKind.less_equal then
		_elna_lexer_skip_token();
		rhs_node := elna_parser_unary_expression()
	elsif token_kind = ElnaLexerKind.not_equal then
		_elna_lexer_skip_token();
		rhs_node := elna_parser_unary_expression()
	elsif token_kind = ElnaLexerKind.greater_equal then
		_elna_lexer_skip_token();
		rhs_node := elna_parser_unary_expression()
	end;
	if rhs_node <> 0 then
		result := malloc(#size(ElnaTreeBinaryExpression));

		result^.kind := ElnaTreeKind.binary_expression;
		result^.lhs := lhs_node;
		result^.rhs := rhs_node;
		result^.operator := token_kind;
		result^.type_decoration := nil
	else
		result := lhs_node
	end;
	return result
end;

proc elna_tac_binary_expression(parser_node: ^ElnaTreeBinaryExpression, symbol_table: Word, operand_type: Word, operand_value: Word, operand_length: Word);
var
	first_instruction: Word;
	instruction: Word;
	current_instruction: Word;
	lhs_type: Word;
	lhs_value: Word;
	lhs_length: Word;
begin
	if parser_node^.kind <> ElnaTreeKind.binary_expression then
		first_instruction := elna_tac_unary_expression(parser_node, symbol_table, operand_type, operand_value, operand_length)
	else
		lhs_type := 0;
		lhs_value := 0;
		lhs_length := 0;
		first_instruction := elna_tac_unary_expression(parser_node^.lhs, symbol_table, @lhs_type, @lhs_value, @lhs_length);

		(* Save the value of the left expression on the stack. *)
		instruction := _elna_tac_instruction_create(ElnaTacOperator.copy);
		_elna_tac_instruction_set_operand(instruction, 1, ElnaTacOperand.pseudo, "$lhs", 4);
		_elna_tac_instruction_set_operand(instruction, 2, lhs_type, lhs_value, lhs_length);

		if first_instruction = 0 then
			first_instruction := instruction
		else
			elna_instruction_list_concatenate(first_instruction, instruction)
		end;
		current_instruction := instruction;

		lhs_type := 0;
		lhs_value := 0;
		lhs_length := 0;
		instruction := elna_tac_unary_expression(parser_node^.rhs, symbol_table, @lhs_type, @lhs_value, @lhs_length);
		current_instruction := elna_instruction_list_concatenate(current_instruction, instruction);

		if parser_node^.operator = ElnaLexerKind.plus then
			instruction := _elna_tac_instruction_create(ElnaTacOperator.add)
		elsif parser_node^.operator = ElnaLexerKind.minus then
			instruction := _elna_tac_instruction_create(ElnaTacOperator.subtract)
		elsif parser_node^.operator = ElnaLexerKind.multiplication then
			instruction := _elna_tac_instruction_create(ElnaTacOperator.multiply)
		elsif parser_node^.operator = ElnaLexerKind.and then
			instruction := _elna_tac_instruction_create(ElnaTacOperator.and)
		elsif parser_node^.operator = ElnaLexerKind._or then
			instruction := _elna_tac_instruction_create(ElnaTacOperator._or)
		elsif parser_node^.operator = ElnaLexerKind._xor then
			instruction := _elna_tac_instruction_create(ElnaTacOperator._xor)
		elsif parser_node^.operator = ElnaLexerKind.equals then
			instruction := _elna_tac_instruction_create(ElnaTacOperator.equal)
		elsif parser_node^.operator = ElnaLexerKind.remainder then
			instruction := _elna_tac_instruction_create(ElnaTacOperator.remainder)
		elsif parser_node^.operator = ElnaLexerKind.division then
			instruction := _elna_tac_instruction_create(ElnaTacOperator.divide)
		elsif parser_node^.operator = ElnaLexerKind.less_than then
			instruction := _elna_tac_instruction_create(ElnaTacOperator.less_than)
		elsif parser_node^.operator = ElnaLexerKind.greater_than then
			instruction := _elna_tac_instruction_create(ElnaTacOperator.greater_than)
		elsif parser_node^.operator = ElnaLexerKind.less_equal then
			instruction := _elna_tac_instruction_create(ElnaTacOperator.less_or_equal)
		elsif parser_node^.operator = ElnaLexerKind.greater_equal then
			instruction := _elna_tac_instruction_create(ElnaTacOperator.greater_or_equal)
		elsif parser_node^.operator = ElnaLexerKind.not_equal then
			instruction := _elna_tac_instruction_create(ElnaTacOperator.not_equal)
		end;
		_elna_tac_instruction_set_operand(instruction, 1, ElnaTacOperand.pseudo, "$binary", 7);
		_elna_tac_instruction_set_operand(instruction, 2, ElnaTacOperand.pseudo, "$lhs", 4);
		_elna_tac_instruction_set_operand(instruction, 3, lhs_type, lhs_value, lhs_length);

		operand_type^ := ElnaTacOperand.pseudo;
		operand_value^ := "$binary";
		operand_length^ := 7;

		elna_instruction_list_concatenate(current_instruction, instruction)
	end;
	return first_instruction
end;

(* 4 bytes node kind + 4 byte pointer to variable expression + 4 * 7 for arguments. *)
proc _call_size();
	return 44
end;

proc _call_get_name(this: Word);
begin
	this := this + 8;
	return this^
end;

proc _call_set_name(this: Word, value: Word);
begin
	this := this + 8;
	this^ := value
end;

proc _call_get_argument(this: Word, n: Word);
begin
	n := n * 4;
	this := this + 8;
	this := this + n;
	return this^
end;

proc _call_set_argument(this: Word, n: Word, value: Word);
begin
	n := n * 4;
	this := this + 8;
	this := this + n;
	this^ := value
end;

proc elna_parser_call(callee: Word);
var
	parsed_expression: Word;
	result: ^ElnaTreeStatement;
	argument_number: Word;
	token_kind: Word;
begin
	result := malloc(_call_size());
	result^.kind := ElnaTreeKind.call;
	result^.next := nil;

	argument_number := 1;
	_call_set_name(result, callee);

	_elna_lexer_read_token(@token_kind);
	_elna_lexer_skip_token();
	_elna_lexer_read_token(@token_kind);

	if token_kind = ElnaLexerKind.right_paren then
		_elna_lexer_skip_token();
		goto elna_parser_call_end
	end;

	.elna_parser_call_loop;
	parsed_expression := elna_parser_binary_expression();
	_call_set_argument(result, argument_number, parsed_expression);
	argument_number := argument_number + 1;
	_elna_lexer_read_token(@token_kind);
	_elna_lexer_skip_token();

	if token_kind = ElnaLexerKind.comma then
		goto elna_parser_call_loop
	end;

	.elna_parser_call_end;
	(* Set the trailing argument to nil. *)
	_call_set_argument(result, argument_number, nil);

	return result
end;

proc elna_tac_call(parsed_call: Word, symbol_table: Word, operand_type: Word, operand_value: Word, operand_length: Word);
var
	argument_count: Word;
	name_length: Word;
	name: Word;
	parsed_expression: ^ElnaTreeVariableExpression;
	instruction: Word;
	first_instruction: Word;
	current_instruction: Word;
	argument_type: Word;
	argument_value: Word;
	argument_length: Word;
	arguments_operand: Word;
	call_instruction: Word;
	name_buffer: Word;
begin
	parsed_expression := _call_get_name(parsed_call);
	name := parsed_expression^.name;
	name_length := parsed_expression^.length;
	argument_count := 0;
	first_instruction := 0;

	.elna_tac_call_count;
	parsed_expression := _call_get_argument(parsed_call, argument_count + 1);

	if parsed_expression <> nil ten
		argument_count := argument_count + 1;
		goto elna_tac_call_count
	end;
	arguments_operand := malloc(argument_count * 12);

	call_instruction := _elna_tac_instruction_create(ElnaTacOperator.proc_call);
	_elna_tac_instruction_set_operand(call_instruction, 1, ElnaTacOperand.symbol, name, name_length);
	_elna_tac_instruction_set_operand(call_instruction, 2, ElnaTacOperand.list, arguments_operand, argument_count);
	_elna_tac_instruction_set_operand(call_instruction, 3, ElnaTacOperand.pseudo, "$unary", 6);

	operand_type^ := ElnaTacOperand.pseudo;
	operand_value^ := "$unary";
	operand_length^ := 6;

	argument_count := 0;
	.elna_tac_call_loop;

	parsed_expression := _call_get_argument(parsed_call, argument_count + 1);
	if parsed_expression = 0 then
		goto elna_tac_call_finalize
	else
		argument_type := 0;
		argument_value := 0;
		argument_length := 0;
		instruction := elna_tac_binary_expression(parsed_expression, symbol_table, @argument_type, @argument_value, @argument_length);
		if first_instruction = 0 then
			first_instruction := instruction
		else
			elna_instruction_list_concatenate(current_instruction, instruction)
		end;
		if instruction <> 0 then
			current_instruction := instruction
		end;

		(* Save the argument on the stack. *)
		name_buffer := malloc(4);
		sprintf(name_buffer, "$ar%i\0", argument_count);
		instruction := _elna_tac_instruction_create(ElnaTacOperator.copy);
		_elna_tac_instruction_set_operand(instruction, 1, ElnaTacOperand.pseudo, name_buffer, 4);
		_elna_tac_instruction_set_operand(instruction, 2, argument_type, argument_value, argument_length);
		if first_instruction = 0 then
			first_instruction := instruction
		else
			elna_instruction_list_concatenate(current_instruction, instruction)
		end;
		current_instruction := instruction;

		arguments_operand^ := ElnaTacOperand.pseudo;
		arguments_operand := arguments_operand + 4;
		arguments_operand^ := name_buffer;
		arguments_operand := arguments_operand + 4;
		arguments_operand^ := 4;
		arguments_operand := arguments_operand + 4;

		argument_count := argument_count + 1;
		goto elna_tac_call_loop
	end;
	.elna_tac_call_finalize;

	if first_instruction = nil then
		first_instruction := call_instruction
	else
		elna_instruction_list_concatenate(current_instruction, call_instruction)
	end;
	return first_instruction
end;

proc elna_parser_goto_statement();
var
	token_kind: Word;
	result: ^ElnaTreeGotoStatement;
begin
	_elna_lexer_skip_token();
	_elna_lexer_read_token(@token_kind);

	result := malloc(#size(ElnaTreeGotoStatement));
	result^.kind := ElnaTreeKind.goto_statement;
	result^.next := nil;
	result^.label := _elna_lexer_global_get_start();
	result^.length := _elna_lexer_global_get_end() - result^.label;

	_elna_lexer_skip_token();

	return result
end;

proc elna_tac_goto_statement(parser_node: ^ElnaTreeGotoStatement);
var
	label_length1: Word;
	label_with_dot1: Word;
	instruction1: Word;
begin
	label_length1 := parser_node^.length + 1;
	label_with_dot1 := malloc(label_length1);

	_store_byte('.', label_with_dot1);
	memcpy(label_with_dot1 + 1, parser_node^.label, parser_node^.length);

	instruction1 := _elna_tac_instruction_create(ElnaTacOperator.jump);
	_elna_tac_instruction_set_operand(instruction1, 1, ElnaTacOperand.symbol, label_with_dot1, label_length1);
	return instruction1
end;

proc elna_parser_label_declaration();
var
	token_kind: Word;
	label_name: Word;
	label_length: Word;
	result: ^ElnaTreeGotoStatement;
begin
	_elna_lexer_skip_token();
	_elna_lexer_read_token(@token_kind);

	label_name := _elna_lexer_global_get_start();
	label_length := _elna_lexer_global_get_end() - label_name;
	_elna_lexer_skip_token();

	result := malloc(#size(ElnaTreeLabelDeclaration));

	result^.kind := ElnaTreeKind.label_declaration;
	result^.next := nil;
	result^.label := label_name;
	result^.length := label_length;

	return result
end;

proc elna_tac_label_declaration(parser_node: ^ElnaTreeLabelDeclaration);
	return elna_tac_label(parser_node^.label, parser_node^.length)
end;

proc elna_tac_enumeration_value(field_access_expression: ^ElnaTreeFieldAccessExpression, operand_type: Word, operand_value: Word, operand_length: Word);
var
	enumeration_type: ^ElnaTypeEnumeration;
	members: Word;
	members_length: Word;
	token_type: Word;
	symbol_info: ^ElnaSymbolTypeInfo;
	member_name: Word;
	member_length: Word;
	counter: Word;
	enumeration_type_name: ^ElnaTreeVariableExpression;
begin
	enumeration_type_name := field_access_expression^.aggregate;
	symbol_info := _symbol_table_lookup(@symbol_table_global, enumeration_type_name^.name, enumeration_type_name^.length);

	enumeration_type := symbol_info^._type;
	members := enumeration_type^.members;
	members_length := enumeration_type^.length;

	_elna_lexer_read_token(@token_type);
	counter := 1;

	.elna_tac_enumeration_value_members;
	if members_length > 0 then
		member_name := members^;
		member_length := members + 4;
		member_length := member_length^;

		if string_compare(field_access_expression^.field, field_access_expression^.length, member_name, member_length) = 0 then
			members_length := members_length - 1;
			members := members + 8;
			counter := counter + 1;
			goto elna_tac_enumeration_value_members
		end;
		(* Found. *)
		operand_type^ := ElnaTacOperand.immediate;
		operand_value^ := counter;
		operand_length^ := 0
	end;
	return nil
end;

proc elna_parser_field_access_expression(aggregate: Word);
var
	token_kind: Word;
	result: ^ElnaTreeFieldAccessExpression;
begin
	(* Skip dot. Read the enumeration value. *)
	_elna_lexer_skip_token();
	_elna_lexer_read_token(@token_kind);

	result := malloc(#size(ElnaTreeFieldAccessExpression));

	result^.kind := ElnaTreeKind.field_access_expression;
	result^.type_decoration := nil;
	result^.aggregate := aggregate;
	result^.field := _elna_lexer_global_get_start();
	result^.length := _elna_lexer_global_get_end() - result^.field;

