diff options
Diffstat (limited to 'boot')
| -rw-r--r-- | boot/stage19/cl.elna | 93 | ||||
| -rw-r--r-- | boot/stage20/cl.elna | 5309 | ||||
| -rw-r--r-- | boot/stage20/linker.arg | 0 |
3 files changed, 5358 insertions, 44 deletions
diff --git a/boot/stage19/cl.elna b/boot/stage19/cl.elna index 2fd12a0..76ee09b 100644 --- a/boot/stage19/cl.elna +++ b/boot/stage19/cl.elna @@ -252,7 +252,8 @@ type length: Word; body: Word; temporaries: Word; - parameters: Word + parameters: Word; + return_type: ^ElnaTreeNode end; ElnaTreeTypeDeclaration = record kind: ElnaTreeKind; @@ -528,7 +529,7 @@ type allocate_stack, ret ); - ElnaRtlKind = (register, immediate, symbol, pseudo, offset, pseudo_mem); + ElnaRtlKind = (register, immediate, symbol, pseudo, offset); ElnaRtlOperand = record kind: ElnaRtlKind; value: Word; @@ -1008,17 +1009,15 @@ begin return result end; -proc elna_rtl_call(tac_instruction: ^ElnaTacInstruction, next_instruction: ^^ElnaRtlInstruction); +proc elna_rtl_call(tac_instruction: ^ElnaTacInstruction, next_instruction: ^^ElnaRtlInstruction, variable_map: ^ElnaSymbolTable); var argument_count: Word; current_argument: ^ElnaTacOperand; - argument_type: Word; - argument_value: Word; - argument_length: Word; argument_move: ^ElnaRtlInstruction; current_register: Word; first_instruction: Word; current_instruction: Word; + variable_info: ^ElnaRtlInfo; begin current_register := 0; first_instruction := nil; @@ -1031,15 +1030,12 @@ begin if argument_count > 0 then argument_count := argument_count - 1; - argument_type := current_argument^.kind; - argument_value := current_argument^.value; - argument_length := current_argument^.length; - current_argument := current_argument + #size(ElnaTacOperand); - - argument_move := elna_rtl_instruction_create(ElnaRtlOperator.move); - elna_rtl_instruction_set_operand(argument_move, 1, ElnaRtlKind.register, ElnaRtlRegister.a0 + current_register, 0); - elna_rtl_instruction_set_operand(argument_move, 2, argument_type, argument_value, argument_length); - + if current_argument^.kind = ElnaTacKind.pseudo then + argument_move := elna_rtl_instruction_create(ElnaRtlOperator.move); + elna_rtl_instruction_set_operand(argument_move, 1, ElnaRtlKind.register, ElnaRtlRegister.a0 + current_register, 0); + elna_rtl_instruction_set_operand(argument_move, 2, ElnaRtlKind.pseudo, + current_argument^.value, current_argument^.length) + end; if first_instruction = nil then first_instruction := argument_move else @@ -1047,6 +1043,7 @@ begin end; current_instruction := argument_move; + current_argument := current_argument + #size(ElnaTacOperand); current_register := current_register + 1; goto elna_rtl_call_loop @@ -1119,7 +1116,7 @@ begin return result end; -proc elna_rtl_instruction(tac_instruction: ^ElnaTacInstruction, next_instruction: ^^ElnaRtlInstruction); +proc elna_rtl_instruction(tac_instruction: ^ElnaTacInstruction, next_instruction: ^^ElnaRtlInstruction, variable_map: ^ElnaSymbolTable); var result: ^ElnaRtlInstruction; operands: ^ElnaRtlInstruction; @@ -1140,7 +1137,7 @@ begin elsif tac_instruction^.operator = ElnaTacOperator.store then result := elna_rtl_store(tac_instruction, next_instruction) elsif tac_instruction^.operator = ElnaTacOperator.proc_call then - result := elna_rtl_call(tac_instruction, next_instruction) + result := elna_rtl_call(tac_instruction, next_instruction, variable_map) elsif tac_instruction^.operator = ElnaTacOperator.subtract then result := elna_rtl_binary_arithmetic(tac_instruction, next_instruction, ElnaRtlOperator.sub) elsif tac_instruction^.operator = ElnaTacOperator.multiply then @@ -1591,7 +1588,7 @@ begin _write_c('\n') end; -proc elna_rtl_instructions(instruction: ^ElnaTacInstruction); +proc elna_rtl_instructions(instruction: ^ElnaTacInstruction, variable_map: ^ElnaSymbolTable); var last_copy: ^ElnaRtlInstruction; current_copy: ^ElnaRtlInstruction; @@ -1599,7 +1596,7 @@ var first_copy: ^ElnaRtlInstruction; begin if instruction <> nil then - first_copy := elna_rtl_instruction(instruction, @current_copy); + first_copy := elna_rtl_instruction(instruction, @current_copy, variable_map); instruction := instruction^.next else first_copy := nil; @@ -1608,7 +1605,7 @@ begin .elna_rtl_instructions_start; if instruction <> nil then - next_copy := elna_rtl_instruction(instruction, @last_copy); + next_copy := elna_rtl_instruction(instruction, @last_copy, variable_map); instruction := instruction^.next; current_copy^.next := next_copy; @@ -2874,10 +2871,10 @@ begin elna_tac_instruction_set_operand(current_instruction, 1, operand_type, operand_value, operand_length); elna_tac_instruction_set_operand(current_instruction, 2, ElnaTacKind.symbol, condition_label, 0); - elna_instruction_list_concatenate(first_instruction, current_instruction); + first_instruction := elna_instruction_list_concatenate(first_instruction, current_instruction); instruction := elna_tac_statements(parser_node^.statements, symbol_table); - if instruction <> 0 then + if instruction <> nil then elna_instruction_list_concatenate(current_instruction, instruction); current_instruction := instruction end; @@ -3563,10 +3560,16 @@ begin _elna_lexer_skip_token(); result^.parameters := parameter_head; - (* Skip semicolon and newline. *) + (* Skip semicolon or arrow. *) _elna_lexer_read_token(@token_kind); _elna_lexer_skip_token(); + if token_kind = ElnaLexerKind.arrow then + result^.return_type := elna_parser_type_expression() + else + result^.return_type := nil + end; + parameter_head := elna_parser_var_part(); result^.temporaries := parameter_head; @@ -3713,17 +3716,17 @@ begin pseudo_symbol^.allocated := false; if elna_type_is_aggregate(variable_info^.variable_type) then - long_word := malloc(#size(ElnaRtlTypeWord)); - long_word^.kind := ElnaRtlTypeKind.long_word; - long_word^.size := variable_info^.variable_type^.size; - - pseudo_symbol^.rtl_type = long_word - else byte_array := malloc(#size(ElnaRtlTypeByteArray)); byte_array^.kind := ElnaRtlTypeKind.byte_array; byte_array^.size := variable_info^.variable_type^.size; - pseudo_symbol^.rtl_type = byte_array + pseudo_symbol^.rtl_type := byte_array + else + long_word := malloc(#size(ElnaRtlTypeWord)); + long_word^.kind := ElnaRtlTypeKind.long_word; + long_word^.size := variable_info^.variable_type^.size; + + pseudo_symbol^.rtl_type := long_word end; elna_symbol_table_enter(variable_map, current_entry^.name, current_entry^.length, pseudo_symbol); @@ -3749,9 +3752,9 @@ begin result^.length := tac_declaration^.length; 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); result^.variable_map := elna_rtl_symbol_table(tac_declaration^.symbol_table); + body := elna_rtl_instructions(tac_declaration^.body, result^.variable_map); + result^.body := elna_instruction_list_concatenate(parameters, body); return result end; @@ -5039,7 +5042,7 @@ begin return result end; -proc _elna_lexer_classify_keyword(position_start: Word, position_end: Word); +proc elna_lexer_classify_keyword(position_start: Word, position_end: Word); var result: Word; token_length: Word; @@ -5095,7 +5098,7 @@ begin return result end; -proc _elna_lexer_classify_finalize(start_position: Word); +proc elna_lexer_classify_finalize(start_position: Word); var character: Word; result: Word; @@ -5119,7 +5122,7 @@ begin return result end; -proc _elna_lexer_classify_single(start_position: Word); +proc elna_lexer_classify_single(start_position: Word); var character: Word; result: Word; @@ -5161,7 +5164,7 @@ begin return result end; -proc _elna_lexer_classify_composite(start_position: Word, one_before_last: Word); +proc elna_lexer_classify_composite(start_position: Word, one_before_last: Word); var first_character: Word; last_character: Word; @@ -5182,12 +5185,14 @@ begin if last_character = '=' then result := ElnaLexerKind.greater_equal end + elsif first_character = '-' then + result := ElnaLexerKind.arrow end; return result end; -proc _elna_lexer_classify_delimited(start_position: Word, end_position: Word); +proc elna_lexer_classify_delimited(start_position: Word, end_position: Word); var token_length: Word; delimiter: Word; @@ -5206,7 +5211,7 @@ begin return result end; -proc _elna_lexer_classify_integer(start_position: Word, end_position: Word); +proc elna_lexer_classify_integer(start_position: Word, end_position: Word); return ElnaLexerKind.integer end; @@ -5223,29 +5228,29 @@ begin elsif action_to_perform = ElnaLexerAction.single then lexer_state.finish := lexer_state.finish + 1; - intermediate := _elna_lexer_classify_single(lexer_state.start); + intermediate := elna_lexer_classify_single(lexer_state.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(lexer_state.start); + intermediate := elna_lexer_classify_finalize(lexer_state.start); kind^ := intermediate elsif action_to_perform = ElnaLexerAction.composite then - intermediate := _elna_lexer_classify_composite(lexer_state.start, lexer_state.finish); + intermediate := elna_lexer_classify_composite(lexer_state.start, lexer_state.finish); kind^ := intermediate; lexer_state.finish := lexer_state.finish + 1 elsif action_to_perform = ElnaLexerAction.key_id then - intermediate := _elna_lexer_classify_keyword(lexer_state.start, lexer_state.finish); + intermediate := elna_lexer_classify_keyword(lexer_state.start, lexer_state.finish); kind^ := intermediate elsif action_to_perform = ElnaLexerAction.integer then - intermediate := _elna_lexer_classify_integer(lexer_state.start, lexer_state.finish); + intermediate := elna_lexer_classify_integer(lexer_state.start, lexer_state.finish); kind^ := intermediate elsif action_to_perform = ElnaLexerAction.delimited then lexer_state.finish := lexer_state.finish + 1; - intermediate := _elna_lexer_classify_delimited(lexer_state.start, lexer_state.finish); + intermediate := elna_lexer_classify_delimited(lexer_state.start, lexer_state.finish); kind^ := intermediate end end; diff --git a/boot/stage20/cl.elna b/boot/stage20/cl.elna new file mode 100644 index 0000000..08d6b6c --- /dev/null +++ b/boot/stage20/cl.elna @@ -0,0 +1,5309 @@ +(* + * 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 20 compiler. *) + +type + (** + * List of intermediate representation items. + *) + ElnaInstructionList = record + next: Word + end; + ElnaInstructionModule = record + data: Word; + code: 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, + array_access_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; + ElnaTreeArrayAccessExpression = record + kind: ElnaTreeKind; + type_decoration: ^ElnaType; + array: Word; + index: 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; + return_type: ^ElnaTreeNode + 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; + ElnaTreeExpressionList = record + expression: ^ElnaTreeBinaryExpression; + next: Word + end; + ElnaTreeCall = record + kind: ElnaTreeKind; + next: Word; + callee: ^ElnaTreeVariableExpression; + arguments: ^ElnaTreeExpressionList; + count: Word + end; + + (* Symbol table information. *) + ElnaSymbolEntry = record + name: Word; + length: Word; + symbol_info: Word + end; + ElnaSymbolTable = record + count: Word; + symbols: ^ElnaSymbolEntry + end; + ElnaSymbolInfoKind = (type_info, parameter_info, temporary_info, procedure_info); + ElnaSymbolInfo = record + kind: ElnaSymbolInfoKind + end; + ElnaSymbolTypeInfo = record + kind: ElnaSymbolInfoKind; + _type: ^ElnaType + end; + (* ElnaSymbolTemporaryInfo.offset is 0 or 1, 0: local variable, 1: pseudo register *) + ElnaSymbolTemporaryInfo = record + kind: ElnaSymbolInfoKind; + attr: Word; + variable_type: ^ElnaType + end; + ElnaSymbolProcedureInfo = record + kind: ElnaSymbolInfoKind; + symbol_table: ^ElnaSymbolTable + 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); + + ElnaLexerTransition = record + action: ElnaLexerAction; + next_state: Word + end; + (** + * Classification table assigns each possible character to a group (class). All + * characters of the same group a handled equivalently. + *) + 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 + ); + ElnaLexerCursor = record + state: ElnaLexerState; + start: Word; + finish: Word + end; + + 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 + ); + ElnaTacKind = (list, immediate, symbol, pseudo); + ElnaTacOperand = record + kind: ElnaTacKind; + value: Word; + length: Word; + offset: Word + end; + ElnaTacInstruction = record + next: Word; + operator: ElnaTacOperator; + operands: [3]ElnaTacOperand + end; + ElnaTacProcedure = record + next: Word; + name: Word; + length: Word; + body: Word; + parameters: Word; + count: Word; + symbol_table: ^ElnaSymbolTable + end; + ElnaTacStaticVariable = record + next: Word; + name: Word; + length: Word; + body: Word + end; + + 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 + ); + ElnaRtlKind = (register, immediate, symbol, pseudo, offset, pseudo_mem); + ElnaRtlOperand = record + kind: ElnaRtlKind; + value: Word; + length: Word; + offset: Word + end; + ElnaRtlStaticVariable = record + next: Word; + name: Word; + length: Word; + body: Word + end; + ElnaRtlProcedure = record + next: Word; + name: Word; + length: Word; + body: Word; + variable_map: ^ElnaSymbolTable + end; + ElnaRtlInstruction = record + next: Word; + operator: ElnaRtlOperator; + operands: [3]ElnaRtlOperand + end; + 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 + ); + ElnaRtlTypeKind = (long_word, byte_array); + ElnaRtlType = record + kind: ElnaRtlTypeKind; + size: Word + end; + ElnaRtlTypeWord = record + kind: ElnaRtlTypeKind; + size: Word + end; + ElnaRtlTypeByteArray = record + kind: ElnaRtlTypeKind; + size: Word + end; + ElnaRtlInfo = record + counter: Word; + rtl_type: ^ElnaRtlType; + allocated: Word + end; + +var + symbol_table_global: [1024]Word; + compiler_strings: [1024]Word; + + classification: [256]Word; + (** + * 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. + *) + transition_table: [19][23]ElnaLexerTransition; + lexer_state: ElnaLexerCursor; + + word_type: ^ElnaType; + + source_code: Word; + compiler_strings_position: Word; + compiler_strings_length: Word; + label_counter: Word; + temporary_variable_counter: Word; + pseudo_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 + counter: Word; + current_byte: Word; +begin + (* Reset the counter. *) + counter := 0; + + .string_length_loop; + string := string + 1; + + current_byte := _load_byte(string); + if current_byte <> '"' then + counter := counter + 1; + goto string_length_loop + end; + + return counter +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 + contents: Word; + result: Word; + current_byte: Word; +begin + contents := string + 1; + result := compiler_strings_length; + + .add_string_loop; + current_byte := _load_byte(contents); + if current_byte <> '"' then + _store_byte(current_byte, compiler_strings_position); + compiler_strings_position := compiler_strings_position + 1; + contents := contents + 1; + + if current_byte <> '\\' then + compiler_strings_length := compiler_strings_length + 1 + end; + goto add_string_loop + end; + + return result +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_underscore: Word; +begin + is_underscore := character = '_'; + + return isalpha(character) or is_underscore +end; + +proc _is_alnum(character: Word); + return _is_alpha(character) or isdigit(character) +end; + +proc elna_tac_generate_pseudo(operand_type: Word, operand_value: Word, operand_length: Word, symbol_table: ^ElnaSymbolTable); +var + buffer: Word; + temporary_info: ^ElnaSymbolTemporaryInfo; +begin + pseudo_counter := pseudo_counter + 1; + buffer := malloc(6); + + sprintf(buffer, "$%i\0", pseudo_counter); + + operand_type^ := ElnaTacKind.pseudo; + operand_value^ := buffer; + operand_length^ := strlen(buffer); + + temporary_info := _temporary_info_create(1, word_type); + elna_symbol_table_enter(symbol_table, buffer, operand_length^, temporary_info) +end; + +proc elna_instruction_list_concatenate(this: ^ElnaInstructionList, value: Word); +var + start: Word; +begin + if this = 0 then + start := value; + goto elna_instruction_list_concatenate_end + else + start := 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 start +end; + +proc elna_tac_instruction_set_operand(this: ^ElnaTacInstruction, n: Word, operand_type: Word, operand_value: Word, operand_length: Word); +begin + this^.operands[n].kind := operand_type; + this^.operands[n].value := operand_value; + this^.operands[n].length := operand_length +end; + +proc elna_tac_instruction_create(kind: Word); +var + result: ^ElnaTacInstruction; +begin + result := malloc(#size(ElnaTacInstruction)); + + result^.operator := kind; + elna_instruction_list_concatenate(result, nil); + + return result +end; + +proc elna_rtl_instruction_create(kind: Word); +var + result: ^ElnaRtlInstruction; +begin + result := malloc(#size(ElnaRtlInstruction)); + + result^.operator := kind; + result^.next := nil; + + return result +end; + +proc elna_rtl_instruction_set_operand(this: ^ElnaRtlInstruction, n: Word, operand_type: Word, operand_value: Word, operand_length: Word); +begin + this^.operands[n].kind := operand_type; + this^.operands[n].value := operand_value; + this^.operands[n].length := operand_length +end; + +proc elna_rtl_load_operand_value(tac_instruction: ^ElnaTacInstruction, operand_number: Word, into: Word); +var + result: ^ElnaRtlInstruction; + operand_value: Word; + operand_length: Word; + operand_type: Word; + next_instruction: Word; +begin + operand_type := tac_instruction^.operands[operand_number].kind; + operand_value := tac_instruction^.operands[operand_number].value; + operand_length := tac_instruction^.operands[operand_number].length; + + if operand_type = ElnaTacKind.immediate then + result := elna_rtl_instruction_create(ElnaRtlOperator.li); + elna_rtl_instruction_set_operand(result, 1, ElnaRtlKind.register, into, 0); + elna_rtl_instruction_set_operand(result, 2, ElnaRtlKind.immediate, operand_value, operand_length) + elsif operand_type = ElnaTacKind.symbol then + result := elna_rtl_instruction_create(ElnaRtlOperator.la); + elna_rtl_instruction_set_operand(result, 1, ElnaRtlKind.register, into, 0); + elna_rtl_instruction_set_operand(result, 2, ElnaRtlKind.symbol, operand_value, operand_length); + + next_instruction := elna_rtl_instruction_create(ElnaRtlOperator.lw); + elna_rtl_instruction_set_operand(next_instruction, 1, ElnaRtlKind.register, into, 0); + elna_rtl_instruction_set_operand(next_instruction, 2, ElnaRtlKind.offset, into, 0); + + result^.next := next_instruction + elsif operand_type = ElnaTacKind.pseudo then + result := elna_rtl_instruction_create(ElnaRtlOperator.move); + elna_rtl_instruction_set_operand(result, 1, ElnaRtlKind.register, into, 0); + elna_rtl_instruction_set_operand(result, 2, ElnaRtlKind.pseudo, operand_value, operand_length) + end; + + return result +end; + +proc elna_rtl_load_operand_address(tac_instruction: ^ElnaTacInstruction, operand_number: Word, into: Word); +var + result: Word; + operand_value: Word; + operand_length: Word; + operand_type: Word; +begin + operand_type := tac_instruction^.operands[operand_number].kind; + operand_value := tac_instruction^.operands[operand_number].value; + operand_length := tac_instruction^.operands[operand_number].length; + + if operand_type = ElnaTacKind.symbol then + result := elna_rtl_instruction_create(ElnaRtlOperator.la); + elna_rtl_instruction_set_operand(result, 1, ElnaRtlKind.register, into, 0); + elna_rtl_instruction_set_operand(result, 2, ElnaRtlKind.symbol, operand_value, operand_length) + elsif operand_type = ElnaTacKind.pseudo then + result := elna_rtl_instruction_create(ElnaRtlOperator.la); + elna_rtl_instruction_set_operand(result, 1, ElnaRtlKind.register, into, 0); + elna_rtl_instruction_set_operand(result, 2, ElnaRtlKind.pseudo, operand_value, operand_length) + end; + + return result +end; + +proc elna_rtl_binary_operands(tac_instruction: ^ElnaTacInstruction, next_instruction: ^^ElnaRtlInstruction); +var + lhs: ^ElnaRtlInstruction; + rhs: ^ElnaRtlInstruction; +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: ^ElnaTacInstruction, next_instruction: ^^ElnaRtlInstruction, operation: Word); +var + lhs: Word; + binary_result: ^ElnaRtlInstruction; + intermediate_instruction: ^ElnaRtlInstruction; +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, ElnaRtlKind.register, ElnaRtlRegister.t2, 0); + elna_rtl_instruction_set_operand(binary_result, 3, ElnaRtlKind.register, ElnaRtlRegister.t3, 0); + binary_result^.operator := operation; + + intermediate_instruction := next_instruction^; + intermediate_instruction^.next := binary_result; + next_instruction^ := binary_result; + + return lhs +end; + +proc elna_rtl_binary_equality(tac_instruction: ^ElnaTacInstruction, instruction_kind: Word, next_instruction: ^^ElnaRtlInstruction); +var + operands: ^ElnaRtlInstruction; + intermediate_instruction: ^ElnaRtlInstruction; + operating_instruction: ^ElnaRtlInstruction; + binary_result: ^ElnaRtlInstruction; +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, ElnaRtlKind.register, ElnaRtlRegister.t2, 0); + elna_rtl_instruction_set_operand(operating_instruction, 2, ElnaRtlKind.register, ElnaRtlRegister.t2, 0); + elna_rtl_instruction_set_operand(operating_instruction, 3, ElnaRtlKind.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, ElnaRtlKind.