	_elna_lexer_skip_token();

	return result
end;

proc elna_tac_designator(parser_node: ^ElnaTreeExpression, symbol_table: Word, is_address: Word, operand_type: Word, operand_value: Word, operand_length: Word);
var
	field_access_expression: ^ElnaTreeFieldAccessExpression;
	dereference_expression: ^ElnaTreeDereferenceExpression;
	field_type: ^ElnaType;
	first_instruction: Word;
	last_instruction: Word;
	designator_base: ^ElnaTreeExpression;
	aggregate_type: ^ElnaTypeRecord;
	field_count: Word;
	current_field: ^ElnaTypeField;
	field_offset: Word;
begin
	if parser_node^.kind = ElnaTreeKind.dereference_expression then
		dereference_expression := parser_node;
		first_instruction := elna_tac_designator(dereference_expression^.pointer, symbol_table, is_address, operand_type, operand_value, operand_length);
		is_address^ := 1
	elsif parser_node^.kind = ElnaTreeKind.field_access_expression then
		field_access_expression := parser_node;
		designator_base := field_access_expression^.aggregate;
		aggregate_type := designator_base^.type_decoration;

		if aggregate_type = nil then
			first_instruction := elna_tac_enumeration_value(field_access_expression, operand_type, operand_value, operand_length);
			is_address^ := 0
		else
			first_instruction := elna_tac_designator(designator_base, symbol_table, is_address, operand_type, operand_value, operand_length);

			field_count := aggregate_type^.length;
			current_field := aggregate_type^.members;
			field_offset := 0;

			.elna_tac_designator_field;

			if string_compare(field_access_expression^.field, field_access_expression^.length, current_field^.name, current_field^.length) = 0 then
				field_type := current_field^.field_type;
				field_count := field_count - 1;
				current_field := current_field + #size(ElnaTypeField);
				field_offset := field_offset + field_type^.size;
				goto elna_tac_designator_field
			end;
			last_instruction := _elna_tac_instruction_create(ElnaTacOperator.add);
			_elna_tac_instruction_set_operand(last_instruction, 1, ElnaTacOperand.pseudo, "$unary", 6);
			_elna_tac_instruction_set_operand(last_instruction, 2, ElnaTacOperand.immediate, field_offset, 0);
			_elna_tac_instruction_set_operand(last_instruction, 3, operand_type^, operand_value^, operand_length^);

			operand_type^ := ElnaTacOperand.pseudo;
			operand_value^ := "$unary";
			operand_length^ := 6;

			is_address^ := 1;
			first_instruction := elna_instruction_list_concatenate(first_instruction, last_instruction)
		end;
	elsif parser_node^.kind = ElnaTreeKind.call then
		first_instruction := elna_tac_call(parser_node, symbol_table, operand_type, operand_value, operand_length);
		is_address^ := 0
	else
		first_instruction := elna_tac_simple_expression(parser_node, symbol_table, operand_type, operand_value, operand_length);
		is_address^ := 0
	end;
	return first_instruction
end;

proc elna_parser_assign_statement(assignee: Word);
var
	result: ^ElnaTreeAssignStatement;
	token_kind: Word;
begin
	result := malloc(#size(ElnaTreeAssignStatement));

	result^.kind := ElnaTreeKind.assign_statement;
	result^.next := nil;
	result^.assignee := assignee;

	(* Skip the assignment sign (:=) with surrounding whitespaces. *)
	_elna_lexer_read_token(@token_kind);
	_elna_lexer_skip_token();

	result^.assignment := elna_parser_binary_expression();

	return result
end;

proc elna_tac_assign_statement(parser_tree: ^ElnaTreeAssignStatement, symbol_table: Word);
var
	is_address: Word;
	first_instruction: Word;
	instruction: Word;
	current_instruction: Word;
	operand_type: Word;
	operand_value: Word;
	operand_length: Word;
begin
	operand_type := 0;
	operand_value := 0;
	operand_length := 0;
	first_instruction := elna_tac_designator(parser_tree^.assignee, symbol_table, @is_address, @operand_type, @operand_value, @operand_length);

	if operand_type = ElnaTacOperand.pseudo then
		if is_address then
			(* Save the assignee address on the stack. *)
			current_instruction := _elna_tac_instruction_create(ElnaTacOperator.copy);
			_elna_tac_instruction_set_operand(current_instruction, 1, ElnaTacOperand.pseudo, "$assign", 7);
			_elna_tac_instruction_set_operand(current_instruction, 2, operand_type, operand_value, operand_length);
			first_instruction := elna_instruction_list_concatenate(first_instruction, current_instruction);

			(* Compile the assignment. *)
			operand_type := 0;
			operand_value := 0;
			operand_length := 0;
			instruction := elna_tac_binary_expression(parser_tree^.assignment, symbol_table, @operand_type, @operand_value, @operand_length);

			if instruction <> 0 then
				elna_instruction_list_concatenate(current_instruction, instruction);
				current_instruction := instruction
			end;

			instruction := _elna_tac_instruction_create(ElnaTacOperator.store);
			_elna_tac_instruction_set_operand(instruction, 1, operand_type, operand_value, operand_length);
			_elna_tac_instruction_set_operand(instruction, 2, ElnaTacOperand.pseudo, "$assign", 7);

			elna_instruction_list_concatenate(current_instruction, instruction)
		else
			current_instruction := _elna_tac_instruction_create(ElnaTacOperator.copy);
			_elna_tac_instruction_set_operand(current_instruction, 1, operand_type, operand_value, operand_length);

			operand_type := 0;
			operand_value := 0;
			operand_length := 0;
			instruction := elna_tac_binary_expression(parser_tree^.assignment, symbol_table, @operand_type, @operand_value, @operand_length);
			_elna_tac_instruction_set_operand(current_instruction, 2, operand_type, operand_value, operand_length);

			first_instruction := elna_instruction_list_concatenate(instruction, current_instruction)
		end
	else
		(* Save the assignee address on the stack. *)
		current_instruction := _elna_tac_instruction_create(ElnaTacOperator.get_address);
		_elna_tac_instruction_set_operand(current_instruction, 1, ElnaTacOperand.pseudo, "$assign", 7);
		_elna_tac_instruction_set_operand(current_instruction, 2, operand_type, operand_value, operand_length);
		first_instruction := elna_instruction_list_concatenate(first_instruction, current_instruction);

		(* Compile the assignment. *)
		operand_type := 0;
		operand_value := 0;
		operand_length := 0;
		instruction := elna_tac_binary_expression(parser_tree^.assignment, symbol_table, @operand_type, @operand_value, @operand_length);

		if instruction <> 0 then
			elna_instruction_list_concatenate(current_instruction, instruction);
			current_instruction := instruction
		end;

		instruction := _elna_tac_instruction_create(ElnaTacOperator.store);
		_elna_tac_instruction_set_operand(instruction, 1, operand_type, operand_value, operand_length);
		_elna_tac_instruction_set_operand(instruction, 2, ElnaTacOperand.pseudo, "$assign", 7);

		elna_instruction_list_concatenate(current_instruction, instruction)
	end;
	return first_instruction
end;

proc elna_parser_return_statement();
var
	token_kind: Word;
	returned: Word;
	label_length: Word;
	result: ^ElnaTreeReturnStatement;
begin
	(* Skip "return" keyword and whitespace after it. *)
	_elna_lexer_skip_token();
	_elna_lexer_read_token(@token_kind);

	returned := elna_parser_binary_expression();
	result := malloc(#size(ElnaTreeReturnStatement));

	result^.kind := ElnaTreeKind.return_statement;
	result^.next := nil;
	result^.returned := returned;

	return result
end;

proc elna_tac_return_statement(parser_node: ^ElnaTreeReturnStatement, symbol_table: Word);
var
	first_instruction: Word;
	instruction: Word;
	operand_type: Word;
	operand_value: Word;
	operand_length: Word;
begin
	operand_type := 0;
	operand_value := 0;
	operand_length := 0;
	first_instruction := elna_tac_binary_expression(parser_node^.returned, symbol_table, @operand_type, @operand_value, @operand_length);

	instruction := _elna_tac_instruction_create(ElnaTacOperator._return);
	_elna_tac_instruction_set_operand(instruction, 1, operand_type, operand_value, operand_length);

	return elna_instruction_list_concatenate(first_instruction, instruction)
end;

(**
 * Writes a label, .Ln, where n is a unique number.
 *
 * Parameters:
 * counter - Label counter.
 *)
proc _write_label(counter: Word, length: Word);
var
	first_byte: Word;
begin
	if length = 0 then
		_write_s(".L", 2);
		_write_i(counter)
	else
		first_byte := _load_byte(counter);
		if first_byte <> '.' then
			_write_c('.')
		end;
		_write_s(counter, length)
	end
end;

proc elna_parser_conditional_statements();
var
	token_kind: Word;
	result: ^ElnaTreeConditionalStatements;
begin
	result := malloc(#size(ElnaTreeConditionalStatements));

	(* Skip "if", "while" or "elsif". *)
	_elna_lexer_skip_token();
	result^.condition := elna_parser_binary_expression();

	(* Skip "then" or "do". *)
	_elna_lexer_read_token(@token_kind);
	_elna_lexer_skip_token();

	result^.statements := elna_parser_statements();
	result^.next := nil;

	return result
end;

proc elna_tac_conditional_statements(parser_node: ^ElnaTreeConditionalStatements, after_end_label: Word, symbol_table: Word);
var
	condition_label: Word;
	instruction: Word;
	current_instruction: Word;
	first_instruction: Word;
	operand_type: Word;
	operand_value: Word;
	operand_length: Word;
begin
	(* Compile condition. *)
	operand_type := 0;
	operand_value := 0;
	operand_length := 0;
	first_instruction := elna_tac_binary_expression(parser_node^.condition, symbol_table, @operand_type, @operand_value, @operand_length);

	(* condition_label is the label in front of the next elsif condition or end. *)
	condition_label := label_counter;
	label_counter := label_counter + 1;

	current_instruction := _elna_tac_instruction_create(ElnaTacOperator.jump_if_zero);
	_elna_tac_instruction_set_operand(current_instruction, 1, operand_type, operand_value, operand_length);
	_elna_tac_instruction_set_operand(current_instruction, 2, ElnaTacOperand.symbol, condition_label, 0);

	elna_instruction_list_concatenate(first_instruction, current_instruction);

	instruction := elna_tac_statements(parser_node^.statements, symbol_table);
	if instruction <> 0 then
		elna_instruction_list_concatenate(current_instruction, instruction);
		current_instruction := instruction
	end;

	instruction := _elna_tac_instruction_create(ElnaTacOperator.jump);
	_elna_tac_instruction_set_operand(instruction, 1, ElnaTacOperand.symbol, after_end_label, 0);
	elna_instruction_list_concatenate(current_instruction, instruction);

	current_instruction := elna_tac_label(condition_label, 0);
	elna_instruction_list_concatenate(instruction, current_instruction);

	return first_instruction
end;

proc elna_parser_if_statement();
var
	result: ^ElnaTreeIfStatement;
	token_kind: Word;
	previous_conditional: ^ElnaTreeConditionalStatements;
	next_conditional: ^ElnaTreeConditionalStatements;
begin
	result := malloc(#size(ElnaTreeIfStatement));

	result^.kind := ElnaTreeKind.if_statement;
	result^.next := nil;

	previous_conditional := elna_parser_conditional_statements();
	result^.conditionals := previous_conditional;

	.elna_parser_if_statement_loop;
	_elna_lexer_read_token(@token_kind);

	if token_kind = ElnaLexerKind._elsif then
		next_conditional := elna_parser_conditional_statements();
		previous_conditional^.next := next_conditional;
		previous_conditional = next_conditional;

		goto elna_parser_if_statement_loop
	elsif token_kind = ElnaLexerKind._else then
		_elna_lexer_skip_token();
		result^._else := elna_parser_statements()
	else
		result^._else := nil
	end;
	_elna_lexer_skip_token();

	return result
end;

proc elna_parser_statement();
var
	token_kind: Word;
	result : ^ElnaTreeNode;
begin
	result := nil;
	_elna_lexer_read_token(@token_kind);

	if token_kind = ElnaLexerKind._goto then
		result := elna_parser_goto_statement()
	elsif token_kind = ElnaLexerKind._if then
		result := elna_parser_if_statement()
	elsif token_kind = ElnaLexerKind._return then
		result := elna_parser_return_statement()
	elsif token_kind = ElnaLexerKind.dot then
		result := elna_parser_label_declaration()
	elsif token_kind = ElnaLexerKind.identifier then
		result := elna_parser_designator();

		if result^.kind <> ElnaTreeKind.call then
			result := elna_parser_assign_statement(result)
		end
	end;
	return result
end;

proc elna_parser_statements();
var
	token_kind: Word;
	previous_statement: ^ElnaTreeStatement;
	next_statement: ^ElnaTreeStatement;
	first_statement: ^ElnaTreeStatement;
begin
	_skip_empty_lines();

	first_statement := elna_parser_statement();
	previous_statement := first_statement;
	if previous_statement = 0 then
		goto elna_parser_statements_end
	end;

	.elna_parser_statement_loop;
	_elna_lexer_read_token(@token_kind);

	if token_kind = ElnaLexerKind.semicolon then
		_elna_lexer_skip_token();
		_skip_empty_lines();
		next_statement := elna_parser_statement();
		previous_statement^.next := next_statement;
		previous_statement := next_statement;

		if previous_statement <> 0 then
			goto elna_parser_statement_loop
		end
	end;
	.elna_parser_statements_end;
	_skip_empty_lines();

	return first_statement
end;

proc elna_tac_statements(parser_node: Word, symbol_table: Word);
var
	current_statement: ^ElnaTreeStatement;
	instruction: Word;
	first_instruction: Word;
	current_instruction: Word;
begin
	current_statement := parser_node;
	first_instruction := nil;

	.elna_tac_statements_loop;
	if current_statement <> nil then
		instruction := elna_tac_statement(current_statement, symbol_table);
		current_statement := current_statement^.next;
		if instruction = 0 then
			goto elna_tac_statements_loop
		end;
		if first_instruction = nil then
			first_instruction := instruction
		else
			elna_instruction_list_concatenate(current_instruction, instruction)
		end;
		current_instruction := instruction;
		goto elna_tac_statements_loop
	end;
	return first_instruction
end;

proc elna_tac_if_statement(parser_node: ^ElnaTreeIfStatement, symbol_table: Word);
var
	current_node: ^ElnaTreeConditionalStatements;
	after_end_label: Word;
	condition_label: Word;
	first_instruction: Word;
	instruction: Word;
	current_instruction: Word;
begin
	after_end_label := label_counter;
	label_counter := label_counter + 1;

	current_node := parser_node^.conditionals;
	first_instruction := elna_tac_conditional_statements(current_node, after_end_label, symbol_table);
	current_instruction := first_instruction;

	.elna_tac_if_statement_loop;
	current_node := current_node^.next;
	if current_node <> nil then
		instruction := elna_tac_conditional_statements(current_node, after_end_label, symbol_table);
		elna_instruction_list_concatenate(current_instruction, instruction);
		current_instruction := instruction;
		goto elna_tac_if_statement_loop
	end;
	current_node := parser_node^._else;

	if parser_node^._else <> nil then
		instruction := elna_tac_statements(parser_node^._else, symbol_table);
		if instruction <> 0 then
			elna_instruction_list_concatenate(current_instruction, instruction);
			current_instruction := instruction
		end
	end;
	instruction := elna_tac_label(after_end_label, 0);
	elna_instruction_list_concatenate(current_instruction, instruction);

	return first_instruction
end;

proc elna_tac_statement(parser_node: ^ElnaTreeNode, symbol_table: Word);
var
	instruction: Word;
	operand_type: Word;
	operand_value: Word;
	operand_length: Word;
begin
	if parser_node^.kind = ElnaTreeKind.goto_statement then
		instruction := elna_tac_goto_statement(parser_node)
	elsif parser_node^.kind = ElnaTreeKind.if_statement then
		instruction := elna_tac_if_statement(parser_node, symbol_table)
	elsif parser_node^.kind = ElnaTreeKind.return_statement then
		instruction := elna_tac_return_statement(parser_node, symbol_table)
	elsif parser_node^.kind = ElnaTreeKind.label_declaration then
		instruction := elna_tac_label_declaration(parser_node)
	elsif parser_node^.kind = ElnaTreeKind.call then
		instruction := elna_tac_call(parser_node, symbol_table, @operand_type, @operand_value, @operand_length)
	elsif parser_node^.kind = ElnaTreeKind.assign_statement then
		instruction := elna_tac_assign_statement(parser_node, symbol_table)
	else
		instruction := nil
	end;
	return instruction
end;

(**
 * Writes a regster name to the standard output.
 *
 * Parameters:
 * register_character - Register character.
 * register_number - Register number.
 *)
proc _write_register(register_character: Word, register_number: Word);
begin
	_write_c(register_character);
	_write_c(register_number + '0')
end;

proc elna_parser_record_type_expression();
var
	entry: Word;
	member_count: Word;
	memory_start: Word;
	field_name: Word;
	field_length: Word;
	field_type: Word;
	token_kind: Word;
	result: ^ElnaTreeEnumerationTypeExpression;
	previous_entry: Word;
begin
	_elna_lexer_skip_token();
	member_count := 0;
	memory_start := 0;

	_elna_lexer_read_token(@token_kind);
	if token_kind = ElnaLexerKind._end then
		goto elna_parser_record_type_expression_end
	end;
	.elna_parser_record_type_expression_loop;
	entry := malloc(16);
	member_count := member_count + 1;

	field_name := _elna_lexer_global_get_start();
	field_length := _elna_lexer_global_get_end() - field_name;

	entry^ := field_name;
	entry := entry + 4;

	entry^ := field_length;
	entry := entry + 4;

	(* Skip the identifier. *)
	_elna_lexer_skip_token();
	_elna_lexer_read_token(@token_kind);
	_elna_lexer_skip_token();

	field_type := elna_parser_type_expression();

	entry^ := field_type;
	entry := entry + 4;

	entry^ := 0;
	if memory_start = 0 then
		memory_start := entry - 12
	else
		previous_entry^ := entry - 12
	end;
	previous_entry := entry;

	_elna_lexer_read_token(@token_kind);
	if token_kind = ElnaLexerKind.semicolon then
		_elna_lexer_skip_token();
		_elna_lexer_read_token(@token_kind);
		goto elna_parser_record_type_expression_loop
	end;

	.elna_parser_record_type_expression_end;
	_elna_lexer_skip_token();

	result := malloc(#size(ElnaTreeEnumerationTypeExpression));

	result^.kind := ElnaTreeKind.record_type_expression;
	result^.members := memory_start;
	result^.length := member_count;

	return result
end;

proc elna_parser_enumeration_type_expression();
var
	token_kind: Word;
	enumeration_name: Word;
	name_length: Word;
	memory_start: Word;
	member_count: Word;
	result: ^ElnaTreeEnumerationTypeExpression;
	entry: Word;
	previous_entry: Word;
begin
	_elna_lexer_skip_token();
	memory_start := 0;
	member_count := 0;

	_elna_lexer_read_token(@token_kind);
	if token_kind = ElnaLexerKind.right_paren then
		goto elna_parser_enumeration_type_expression_end
	end;
	.elna_parser_enumeration_type_expression_loop;
	entry := malloc(12);
	member_count := member_count + 1;

	enumeration_name := _elna_lexer_global_get_start();
	name_length := _elna_lexer_global_get_end() - enumeration_name;

	entry^ := enumeration_name;
	entry := entry + 4;

	entry^ := name_length;
	entry := entry + 4;

	entry^ := 0;
	if memory_start = 0 then
		memory_start := entry - 8
	else
		previous_entry^ := entry - 8
	end;
	previous_entry := entry;

	(* Skip the identifier. *)
	_elna_lexer_skip_token();

	_elna_lexer_read_token(@token_kind);
	if token_kind = ElnaLexerKind.comma then
		_elna_lexer_skip_token();
		_elna_lexer_read_token(@token_kind);
		goto elna_parser_enumeration_type_expression_loop
	end;

	.elna_parser_enumeration_type_expression_end;
	_elna_lexer_skip_token();

	result := malloc(#size(ElnaTreeEnumerationTypeExpression));

	result^.kind := ElnaTreeKind.enumeration_type_expression;
	result^.members := memory_start;
	result^.length := member_count;

	return result
end;

(**
 * Reads and creates enumeration type representation.
 *
 * record
 *   type_kind: Word;
 *   size: Word;
 *   members: StringArray;
 *   length: Word
 * end;
 *
 * Returns enumeration type description.
 *)
proc elna_name_enumeration_type_expression(parser_node: ^ElnaTreeEnumerationTypeExpression);
var
	result: ^ElnaTypeEnumeration;
	memory_start: Word;
	member_count: Word;
	member_array_start: Word;
	member_array_current: Word;
begin
	result := malloc(#size(ElnaTypeEnumeration));

	memory_start := parser_node^.members;
	member_count := parser_node^.length;

	(* Copy the list of enumeration members into an array of strings. *)
	member_array_start := malloc(member_count * 8);
	member_array_current := member_array_start;

	.elna_name_type_enumeration_loop;
	if member_count > 0 then
		member_array_current^ := memory_start^;
		member_array_current := member_array_current + 4;
		memory_start := memory_start + 4;

		member_array_current^ := memory_start^;
		member_array_current := member_array_current + 4;
		memory_start := memory_start + 4;

		memory_start := memory_start^;
		member_count := member_count - 1;
		goto elna_name_type_enumeration_loop
	end;
	member_count := parser_node^.length;

	result^.kind := ElnaTypeKind.enumeration;
	result^.size := 4;
	result^.members := member_array_start;
	result^.length := member_count;

	return result
end;

proc elna_name_pointer_type_expression(parser_node: ^ElnaTreePointerTypeExpression);
var
	result: ^ElnaTypePointer;
begin
	result := malloc(#size(ElnaTypePointer));

	result^.kind := ElnaTypeKind.pointer;
	result^.size := 4;
	result^.base := elna_name_type_expression(parser_node^.base);

	return result
end;

proc elna_name_array_type_expression(parser_node: ^ElnaTreeArrayTypeExpression);
var
	base: ^ElnaType;
	result: ^ElnaTypeArray;
	length: ^ElnaTreeIntegerLiteral;
begin
	result := malloc(#size(ElnaTypeArray));
	base := elna_name_type_expression(parser_node^.base);

	(* TODO: Expected to be an integer literal for now. *)
	length := parser_node^.length;

	result^.kind := ElnaTypeKind.array;
	(* Array size in bytes. *)
	result^.size := base^.size * length^.value;
	result^.base := base;
	result^.length := length^.value;

	return result
end;

proc elna_name_record_type_expression(parser_node: ^ElnaTreeRecordTypeExpression);
var
	result: ^ElnaTypeRecord;
	memory_start: Word;
	member_count: Word;
	member_array_start: Word;
	member_array_current: ^ElnaTypeField;
	field_type: ^ElnaType;
begin
	result := malloc(#size(ElnaTypeRecord));
	result^.size := 0;

	memory_start := parser_node^.members;
	member_count := parser_node^.length;

	member_array_start := malloc(member_count * #size(ElnaTypeField));
	member_array_current := member_array_start;

	.elna_name_type_record_loop;
	if member_count > 0 then
		member_array_current^.name := memory_start^;
		memory_start := memory_start + 4;

		member_array_current^.length := memory_start^;
		memory_start := memory_start + 4;

		field_type := elna_name_type_expression(memory_start^);
		result^.size := result^.size + field_type^.size;
		member_array_current^.field_type := field_type;

		member_array_current := member_array_current + #size(ElnaTypeField);
		memory_start := memory_start + 4;

		memory_start := memory_start^;
		member_count := member_count - 1;
		goto elna_name_type_record_loop
	end;

	result^.kind := ElnaTypeKind._record;
	result^.members := member_array_start;
	result^.length := parser_node^.length;

	return result
end;

proc elna_parser_named_type_expression();
var
	result: ^ElnaTreeNamedTypeExpression;
begin
	result := malloc(#size(ElnaTreeNamedTypeExpression));

	result^.kind := ElnaTreeKind.named_type_expression;
	result^.name := _elna_lexer_global_get_start();
	result^.length := _elna_lexer_global_get_end() - result^.name;
	_elna_lexer_skip_token();

	return result
end;

proc elna_parser_pointer_type_expression();
var
	result: ^ElnaTreePointerTypeExpression;
begin
	_elna_lexer_skip_token();

	result := malloc(#size(ElnaTreePointerTypeExpression));
	result^.kind := ElnaTreeKind.pointer_type_expression;
	result^.base := elna_parser_type_expression();

	return result
end;

proc elna_parser_array_type_expression();
var
	result: ^ElnaTreeArrayTypeExpression;
	token_kind: Word;
begin
	_elna_lexer_skip_token();

	result := malloc(#size(ElnaTreeArrayTypeExpression));
	result^.kind := ElnaTreeKind.array_type_expression;
	result^.length := elna_parser_binary_expression();

	(* Read and skip square bracket. *)
	_elna_lexer_read_token(@token_kind);
	_elna_lexer_skip_token();

	result^.base := elna_parser_type_expression();

	return result
end;

proc elna_parser_type_expression();
var
	token_kind: Word;
	result: Word;
begin
	result := nil;
	_elna_lexer_read_token(@token_kind);

	if token_kind = ElnaLexerKind.identifier then
		result := elna_parser_named_type_expression()
	elsif token_kind = ElnaLexerKind.left_paren then
		result := elna_parser_enumeration_type_expression()
	elsif token_kind = ElnaLexerKind._record then
		result := elna_parser_record_type_expression()
	elsif token_kind = ElnaLexerKind.hat then
		result := elna_parser_pointer_type_expression()
	elsif token_kind = ElnaLexerKind.left_square then
		result := elna_parser_array_type_expression()
	end;
	return result
end;

proc elna_name_type_expression(parser_node: ^ElnaTreeNode);
var
	named_type_expression: ^ElnaTreeNamedTypeExpression;
	type_symbol: ^ElnaSymbolTypeInfo;
	result: Word;
begin
	if parser_node^.kind = ElnaTreeKind.named_type_expression then
		named_type_expression := parser_node;

		type_symbol := _symbol_table_lookup(@symbol_table_global, named_type_expression^.name, named_type_expression^.length);
		result := type_symbol^._type
	elsif parser_node^.kind = ElnaTreeKind.enumeration_type_expression then
		result := elna_name_enumeration_type_expression(parser_node)
	elsif parser_node^.kind = ElnaTreeKind.record_type_expression then
		result := elna_name_record_type_expression(parser_node)
	elsif parser_node^.kind = ElnaTreeKind.pointer_type_expression then
		result := elna_name_pointer_type_expression(parser_node)
	elsif parser_node^.kind = ElnaTreeKind.array_type_expression then
		result := elna_name_array_type_expression(parser_node)
	end;

	return result
end;

proc _type_info_create(type_representation: Word);
var
	result: ^ElnaSymbolTypeInfo;
begin
	result := malloc(#size(ElnaSymbolTypeInfo));
	result^.kind := ElnaSymbolInfoKind.type_info;
	result^._type := type_representation;

	return result
end;

(**
 * Parameters:
 * temporary_index - Local variable index.
 * temporary_type - Local variable type.
 *)
proc _temporary_info_create(temporary_index: Word, temporary_type: Word);
var
	result: ^ElnaSymbolTemporaryInfo;
begin
	result := malloc(#size(ElnaSymbolTemporaryInfo));
	result^.kind := ElnaSymbolInfoKind.temporary_info;

	(* Calculate the stack offset: 4 * variable_counter. *)
	result^.offset := temporary_index * 4;
	result^.variable_type := temporary_type;

	return result
end;

(**
 * Parameters:
 * symbol_table - Local symbol table.
 *)
proc _procedure_info_create(symbol_table: Word);
var
	result: ^ElnaSymbolProcedureInfo;
begin
	result := malloc(#size(ElnaSymbolProcedureInfo));
	result^.kind := ElnaSymbolInfoKind.procedure_info;
	result^.symbol_table := symbol_table;

	return result
end;

(**
 * Parameters:
 * variable_index - Variable index.
 *)
proc elna_name_procedure_temporary(parser_node: ^ElnaTreeVariableDeclaration, variable_index: Word, symbol_table: Word);
var
	info: Word;
	variable_type1: Word;
begin
	variable_type1 := elna_name_type_expression(parser_node^._type);

	info := _temporary_info_create(variable_index, variable_type1);
	_symbol_table_enter(symbol_table, parser_node^.name, parser_node^.length, info)
end;

proc elna_name_procedure_temporaries(parser_node: ^ElnaTreeVariableDeclaration, symbol_table: Word);
var
	temporary_counter: Word;
begin
	temporary_counter := 0;

	.elna_name_procedure_temporaries_loop;
	if parser_node <> nil then
		elna_name_procedure_temporary(parser_node, temporary_counter, symbol_table);

		temporary_counter := temporary_counter + 1;
		parser_node := parser_node^.next;
		goto elna_name_procedure_temporaries_loop
	end
end;

proc elna_parser_procedure_declaration();
var
	next_declaration: ^ElnaTreeDeclaration;
	current_declaration: ^ElnaTreeDeclaration;
	token_kind: Word;
	result: ^ElnaTreeProcedureDeclaration;
	parameter_head: ^ElnaTreeDeclaration;
begin
	result := malloc(#size(ElnaTreeProcedureDeclaration));

	result^.kind := ElnaTreeKind.procedure_declaration;
	result^.next := nil;

	(* Skip "proc ". *)
	_elna_lexer_skip_token();

	_elna_lexer_read_token(@token_kind);

	result^.name := _elna_lexer_global_get_start();
	result^.length := _elna_lexer_global_get_end() - result^.name;
	(* Skip procedure name. *)
	_elna_lexer_skip_token();