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: ^ElnaTacInstruction, number: Word, rtl_instruction: Word); +var + operand_length: Word; + operand_type: Word; + operand_value: Word; +begin + operand_type := tac_instruction^.operands[number].kind; + operand_value := tac_instruction^.operands[number].value; + operand_length := tac_instruction^.operands[number].length; + + if operand_type = ElnaTacKind.immediate then + elna_rtl_instruction_set_operand(rtl_instruction, number, ElnaRtlKind.immediate, operand_value, operand_length) + elsif operand_type = ElnaTacKind.symbol then + elna_rtl_instruction_set_operand(rtl_instruction, number, ElnaRtlKind.symbol, operand_value, operand_length) + elsif operand_type = ElnaTacKind.pseudo then + elna_rtl_instruction_set_operand(rtl_instruction, number, ElnaRtlKind.pseudo, operand_value, operand_length) + end +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: ^ElnaRtlInstruction; +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, ElnaRtlKind.register, ElnaRtlRegister.t0); + result^.next := next_instruction^; + + return result +end; + +proc elna_rtl_call(tac_instruction: ^ElnaTacInstruction, next_instruction: ^^ElnaRtlInstruction, variable_map: ^ElnaSymbolTable); +var + argument_count: Word; + current_argument: ^ElnaTacOperand; + argument_move: ^ElnaRtlInstruction; + current_register: Word; + first_instruction: Word; + current_instruction: Word; + variable_info: ^ElnaRtlInfo; +begin + current_register := 0; + first_instruction := nil; + + current_argument := tac_instruction^.operands[2].value; + argument_count := tac_instruction^.operands[2].length; + + .elna_rtl_call_loop; + + if argument_count > 0 then + argument_count := argument_count - 1; + + if current_argument^.kind = ElnaTacKind.pseudo then + variable_info := elna_symbol_table_lookup(variable_map, current_argument^.value, current_argument^.length); + (* DEBUG printf("# Sample %i %.*s\n\0", variable_info^.rtl_type^.size, current_argument^.length, current_argument^.value); *) + + if variable_info^.rtl_type^.size <= 4 then + argument_move := elna_rtl_instruction_create(ElnaRtlOperator.move); + elna_rtl_instruction_set_operand(argument_move, 1, ElnaRtlKind.register, ElnaRtlRegister.a0 + current_register, 0); + elna_rtl_instruction_set_operand(argument_move, 2, ElnaRtlKind.pseudo, + current_argument^.value, current_argument^.length) + elsif variable_info^.rtl_type^.size <= 8 then + + argument_move := elna_rtl_instruction_create(ElnaRtlOperator.move); + elna_rtl_instruction_set_operand(argument_move, 1, ElnaRtlKind.register, ElnaRtlRegister.a0 + current_register, 0); + elna_rtl_instruction_set_operand(argument_move, 2, ElnaRtlKind.pseudo, + current_argument^.value, current_argument^.length) + end + end; + if first_instruction = nil then + first_instruction := argument_move + else + elna_instruction_list_concatenate(current_instruction, argument_move) + end; + current_instruction := argument_move; + + current_argument := current_argument + #size(ElnaTacOperand); + 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_move := elna_rtl_instruction_create(ElnaRtlOperator.move); + elna_rtl_instruction_set_operand(argument_move, 1, tac_instruction^.operands[3].kind, + tac_instruction^.operands[3].value, tac_instruction^.operands[3].length); + elna_rtl_instruction_set_operand(argument_move, 2, ElnaRtlKind.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: ^ElnaTacInstruction, next_instruction: ^^ElnaRtlInstruction); +var + result: ^ElnaRtlInstruction; + operands: ^ElnaRtlInstruction; +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, ElnaRtlKind.register, ElnaRtlRegister.t0, 0); + + if tac_instruction^.operands[2].kind = ElnaTacKind.pseudo then + elna_rtl_instruction_set_operand(next_instruction^, 2, ElnaRtlKind.pseudo, + tac_instruction^.operands[2].value, tac_instruction^.operands[2].length) + end; + if operands = nil then + result^.next := next_instruction^ + else + operands^.next := next_instruction^ + end; + return result +end; + +proc elna_rtl_load(tac_instruction: ^ElnaTacInstruction, next_instruction: ^^ElnaRtlInstruction); +var + result: ^ElnaRtlInstruction; + operands: ^ElnaRtlInstruction; +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, ElnaRtlKind.offset, ElnaRtlRegister.t0, 0); + + elna_rtl_instruction_set_operand(next_instruction^, 1, tac_instruction^.operands[2].kind, + tac_instruction^.operands[2].value, tac_instruction^.operands[2].length); + + if operands = 0 then + result^.next := next_instruction^ + else + operands^.next := next_instruction^ + end; + return result +end; + +proc elna_rtl_instruction(tac_instruction: ^ElnaTacInstruction, next_instruction: ^^ElnaRtlInstruction, variable_map: ^ElnaSymbolTable); +var + result: ^ElnaRtlInstruction; + operands: ^ElnaRtlInstruction; + intermediate_instruction: ^ElnaRtlInstruction; +begin + result := malloc(#size(ElnaRtlInstruction)); + next_instruction^ := nil; + + if tac_instruction^.operator = 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 tac_instruction^.operator = ElnaTacOperator.add then + result := elna_rtl_binary_arithmetic(tac_instruction, next_instruction, ElnaRtlOperator.add) + elsif tac_instruction^.operator = ElnaTacOperator.load then + result := elna_rtl_load(tac_instruction, next_instruction) + elsif tac_instruction^.operator = ElnaTacOperator.store then + result := elna_rtl_store(tac_instruction, next_instruction) + elsif tac_instruction^.operator = ElnaTacOperator.proc_call then + result := elna_rtl_call(tac_instruction, next_instruction, variable_map) + elsif tac_instruction^.operator = ElnaTacOperator.subtract then + result := elna_rtl_binary_arithmetic(tac_instruction, next_instruction, ElnaRtlOperator.sub) + elsif tac_instruction^.operator = ElnaTacOperator.multiply then + result := elna_rtl_binary_arithmetic(tac_instruction, next_instruction, ElnaRtlOperator.mul) + elsif tac_instruction^.operator = ElnaTacOperator.divide then + result := elna_rtl_binary_arithmetic(tac_instruction, next_instruction, ElnaRtlOperator.div) + elsif tac_instruction^.operator = ElnaTacOperator.remainder then + result := elna_rtl_binary_arithmetic(tac_instruction, next_instruction, ElnaRtlOperator.rem) + elsif tac_instruction^.operator = ElnaTacOperator._xor then + result := elna_rtl_binary_arithmetic(tac_instruction, next_instruction, ElnaRtlOperator._xor) + elsif tac_instruction^.operator = ElnaTacOperator._or then + result := elna_rtl_binary_arithmetic(tac_instruction, next_instruction, ElnaRtlOperator._or) + elsif tac_instruction^.operator = ElnaTacOperator.and then + result := elna_rtl_binary_arithmetic(tac_instruction, next_instruction, ElnaRtlOperator.and) + elsif tac_instruction^.operator = ElnaTacOperator.less_than then + result := elna_rtl_binary_arithmetic(tac_instruction, next_instruction, ElnaRtlOperator.slt) + elsif tac_instruction^.operator = 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, ElnaRtlKind.register, ElnaRtlRegister.t3, 0); + elna_rtl_instruction_set_operand(result, 3, ElnaRtlKind.register, ElnaRtlRegister.t2, 0); + + intermediate_instruction := next_instruction^; + intermediate_instruction^.next := result; + next_instruction^ := result; + + result := operands; + next_instruction^^.operator := ElnaRtlOperator.slt + elsif tac_instruction^.operator = 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, ElnaRtlKind.register, ElnaRtlRegister.t2, 0); + elna_rtl_instruction_set_operand(intermediate_instruction, 2, ElnaRtlKind.register, ElnaRtlRegister.t3, 0); + elna_rtl_instruction_set_operand(intermediate_instruction, 3, ElnaRtlKind.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, ElnaRtlKind.register, ElnaRtlRegister.t2, 0); + elna_rtl_instruction_set_operand(result, 3, ElnaRtlKind.immediate, 1, 0); + intermediate_instruction := next_instruction^; + intermediate_instruction^.next := result; + next_instruction^ := result; + result := operands + elsif tac_instruction^.operator = 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, ElnaRtlKind.register, ElnaRtlRegister.t2, 0); + elna_rtl_instruction_set_operand(intermediate_instruction, 2, ElnaRtlKind.register, ElnaRtlRegister.t2, 0); + elna_rtl_instruction_set_operand(intermediate_instruction, 3, ElnaRtlKind.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, ElnaRtlKind.register, ElnaRtlRegister.t2, 0); + elna_rtl_instruction_set_operand(result, 3, ElnaRtlKind.immediate, 1, 0); + intermediate_instruction := next_instruction^; + intermediate_instruction^.next := result; + next_instruction^ := result; + result := operands + elsif tac_instruction^.operator = ElnaTacOperator.equal then + result := elna_rtl_binary_equality(tac_instruction, ElnaRtlOperator.seqz, next_instruction) + elsif tac_instruction^.operator = ElnaTacOperator.not_equal then + result := elna_rtl_binary_equality(tac_instruction, ElnaRtlOperator.snez, next_instruction) + elsif tac_instruction^.operator = ElnaTacOperator.negate then + result := elna_rtl_unary(tac_instruction, ElnaRtlOperator.neg, next_instruction) + elsif tac_instruction^.operator = ElnaTacOperator.complement then + result := elna_rtl_unary(tac_instruction, ElnaRtlOperator.not, next_instruction) + elsif tac_instruction^.operator = ElnaTacOperator.jump then + result := elna_rtl_instruction_create(ElnaRtlOperator.j); + elna_rtl_copy_operand(tac_instruction, 1, result) + elsif tac_instruction^.operator = ElnaTacOperator.jump_if_zero then + result := elna_rtl_conditional_jump(tac_instruction, ElnaRtlOperator.beqz) + elsif tac_instruction^.operator = ElnaTacOperator.jump_if_not_zero then + result := elna_rtl_conditional_jump(tac_instruction, ElnaRtlOperator.bnez) + elsif tac_instruction^.operator = ElnaTacOperator._return then + result := elna_rtl_load_operand_value(tac_instruction, 1, ElnaRtlRegister.a0) + elsif tac_instruction^.operator = ElnaTacOperator.label then + result := elna_rtl_instruction_create(ElnaRtlOperator.label); + elna_rtl_copy_operand(tac_instruction, 1, result) + elsif tac_instruction^.operator = ElnaTacOperator.copy then + if tac_instruction^.operands[1].kind = ElnaTacKind.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, ElnaRtlKind.pseudo, + tac_instruction^.operands[1].value, tac_instruction^.operands[1].length); + elna_tac_instruction_set_operand(next_instruction^, 2, ElnaRtlKind.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_tac_label(counter: Word, length: Word); +var + result: Word; +begin + result := elna_tac_instruction_create(ElnaTacOperator.label); + + elna_tac_instruction_set_operand(result, 1, ElnaTacKind.symbol, counter, length); + + return result +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 + printf("x%i\0", register - 1); + fflush(nil) +end; + +proc elna_riscv_operand(instruction: ^ElnaRtlInstruction, n: Word); +var + operand_type: Word; +begin + operand_type := instruction^.operands[n].kind; + + _write_c(' '); + if operand_type = ElnaRtlKind.register then + elna_riscv_register(instruction^.operands[n].value) + elsif operand_type = ElnaRtlKind.offset then + _write_i(instruction^.operands[n].length); + _write_c('('); + elna_riscv_register(instruction^.operands[n].value); + _write_c(')') + elsif operand_type = ElnaRtlKind.symbol then + if instruction^.operands[n].length = 0 then + _write_label(instruction^.operands[n].value, 0) + else + _write_s(instruction^.operands[n].value, instruction^.operands[n].length) + end + elsif instruction^.operands[n].length = 0 then (* ElnaRtlKind.immediate *) + _write_i(instruction^.operands[n].value) + else + _write_s(instruction^.operands[n].value, instruction^.operands[n].length) + end +end; + +proc elna_alloc_variable(operand_value: Word, operand_length: Word, variable_map: ^ElnaSymbolTable); +var + pseudo_symbol: ^ElnaRtlInfo; +begin + pseudo_symbol := elna_symbol_table_lookup(variable_map, operand_value, operand_length); + if pseudo_symbol^.allocated = false then + pseudo_symbol^.allocated := true; + pseudo_symbol^.counter := temporary_variable_counter; + + temporary_variable_counter := temporary_variable_counter + pseudo_symbol^.rtl_type^.size + end; + return pseudo_symbol +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: ^ElnaRtlInstruction, variable_map: ^ElnaSymbolTable); +var + pseudo_symbol: ^ElnaRtlInfo; + store_instruction: ^ElnaRtlInstruction; +begin + if instruction^.operands[1].kind = ElnaRtlKind.pseudo then + store_instruction := elna_rtl_instruction_create(ElnaRtlOperator.sw); + store_instruction^.next := instruction^.next; + + pseudo_symbol := elna_alloc_variable(instruction^.operands[1].value, instruction^.operands[1].length, + variable_map); + elna_rtl_instruction_set_operand(store_instruction, 1, ElnaRtlKind.register, ElnaRtlRegister.t0, 0); + elna_rtl_instruction_set_operand(store_instruction, 2, ElnaRtlKind.offset, ElnaRtlRegister.sp, pseudo_symbol^.counter); + + instruction^.next := store_instruction; + elna_rtl_instruction_set_operand(instruction, 1, ElnaRtlKind.register, ElnaRtlRegister.t0, 0) + end +end; + +proc elna_alloc_load_address(instruction: ^ElnaRtlInstruction, variable_map: ^ElnaSymbolTable); +var + pseudo_symbol: ^ElnaRtlInfo; +begin + if instruction^.operands[2].kind = ElnaRtlKind.pseudo then + pseudo_symbol := elna_alloc_variable(instruction^.operands[2].value, instruction^.operands[2].length, + variable_map); + instruction^.operator := ElnaRtlOperator.addi; + + elna_rtl_instruction_set_operand(instruction, 2, ElnaRtlKind.register, ElnaRtlRegister.sp, 0); + elna_rtl_instruction_set_operand(instruction, 3, ElnaRtlKind.immediate, pseudo_symbol^.counter, 0) + end; + if instruction^.operands[1].kind = ElnaRtlKind.pseudo then + elna_alloc_operation_target(instruction, variable_map) + end +end; + +proc elna_alloc_store(instruction: ^ElnaRtlInstruction, variable_map: ^ElnaSymbolTable); +var + old_instruction: ^ElnaRtlInstruction; + pseudo_symbol: ^ElnaRtlInfo; +begin + if instruction^.operands[2].kind = ElnaRtlKind.pseudo then + old_instruction := malloc(#size(ElnaRtlInstruction)); + memcpy(old_instruction, instruction, #size(ElnaRtlInstruction)); + + pseudo_symbol := elna_alloc_variable(instruction^.operands[2].value, instruction^.operands[2].length, + variable_map); + instruction^.operator := ElnaRtlOperator.lw; + + elna_rtl_instruction_set_operand(instruction, 1, ElnaRtlKind.register, ElnaRtlRegister.t1, 0); + elna_rtl_instruction_set_operand(instruction, 2, ElnaRtlKind.offset, ElnaRtlRegister.sp, pseudo_symbol^.counter); + + instruction^.next := old_instruction; + elna_rtl_instruction_set_operand(old_instruction, 2, ElnaRtlKind.offset, ElnaRtlRegister.t1, 0) + end +end; + +proc elna_alloc_load(instruction: ^ElnaRtlInstruction, variable_map: ^ElnaSymbolTable); +var + old_instruction: ^ElnaRtlInstruction; + pseudo_symbol: ^ElnaRtlInfo; +begin + if instruction^.operands[1].kind = ElnaRtlKind.pseudo then + old_instruction := malloc(#size(ElnaRtlInstruction)); + memcpy(old_instruction, instruction, #size(ElnaRtlInstruction)); + + pseudo_symbol := elna_alloc_variable(instruction^.operands[1].value, instruction^.operands[1].length, + variable_map); + old_instruction^.operator := ElnaRtlOperator.sw; + + elna_rtl_instruction_set_operand(old_instruction, 1, ElnaRtlKind.register, ElnaRtlRegister.t1, 0); + elna_rtl_instruction_set_operand(old_instruction, 2, ElnaRtlKind.offset, ElnaRtlRegister.sp, pseudo_symbol^.counter); + + instruction^.next := old_instruction; + elna_rtl_instruction_set_operand(instruction, 1, ElnaRtlKind.register, ElnaRtlRegister.t1, 0) + end +end; + +proc elna_alloc_instruction(instruction: ^ElnaRtlInstruction, variable_map: ^ElnaSymbolTable); +var + pseudo_symbol: ^ElnaRtlInfo; + old_instruction: ^ElnaRtlInstruction; +begin + if instruction^.operator = ElnaRtlOperator.move then + if instruction^.operands[1].kind = ElnaRtlKind.pseudo then + pseudo_symbol := elna_alloc_variable(instruction^.operands[1].value, instruction^.operands[1].length, + variable_map); + instruction^.operator = ElnaRtlOperator.sw; + + instruction^.operands[1].kind := instruction^.operands[2].kind; + instruction^.operands[1].value := instruction^.operands[2].value; + instruction^.operands[1].length := instruction^.operands[2].length; + elna_rtl_instruction_set_operand(instruction, 2, ElnaRtlKind.offset, ElnaRtlRegister.sp, pseudo_symbol^.counter); + + goto elna_alloc_instruction_end + end; + if instruction^.operands[2].kind = ElnaRtlKind.pseudo then + pseudo_symbol := elna_alloc_variable(instruction^.operands[2].value, instruction^.operands[2].length, + variable_map); + instruction^.operator = ElnaRtlOperator.lw; + elna_rtl_instruction_set_operand(instruction, 2, ElnaRtlKind.offset, ElnaRtlRegister.sp, pseudo_symbol^.counter); + + goto elna_alloc_instruction_end + end + elsif instruction^.operator = ElnaRtlOperator.la then + elna_alloc_load_address(instruction, variable_map) + elsif instruction^.operator = ElnaRtlOperator.lw then + elna_alloc_load(instruction, variable_map) + elsif instruction^.operator = ElnaRtlOperator.sw then + elna_alloc_store(instruction, variable_map) + elsif instruction^.operator = ElnaRtlOperator._or then + elna_alloc_operation_target(instruction, variable_map) + elsif instruction^.operator = ElnaRtlOperator.and then + elna_alloc_operation_target(instruction, variable_map) + elsif instruction^.operator = ElnaRtlOperator.mul then + elna_alloc_operation_target(instruction, variable_map) + elsif instruction^.operator = ElnaRtlOperator.sub then + elna_alloc_operation_target(instruction, variable_map) + elsif instruction^.operator = ElnaRtlOperator.add then + elna_alloc_operation_target(instruction, variable_map) + elsif instruction^.operator = ElnaRtlOperator._xor then + elna_alloc_operation_target(instruction, variable_map) + elsif instruction^.operator = ElnaRtlOperator.rem then + elna_alloc_operation_target(instruction, variable_map) + elsif instruction^.operator = ElnaRtlOperator.slt then + elna_alloc_operation_target(instruction, variable_map) + elsif instruction^.operator = ElnaRtlOperator.beqz then + if instruction^.operands[1].kind = ElnaRtlKind.pseudo then + old_instruction := malloc(#size(ElnaRtlInstruction)); + memcpy(old_instruction, instruction, #size(ElnaRtlInstruction)); + + pseudo_symbol := elna_alloc_variable(instruction^.operands[1].value, instruction^.operands[1].length, + variable_map); + instruction^.operator := ElnaRtlOperator.lw; + + elna_rtl_instruction_set_operand(instruction, 1, ElnaRtlKind.register, ElnaRtlRegister.t0, 0); + elna_rtl_instruction_set_operand(instruction, 2, ElnaRtlKind.offset, ElnaRtlRegister.sp, pseudo_symbol^.counter); + + instruction^.next := old_instruction; + elna_rtl_instruction_set_operand(old_instruction, 1, ElnaRtlKind.register, ElnaRtlRegister.t0, 0); + + goto elna_alloc_instruction_end + end + elsif instruction^.operator = ElnaRtlOperator.seqz then + elna_alloc_operation_target(instruction, variable_map) + elsif instruction^.operator = ElnaRtlOperator.snez then + elna_alloc_operation_target(instruction, variable_map) + elsif instruction^.operator = ElnaRtlOperator.xori then + elna_alloc_operation_target(instruction, variable_map) + end; + .elna_alloc_instruction_end; +end; + +proc elna_riscv_instruction(instruction: ^ElnaRtlInstruction); +var + argument_count: Word; + current_argument: Word; + operand_value: Word; +begin + argument_count := 0; + + if instruction^.operator = ElnaRtlOperator.label then + _write_label(instruction^.operands[1].value, instruction^.operands[1].length); + _write_c(':') + elsif instruction^.operator = ElnaRtlOperator.allocate_stack then + operand_value := instruction^.operands[1].value; + + (* 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^.operator = ElnaRtlOperator.ret then + operand_value := instruction^.operands[1].value; + + (* 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^.operator) + 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: ^ElnaTacInstruction, variable_map: ^ElnaSymbolTable); +var + last_copy: ^ElnaRtlInstruction; + current_copy: ^ElnaRtlInstruction; + next_copy: ^ElnaRtlInstruction; + first_copy: ^ElnaRtlInstruction; +begin + if instruction <> nil then + first_copy := elna_rtl_instruction(instruction, @current_copy, variable_map); + 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_copy, variable_map); + + instruction := instruction^.next; + current_copy^.next := next_copy; + current_copy := last_copy; + goto elna_rtl_instructions_start + end; + + return first_copy +end; + +proc elna_alloc_instructions(instruction: ^ElnaRtlInstruction, variable_map: ^ElnaSymbolTable); +begin + .elna_alloc_instructions_start; + + if instruction <> nil then + elna_alloc_instruction(instruction, variable_map); + instruction := instruction^.next; + goto elna_alloc_instructions_start + end +end; + +proc elna_riscv_instructions(instruction: ^ElnaRtlInstruction); +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: ^ElnaRtlProcedure); +var + stack_instruction: ^ElnaRtlInstruction; +begin + .elna_alloc_procedure_loop; + temporary_variable_counter := 0; + + elna_alloc_instructions(rtl_declaration^.body, rtl_declaration^.variable_map); + + stack_instruction := elna_rtl_instruction_create(ElnaRtlOperator.allocate_stack); + stack_instruction^.next := rtl_declaration^.body; + elna_rtl_instruction_set_operand(stack_instruction, 1, ElnaRtlKind.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, ElnaRtlKind.immediate, temporary_variable_counter, 0); + + elna_instruction_list_concatenate(rtl_declaration^.body, stack_instruction); + + rtl_declaration := rtl_declaration^.next; + if rtl_declaration <> nil then + goto elna_alloc_procedure_loop + end +end; + +proc elna_riscv_procedure(procedure: ^ElnaRtlProcedure); +begin + .elna_riscv_procedure_loop; + + (* Write .type _procedure_name, @function. *) + printf(".type %.*s, @function\n\0", procedure^.length, procedure^.name); + + (* Write procedure label, _procedure_name: *) + printf("%.*s:\n\0", procedure^.length, procedure^.name); + + 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: ^ElnaRtlStaticVariable); +begin + .elna_riscv_variable_loop; + if variable <> 0 then + printf(".type %.*s, @object\n\0", variable^.length, variable^.name); + + printf("%.