	(* Skip open paren. *)
	_elna_lexer_read_token(@token_kind);
	_elna_lexer_skip_token();
	parameter_head := nil;

	.elna_parser_procedure_declaration_parameter;
	_elna_lexer_read_token(@token_kind);

	if token_kind <> ElnaLexerKind.right_paren then
		next_declaration := elna_parser_variable_declaration();
		if parameter_head = nil then
			parameter_head := next_declaration
		else
			current_declaration^.next := next_declaration
		end;
		current_declaration := next_declaration;

		_elna_lexer_read_token(@token_kind);

		if token_kind = ElnaLexerKind.comma then
			_elna_lexer_skip_token();
			goto elna_parser_procedure_declaration_parameter
		end
	end;
	(* Skip close paren. *)
	_elna_lexer_skip_token();
	result^.parameters := parameter_head;

	(* Skip semicolon and newline. *)
	_elna_lexer_read_token(@token_kind);
	_elna_lexer_skip_token();

	parameter_head := elna_parser_var_part();
	result^.temporaries := parameter_head;

	(* Skip semicolon, "begin" and newline. *)
	_elna_lexer_read_token(@token_kind);
	if token_kind = ElnaLexerKind._begin then
		_elna_lexer_skip_token();
		parameter_head := elna_parser_statements()
	elsif token_kind = ElnaLexerKind._return then
		parameter_head := elna_parser_return_statement()
	end;
	result^.body := parameter_head;

	(* Skip the "end" keyword. *)
	_elna_lexer_read_token(@token_kind);
	_elna_lexer_skip_token();

	return result
end;

proc elna_tac_parameters(ast_list: ^ElnaTreeDeclaration, parameter_count: ^Word);
var
	ast_parameter: ^ElnaTreeDeclaration;
	parameter_index: Word;
	current_parameter: Word;
	parameter_list: Word;
begin
	ast_parameter := ast_list;
	parameter_count^ := 0;

	.elna_tac_parameters_count;
	if ast_parameter <> nil then
		ast_parameter := ast_parameter^.next;
		parameter_count^ := parameter_count^ + 1;

		goto elna_tac_parameters_count
	end;
	(* The parameters are saved as an array of name pointer + name length. *)
	parameter_list := malloc(parameter_count^ * 8);
	current_parameter := parameter_list;

	ast_parameter := ast_list;
	parameter_index := 0;

	.elna_tac_parameters_loop;
	if parameter_index < parameter_count^ then
		current_parameter^ := ast_parameter^.name;
		current_parameter := current_parameter + 4;
		current_parameter^ := ast_parameter^.length;
		current_parameter := current_parameter + 4;

		parameter_index := parameter_index + 1;
		ast_parameter := ast_parameter^.next;
		goto elna_tac_parameters_loop
	end;

	return parameter_list
end;

proc elna_rtl_global_declaration(tac_declaration: ^ElnaInstructionDeclaration);
var
	result: ElnaInstructionDeclaration;
begin
	result := malloc(#size(ElnaInstructionDeclaration));

	result^.next := 0;
	result^.name := tac_declaration^.name;
	result^.length := tac_declaration^.length;
	result^.body := tac_declaration^.body;

	return result
end;

proc elna_rtl_parameters(parameters: Word, count: Word);
var
	result: Word;
	current_instruction: Word;
	last_instruction: Word;
	parameter_index: Word;
	parameter_name: Word;
	name_length: Word;
begin
	result := nil;
	parameter_index := 0;

	.elna_rtl_parameters_loop;
	if parameter_index < count then
		parameter_name := parameters^;
		parameters := parameters + 4;
		name_length := parameters^;
		parameters := parameters + 4;

		current_instruction := elna_rtl_instruction_create(ElnaRtlOperator.move);
		elna_rtl_instruction_set_operand(current_instruction, 1, ElnaRtlOperand.pseudo, parameter_name, name_length);
		elna_rtl_instruction_set_operand(current_instruction, 2, ElnaRtlOperand.register, 11 + parameter_index, 0);

		if result = nil then
			result := current_instruction
		else
			elna_instruction_list_concatenate(last_instruction, current_instruction)
		end;
		last_instruction := current_instruction;

		parameter_index := parameter_index + 1;
		goto elna_rtl_parameters_loop
	end;

	return result
end;

proc elna_rtl_procedure_declaration(tac_declaration: ^ElnaInstructionDeclaration);
var
	result: ^ElnaInstructionDeclaration;
	body: ^ElnaInstructionList;
	parameters: ^ElnaInstructionList;
begin
	result := malloc(#size(ElnaInstructionDeclaration));

	result^.next := nil;
	result^.name := tac_declaration^.name;
	result^.length := tac_declaration^.length;
	result^.stack := tac_declaration^.stack;

	parameters = elna_rtl_parameters(tac_declaration^.parameters, tac_declaration^.count);
	body := elna_rtl_instructions(tac_declaration^.body);
	result^.body := elna_instruction_list_concatenate(parameters, body);

	return result
end;

proc elna_tac_procedure_declaration(parser_node: ElnaTreeProcedureDeclaration);
var
	symbol_info: ^ElnaSymbolProcedureInfo;
	result: ^ElnaInstructionDeclaration;
	parameter_count: Word;
begin
	result := malloc(#size(ElnaInstructionDeclaration));

	result^.next := nil;
	result^.stack := 1;

	result^.name := parser_node^.name;
	result^.length := parser_node^.length;

	symbol_info := _symbol_table_lookup(@symbol_table_global, parser_node^.name, parser_node^.length);

	result^.parameters := elna_tac_parameters(parser_node^.parameters, @parameter_count);
	result^.count := parameter_count;
	result^.body := elna_tac_statements(parser_node^.body, symbol_info^.symbol_table);

	return result
end;

proc elna_parser_procedures();
var
	parser_node: ^ElnaTreeDeclaration;
	result: ^ElnaTreeDeclaration;
	current_declaration: ^ElnaTreeDeclaration;
	token_kind: Word;
begin
	result := nil;

	.elna_parser_procedures_loop;
	_skip_empty_lines();
	_elna_lexer_read_token(@token_kind);

	if token_kind = ElnaLexerKind._proc then
		parser_node := elna_parser_procedure_declaration();
		if result = 0 then
			result := parser_node
		else
			current_declaration^.next := parser_node
		end;
		current_declaration := parser_node;

		(* Skip semicolon. *)
		_elna_lexer_read_token(@token_kind);
		_elna_lexer_skip_token();

		goto elna_parser_procedures_loop
	end;
	return result
end;

proc elna_rtl_globals(tac_procedure: ^ElnaInstructionList);
var
	current_copy: ^ElnaInstructionList;
	next_copy: Word;
	first_copy: ^ElnaInstructionList;
begin
	if tac_procedure <> 0 then
		first_copy := elna_rtl_global_declaration(tac_procedure);
		tac_procedure := tac_procedure^.next
	else
		first_copy := nil
	end;
	current_copy := first_copy;

	.elna_rtl_globals_start;

	if tac_procedure <> 0 then
		next_copy := elna_rtl_global_declaration(tac_procedure);

		tac_procedure := tac_procedure^.next;
		current_copy^.next := next_copy;
		current_copy := next_copy;
		goto elna_rtl_globals_start
	end;

	return first_copy
end;

proc elna_rtl_procedures(tac_procedure: ^ElnaInstructionList);
var
	current_copy: ^ElnaInstructionList;
	next_copy: Word;
	first_copy: ^ElnaInstructionList;
begin
	if tac_procedure <> nil then
		first_copy := elna_rtl_procedure_declaration(tac_procedure);
		tac_procedure := tac_procedure^.next
	else
		first_copy := nil;
	end;
	current_copy := first_copy;

	.elna_rtl_procedures_start;

	if tac_procedure <> nil then
		next_copy := elna_rtl_procedure_declaration(tac_procedure);

		tac_procedure := tac_procedure^.next;
		current_copy^.next := next_copy;
		current_copy := next_copy;
		goto elna_rtl_procedures_start
	end;

	return first_copy
end;

proc elna_tac_procedures(parser_node: ^ElnaTreeDeclaration);
var
	result: Word;
	current_procedure: ^ElnaInstructionList;
	first_procedure: Word;
begin
	first_procedure := nil;

	.elna_tac_procedures_loop;
	if parser_node = 0 then
		goto elna_tac_procedures_end
	end;
	result := elna_tac_procedure_declaration(parser_node);
	if first_procedure = nil then
		first_procedure := result
	else
		current_procedure^.next := result
	end;
	current_procedure := result;

	parser_node := parser_node^.next;
	goto elna_tac_procedures_loop;

	.elna_tac_procedures_end;
	return first_procedure
end;

(**
 * Skips comments.
 *)
proc _skip_empty_lines();
var
	token_kind: Word;
begin
	.skip_empty_lines_rerun;

	_elna_lexer_read_token(@token_kind);

	if token_kind = ElnaLexerKind.comment then
		_elna_lexer_skip_token();
		goto skip_empty_lines_rerun
	end
end;

proc elna_parser_type_declaration();
var
	token_kind: Word;
	type_name: Word;
	name_length: Word;
	result: ^ElnaTreeTypeDeclaration;
begin
	_elna_lexer_read_token(@token_kind);
	type_name := _elna_lexer_global_get_start();
	name_length := _elna_lexer_global_get_end() - type_name;

	_elna_lexer_skip_token();
	_elna_lexer_read_token(@token_kind);
	_elna_lexer_skip_token();

	result := malloc(#size(ElnaTreeTypeDeclaration));

	result^.kind := ElnaTreeKind.type_declaration;
	result^.next := nil;
	result^.name := type_name;
	result^.length := name_length;
	result^._type := elna_parser_type_expression();

	_elna_lexer_read_token(@token_kind);
	_elna_lexer_skip_token();

	return result
end;

proc elna_name_type_declaration(parser_node: ^ElnaTreeTypeDeclaration);
var
	type_name: Word;
	name_length: Word;
	type_info: Word;
begin
	type_name := parser_node^.name;
	name_length := parser_node^.length;

	parser_node := parser_node^._type;
	type_info := elna_name_type_expression(parser_node);
	type_info := _type_info_create(type_info);

	_symbol_table_enter(@symbol_table_global, type_name, name_length, type_info)
end;

proc elna_type_type_declaration(parser_node: Word);
begin
end;

proc elna_parser_type_part();
var
	token_kind: Word;
	parser_node: ^ElnaTreeDeclaration;
	result: ^ElnaTreeDeclaration;
	current_declaration: ^ElnaTreeDeclaration;
begin
	result := nil;
	_skip_empty_lines();
	_elna_lexer_read_token(@token_kind);

	if token_kind <> ElnaLexerKind._type then
		goto elna_parser_type_part_end
	end;
	_elna_lexer_skip_token();

	.elna_parser_type_part_loop;
	_skip_empty_lines();

	_elna_lexer_read_token(@token_kind);
	if token_kind = ElnaLexerKind.identifier then
		parser_node := elna_parser_type_declaration();

		if result = nil then
			result := parser_node
		else
			current_declaration^.next := parser_node
		end;
		current_declaration := parser_node;
		goto elna_parser_type_part_loop
	end;

	.elna_parser_type_part_end;
	return result
end;

proc elna_parser_variable_declaration();
var
	token_kind: Word;
	name: Word;
	name_length: Word;
	variable_type1: Word;
	result: ^ElnaTreeVariableDeclaration;
begin
	_elna_lexer_read_token(@token_kind);

	name := _elna_lexer_global_get_start();
	name_length := _elna_lexer_global_get_end() - name;

	(* Skip the variable name and colon with the type. *)
	_elna_lexer_skip_token();
	_elna_lexer_read_token(@token_kind);
	_elna_lexer_skip_token();

	variable_type1 := elna_parser_type_expression();
	result := malloc(#size(ElnaTreeVariableDeclaration));

	result^.kind := ElnaTreeKind.variable_declaration;
	result^.next := nil;
	result^.name := name;
	result^.length := name_length;
	result^._type := variable_type1;

	return result
end;

proc elna_tac_variable_declaration(parser_tree: ^ElnaTreeVariableDeclaration);
var
	name: Word;
	name_length: Word;
	variable_type: ^ElnaTreeNamedTypeExpression;
	result: ^ElnaInstructionDeclaration;
begin
	result := malloc(#size(ElnaInstructionDeclaration));

	result^.next := nil;

	name := parser_tree^.name;
	name_length := parser_tree^.length;
	variable_type := parser_tree^._type;

	result^.name := name;
	result^.length := name_length;

	name := variable_type^.name;
	name_length := variable_type^.length;

	if string_compare("Array", 5, name, name_length) then
		(* Else we assume this is a zeroed 4096 bytes big array. *)
		result^.body := 4096
	else
		result^.body := 4
	end;
	return result
end;

proc elna_parser_var_part();
var
	result: Word;
	token_kind: Word;
	variable_node: Word;
	current_declaration: ^ElnaTreeDeclaration;
begin
	result := 0;
	_elna_lexer_read_token(@token_kind);

	if token_kind <> ElnaLexerKind._var then
		goto elna_parser_var_part_end
	end;
	(* Skip "var". *)
	_elna_lexer_skip_token();

	.elna_parser_var_part_loop;
	_skip_empty_lines();
	_elna_lexer_read_token(@token_kind);

	if token_kind = ElnaLexerKind.identifier then
		variable_node := elna_parser_variable_declaration();

		(* Skip semicolon. *)
		_elna_lexer_read_token(@token_kind);
		_elna_lexer_skip_token();

		if result = 0 then
			result := variable_node
		else
			current_declaration^.next := variable_node
		end;
		current_declaration := variable_node;
		goto elna_parser_var_part_loop
	end;

	.elna_parser_var_part_end;
	return result
end;

proc elna_tac_var_part(parser_node: ^ElnaTreeDeclaration);
var
	node: Word;
	current_variable: ^ElnaInstructionList;
	first_variable: Word;
begin
	first_variable := 0;
	if parser_node = 0 then
		goto elna_tac_var_part_end
	end;

	.elna_tac_var_part_loop;
	node := elna_tac_variable_declaration(parser_node);
	if first_variable = 0 then
		first_variable := node
	else
		current_variable^.next := node
	end;
	current_variable := node;

	parser_node := parser_node^.next;
	if parser_node <> 0 then
		goto elna_tac_var_part_loop
	end;

	.elna_tac_var_part_end;
	return first_variable
end;

proc elna_parser_module_declaration(error_list: ^ElnaErrorList);
var
	parser_node: Word;
	result: ^ElnaTreeModuleDeclaration;
	token_kind: Word;
	parser_error: ^ElnaError;
begin
	result := malloc(#size(ElnaTreeModuleDeclaration));
	result^.kind := ElnaTreeKind.module_declaration;

	(* Skip "program;". *)
	_skip_empty_lines();
	_elna_lexer_read_token(@token_kind);

	if token_kind <> ElnaLexerKind._program then
 		parser_error := malloc(#size(ElnaError));
		parser_error^.next := nil;

		error_list^.first := parser_error;
		error_list^.last := parser_error
	else
		_elna_lexer_skip_token();
		_elna_lexer_read_token(@token_kind);
		_elna_lexer_skip_token();

		result^.types := elna_parser_type_part();
		result^.globals := elna_parser_var_part();
		result^.procedures := elna_parser_procedures()
	end;
	return result
end;

(**
 * Process the source code and print the generated code.
 *)
proc elna_tac_module_declaration(parser_node: ^ElnaTreeModuleDeclaration);
var
	data_part: Word;
	code_part: Word;
begin
	data_part := elna_tac_var_part(parser_node^.globals);
	code_part := elna_tac_procedures(parser_node^.procedures);

	return elna_instruction_module_create(data_part, code_part)
end;

proc elna_name_procedure_declaration(parser_node: ^ElnaTreeProcedureDeclaration);
var
	new_symbol_table: Word;
	symbol_info: Word;
begin
	new_symbol_table := _symbol_table_create();
	symbol_info := _procedure_info_create(new_symbol_table);

	elna_name_procedure_temporaries(parser_node^.parameters, new_symbol_table);
	elna_name_procedure_temporaries(parser_node^.temporaries, new_symbol_table);

	_symbol_table_enter(@symbol_table_global, parser_node^.name, parser_node^.length, symbol_info)
end;

proc elna_type_conditional_statements(parser_node: ^ElnaTreeConditionalStatements, symbol_table: Word);
begin
	.elna_type_conditional_statements_loop;
	elna_type_binary_expression(parser_node^.condition, symbol_table);
	elna_type_statements(parser_node^.statements, symbol_table);

	parser_node := parser_node^.next;
	if parser_node <> nil then
		goto elna_type_conditional_statements_loop
	end
end;

proc elna_type_if_statement(parser_node: ^ElnaTreeIfStatement, symbol_table: Word);
var
	block: ^ElnaTreeConditionalStatements;
begin
	block := parser_node^.conditionals;

	.elna_type_if_statement_conditionals;
	elna_type_conditional_statements(block, symbol_table);

	block := block^.next;
	if block <> nil then
		goto elna_type_if_statement_conditionals
	end;
	block := parser_node^._else;
	if block <> nil then
		elna_type_statements(block, symbol_table)
	end
end;

proc elna_type_return_statement(parser_node: ^ElnaTreeReturnStatement, symbol_table: Word);
begin
	elna_type_binary_expression(parser_node^.returned, symbol_table)
end;

proc elna_type_call(parser_node: Word, symbol_table: Word);
var
	current_argument: Word;
	argument_tree: Word;
begin
	current_argument := 1;

	.elna_type_call_argument;
	argument_tree := _call_get_argument(parser_node, current_argument);

	if argument_tree <> nil then
		elna_type_binary_expression(argument_tree, symbol_table);
		current_argument := current_argument + 1;

		goto elna_type_call_argument
	end
end;

proc elna_type_assign_statement(parser_node: ^ElnaTreeAssignStatement, symbol_table: Word);
begin
	elna_type_designator(parser_node^.assignee, symbol_table);
	elna_type_binary_expression(parser_node^.assignment, symbol_table)
end;

proc elna_type_statement(parser_node: ^ElnaTreeNode, symbol_table: Word);
begin
	(* Skipping goto and label declarations. *)
	if parser_node^.kind = ElnaTreeKind.if_statement then
		elna_type_if_statement(parser_node, symbol_table)
	elsif parser_node^.kind = ElnaTreeKind.return_statement then
		elna_type_return_statement(parser_node, symbol_table)
	elsif parser_node^.kind = ElnaTreeKind.call then
		elna_type_call(parser_node, symbol_table)
	elsif parser_node^.kind = ElnaTreeKind.assign_statement then
		elna_type_assign_statement(parser_node, symbol_table)
	end
end;

proc elna_type_statements(parser_node: ^ElnaTreeStatement, symbol_table: Word);
begin
	.elna_type_statements_loop;
	if parser_node <> nil then
		elna_type_statement(parser_node, symbol_table);

		parser_node := parser_node^.next;
		goto elna_type_statements_loop
	end
end;

proc elna_type_character_literal(parser_node: ^ElnaTreeCharacterLiteral);
var
	symbol_info: ^ElnaSymbolTypeInfo;
begin
	symbol_info := _symbol_table_lookup(@symbol_table_global, "Word", 4);
	parser_node^.type_decoration := symbol_info^._type
end;

proc elna_type_integer_literal(parser_node: ^ElnaTreeIntegerLiteral);
var
	symbol_info: ^ElnaSymbolTypeInfo;
begin
	symbol_info := _symbol_table_lookup(@symbol_table_global, "Word", 4);
	parser_node^.type_decoration := symbol_info^._type
end;

proc elna_type_string_literal(parser_node: ^ElnaTreeStringLiteral);
var
	symbol_info: ^ElnaSymbolTypeInfo;
begin
	symbol_info := _symbol_table_lookup(@symbol_table_global, "Word", 4);
	parser_node^.type_decoration := symbol_info^._type
end;

proc elna_type_boolean_literal(parser_node: ^ElnaTreeBooleanLiteral);
var
	symbol_info: ^ElnaSymbolTypeInfo;
begin
	symbol_info := _symbol_table_lookup(@symbol_table_global, "Bool", 4);
	parser_node^.type_decoration := symbol_info^._type
end;

proc elna_type_nil_literal(parser_node: ^ElnaTreeNilLiteral);
var
	symbol_info: ^ElnaSymbolTypeInfo;
begin
	symbol_info := _symbol_table_lookup(@symbol_table_global, "Pointer", 7);
	parser_node^.type_decoration := symbol_info^._type
end;

proc elna_type_variable_expression(parser_node: ^ElnaTreeVariableExpression, symbol_table: Word);
var
	variable_info: ^ElnaSymbolInfo;
	temporary_info: ^ElnaSymbolTemporaryInfo;
begin
	variable_info := _symbol_table_lookup(symbol_table, parser_node^.name, parser_node^.length);

	if variable_info = nil then
		variable_info := _symbol_table_lookup(@symbol_table_global, parser_node^.name, parser_node^.length)
	end;
	if variable_info^.kind = ElnaSymbolInfoKind.temporary_info then
		temporary_info := variable_info;
		parser_node^.type_decoration := temporary_info^.variable_type
	end
end;

proc elna_type_simple_expression(parser_node: ^ElnaTreeNode, symbol_table: Word);
begin
	if parser_node^.kind = ElnaTreeKind.integer_literal then
		elna_type_integer_literal(parser_node)
	elsif parser_node^.kind = ElnaTreeKind.character_literal then
		elna_type_character_literal(parser_node)
	elsif parser_node^.kind = ElnaTreeKind.string_literal then
		elna_type_string_literal(parser_node)
	elsif parser_node^.kind = ElnaTreeKind.boolean_literal then
		elna_type_boolean_literal(parser_node)
	elsif parser_node^.kind = ElnaTreeKind.null then
		elna_type_nil_literal(parser_node)
	elsif parser_node^.kind = ElnaTreeKind.variable_expression then
		elna_type_variable_expression(parser_node, symbol_table)
	end
end;

proc elna_type_dereference_expression(parser_node: ^ElnaTreeDereferenceExpression, symbol_table: Word);
var
	base_type: ^ElnaType;
	pointer_type: ^ElnaTypePointer;
	dereferenced_expression: ^ElnaTreeExpression;
begin
	elna_type_designator(parser_node^.pointer, symbol_table);

	dereferenced_expression := parser_node^.pointer;
	base_type := dereferenced_expression^.type_decoration;

	(* If check for compatibility, should be removed later. *)
	if base_type^.kind = ElnaTypeKind.pointer then
		pointer_type := base_type;
		base_type := pointer_type^.base;
	end;
	parser_node^.type_decoration := base_type
end;

proc elna_type_field_access_expression(parser_node: ^ElnaTreeFieldAccessExpression, symbol_table: Word);
var
	variable_expression: ^ElnaTreeVariableExpression;
	base_type: Word;
	type_kind: ^ElnaSymbolTypeInfo;
	symbol_info: ^ElnaSymbolInfo;
	aggregate_type: ^ElnaTypeRecord;
	field_count: Word;
	current_field: ^ElnaTypeField;
begin
	base_type := nil;
	variable_expression := parser_node^.aggregate;

	(* Check whether the field access is an enumeration value. *)
	if variable_expression^.kind = ElnaTreeKind.variable_expression then
		symbol_info := _symbol_table_lookup(@symbol_table_global, variable_expression^.name, variable_expression^.length);
		if symbol_info <> nil then
			type_kind := symbol_info;

			if symbol_info^.kind = ElnaSymbolInfoKind.type_info then
				base_type := type_kind^._type
			end
		end
	end;
	(* If the base_type is still nil this is record field access. *)
	if base_type = nil then
		elna_type_designator(parser_node^.aggregate, symbol_table);
		aggregate_type := variable_expression^.type_decoration;

		field_count := aggregate_type^.length;
		current_field := aggregate_type^.members;

		.elna_type_field_access_expression_field;

		if string_compare(parser_node^.field, parser_node^.length, current_field^.name, current_field^.length) = 0 then
			field_count := field_count - 1;
			current_field := current_field + #size(ElnaTypeField);
			goto elna_type_field_access_expression_field
		end;
		base_type := current_field^.field_type
	end;

	parser_node^.type_decoration := base_type
end;

proc elna_type_designator(parser_node: ^ElnaTreeNode, symbol_table: Word);
begin
	if parser_node^.kind = ElnaTreeKind.dereference_expression then
		elna_type_dereference_expression(parser_node, symbol_table)
	elsif parser_node^.kind = ElnaTreeKind.field_access_expression then
		elna_type_field_access_expression(parser_node, symbol_table)
	elsif parser_node^.kind = ElnaTreeKind.call then
		elna_type_call(parser_node, symbol_table)
	else
		elna_type_simple_expression(parser_node, symbol_table)
	end
end;

proc elna_type_unary_expression(parser_node: ^ElnaTreeUnaryExpression, symbol_table: Word);
var
	unary_operand: ^ElnaTreeExpression;
begin
	if parser_node^.kind = ElnaTreeKind.unary_expression then
		unary_operand := parser_node^.operand;
		elna_type_designator(unary_operand, symbol_table);

		parser_node^.type_decoration := unary_operand^.type_decoration
	else
		elna_type_designator(parser_node, symbol_table)
	end
end;

proc elna_type_binary_expression(parser_node: ^ElnaTreeBinaryExpression, symbol_table: Word);
var
	binary_operand: ^ElnaTreeExpression;
begin
	if parser_node^.kind = ElnaTreeKind.binary_expression then
		elna_type_unary_expression(parser_node^.rhs, symbol_table);

		binary_operand := parser_node^.lhs;
		elna_type_unary_expression(binary_operand, symbol_table);

		parser_node^.type_decoration := binary_operand^.type_decoration
	else
		elna_type_unary_expression(parser_node, symbol_table)
	end
end;

proc elna_type_procedure_declaration(parser_node: ^ElnaTreeProcedureDeclaration);
var
	procedure_info: ^ElnaSymbolProcedureInfo;
	symbol_table: Word;
begin
	procedure_info := _symbol_table_lookup(@symbol_table_global, parser_node^.name, parser_node^.length);
	symbol_table := procedure_info^.symbol_table;

	elna_type_statements(parser_node^.body, symbol_table)
end;

proc elna_name_module_declaration(parser_node: ^ElnaTreeModuleDeclaration);
var
	current_part: ^ElnaTreeDeclaration;
begin
	current_part := parser_node^.types;
	.elna_name_module_declaration_type;
	if current_part <> nil then
		elna_name_type_declaration(current_part);
		current_part := current_part^.next;

		goto elna_name_module_declaration_type
	end;
	current_part := parser_node^.globals;
	.elna_name_module_declaration_global;
	if current_part <> nil then
		elna_name_procedure_temporary(current_part, 0, @symbol_table_global);
		current_part := current_part^.next;

		goto elna_name_module_declaration_global
	end;
	current_part := parser_node^.procedures;
	.elna_name_module_declaration_procedure;
	if current_part <> nil then
		elna_name_procedure_declaration(current_part);
		current_part := current_part^.next;

		goto elna_name_module_declaration_procedure
	end
end;

proc elna_type_module_declaration(parser_node: ^ElnaTreeModuleDeclaration);
var
	current_part: ^ElnaTreeDeclaration;
begin
	current_part := parser_node^.types;
	.elna_type_module_declaration_type;
	if current_part <> 0 then
		elna_type_type_declaration(current_part);
		current_part := current_part^.next;

		goto elna_type_module_declaration_type
	end;

	current_part := parser_node^.procedures;
	.elna_type_module_declaration_procedure;
	if current_part <> 0 then
		elna_type_procedure_declaration(current_part);
		current_part := current_part^.next;

		goto elna_type_module_declaration_procedure
	end
end;

proc _compile();
var
	parser_node: Word;
	tac: Word;
	rtl: Word;
	error_list: ^ElnaErrorList;
	compiled: Word;
begin
	error_list := malloc(#size(ElnaErrorList));
	error_list^.first := nil;
	error_list^.last := nil;

	parser_node := elna_parser_module_declaration(error_list);
	compiled := error_list^.first = nil;

	if compiled then
		elna_name_module_declaration(parser_node);
		elna_type_module_declaration(parser_node);
		tac := elna_tac_module_declaration(parser_node);
		rtl := elna_rtl_module_declaration(tac);
		elna_alloc_module(rtl);
		elna_riscv_module(rtl);
	end;

	return compiled
end;

(**
 * Looks for a symbol in the given symbol table.
 *
 * Parameters:
 * symbol_table - Symbol table.
 * symbol_name - Symbol name pointer.
 * name_length - Symbol name length.
 *
 * Returns the symbol pointer or 0 in a0.
 *)
proc _symbol_table_lookup(symbol_table: Word, symbol_name: Word, name_length: Word);
var
	result: Word;
	symbol_table_length: Word;
	current_name: Word;
	current_length: Word;
begin
	result := 0;

	(* The first word in the symbol table is its length, get it. *)
	symbol_table_length := symbol_table^;

	(* Go to the first symbol position. *)
	symbol_table := symbol_table + 4;

	.symbol_table_lookup_loop;
	if symbol_table_length = 0 then
		goto symbol_table_lookup_end
	end;

	(* Symbol name pointer and length. *)
	current_name := symbol_table^;
	current_length := symbol_table + 4;
	current_length := current_length^;

	(* If lengths don't match, exit and return nil. *)
	if name_length <> current_length then
		goto symbol_table_lookup_repeat
	end;
	(* If names don't match, exit and return nil. *)
	if memcmp(symbol_name, current_name, name_length) then
		goto symbol_table_lookup_repeat
	end;
	(* Otherwise, the symbol is found. *)
	result := symbol_table + 8;
	result := result^;
	goto symbol_table_lookup_end;

	.symbol_table_lookup_repeat;
	symbol_table := symbol_table + 12;
	symbol_table_length := symbol_table_length - 1;
	goto symbol_table_lookup_loop;

	.symbol_table_lookup_end;
	return result
end;

(**
 * Create a new local symbol table in the symbol memory region after the last
 * known symbol table.
 *)
proc _symbol_table_create();
var
	new_symbol_table: Word;
	table_length: Word;
	current_table: Word;
begin
	new_symbol_table := symbol_table_store;

	.symbol_table_create_loop;
	table_length := new_symbol_table^;

	if table_length <> 0 then
		table_length := table_length * 12;
		table_length := table_length + 4;
		new_symbol_table := new_symbol_table + table_length;
		goto symbol_table_create_loop
	end;

	return new_symbol_table
end;

(**
 * Inserts a symbol into the table.
 *
 * Parameters:
 * symbol_table - Symbol table.
 * symbol_name - Symbol name pointer.
 * name_length - Symbol name length.
 * symbol - Symbol pointer.
 *)
proc _symbol_table_enter(symbol_table: Word, symbol_name: Word, name_length: Word, symbol: Word);
var
	table_length: Word;
	symbol_pointer: Word;
begin
	(* The first word in the symbol table is its length, get it. *)
	table_length := symbol_table^;

	(* Calculate the offset for the new symbol. *)
	symbol_pointer := table_length * 12;
	symbol_pointer := symbol_pointer + 4;
	symbol_pointer := symbol_table + symbol_pointer;

	symbol_pointer^ := symbol_name;
	symbol_pointer := symbol_pointer + 4;
	symbol_pointer^ := name_length;
	symbol_pointer := symbol_pointer + 4;
	symbol_pointer^ := symbol;

	(* Increment the symbol table length. *)
	table_length := table_length + 1;
	symbol_table^ := table_length
end;

proc _symbol_table_build();
var
	current_info: ^ElnaSymbolTypeInfo;
	current_type: ^ElnaType;
begin
	(* Set the table length to 0. *)
	symbol_table_global := 0;

	(* Enter built-in symbols. *)
	current_type := malloc(#size(ElnaType));
	current_type^.kind := ElnaTypeKind.primitive;
	current_type^.size := 4;
	current_info := _type_info_create(current_type);
	_symbol_table_enter(@symbol_table_global, "Word", 4, current_info);

	current_type := malloc(#size(ElnaType));
	current_type^.kind := ElnaTypeKind.primitive;
	current_type^.size := 4;
	current_info := _type_info_create(current_type);
	_symbol_table_enter(@symbol_table_global, "Pointer", 7, current_info);

	current_type := malloc(#size(ElnaType));
	current_type^.kind := ElnaTypeKind.primitive;
	current_type^.size := 1;
	current_info := _type_info_create(current_type);
	_symbol_table_enter(@symbol_table_global, "Bool", 4, current_info);

	current_type := malloc(#size(ElnaType));
	current_type^.kind := ElnaTypeKind.primitive;
	current_type^.size := 4096;
	current_info := _type_info_create(current_type);
	_symbol_table_enter(@symbol_table_global, "Array", 5, current_info)
end;

(**
 * Assigns some value to at array index.
 *
 * Parameters:
 * array - Array pointer.
 * index - Index (word offset into the array).
 * data - Data to assign.
 *)
proc _assign_at(array: Word, index: Word, data: Word);
var
	target: Word;
begin
	target := index - 1;
	target := target * 4;
	target := array + target;

	target^ := data
end;

proc _get_at(array: Word, index: Word);
var
	target: Word;
begin
	target := index - 1;
	target := target * 4;
	target := array + target;

	return target^
end;

(**
 * Initializes the array with character classes.
 *)
proc _elna_lexer_classifications();
var
	code: Word;
begin
	_assign_at(@classification, 1, ElnaLexerClass.eof);
	_assign_at(@classification, 2, ElnaLexerClass.invalid);
	_assign_at(@classification, 3, ElnaLexerClass.invalid);
	_assign_at(@classification, 4, ElnaLexerClass.invalid);
	_assign_at(@classification, 5, ElnaLexerClass.invalid);
	_assign_at(@classification, 6, ElnaLexerClass.invalid);
	_assign_at(@classification, 7, ElnaLexerClass.invalid);
	_assign_at(@classification, 8, ElnaLexerClass.invalid);
	_assign_at(@classification, 9, ElnaLexerClass.invalid);
	_assign_at(@classification, 10, ElnaLexerClass.space);
	_assign_at(@classification, 11, ElnaLexerClass.space);
	_assign_at(@classification, 12, ElnaLexerClass.invalid);
	_assign_at(@classification, 13, ElnaLexerClass.invalid);
	_assign_at(@classification, 14, ElnaLexerClass.space);
	_assign_at(@classification, 15, ElnaLexerClass.invalid);
	_assign_at(@classification, 16, ElnaLexerClass.invalid);
	_assign_at(@classification, 17, ElnaLexerClass.invalid);
	_assign_at(@classification, 18, ElnaLexerClass.invalid);
	_assign_at(@classification, 19, ElnaLexerClass.invalid);
	_assign_at(@classification, 20, ElnaLexerClass.invalid);
	_assign_at(@classification, 21, ElnaLexerClass.invalid);
	_assign_at(@classification, 22, ElnaLexerClass.invalid);
	_assign_at(@classification, 23, ElnaLexerClass.invalid);
	_assign_at(@classification, 24, ElnaLexerClass.invalid);
	_assign_at(@classification, 25, ElnaLexerClass.invalid);
	_assign_at(@classification, 26, ElnaLexerClass.invalid);
	_assign_at(@classification, 27, ElnaLexerClass.invalid);
	_assign_at(@classification, 28, ElnaLexerClass.invalid);
	_assign_at(@classification, 29, ElnaLexerClass.invalid);
	_assign_at(@classification, 30, ElnaLexerClass.invalid);
	_assign_at(@classification, 31, ElnaLexerClass.invalid);
	_assign_at(@classification, 32, ElnaLexerClass.invalid);
	_assign_at(@classification, 33, ElnaLexerClass.space);
	_assign_at(@classification, 34, ElnaLexerClass.single);
	_assign_at(@classification, 35, ElnaLexerClass.double_quote);
	_assign_at(@classification, 36, ElnaLexerClass.number_sign);
	_assign_at(@classification, 37, ElnaLexerClass.other);
	_assign_at(@classification, 38, ElnaLexerClass.single);
	_assign_at(@classification, 39, ElnaLexerClass.single);
	_assign_at(@classification, 40, ElnaLexerClass.single_quote);
	_assign_at(@classification, 41, ElnaLexerClass.left_paren);
	_assign_at(@classification, 42, ElnaLexerClass.right_paren);
	_assign_at(@classification, 43, ElnaLexerClass.asterisk);
	_assign_at(@classification, 44, ElnaLexerClass.single);
	_assign_at(@classification, 45, ElnaLexerClass.single);
	_assign_at(@classification, 46, ElnaLexerClass.minus);
	_assign_at(@classification, 47, ElnaLexerClass.dot);
	_assign_at(@classification, 48, ElnaLexerClass.single);
	_assign_at(@classification, 49, ElnaLexerClass.zero);
	_assign_at(@classification, 50, ElnaLexerClass.digit);
	_assign_at(@classification, 51, ElnaLexerClass.digit);
	_assign_at(@classification, 52, ElnaLexerClass.digit);
	_assign_at(@classification, 53, ElnaLexerClass.digit);
	_assign_at(@classification, 54, ElnaLexerClass.digit);
	_assign_at(@classification, 55, ElnaLexerClass.digit);
	_assign_at(@classification, 56, ElnaLexerClass.digit);
	_assign_at(@classification, 57, ElnaLexerClass.digit);
	_assign_at(@classification, 58, ElnaLexerClass.digit);
	_assign_at(@classification, 59, ElnaLexerClass.colon);
	_assign_at(@classification, 60, ElnaLexerClass.single);
	_assign_at(@classification, 61, ElnaLexerClass.less);
	_assign_at(@classification, 62, ElnaLexerClass.equals);
	_assign_at(@classification, 63, ElnaLexerClass.greater);
	_assign_at(@classification, 64, ElnaLexerClass.other);
	_assign_at(@classification, 65, ElnaLexerClass.single);
	_assign_at(@classification, 66, ElnaLexerClass.alpha);
	_assign_at(@classification, 67, ElnaLexerClass.alpha);
	_assign_at(@classification, 68, ElnaLexerClass.alpha);
	_assign_at(@classification, 69, ElnaLexerClass.alpha);
	_assign_at(@classification, 70, ElnaLexerClass.alpha);
	_assign_at(@classification, 71, ElnaLexerClass.alpha);
	_assign_at(@classification, 72, ElnaLexerClass.alpha);
	_assign_at(@classification, 73, ElnaLexerClass.alpha);
	_assign_at(@classification, 74, ElnaLexerClass.alpha);
	_assign_at(@classification, 75, ElnaLexerClass.alpha);
	_assign_at(@classification, 76, ElnaLexerClass.alpha);
	_assign_at(@classification, 77, ElnaLexerClass.alpha);
	_assign_at(@classification, 78, ElnaLexerClass.alpha);
	_assign_at(@classification, 79, ElnaLexerClass.alpha);
	_assign_at(@classification, 80, ElnaLexerClass.alpha);
	_assign_at(@classification, 81, ElnaLexerClass.alpha);
	_assign_at(@classification, 82, ElnaLexerClass.alpha);
	_assign_at(@classification, 83, ElnaLexerClass.alpha);
	_assign_at(@classification, 84, ElnaLexerClass.alpha);
	_assign_at(@classification, 85, ElnaLexerClass.alpha);
	_assign_at(@classification, 86, ElnaLexerClass.alpha);
	_assign_at(@classification, 87, ElnaLexerClass.alpha);
	_assign_at(@classification, 88, ElnaLexerClass.alpha);
	_assign_at(@classification, 89, ElnaLexerClass.alpha);
	_assign_at(@classification, 90, ElnaLexerClass.alpha);
	_assign_at(@classification, 91, ElnaLexerClass.alpha);
	_assign_at(@classification, 92, ElnaLexerClass.single);
	_assign_at(@classification, 93, ElnaLexerClass.backslash);
	_assign_at(@classification, 94, ElnaLexerClass.single);
	_assign_at(@classification, 95, ElnaLexerClass.single);
	_assign_at(@classification, 96, ElnaLexerClass.alpha);
	_assign_at(@classification, 97, ElnaLexerClass.other);
	_assign_at(@classification, 98, ElnaLexerClass.hex);
	_assign_at(@classification, 99, ElnaLexerClass.hex);
	_assign_at(@classification, 100, ElnaLexerClass.hex);
	_assign_at(@classification, 101, ElnaLexerClass.hex);
	_assign_at(@classification, 102, ElnaLexerClass.hex);
	_assign_at(@classification, 103, ElnaLexerClass.hex);
	_assign_at(@classification, 104, ElnaLexerClass.alpha);
	_assign_at(@classification, 105, ElnaLexerClass.alpha);
	_assign_at(@classification, 106, ElnaLexerClass.alpha);
	_assign_at(@classification, 107, ElnaLexerClass.alpha);
	_assign_at(@classification, 108, ElnaLexerClass.alpha);
	_assign_at(@classification, 109, ElnaLexerClass.alpha);
	_assign_at(@classification, 110, ElnaLexerClass.alpha);
	_assign_at(@classification, 111, ElnaLexerClass.alpha);
	_assign_at(@classification, 112, ElnaLexerClass.alpha);
	_assign_at(@classification, 113, ElnaLexerClass.alpha);
	_assign_at(@classification, 114, ElnaLexerClass.alpha);
	_assign_at(@classification, 115, ElnaLexerClass.alpha);
	_assign_at(@classification, 116, ElnaLexerClass.alpha);
	_assign_at(@classification, 117, ElnaLexerClass.alpha);
	_assign_at(@classification, 118, ElnaLexerClass.alpha);
	_assign_at(@classification, 119, ElnaLexerClass.alpha);
	_assign_at(@classification, 120, ElnaLexerClass.alpha);
	_assign_at(@classification, 121, ElnaLexerClass.x);
	_assign_at(@classification, 122, ElnaLexerClass.alpha);
	_assign_at(@classification, 123, ElnaLexerClass.alpha);
	_assign_at(@classification, 124, ElnaLexerClass.other);
	_assign_at(@classification, 125, ElnaLexerClass.single);
	_assign_at(@classification, 126, ElnaLexerClass.other);
	_assign_at(@classification, 127, ElnaLexerClass.single);
	_assign_at(@classification, 128, ElnaLexerClass.invalid);

	code := 129;

	(* Set the remaining 129 - 256 bytes to transitionClassOther. *)
	.create_classification_loop;
	_assign_at(@classification, code, ElnaLexerClass.other);
	code := code + 1;

	if code < 257 then
		goto create_classification_loop
	end
end;

proc _elna_lexer_get_transition(current_state: Word, character_class: Word);
var
	transition_table: Word;
	row_position: Word;
	column_position: Word;
	target: Word;
begin
	(* Each state is 8 bytes long (2 words: action and next state).
	There are 23 character classes, so a transition row 8 * 23 = 184 bytes long. *)
	row_position := current_state - 1;
	row_position := row_position * 184;

	column_position := character_class - 1;
	column_position := column_position * 8;

	target := _elna_lexer_get_transition_table();
	target := target + row_position;

	return target + column_position
end;

(**
 * Parameters:
 * current_state - First index into transitions table.
 * character_class - Second index into transitions table.
 * action - Action to assign.
 * next_state - Next state to assign.
 *)
proc _elna_lexer_set_transition(current_state: Word, character_class: Word, action: Word, next_state: Word);
var
	transition: Word;
begin
	transition := _elna_lexer_get_transition(current_state, character_class);

	_elna_lexer_transition_set_action(transition, action);
	_elna_lexer_transition_set_state(transition, next_state)
end;

(* Sets same action and state transition for all character classes in one transition row. *)

(**
 * Parameters:
 * current_state - Current state (Transition state enumeration).
 * default_action - Default action (Callback).
 * next_state - Next state (Transition state enumeration).
 *)
proc _elna_lexer_default_transition(current_state: Word, default_action: Word, next_state: Word);
begin
	_elna_lexer_set_transition(current_state, ElnaLexerClass.invalid, default_action, next_state);
	_elna_lexer_set_transition(current_state, ElnaLexerClass.digit, default_action, next_state);
	_elna_lexer_set_transition(current_state, ElnaLexerClass.alpha, default_action, next_state);
	_elna_lexer_set_transition(current_state, ElnaLexerClass.space, default_action, next_state);
	_elna_lexer_set_transition(current_state, ElnaLexerClass.colon, default_action, next_state);
	_elna_lexer_set_transition(current_state, ElnaLexerClass.equals, default_action, next_state);
	_elna_lexer_set_transition(current_state, ElnaLexerClass.left_paren, default_action, next_state);
	_elna_lexer_set_transition(current_state, ElnaLexerClass.right_paren, default_action, next_state);
	_elna_lexer_set_transition(current_state, ElnaLexerClass.asterisk, default_action, next_state);
	_elna_lexer_set_transition(current_state, ElnaLexerClass.backslash, default_action, next_state);
	_elna_lexer_set_transition(current_state, ElnaLexerClass.single, default_action, next_state);
	_elna_lexer_set_transition(current_state, ElnaLexerClass.hex, default_action, next_state);
	_elna_lexer_set_transition(current_state, ElnaLexerClass.zero, default_action, next_state);
	_elna_lexer_set_transition(current_state, ElnaLexerClass.x, default_action, next_state);
	_elna_lexer_set_transition(current_state, ElnaLexerClass.eof, default_action, next_state);
	_elna_lexer_set_transition(current_state, ElnaLexerClass.dot, default_action, next_state);
	_elna_lexer_set_transition(current_state, ElnaLexerClass.minus, default_action, next_state);
	_elna_lexer_set_transition(current_state, ElnaLexerClass.single_quote, default_action, next_state);
	_elna_lexer_set_transition(current_state, ElnaLexerClass.double_quote, default_action, next_state);
	_elna_lexer_set_transition(current_state, ElnaLexerClass.greater, default_action, next_state);
	_elna_lexer_set_transition(current_state, ElnaLexerClass.less, default_action, next_state);
	_elna_lexer_set_transition(current_state, ElnaLexerClass.other, default_action, next_state);
	_elna_lexer_set_transition(current_state, ElnaLexerClass.number_sign, default_action, next_state)
end;

(**
 * The transition table describes transitions from one state to another, given
 * a symbol (character class).
 *
 * The table has m rows and n columns, where m is the amount of states and n is
 * the amount of classes. So given the current state and a classified character
 * the table can be used to look up the next state.
 *)
proc _elna_lexer_transitions();
begin
	(* Start state. *)
	_elna_lexer_set_transition(ElnaLexerState.start, ElnaLexerClass.invalid, ElnaLexerAction.none, ElnaLexerState.finish);
	_elna_lexer_set_transition(ElnaLexerState.start, ElnaLexerClass.digit, ElnaLexerAction.accumulate, ElnaLexerState.decimal);
	_elna_lexer_set_transition(ElnaLexerState.start, ElnaLexerClass.alpha, ElnaLexerAction.accumulate, ElnaLexerState.identifier);
	_elna_lexer_set_transition(ElnaLexerState.start, ElnaLexerClass.space, ElnaLexerAction.skip, ElnaLexerState.start);
	_elna_lexer_set_transition(ElnaLexerState.start, ElnaLexerClass.colon, ElnaLexerAction.accumulate, ElnaLexerState.colon);
	_elna_lexer_set_transition(ElnaLexerState.start, ElnaLexerClass.equals, ElnaLexerAction.single, ElnaLexerState.finish);
	_elna_lexer_set_transition(ElnaLexerState.start, ElnaLexerClass.left_paren, ElnaLexerAction.accumulate, ElnaLexerState.left_paren);
	_elna_lexer_set_transition(ElnaLexerState.start, ElnaLexerClass.right_paren, ElnaLexerAction.single, ElnaLexerState.finish);
	_elna_lexer_set_transition(ElnaLexerState.start, ElnaLexerClass.asterisk, ElnaLexerAction.single, ElnaLexerState.finish);
	_elna_lexer_set_transition(ElnaLexerState.start, ElnaLexerClass.backslash, ElnaLexerAction.none, ElnaLexerState.finish);
	_elna_lexer_set_transition(ElnaLexerState.start, ElnaLexerClass.single, ElnaLexerAction.single, ElnaLexerState.finish);
	_elna_lexer_set_transition(ElnaLexerState.start, ElnaLexerClass.hex, ElnaLexerAction.accumulate, ElnaLexerState.identifier);
	_elna_lexer_set_transition(ElnaLexerState.start, ElnaLexerClass.zero, ElnaLexerAction.accumulate, ElnaLexerState.leading_zero);
	_elna_lexer_set_transition(ElnaLexerState.start, ElnaLexerClass.x, ElnaLexerAction.accumulate, ElnaLexerState.identifier);
	_elna_lexer_set_transition(ElnaLexerState.start, ElnaLexerClass.eof, ElnaLexerAction.eof, ElnaLexerState.finish);
	_elna_lexer_set_transition(ElnaLexerState.start, ElnaLexerClass.dot, ElnaLexerAction.single, ElnaLexerState.finish);
	_elna_lexer_set_transition(ElnaLexerState.start, ElnaLexerClass.minus, ElnaLexerAction.accumulate, ElnaLexerState.minus);
	_elna_lexer_set_transition(ElnaLexerState.start, ElnaLexerClass.single_quote, ElnaLexerAction.accumulate, ElnaLexerState.character);
	_elna_lexer_set_transition(ElnaLexerState.start, ElnaLexerClass.double_quote, ElnaLexerAction.accumulate, ElnaLexerState.string);
	_elna_lexer_set_transition(ElnaLexerState.start, ElnaLexerClass.greater, ElnaLexerAction.accumulate, ElnaLexerState.greater);
	_elna_lexer_set_transition(ElnaLexerState.start, ElnaLexerClass.less, ElnaLexerAction.accumulate, ElnaLexerState.less);
	_elna_lexer_set_transition(ElnaLexerState.start, ElnaLexerClass.other, ElnaLexerAction.none, ElnaLexerState.finish);
	_elna_lexer_set_transition(ElnaLexerState.start, ElnaLexerClass.number_sign, ElnaLexerAction.accumulate, ElnaLexerState.number_sign);

	(* Colon state. *)
	_elna_lexer_default_transition(ElnaLexerState.colon, ElnaLexerAction.finalize, ElnaLexerState.finish);
	_elna_lexer_set_transition(ElnaLexerState.colon, ElnaLexerClass.equals, ElnaLexerAction.composite, ElnaLexerState.finish);

	(* Identifier state. *)
	_elna_lexer_default_transition(ElnaLexerState.identifier, ElnaLexerAction.key_id, ElnaLexerState.finish);
	_elna_lexer_set_transition(ElnaLexerState.identifier, ElnaLexerClass.digit, ElnaLexerAction.accumulate, ElnaLexerState.identifier);
	_elna_lexer_set_transition(ElnaLexerState.identifier, ElnaLexerClass.alpha, ElnaLexerAction.accumulate, ElnaLexerState.identifier);
	_elna_lexer_set_transition(ElnaLexerState.identifier, ElnaLexerClass.hex, ElnaLexerAction.accumulate, ElnaLexerState.identifier);
	_elna_lexer_set_transition(ElnaLexerState.identifier, ElnaLexerClass.zero, ElnaLexerAction.accumulate, ElnaLexerState.identifier);
	_elna_lexer_set_transition(ElnaLexerState.identifier, ElnaLexerClass.x, ElnaLexerAction.accumulate, ElnaLexerState.identifier);

	(* Decimal state. *)
	_elna_lexer_default_transition(ElnaLexerState.decimal, ElnaLexerAction.integer, ElnaLexerState.finish);
	_elna_lexer_set_transition(ElnaLexerState.decimal, ElnaLexerClass.digit, ElnaLexerAction.accumulate, ElnaLexerState.decimal);
	_elna_lexer_set_transition(ElnaLexerState.decimal, ElnaLexerClass.alpha, ElnaLexerAction.none, ElnaLexerState.finish);
	_elna_lexer_set_transition(ElnaLexerState.decimal, ElnaLexerClass.hex, ElnaLexerAction.none, ElnaLexerState.finish);
	_elna_lexer_set_transition(ElnaLexerState.decimal, ElnaLexerClass.zero, ElnaLexerAction.accumulate, ElnaLexerState.decimal);
	_elna_lexer_set_transition(ElnaLexerState.decimal, ElnaLexerClass.x, ElnaLexerAction.none, ElnaLexerState.finish);

	(* Leading zero. *)
	_elna_lexer_default_transition(ElnaLexerState.leading_zero, ElnaLexerAction.integer, ElnaLexerState.finish);
	_elna_lexer_set_transition(ElnaLexerState.leading_zero, ElnaLexerClass.digit, ElnaLexerAction.none, ElnaLexerState.finish);
	_elna_lexer_set_transition(ElnaLexerState.leading_zero, ElnaLexerClass.alpha, ElnaLexerAction.none, ElnaLexerState.finish);
	_elna_lexer_set_transition(ElnaLexerState.leading_zero, ElnaLexerClass.hex, ElnaLexerAction.none, ElnaLexerState.finish);
	_elna_lexer_set_transition(ElnaLexerState.leading_zero, ElnaLexerClass.zero, ElnaLexerAction.none, ElnaLexerState.finish);
	_elna_lexer_set_transition(ElnaLexerState.leading_zero, ElnaLexerClass.x, ElnaLexerAction.none, ElnaLexerState.dot);

	(* Greater state. *)
	_elna_lexer_default_transition(ElnaLexerState.greater, ElnaLexerAction.finalize, ElnaLexerState.finish);
	_elna_lexer_set_transition(ElnaLexerState.greater, ElnaLexerClass.equals, ElnaLexerAction.composite, ElnaLexerState.finish);

	(* Minus state. *)
	_elna_lexer_default_transition(ElnaLexerState.minus, ElnaLexerAction.finalize, ElnaLexerState.finish);
	_elna_lexer_set_transition(ElnaLexerState.minus, ElnaLexerClass.greater, ElnaLexerAction.composite, ElnaLexerState.finish);

	(* Left paren state. *)
	_elna_lexer_default_transition(ElnaLexerState.left_paren, ElnaLexerAction.finalize, ElnaLexerState.finish);
	_elna_lexer_set_transition(ElnaLexerState.left_paren, ElnaLexerClass.asterisk, ElnaLexerAction.accumulate, ElnaLexerState.comment);

	(* Less state. *)
	_elna_lexer_default_transition(ElnaLexerState.less, ElnaLexerAction.finalize, ElnaLexerState.finish);
	_elna_lexer_set_transition(ElnaLexerState.less, ElnaLexerClass.equals, ElnaLexerAction.composite, ElnaLexerState.finish);
	_elna_lexer_set_transition(ElnaLexerState.less, ElnaLexerClass.greater, ElnaLexerAction.composite, ElnaLexerState.finish);

	(* Hexadecimal after 0x. *)
	_elna_lexer_default_transition(ElnaLexerState.dot, ElnaLexerAction.finalize, ElnaLexerState.finish);
	_elna_lexer_set_transition(ElnaLexerState.dot, ElnaLexerClass.dot, ElnaLexerAction.composite, ElnaLexerState.finish);

	(* Comment. *)
	_elna_lexer_default_transition(ElnaLexerState.comment, ElnaLexerAction.accumulate, ElnaLexerState.comment);
	_elna_lexer_set_transition(ElnaLexerState.comment, ElnaLexerClass.asterisk, ElnaLexerAction.accumulate, ElnaLexerState.closing_comment);
	_elna_lexer_set_transition(ElnaLexerState.comment, ElnaLexerClass.eof, ElnaLexerAction.none, ElnaLexerState.finish);

	(* Closing comment. *)
	_elna_lexer_default_transition(ElnaLexerState.closing_comment, ElnaLexerAction.accumulate, ElnaLexerState.comment);
	_elna_lexer_set_transition(ElnaLexerState.closing_comment, ElnaLexerClass.invalid, ElnaLexerAction.none, ElnaLexerState.finish);
	_elna_lexer_set_transition(ElnaLexerState.closing_comment, ElnaLexerClass.right_paren, ElnaLexerAction.delimited, ElnaLexerState.finish);
	_elna_lexer_set_transition(ElnaLexerState.closing_comment, ElnaLexerClass.asterisk, ElnaLexerAction.accumulate, ElnaLexerState.closing_comment);
	_elna_lexer_set_transition(ElnaLexerState.closing_comment, ElnaLexerClass.eof, ElnaLexerAction.none, ElnaLexerState.finish);

	(* Character. *)
	_elna_lexer_default_transition(ElnaLexerState.character, ElnaLexerAction.accumulate, ElnaLexerState.character);
	_elna_lexer_set_transition(ElnaLexerState.character, ElnaLexerClass.invalid, ElnaLexerAction.none, ElnaLexerState.finish);
	_elna_lexer_set_transition(ElnaLexerState.character, ElnaLexerClass.eof, ElnaLexerAction.none, ElnaLexerState.finish);
	_elna_lexer_set_transition(ElnaLexerState.character, ElnaLexerClass.single_quote, ElnaLexerAction.delimited, ElnaLexerState.finish);
	_elna_lexer_set_transition(ElnaLexerState.character, ElnaLexerClass.backslash, ElnaLexerAction.accumulate, ElnaLexerState.character_escape);

	(* Escape sequence in a character. *)
	_elna_lexer_default_transition(ElnaLexerState.character_escape, ElnaLexerAction.accumulate, ElnaLexerState.character);
	_elna_lexer_set_transition(ElnaLexerState.character_escape, ElnaLexerClass.invalid, ElnaLexerAction.none, ElnaLexerState.finish);
	_elna_lexer_set_transition(ElnaLexerState.character_escape, ElnaLexerClass.eof, ElnaLexerAction.none, ElnaLexerState.finish);

	(* String. *)
	_elna_lexer_default_transition(ElnaLexerState.string, ElnaLexerAction.accumulate, ElnaLexerState.string);
	_elna_lexer_set_transition(ElnaLexerState.string, ElnaLexerClass.invalid, ElnaLexerAction.none, ElnaLexerState.finish);
	_elna_lexer_set_transition(ElnaLexerState.string, ElnaLexerClass.eof, ElnaLexerAction.none, ElnaLexerState.finish);
	_elna_lexer_set_transition(ElnaLexerState.string, ElnaLexerClass.double_quote, ElnaLexerAction.delimited, ElnaLexerState.finish);
	_elna_lexer_set_transition(ElnaLexerState.string, ElnaLexerClass.backslash, ElnaLexerAction.accumulate, ElnaLexerState.string_escape);

	(* Escape sequence in a string. *)
	_elna_lexer_default_transition(ElnaLexerState.string_escape, ElnaLexerAction.accumulate, ElnaLexerState.string);
	_elna_lexer_set_transition(ElnaLexerState.string_escape, ElnaLexerClass.invalid, ElnaLexerAction.none, ElnaLexerState.finish);
	_elna_lexer_set_transition(ElnaLexerState.string_escape, ElnaLexerClass.eof, ElnaLexerAction.none, ElnaLexerState.finish);

	(* Number sign state. *)
	_elna_lexer_default_transition(ElnaLexerState.number_sign, ElnaLexerAction.key_id, ElnaLexerState.finish);
	_elna_lexer_set_transition(ElnaLexerState.number_sign, ElnaLexerClass.alpha, ElnaLexerAction.accumulate, ElnaLexerState.trait);
	_elna_lexer_set_transition(ElnaLexerState.number_sign, ElnaLexerClass.hex, ElnaLexerAction.accumulate, ElnaLexerState.trait);
	_elna_lexer_set_transition(ElnaLexerState.number_sign, ElnaLexerClass.x, ElnaLexerAction.accumulate, ElnaLexerState.trait);

	(* Trait state. *)
	_elna_lexer_default_transition(ElnaLexerState.trait, ElnaLexerAction.key_id, ElnaLexerState.finish);
	_elna_lexer_set_transition(ElnaLexerState.trait, ElnaLexerClass.digit, ElnaLexerAction.accumulate, ElnaLexerState.trait);
	_elna_lexer_set_transition(ElnaLexerState.trait, ElnaLexerClass.alpha, ElnaLexerAction.accumulate, ElnaLexerState.trait);
	_elna_lexer_set_transition(ElnaLexerState.trait, ElnaLexerClass.hex, ElnaLexerAction.accumulate, ElnaLexerState.trait);
	_elna_lexer_set_transition(ElnaLexerState.trait, ElnaLexerClass.zero, ElnaLexerAction.accumulate, ElnaLexerState.trait);
	_elna_lexer_set_transition(ElnaLexerState.trait, ElnaLexerClass.x, ElnaLexerAction.accumulate, ElnaLexerState.trait)
end;

(**
 * Transition table is saved after character classification table.
 * Each character entry is 1 word long and there are 256 characters.
 * 1024 = 256 * 4
 *)
proc _elna_lexer_get_transition_table();
	return @classification + 1024
end;

(**
 * Lexer state is saved after the transition tables.
 * Each transition table entry is 8 bytes long. The table has 19 rows (transition states)
 * and 23 columns (character classes), so 3496 = 8 * 19 * 23.
 *)
proc _elna_lexer_global_state();
var
	result: Word;
begin
	result := _elna_lexer_get_transition_table();
	return  result + 3496
end;

(**
 * Gets pointer to the token start.
 *)
proc _elna_lexer_global_get_start();
var
	target: Word;
begin
	target := _elna_lexer_global_state() + 4;
	return target^
end;

(**
 * Sets pointer to the token start.
 *)
proc _elna_lexer_global_set_start(new_start: Word);
var
	target: Word;
begin
	target := _elna_lexer_global_state() + 4;
	target^ := new_start
end;

(**
 * Gets pointer to the token end.
 *)
proc _elna_lexer_global_get_end();
var
	target: Word;
begin
	target := _elna_lexer_global_state() + 8;
	return target^
end;

(**
 * Sets pointer to the token end.
 *)
proc _elna_lexer_global_set_end(new_start: Word);
var
	target: Word;
begin
	target := _elna_lexer_global_state() + 8;
	target^ := new_start
end;

proc _elna_lexer_transition_get_action(this: Word);
	return this^
end;

proc _elna_lexer_transition_set_action(this: Word, value: Word);
begin
	this^ := value
end;

proc _elna_lexer_transition_get_state(this: Word);
begin
	this := this + 4;
	return this^
end;

proc _elna_lexer_transition_set_state(this: Word, value: Word);
begin
	this := this + 4;
	this^ := value
end;

(**
 * Resets the lexer state for reading the next token.
 *)
proc _elna_lexer_reset();
var
	state: Word;
begin
	(* Transition start state is 1. *)
	state := _elna_lexer_global_state();
	state^ := ElnaLexerState.start;

	state := _elna_lexer_global_get_start();
	_elna_lexer_global_set_end(state)
end;

(**
 * One time lexer initialization.
 *)
proc _elna_lexer_initialize(code_pointer: Word);
begin
	_elna_lexer_classifications();
	_elna_lexer_transitions();

	_elna_lexer_global_set_start(code_pointer);
	_elna_lexer_global_set_end(code_pointer)
end;

proc _elna_lexer_next_transition();
var
	current_character: Word;
	character_class: Word;
	current_state: Word;
begin
	current_character := _elna_lexer_global_get_end();
	current_character := _load_byte(current_character);

	character_class := _get_at(@classification, current_character + 1);

	current_state := _elna_lexer_global_state();
	current_state := current_state^;

	return _elna_lexer_get_transition(current_state, character_class)
end;

proc string_compare(lhs_pointer: Word, lhs_length: Word, rhs_pointer: Word, rhs_length: Word);
var
	result: Word;
begin
	result := 0;

	if lhs_length = rhs_length then
		result := memcmp(lhs_pointer, rhs_pointer, lhs_length);
		result := result = 0
	end;
	return result
end;

proc _elna_lexer_classify_keyword(position_start: Word, position_end: Word);
var
	result: Word;
	token_length: Word;
begin
	result := ElnaLexerKind.identifier;
	token_length := position_end - position_start;

	if _load_byte(position_start) = '#' then
		result := ElnaLexerKind.trait
	elsif string_compare(position_start, token_length, "const", 5) then
		result := ElnaLexerKind._const
	elsif string_compare(position_start, token_length, "var", 3) then
		result := ElnaLexerKind._var
	elsif string_compare(position_start, token_length, "proc", 4) then
		result := ElnaLexerKind._proc
	elsif string_compare(position_start, token_length, "type", 4) then
		result := ElnaLexerKind._type
	elsif string_compare(position_start, token_length, "begin", 5) then
		result := ElnaLexerKind._begin
	elsif string_compare(position_start, token_length, "end", 3) then
		result := ElnaLexerKind._end
	elsif string_compare(position_start, token_length, "return", 6) then
		result := ElnaLexerKind._return
	elsif string_compare(position_start, token_length, "goto", 4) then
		result := ElnaLexerKind._goto
	elsif string_compare(position_start, token_length, "if", 2) then
		result := ElnaLexerKind._if
	elsif string_compare(position_start, token_length, "while", 5) then
		result := ElnaLexerKind._while
	elsif string_compare(position_start, token_length, "then", 4) then
		result := ElnaLexerKind._then
	elsif string_compare(position_start, token_length, "else", 4) then
		result := ElnaLexerKind._else
	elsif string_compare(position_start, token_length, "elsif", 5) then
		result := ElnaLexerKind._elsif
	elsif string_compare(position_start, token_length, "record", 6) then
		result := ElnaLexerKind._record
	elsif string_compare(position_start, token_length, "or", 2) then
		result := ElnaLexerKind._or
	elsif string_compare(position_start, token_length, "xor", 3) then
		result := ElnaLexerKind._xor
	elsif string_compare(position_start, token_length, "program", 7) then
		result := ElnaLexerKind._program
	elsif string_compare(position_start, token_length, "module", 6) then
		result := ElnaLexerKind._module
	elsif string_compare(position_start, token_length, "nil", 3) then
		result := ElnaLexerKind.null
	elsif string_compare(position_start, token_length, "true", 4) then
		result := ElnaLexerKind.boolean
	elsif string_compare(position_start, token_length, "false", 5) then
		result := ElnaLexerKind.boolean
	end;
	return result
end;

proc _elna_lexer_classify_finalize(start_position: Word);
var
	character: Word;
	result: Word;
begin
	result := 0;
	character := _load_byte(start_position);

	if character = ':' then
		result := ElnaLexerKind.colon
	elsif character = '.' then
		result := ElnaLexerKind.dot
	elsif character = '(' then
		result := ElnaLexerKind.left_paren
	elsif character = '-' then
		result := ElnaLexerKind.minus
	elsif character = '<' then
		result := ElnaLexerKind.less_than
	elsif character = '>' then
		result := ElnaLexerKind.greater_than
	end;
	return result
end;

proc _elna_lexer_classify_single(start_position: Word);
var
	character: Word;
	result: Word;
begin
	result := 0;
	character := _load_byte(start_position);

	if character = ';' then
		result := ElnaLexerKind.semicolon
	elsif character = ',' then
		result := ElnaLexerKind.comma
	elsif character = ')' then
		result := ElnaLexerKind.right_paren
	elsif character = '@' then
		result := ElnaLexerKind.at
	elsif character = '~' then
		result := ElnaLexerKind.not
	elsif character = '&' then
		result := ElnaLexerKind.and
	elsif character = '+' then
		result := ElnaLexerKind.plus
	elsif character = '*' then
		result := ElnaLexerKind.multiplication
	elsif character = '=' then
		result := ElnaLexerKind.equals
	elsif character = '%' then
		result := ElnaLexerKind.remainder
	elsif character = '/' then
		result := ElnaLexerKind.division
	elsif character = '.' then
		result := ElnaLexerKind.dot
	elsif character = '^' then
		result := ElnaLexerKind.hat
	elsif character = '[' then
		result := ElnaLexerKind.left_square
	elsif character = ']' then
		result := ElnaLexerKind.right_square
	end;
	return result
end;

proc _elna_lexer_classify_composite(start_position: Word, one_before_last: Word);
var
	first_character: Word;
	last_character: Word;
	result: Word;
begin
	first_character := _load_byte(start_position);
	last_character := _load_byte(one_before_last);

	if first_character = ':' then
		result := ElnaLexerKind.assignment
	elsif first_character = '<' then
		if last_character = '=' then
			result := ElnaLexerKind.less_equal
		elsif last_character = '>' then
			result := ElnaLexerKind.not_equal
		end
	elsif first_character = '>' then
		if last_character = '=' then
			result := ElnaLexerKind.greater_equal
		end
	end;

	return result
end;

proc _elna_lexer_classify_delimited(start_position: Word, end_position: Word);
var
	token_length: Word;
	delimiter: Word;
	result: Word;
begin
	token_length := end_position - start_position;
	delimiter := _load_byte(start_position);

	if delimiter = '(' then
		result := ElnaLexerKind.comment
	elsif delimiter = '\'' then
		result := ElnaLexerKind.character
	elsif delimiter = '"' then
		result := ElnaLexerKind.string
	end;
	return result
end;

proc _elna_lexer_classify_integer(start_position: Word, end_position: Word);
	return ElnaLexerKind.integer
end;

proc _elna_lexer_execute_action(action_to_perform: Word, kind: Word);
var
	position_start: Word;
	position_end: Word;
	intermediate: Word;
begin
	position_start := _elna_lexer_global_get_start();
	position_end := _elna_lexer_global_get_end();

	if action_to_perform = ElnaLexerAction.none then
	elsif action_to_perform = ElnaLexerAction.accumulate then
		_elna_lexer_global_set_end(position_end + 1)
	elsif action_to_perform = ElnaLexerAction.skip then
		_elna_lexer_global_set_start(position_start + 1);
		_elna_lexer_global_set_end(position_end + 1)
	elsif action_to_perform = ElnaLexerAction.single then
		_elna_lexer_global_set_end(position_end + 1);

		intermediate := _elna_lexer_classify_single(position_start);
		kind^ := intermediate
	elsif action_to_perform = ElnaLexerAction.eof then
		intermediate := ElnaLexerKind.eof;
		kind^ := intermediate
	elsif action_to_perform = ElnaLexerAction.finalize then
		intermediate := _elna_lexer_classify_finalize(position_start);
		kind^ := intermediate
	elsif action_to_perform = ElnaLexerAction.composite then
		_elna_lexer_global_set_end(position_end + 1);

		intermediate := _elna_lexer_classify_composite(position_start, position_end);
		kind^ := intermediate
	elsif action_to_perform = ElnaLexerAction.key_id then
		intermediate := _elna_lexer_classify_keyword(position_start, position_end);
		kind^ := intermediate
	elsif action_to_perform = ElnaLexerAction.integer then
		intermediate := _elna_lexer_classify_integer(position_start, position_end);
		kind^ := intermediate
	elsif action_to_perform = ElnaLexerAction.delimited then
		_elna_lexer_global_set_end(position_end + 1);

		intermediate := _elna_lexer_classify_delimited(position_start, position_end + 1);
		kind^ := intermediate
	end
end;

proc _elna_lexer_execute_transition(kind: Word);
var
	next_transition: Word;
	next_state: Word;
	global_state: Word;
	action_to_perform: Word;
begin
	next_transition := _elna_lexer_next_transition();
	next_state := _elna_lexer_transition_get_state(next_transition);
	action_to_perform := _elna_lexer_transition_get_action(next_transition);

	global_state := _elna_lexer_global_state();

	global_state^ := next_state;
	_elna_lexer_execute_action(action_to_perform, kind);

	return next_state
end;

proc _elna_lexer_advance_token(kind: Word);
var
	result_state: Word;
begin
	result_state := _elna_lexer_execute_transition(kind);
	if result_state <> ElnaLexerState.finish then
		_elna_lexer_advance_token(kind)
	end
end;

(**
 * Reads the next token and writes its type into the address in the kind parameter.
 *)
proc _elna_lexer_read_token(kind: Word);
begin
	_elna_lexer_reset();
	_elna_lexer_advance_token(kind)
end;

(**
 * Advances the token stream past the last read token.
 *)
proc _elna_lexer_skip_token();
var
	old_end: Word;
begin
	old_end := _elna_lexer_global_get_end();
	_elna_lexer_global_set_start(old_end)
end;

proc _initialize_global_state();
begin
	compiler_strings_position := @compiler_strings;
	source_code := malloc(495616);
	symbol_table_store := malloc(4194304);
end;

(*
 * Entry point.
 *)
proc main();
var
	last_read: Word;
	offset: Word;
begin
	_initialize_global_state();
	_elna_lexer_initialize(source_code);
	_symbol_table_build();

	(* Read the source from the standard input. *)
	offset := source_code;

	.start_read;
	(* Second argument is buffer size. Modifying update the source_code definition. *)
	last_read := read(0, offset, 409600);
	if last_read > 0 then
		offset := offset + last_read;
		goto start_read
	end;
	if _compile() then
		exit(0)
	else
		exit(4)
	end;
end;