*s: .zero %i\n\0", variable^.length, variable^.name, variable^.body); + variable := variable^.next; + + goto elna_riscv_variable_loop + end +end; + +proc elna_rtl_module_declaration(tac_module: ^ElnaInstructionModule); +var + result: ^ElnaInstructionModule; +begin + result := malloc(#size(ElnaInstructionModule)); + result^.data := elna_rtl_globals(tac_module^.data); + result^.code := elna_rtl_procedures(tac_module^.code); + + return result +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_length: Word; + result: ^ElnaTreeIntegerLiteral; + buffer: Word; +begin + result := malloc(#size(ElnaTreeIntegerLiteral)); + integer_length := lexer_state.finish - lexer_state.start; + + buffer := malloc(integer_length + 1); + bzero(buffer, integer_length + 1); + memcpy(buffer, lexer_state.start, integer_length); + _elna_lexer_skip_token(); + + result^.kind := ElnaTreeKind.integer_literal; + result^.value := atoi(buffer); + result^.type_decoration := nil; + + return result +end; + +proc elna_parser_boolean_literal(); +var + result: ^ElnaTreeBooleanLiteral; +begin + result := malloc(#size(ElnaTreeBooleanLiteral)); + + result^.kind := ElnaTreeKind.boolean_literal; + result^.value := string_compare(lexer_state.start, 4, "true", 4); + result^.type_decoration := nil; + + _elna_lexer_skip_token(); + + 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: ^ElnaTacOperand); +begin + operand^.kind := ElnaTacKind.immediate; + operand^.value := integer_literal_node^.value; + operand^.length := 0; + + return nil +end; + +proc elna_tac_boolean_literal(boolean_literal_node: ^ElnaTreeBooleanLiteral, operand: ^ElnaTacOperand); +begin + operand^.kind := ElnaTacKind.immediate; + operand^.value := boolean_literal_node^.value; + operand^.length := 0; + + return nil +end; + +proc elna_tac_nil_literal(nil_node: Word, operand: ^ElnaTacOperand); +begin + operand^.kind := ElnaTacKind.immediate; + operand^.value := 0; + operand^.length := 0; + + return nil +end; + +proc elna_parser_character_literal(); +var + result: ^ElnaTreeCharacterLiteral; +begin + result := malloc(#size(ElnaTreeCharacterLiteral)); + + result^.kind := ElnaTreeKind.character_literal; + result^.value := lexer_state.start; + result^.length := lexer_state.finish - lexer_state.start; + result^.type_decoration := nil; + _elna_lexer_skip_token(); + + return result +end; + +proc elna_tac_character_literal(character_literal_node: ^ElnaTreeCharacterLiteral, operand: ^ElnaTacOperand); +begin + operand^.kind := ElnaTacKind.immediate; + operand^.value := character_literal_node^.value; + operand^.length := character_literal_node^.length; + + return nil +end; + +proc elna_parser_variable_expression(); +var + result: ^ElnaTreeVariableExpression; +begin + result := malloc(#size(ElnaTreeVariableExpression)); + + result^.kind := ElnaTreeKind.variable_expression; + result^.name := lexer_state.start; + result^.length := lexer_state.finish - lexer_state.start; + result^.type_decoration := nil; + + _elna_lexer_skip_token(); + + return result +end; + +proc elna_tac_variable_expression(variable_expression: ^ElnaTreeVariableExpression, + symbol_table: ^ElnaSymbolTable, operand: ^ElnaTacOperand); +var + lookup_result: ^ElnaSymbolTemporaryInfo; +begin + lookup_result := elna_symbol_table_lookup(symbol_table, variable_expression^.name, variable_expression^.length); + + if lookup_result <> nil then + operand^.kind := ElnaTacKind.pseudo; + operand^.value := variable_expression^.name; + operand^.length := variable_expression^.length + else + operand^.kind := ElnaTacKind.symbol; + operand^.value := variable_expression^.name; + operand^.length := variable_expression^.length + end; + return nil +end; + +proc elna_parser_string_literal(); +var + result: ^ElnaTreeStringLiteral; +begin + result := malloc(#size(ElnaTreeStringLiteral)); + + result^.kind := ElnaTreeKind.string_literal; + result^.value := lexer_state.start; + result^.length := lexer_state.finish - lexer_state.start; + result^.type_decoration := nil; + + _elna_lexer_skip_token(); + + return result +end; + +proc elna_tac_string_literal(string_literal_node: ^ElnaTreeStringLiteral, + symbol_table: ^ElnaSymbolTable, operand: ^ElnaTacOperand); +var + offset: Word; + first_instruction: Word; + next_instruction: Word; +begin + offset := _add_string(string_literal_node^.value); + + elna_tac_generate_pseudo(@operand^.kind, @operand^.value, @operand^.length, symbol_table); + + first_instruction := elna_tac_instruction_create(ElnaTacOperator.get_address); + elna_tac_instruction_set_operand(first_instruction, 1, operand^.kind, operand^.value, operand^.length); + elna_tac_instruction_set_operand(first_instruction, 2, ElnaTacKind.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, operand^.kind, operand^.value, operand^.length); + elna_tac_instruction_set_operand(next_instruction, 2, operand^.kind, operand^.value, operand^.length); + elna_tac_instruction_set_operand(next_instruction, 3, ElnaTacKind.immediate, offset, 0); + + 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 := lexer_state.start; + result^.length := lexer_state.finish - lexer_state.start; + + _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_square then + simple_expression := elna_parser_array_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: ^ElnaTacOperand); +var + symbol: ^ElnaSymbolTypeInfo; + info_type: ^ElnaType; + parser_node: ^ElnaTreeNamedTypeExpression; +begin + parser_node := trait_node^.argument; + symbol := elna_symbol_table_lookup(@symbol_table_global, parser_node^.name, parser_node^.length); + info_type := symbol^._type; + + operand^.kind := ElnaTacKind.immediate; + operand^.value := info_type^.size; + operand^.length := 0; + + return nil +end; + +proc elna_tac_simple_expression(parser_node: ^ElnaTreeNode, symbol_table: ^ElnaSymbolTable, operand: ^ElnaTacOperand); +var + instruction: Word; +begin + if parser_node^.kind = ElnaTreeKind.character_literal then + instruction := elna_tac_character_literal(parser_node, operand) + elsif parser_node^.kind = ElnaTreeKind.string_literal then + instruction := elna_tac_string_literal(parser_node, symbol_table, operand) + elsif parser_node^.kind = ElnaTreeKind.integer_literal then + instruction := elna_tac_integer_literal(parser_node, operand) + elsif parser_node^.kind = ElnaTreeKind.boolean_literal then + instruction := elna_tac_boolean_literal(parser_node, operand) + elsif parser_node^.kind = ElnaTreeKind.null then + instruction := elna_tac_nil_literal(parser_node, operand) + elsif parser_node^.kind = ElnaTreeKind.trait_expression then + instruction := elna_tac_trait_expression(parser_node, operand) + else + instruction := elna_tac_variable_expression(parser_node, symbol_table, operand) + 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_copy_address(is_address: Word, from_type: Word, from_value: Word, from_length: Word, to_type: Word, to_value: Word, to_length: Word); +var + instruction: Word; +begin + if is_address then + instruction := elna_tac_instruction_create(ElnaTacOperator.copy) + else + instruction := elna_tac_instruction_create(ElnaTacOperator.get_address) + end; + elna_tac_instruction_set_operand(instruction, 1, to_type, to_value, to_length); + elna_tac_instruction_set_operand(instruction, 2, from_type, from_value, from_length); + + return instruction +end; + +proc elna_tac_unary_expression(parser_node: ^ElnaTreeUnaryExpression, symbol_table: ^ElnaSymbolTable, operand: ^ElnaTacOperand); +var + token_kind: Word; + operator: Word; + unary_operand: ^ElnaTreeExpression; + is_address: Word; + first_instruction: Word; + instruction: Word; + base: ElnaTacOperand; +begin + instruction := nil; + if parser_node^.kind = ElnaTreeKind.unary_expression then + operator := parser_node^.operator; + unary_operand := parser_node^.operand + else + operator := 0; + unary_operand := parser_node + end; + first_instruction := elna_tac_designator(unary_operand, symbol_table, @is_address, @base); + + elna_tac_generate_pseudo(@operand^.kind, @operand^.value, @operand^.length, symbol_table); + + if operator = '@' then + instruction := elna_tac_copy_address(is_address, base.kind, base.value, base.length, + operand^.kind, operand^.value, operand^.length) + elsif operator = '-' then + instruction := elna_tac_instruction_create(ElnaTacOperator.negate); + elna_tac_instruction_set_operand(instruction, 1, operand^.kind, operand^.value, operand^.length); + elna_tac_instruction_set_operand(instruction, 2, base.kind, base.value, base.length) + elsif operator = '~' then + instruction := elna_tac_instruction_create(ElnaTacOperator.complement); + elna_tac_instruction_set_operand(instruction, 1, operand^.kind, operand^.value, operand^.length); + elna_tac_instruction_set_operand(instruction, 2, base.kind, base.value, base.length) + elsif is_address then + instruction := elna_tac_instruction_create(ElnaTacOperator.load); + elna_tac_instruction_set_operand(instruction, 1, base.kind, base.value, base.length); + elna_tac_instruction_set_operand(instruction, 2, operand^.kind, operand^.value, operand^.length) + else + instruction := elna_tac_instruction_create(ElnaTacOperator.copy); + elna_tac_instruction_set_operand(instruction, 1, operand^.kind, operand^.value, operand^.length); + elna_tac_instruction_set_operand(instruction, 2, base.kind, base.value, base.length) + end; + 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: ^ElnaSymbolTable, operand: ^ElnaTacOperand); +var + first_instruction: Word; + instruction: Word; + lhs: ElnaTacOperand; + rhs: ElnaTacOperand; +begin + if parser_node^.kind <> ElnaTreeKind.binary_expression then + first_instruction := elna_tac_unary_expression(parser_node, symbol_table, operand) + else + first_instruction := elna_tac_unary_expression(parser_node^.lhs, symbol_table, @lhs); + instruction := elna_tac_unary_expression(parser_node^.rhs, symbol_table, @rhs); + first_instruction := elna_instruction_list_concatenate(first_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_generate_pseudo(@operand^.kind, @operand^.value, @operand^.length, symbol_table); + + elna_tac_instruction_set_operand(instruction, 1, operand^.kind, operand^.value, operand^.length); + elna_tac_instruction_set_operand(instruction, 2, lhs.kind, lhs.value, lhs.length); + elna_tac_instruction_set_operand(instruction, 3, rhs.kind, rhs.value, rhs.length); + + first_instruction := elna_instruction_list_concatenate(first_instruction, instruction) + end; + return first_instruction +end; + +proc elna_parser_call(callee: Word); +var + result: ^ElnaTreeCall; + argument_number: Word; + token_kind: Word; + argument_entry: ^ElnaTreeExpressionList; +begin + result := malloc(#size(ElnaTreeCall)); + result^.kind := ElnaTreeKind.call; + result^.next := nil; + result^.arguments := nil; + + argument_number := 1; + result^.callee := 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; + if result^.arguments = nil then + result^.arguments := malloc(#size(ElnaTreeExpressionList)); + argument_entry := result^.arguments + else + argument_entry^.next := malloc(#size(ElnaTreeExpressionList)); + argument_entry := argument_entry^.next + end; + argument_entry^.next := nil; + argument_entry^.expression := elna_parser_binary_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; + (* Save the number of arguments. *) + result^.count := argument_number - 1; + + return result +end; + +proc elna_tac_call(parsed_call: ^ElnaTreeCall, symbol_table: ^ElnaSymbolTable, operand: ^ElnaTacOperand); +var + parsed_expression: ^ElnaTreeVariableExpression; + instruction: Word; + first_instruction: Word; + current_instruction: Word; + arguments_operand: ^ElnaTacOperand; + call_instruction: Word; + argument_entry: ^ElnaTreeExpressionList; +begin + parsed_expression := parsed_call^.callee; + first_instruction := nil; + arguments_operand := malloc(parsed_call^.count * #size(ElnaTacOperand)); + + elna_tac_generate_pseudo(@operand^.kind, @operand^.value, @operand^.length, symbol_table); + + call_instruction := elna_tac_instruction_create(ElnaTacOperator.proc_call); + elna_tac_instruction_set_operand(call_instruction, 1, ElnaTacKind.symbol, parsed_expression^.name, parsed_expression^.length); + elna_tac_instruction_set_operand(call_instruction, 2, ElnaTacKind.list, arguments_operand, parsed_call^.count); + elna_tac_instruction_set_operand(call_instruction, 3, operand^.kind, operand^.value, operand^.length); + + argument_entry := parsed_call^.arguments; + .elna_tac_call_loop; + + if argument_entry <> nil then + instruction := elna_tac_binary_expression(argument_entry^.expression, symbol_table, arguments_operand); + if first_instruction = nil then + first_instruction := instruction + else + elna_instruction_list_concatenate(current_instruction, instruction) + end; + if instruction <> nil then + current_instruction := instruction + end; + arguments_operand := arguments_operand + #size(ElnaTacOperand); + + argument_entry := argument_entry^.next; + goto elna_tac_call_loop + end; + 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 := lexer_state.start; + result^.length := lexer_state.finish - lexer_state.start; + + _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, ElnaTacKind.symbol, label_with_dot1, label_length1); + return instruction1 +end; + +proc elna_parser_label_declaration(); +var + token_kind: Word; + result: ^ElnaTreeGotoStatement; +begin + _elna_lexer_skip_token(); + _elna_lexer_read_token(@token_kind); + + result := malloc(#size(ElnaTreeLabelDeclaration)); + + result^.kind := ElnaTreeKind.label_declaration; + result^.next := nil; + result^.label := lexer_state.start; + result^.length := lexer_state.finish - lexer_state.start; + + _elna_lexer_skip_token(); + + 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: ^ElnaTacOperand); +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 := elna_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^.kind := ElnaTacKind.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 := lexer_state.start; + result^.length := lexer_state.finish - lexer_state.start; + + _elna_lexer_skip_token(); + + return result +end; + +proc elna_parser_array_access_expression(array: Word); +var + token_kind: Word; + result: ^ElnaTreeArrayAccessExpression; +begin + _elna_lexer_skip_token(); + + result := malloc(#size(ElnaTreeArrayAccessExpression)); + + result^.kind := ElnaTreeKind.array_access_expression; + result^.type_decoration := nil; + result^.array := array; + result^.index := elna_parser_binary_expression(); + + _elna_lexer_read_token(@token_kind); + _elna_lexer_skip_token(); + + return result +end; + +proc elna_tac_dereference_expression(dereference_expression: ^ElnaTreeDereferenceExpression, + symbol_table: ^ElnaSymbolTable, operand: ^ElnaTacOperand); +var + result_instructions: Word; + load_instruction: Word; + is_address: Word; +begin + result_instructions := elna_tac_designator(dereference_expression^.pointer, symbol_table, @is_address, operand); + + if is_address = true then + load_instruction := elna_tac_instruction_create(ElnaTacOperator.load); + elna_tac_instruction_set_operand(load_instruction, 1, operand^.kind, operand^.value, operand^.length); + elna_tac_instruction_set_operand(load_instruction, 2, operand^.kind, operand^.value, operand^.length); + + result_instructions := elna_instruction_list_concatenate(result_instructions, load_instruction) + end; + return result_instructions +end; + +proc elna_tac_designator(parser_node: ^ElnaTreeExpression, symbol_table: ElnaSymbolTable, is_address: Word, operand: ^ElnaTacOperand); +var + field_access_expression: ^ElnaTreeFieldAccessExpression; + result_instructions: Word; + designator_base: ^ElnaTreeExpression; +begin + if parser_node^.kind = ElnaTreeKind.dereference_expression then + result_instructions := elna_tac_dereference_expression(parser_node, symbol_table, operand); + is_address^ := true + elsif parser_node^.kind = ElnaTreeKind.field_access_expression then + field_access_expression := parser_node; + designator_base := field_access_expression^.aggregate; + + if designator_base^.type_decoration = nil then + result_instructions := elna_tac_enumeration_value(field_access_expression, operand); + is_address^ := false + else + result_instructions := elna_tac_field_access_expression(field_access_expression, symbol_table, operand); + is_address^ := true + end; + elsif parser_node^.kind = ElnaTreeKind.array_access_expression then + result_instructions := elna_tac_array_access_expression(parser_node, symbol_table, operand); + is_address^ := true + elsif parser_node^.kind = ElnaTreeKind.call then + result_instructions := elna_tac_call(parser_node, symbol_table, operand); + is_address^ := false + else + result_instructions := elna_tac_simple_expression(parser_node, symbol_table, operand); + is_address^ := false + end; + return result_instructions +end; + +proc elna_tac_field_access_expression(field_access_expression: ^ElnaTreeFieldAccessExpression, + symbol_table: ^ElnaSymbolTable, operand: ^ElnaTacOperand); +var + field_type: ^ElnaType; + first_instruction: Word; + last_instruction: Word; + designator_base: ^ElnaTreeExpression; + aggregate_type: ^ElnaTypeRecord; + field_count: Word; + current_field: ^ElnaTypeField; + field_offset: Word; + is_address: Word; + base: ElnaTacOperand; +begin + designator_base := field_access_expression^.aggregate; + aggregate_type := designator_base^.type_decoration; + + first_instruction := elna_tac_designator(designator_base, symbol_table, @is_address, @base); + + field_count := aggregate_type^.length; + current_field := aggregate_type^.members; + field_offset := 0; + + .elna_tac_field_access_expression_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_field_access_expression_field + end; + elna_tac_generate_pseudo(@operand^.kind, @operand^.value, @operand^.length, symbol_table); + + last_instruction := elna_tac_copy_address(is_address, base.kind, base.value, base.length, operand^.kind, operand^.value, operand^.length); + first_instruction := elna_instruction_list_concatenate(first_instruction, last_instruction); + + last_instruction := elna_tac_instruction_create(ElnaTacOperator.add); + elna_tac_instruction_set_operand(last_instruction, 1, operand^.kind, operand^.value, operand^.length); + elna_tac_instruction_set_operand(last_instruction, 2, ElnaTacKind.immediate, field_offset, 0); + elna_tac_instruction_set_operand(last_instruction, 3, operand^.kind, operand^.value, operand^.length); + + return elna_instruction_list_concatenate(first_instruction, last_instruction) +end; + +proc elna_tac_array_access_expression(array_access_expression: ^ElnaTreeArrayAccessExpression, + symbol_table: ^ElnaSymbolTable, operand: ^ElnaTacOperand); +var + array_instructions: Word; + index_instructions: Word; + offset_instruction: Word; + add_instruction: Word; + is_address: Word; + inter_operand: ElnaTacOperand; + index_type: Word; + index_value: Word; + index_length: Word; + aggregate_type: ^ElnaTypeArray; + designator_base: ^ElnaTreeExpression; + element_type: ^ElnaType; +begin + designator_base := array_access_expression^.array; + aggregate_type := designator_base^.type_decoration; + element_type := aggregate_type^.base; + + index_instructions := elna_tac_binary_expression(array_access_expression^.index, symbol_table, @inter_operand); + elna_tac_generate_pseudo(@index_type, @index_value, @index_length, symbol_table); + + add_instruction := elna_tac_instruction_create(ElnaTacOperator.subtract); + elna_tac_instruction_set_operand(add_instruction, 1, index_type, index_value, index_length); + elna_tac_instruction_set_operand(add_instruction, 2, inter_operand.kind, inter_operand.value, inter_operand.length); + elna_tac_instruction_set_operand(add_instruction, 3, ElnaTacKind.immediate, 1, 0); + + offset_instruction := elna_tac_instruction_create(ElnaTacOperator.multiply); + elna_tac_instruction_set_operand(offset_instruction, 1, index_type, index_value, index_length); + elna_tac_instruction_set_operand(offset_instruction, 2, index_type, index_value, index_length); + elna_tac_instruction_set_operand(offset_instruction, 3, ElnaTacKind.immediate, element_type^.size, 0); + + elna_instruction_list_concatenate(add_instruction, offset_instruction); + index_instructions := elna_instruction_list_concatenate(index_instructions, add_instruction); + + array_instructions := elna_tac_designator(array_access_expression^.array, symbol_table, @is_address, @inter_operand); + elna_tac_generate_pseudo(@operand^.kind, @operand^.value, @operand^.length, symbol_table); + elna_instruction_list_concatenate(offset_instruction, array_instructions); + + array_instructions := elna_tac_copy_address(is_address, inter_operand.kind, inter_operand.value, inter_operand.length, + operand^.kind, operand^.value, operand^.length); + elna_instruction_list_concatenate(offset_instruction, array_instructions); + + add_instruction := elna_tac_instruction_create(ElnaTacOperator.add); + elna_tac_instruction_set_operand(add_instruction, 1, operand^.kind, operand^.value, operand^.length); + elna_tac_instruction_set_operand(add_instruction, 2, operand^.kind, operand^.value, operand^.length); + elna_tac_instruction_set_operand(add_instruction, 3, index_type, index_value, index_length); + + return elna_instruction_list_concatenate(index_instructions, add_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: ^ElnaSymbolTable); +var + is_address: Word; + first_instruction: Word; + instruction: Word; + current_instruction: Word; + operand_type: Word; + operand_value: Word; + operand_length: Word; + assignment_operand: ElnaTacOperand; + assignee: ElnaTacOperand; +begin + first_instruction := elna_tac_designator(parser_tree^.assignee, symbol_table, @is_address, @assignee); + (* Compile the assignment. *) + instruction := elna_tac_binary_expression(parser_tree^.assignment, symbol_table, @assignment_operand); + + if assignee.kind = ElnaTacKind.pseudo then + current_instruction := elna_tac_instruction_create(ElnaTacOperator.copy); + + if is_address then + elna_tac_generate_pseudo(@operand_type, @operand_value, @operand_length, symbol_table); + + (* Save the assignee address on the stack. *) + elna_tac_instruction_set_operand(current_instruction, 1, operand_type, operand_value, operand_length); + elna_tac_instruction_set_operand(current_instruction, 2, assignee.kind, assignee.value, assignee.length); + first_instruction := elna_instruction_list_concatenate(first_instruction, current_instruction); + + if instruction <> nil 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, assignment_operand.kind, assignment_operand.value, assignment_operand.length); + elna_tac_instruction_set_operand(instruction, 2, operand_type, operand_value, operand_length); + + elna_instruction_list_concatenate(current_instruction, instruction) + else + elna_tac_instruction_set_operand(current_instruction, 1, assignee.kind, assignee.value, assignee.length); + elna_tac_instruction_set_operand(current_instruction, 2, assignment_operand.kind, assignment_operand.value, assignment_operand.length); + + first_instruction := elna_instruction_list_concatenate(instruction, current_instruction) + end + else + elna_tac_generate_pseudo(@operand_type, @operand_value, @operand_length, symbol_table); + + (* Save the assignee address on the stack. *) + current_instruction := elna_tac_instruction_create(ElnaTacOperator.get_address); + elna_tac_instruction_set_operand(current_instruction, 1, operand_type, operand_value, operand_length); + elna_tac_instruction_set_operand(current_instruction, 2, assignee.kind, assignee.value, assignee.length); + first_instruction := elna_instruction_list_concatenate(first_instruction, current_instruction); + + if instruction <> nil 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, assignment_operand.kind, assignment_operand.value, assignment_operand.length); + elna_tac_instruction_set_operand(instruction, 2, operand_type, operand_value, operand_length); + + 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: ^ElnaSymbolTable); +var + first_instruction: Word; + instruction: Word; + operand: ElnaTacOperand; +begin + first_instruction := elna_tac_binary_expression(parser_node^.returned, symbol_table, @operand); + + instruction := elna_tac_instruction_create(ElnaTacOperator._return); + elna_tac_instruction_set_operand(instruction, 1, operand.kind, 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 + printf(".L%i\0", counter) + else + printf(".%.*s\0", length, counter); + end; + fflush(nil) +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: ^ElnaSymbolTable); +var + condition_label: Word; + instruction: Word; + current_instruction: Word; + first_instruction: Word; + operand: ElnaTacOperand; +begin + (* Compile condition. *) + first_instruction := elna_tac_binary_expression(parser_node^.condition, symbol_table, @operand); + + (* 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.kind, operand.value, operand.length); + elna_tac_instruction_set_operand(current_instruction, 2, ElnaTacKind.symbol, condition_label, 0); + + first_instruction := elna_instruction_list_concatenate(first_instruction, current_instruction); + + instruction := elna_tac_statements(parser_node^.statements, symbol_table); + if instruction <> nil 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, ElnaTacKind.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(current_statement: ^ElnaTreeStatement, symbol_table: ^ElnaSymbolTable); +var + instruction: Word; + first_instruction: Word; + current_instruction: Word; +begin + first_instruction := nil; + + .elna_tac_statements_loop; + pseudo_counter := 0; + + 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: ^ElnaSymbolTable); +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: ^ElnaSymbolTable); +var + instruction: Word; + operand: ElnaTacOperand; +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) + 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_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; + + entry^ := lexer_state.start; + entry := entry + 4; + + entry^ := lexer_state.finish - lexer_state.start; + 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; + 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; + + entry^ := lexer_state.start; + entry := entry + 4; + + entry^ := lexer_state.finish - lexer_state.start; + 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 := lexer_state.start; + result^.length := lexer_state.finish - lexer_state.start; + _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 := elna_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: + * attr - Local variable attributes. + * temporary_type - Local variable type. + *) +proc _temporary_info_create(attr: 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^.variable_type := temporary_type; + result^.attr := attr; + + return result +end; + +(** + * Parameters: + * symbol_table - Local symbol table. + *) +proc _procedure_info_create(symbol_table: ^ElnaSymbolTable); +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, symbol_table: ^ElnaSymbolTable); +var + info: Word; + variable_type: Word; +begin + variable_type := elna_name_type_expression(parser_node^._type); + + info := _temporary_info_create(0, variable_type); + elna_symbol_table_enter(symbol_table, parser_node^.name, parser_node^.length, info) +end; + +proc elna_name_procedure_temporaries(parser_node: ^ElnaTreeVariableDeclaration, symbol_table: ^ElnaSymbolTable); +begin + .elna_name_procedure_temporaries_loop; + if parser_node <> nil then + elna_name_procedure_temporary(parser_node, symbol_table); + + 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 := lexer_state.start; + result^.length := lexer_state.finish - lexer_state.start; + (* 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 or arrow. *) + _elna_lexer_read_token(@token_kind); + _elna_lexer_skip_token(); + + if token_kind = ElnaLexerKind.arrow then + result^.return_type := elna_parser_type_expression() + else + result^.return_type := nil + end; + + 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: ^ElnaTacStaticVariable); +var + result: ^ElnaRtlStaticVariable; +begin + result := malloc(#size(ElnaRtlStaticVariable)); + + result^.next := nil; + 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: ^ElnaRtlInstruction; + current_instruction: ^ElnaRtlInstruction; + 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, ElnaRtlKind.pseudo, parameter_name, name_length); + elna_rtl_instruction_set_operand(current_instruction, 2, ElnaRtlKind.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; + +(* Returns whether the provided type is array or record. *) +proc elna_type_is_aggregate(_type: ^ElnaType); +var + lhs: Word; + rhs: Word; +begin + lhs := _type^.kind = ElnaTypeKind._record; + rhs := _type^.kind = ElnaTypeKind.array; + + return lhs or rhs +end; + +proc elna_rtl_symbol_table(symbol_table: ^ElnaSymbolTable); +var + variable_map: ^ElnaSymbolTable; + count: Word; + current_entry: ^ElnaSymbolEntry; + pseudo_symbol: ^ElnaRtlInfo; + variable_info: ^ElnaSymbolTemporaryInfo; + byte_array: ^ElnaRtlTypeByteArray; + long_word: ^ElnaRtlTypeWord; +begin + variable_map := malloc(16384); + variable_map^.count := 0; + + count := symbol_table^.count; + current_entry := symbol_table + 4; + + .elna_rtl_symbol_table_loop; + if count > 0 then + variable_info := current_entry^.symbol_info; + + pseudo_symbol := malloc(#size(ElnaRtlInfo)); + pseudo_symbol^.allocated := false; + + if elna_type_is_aggregate(variable_info^.variable_type) then + byte_array := malloc(#size(ElnaRtlTypeByteArray)); + byte_array^.kind := ElnaRtlTypeKind.byte_array; + byte_array^.size := variable_info^.variable_type^.size; + + pseudo_symbol^.rtl_type := byte_array + else + long_word := malloc(#size(ElnaRtlTypeWord)); + long_word^.kind := ElnaRtlTypeKind.long_word; + long_word^.size := variable_info^.variable_type^.size; + + pseudo_symbol^.rtl_type := long_word + end; + elna_symbol_table_enter(variable_map, current_entry^.name, current_entry^.length, pseudo_symbol); + + count := count - 1; + current_entry := current_entry + #size(ElnaSymbolEntry); + + goto elna_rtl_symbol_table_loop + end; + + return variable_map; +end; + +proc elna_rtl_procedure_declaration(tac_declaration: ^ElnaTacProcedure); +var + result: ^ElnaRtlProcedure; + body: ^ElnaRtlInstruction; + parameters: ^ElnaRtlInstruction; +begin + result := malloc(#size(ElnaRtlProcedure)); + + result^.next := nil; + result^.name := tac_declaration^.name; + result^.length := tac_declaration^.length; + + parameters = elna_rtl_parameters(tac_declaration^.parameters, tac_declaration^.count); + result^.variable_map := elna_rtl_symbol_table(tac_declaration^.symbol_table); + body := elna_rtl_instructions(tac_declaration^.body, result^.variable_map); + result^.body := elna_instruction_list_concatenate(parameters, body); + + return result +end; + +proc elna_tac_procedure_declaration(parser_node: ElnaTreeProcedureDeclaration); +var + symbol_info: ^ElnaSymbolProcedureInfo; + result: ^ElnaTacProcedure; + parameter_count: Word; +begin + result := malloc(#size(ElnaTacProcedure)); + result^.next := nil; + + result^.name := parser_node^.name; + result^.length := parser_node^.length; + + symbol_info := elna_symbol_table_lookup(@symbol_table_global, parser_node^.name, parser_node^.length); + + result^.symbol_table := symbol_info^.symbol_table; + + 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: ^ElnaTacStaticVariable); +var + current_copy: ^ElnaRtlStaticVariable; + next_copy: ^ElnaRtlStaticVariable; + first_copy: ^ElnaRtlStaticVariable; +begin + if tac_procedure <> nil 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 <> nil 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: ^ElnaTacProcedure); +var + current_copy: ^ElnaRtlProcedure; + next_copy: ^ElnaRtlProcedure; + first_copy: ^ElnaRtlProcedure; +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: ^ElnaTacProcedure; + current_procedure: ^ElnaTacProcedure; + first_procedure: ^ElnaTacProcedure; +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 := lexer_state.start; + name_length := lexer_state.finish - lexer_state.start; + + _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); + + elna_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_type: Word; + result: ^ElnaTreeVariableDeclaration; +begin + _elna_lexer_read_token(@token_kind); + + name := lexer_state.start; + name_length := lexer_state.finish - lexer_state.start; + + (* Skip the variable name and colon with the type. *) + _elna_lexer_skip_token(); + _elna_lexer_read_token(@token_kind); + _elna_lexer_skip_token(); + + variable_type := 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_type; + + return result +end; + +proc elna_tac_variable_declaration(parser_tree: ^ElnaTreeVariableDeclaration); +var + result: ^ElnaTacStaticVariable; + variable_info: ^ElnaSymbolTemporaryInfo; +begin + result := malloc(#size(ElnaTacStaticVariable)); + variable_info := elna_symbol_table_lookup(@symbol_table_global, parser_tree^.name, parser_tree^.length); + + result^.next := nil; + result^.name := parser_tree^.name; + result^.length := parser_tree^.length; + result^.body := variable_info^.variable_type^.size; + + 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: ^ElnaTacStaticVariable; + current_variable: ^ElnaTacStaticVariable; + first_variable: ^ElnaTacStaticVariable; +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; + +proc elna_tac_module_declaration(parser_node: ^ElnaTreeModuleDeclaration); +var + result: ^ElnaInstructionModule; +begin + result := malloc(#size(ElnaInstructionModule)); + result^.data := elna_tac_var_part(parser_node^.globals); + result^.code := elna_tac_procedures(parser_node^.procedures); + + return result +end; + +proc elna_name_procedure_declaration(parser_node: ^ElnaTreeProcedureDeclaration); +var + new_symbol_table: ^ElnaSymbolTable; + symbol_info: Word; +begin + new_symbol_table := elna_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); + + elna_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: ^ElnaSymbolTable); +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: ^ElnaSymbolTable); +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: ^ElnaSymbolTable); +begin + elna_type_binary_expression(parser_node^.returned, symbol_table) +end; + +proc elna_type_call(parser_node: ^ElnaTreeCall, symbol_table: ^ElnaSymbolTable); +var + argument_tree: ^ElnaTreeExpressionList; +begin + argument_tree := parser_node^.arguments; + + .elna_type_call_argument; + if argument_tree <> nil then + elna_type_binary_expression(argument_tree^.expression, symbol_table); + argument_tree := argument_tree^.next; + + goto elna_type_call_argument + end +end; + +proc elna_type_assign_statement(parser_node: ^ElnaTreeAssignStatement, symbol_table: ^ElnaSymbolTable); +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: ^ElnaSymbolTable); +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: ^ElnaSymbolTable); +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); +begin + parser_node^.type_decoration := word_type +end; + +proc elna_type_integer_literal(parser_node: ^ElnaTreeIntegerLiteral); +begin + parser_node^.type_decoration := word_type +end; + +proc elna_type_string_literal(parser_node: ^ElnaTreeStringLiteral); +begin + parser_node^.type_decoration := word_type +end; + +proc elna_type_boolean_literal(parser_node: ^ElnaTreeBooleanLiteral); +var + symbol_info: ^ElnaSymbolTypeInfo; +begin + symbol_info := elna_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 := elna_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: ^ElnaSymbolTable); +var + variable_info: ^ElnaSymbolInfo; + temporary_info: ^ElnaSymbolTemporaryInfo; +begin + variable_info := elna_symbol_table_lookup(symbol_table, parser_node^.name, parser_node^.length); + + if variable_info = nil then + variable_info := elna_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: ^ElnaSymbolTable); +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: ^ElnaSymbolTable); +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: ^ElnaSymbolTable); +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 := elna_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_array_access_expression(parser_node: ^ElnaTreeArrayAccessExpression, symbol_table: ^ElnaSymbolTable); +var + aggregate_type: ^ElnaTypeArray; + base_expression: ^ElnaTreeExpression; +begin + base_expression := parser_node^.array; + + elna_type_designator(base_expression, symbol_table); + elna_type_binary_expression(parser_node^.index, symbol_table); + + aggregate_type := base_expression^.type_decoration; + parser_node^.type_decoration := aggregate_type^.base +end; + +proc elna_type_designator(parser_node: ^ElnaTreeNode, symbol_table: ^ElnaSymbolTable); +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.array_access_expression then + elna_type_array_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: ^ElnaSymbolTable); +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: ^ElnaSymbolTable); +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; +begin + procedure_info := elna_symbol_table_lookup(@symbol_table_global, parser_node^.name, parser_node^.length); + + elna_type_statements(parser_node^.body, procedure_info^.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, @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 elna_symbol_table_lookup(symbol_table: ^ElnaSymbolTable, symbol_name: Word, name_length: Word); +var + result: Word; + symbol_table_length: Word; + current_name: Word; + current_length: Word; +begin + result := 0; + symbol_table_length := symbol_table^.count; + + (* 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 elna_symbol_table_create(); +var + new_symbol_table: ^ElnaSymbolTable; +begin + new_symbol_table := malloc(12288); + new_symbol_table^.count := 0; + + 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 elna_symbol_table_enter(symbol_table: ^ElnaSymbolTable, 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 elna_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. *) + word_type := malloc(#size(ElnaType)); + word_type^.kind := ElnaTypeKind.primitive; + word_type^.size := 4; + current_info := _type_info_create(word_type); + elna_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); + elna_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); + elna_symbol_table_enter(@symbol_table_global, "Bool", 4, current_info); +end; + +(** + * Initializes the array with character classes. + *) +proc _elna_lexer_classifications(); +var + code: Word; +begin + classification[1] := ElnaLexerClass.eof; + classification[2] := ElnaLexerClass.invalid; + classification[3] := ElnaLexerClass.invalid; + classification[4] := ElnaLexerClass.invalid; + classification[5] := ElnaLexerClass.invalid; + classification[6] := ElnaLexerClass.invalid; + classification[7] := ElnaLexerClass.invalid; + classification[8] := ElnaLexerClass.invalid; + classification[9] := ElnaLexerClass.invalid; + classification[10] := ElnaLexerClass.space; + classification[11] := ElnaLexerClass.space; + classification[12] := ElnaLexerClass.invalid; + classification[13] := ElnaLexerClass.invalid; + classification[14] := ElnaLexerClass.space; + classification[15] := ElnaLexerClass.invalid; + classification[16] := ElnaLexerClass.invalid; + classification[17] := ElnaLexerClass.invalid; + classification[18] := ElnaLexerClass.invalid; + classification[19] := ElnaLexerClass.invalid; + classification[20] := ElnaLexerClass.invalid; + classification[21] := ElnaLexerClass.invalid; + classification[22] := ElnaLexerClass.invalid; + classification[23] := ElnaLexerClass.invalid; + classification[24] := ElnaLexerClass.invalid; + classification[25] := ElnaLexerClass.invalid; + classification[26] := ElnaLexerClass.invalid; + classification[27] := ElnaLexerClass.invalid; + classification[28] := ElnaLexerClass.invalid; + classification[29] := ElnaLexerClass.invalid; + classification[30] := ElnaLexerClass.invalid; + classification[31] := ElnaLexerClass.invalid; + classification[32] := ElnaLexerClass.invalid; + classification[33] := ElnaLexerClass.space; + classification[34] := ElnaLexerClass.single; + classification[35] := ElnaLexerClass.double_quote; + classification[36] := ElnaLexerClass.number_sign; + classification[37] := ElnaLexerClass.other; + classification[38] := ElnaLexerClass.single; + classification[39] := ElnaLexerClass.single; + classification[40] := ElnaLexerClass.single_quote; + classification[41] := ElnaLexerClass.left_paren; + classification[42] := ElnaLexerClass.right_paren; + classification[43] := ElnaLexerClass.asterisk; + classification[44] := ElnaLexerClass.single; + classification[45] := ElnaLexerClass.single; + classification[46] := ElnaLexerClass.minus; + classification[47] := ElnaLexerClass.dot; + classification[48] := ElnaLexerClass.single; + classification[49] := ElnaLexerClass.zero; + classification[50] := ElnaLexerClass.digit; + classification[51] := ElnaLexerClass.digit; + classification[52] := ElnaLexerClass.digit; + classification[53] := ElnaLexerClass.digit; + classification[54] := ElnaLexerClass.digit; + classification[55] := ElnaLexerClass.digit; + classification[56] := ElnaLexerClass.digit; + classification[57] := ElnaLexerClass.digit; + classification[58] := ElnaLexerClass.digit; + classification[59] := ElnaLexerClass.colon; + classification[60] := ElnaLexerClass.single; + classification[61] := ElnaLexerClass.less; + classification[62] := ElnaLexerClass.equals; + classification[63] := ElnaLexerClass.greater; + classification[64] := ElnaLexerClass.other; + classification[65] := ElnaLexerClass.single; + classification[66] := ElnaLexerClass.alpha; + classification[67] := ElnaLexerClass.alpha; + classification[68] := ElnaLexerClass.alpha; + classification[69] := ElnaLexerClass.alpha; + classification[70] := ElnaLexerClass.alpha; + classification[71] := ElnaLexerClass.alpha; + classification[72] := ElnaLexerClass.alpha; + classification[73] := ElnaLexerClass.alpha; + classification[74] := ElnaLexerClass.alpha; + classification[75] := ElnaLexerClass.alpha; + classification[76] := ElnaLexerClass.alpha; + classification[77] := ElnaLexerClass.alpha; + classification[78] := ElnaLexerClass.alpha; + classification[79] := ElnaLexerClass.alpha; + classification[80] := ElnaLexerClass.alpha; + classification[81] := ElnaLexerClass.alpha; + classification[82] := ElnaLexerClass.alpha; + classification[83] := ElnaLexerClass.alpha; + classification[84] := ElnaLexerClass.alpha; + classification[85] := ElnaLexerClass.alpha; + classification[86] := ElnaLexerClass.alpha; + classification[87] := ElnaLexerClass.alpha; + classification[88] := ElnaLexerClass.alpha; + classification[89] := ElnaLexerClass.alpha; + classification[90] := ElnaLexerClass.alpha; + classification[91] := ElnaLexerClass.alpha; + classification[92] := ElnaLexerClass.single; + classification[93] := ElnaLexerClass.backslash; + classification[94] := ElnaLexerClass.single; + classification[95] := ElnaLexerClass.single; + classification[96] := ElnaLexerClass.alpha; + classification[97] := ElnaLexerClass.other; + classification[98] := ElnaLexerClass.hex; + classification[99] := ElnaLexerClass.hex; + classification[100] := ElnaLexerClass.hex; + classification[101] := ElnaLexerClass.hex; + classification[102] := ElnaLexerClass.hex; + classification[103] := ElnaLexerClass.hex; + classification[104] := ElnaLexerClass.alpha; + classification[105] := ElnaLexerClass.alpha; + classification[106] := ElnaLexerClass.alpha; + classification[107] := ElnaLexerClass.alpha; + classification[108] := ElnaLexerClass.alpha; + classification[109] := ElnaLexerClass.alpha; + classification[110] := ElnaLexerClass.alpha; + classification[111] := ElnaLexerClass.alpha; + classification[112] := ElnaLexerClass.alpha; + classification[113] := ElnaLexerClass.alpha; + classification[114] := ElnaLexerClass.alpha; + classification[115] := ElnaLexerClass.alpha; + classification[116] := ElnaLexerClass.alpha; + classification[117] := ElnaLexerClass.alpha; + classification[118] := ElnaLexerClass.alpha; + classification[119] := ElnaLexerClass.alpha; + classification[120] := ElnaLexerClass.alpha; + classification[121] := ElnaLexerClass.x; + classification[122] := ElnaLexerClass.alpha; + classification[123] := ElnaLexerClass.alpha; + classification[124] := ElnaLexerClass.other; + classification[125] := ElnaLexerClass.single; + classification[126] := ElnaLexerClass.other; + classification[127] := ElnaLexerClass.single; + classification[128] := ElnaLexerClass.invalid; + + code := 129; + + (* Set the remaining 129 - 256 bytes to transitionClassOther. *) + .create_classification_loop; + 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 + 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. *) + column_position := character_class - 1; + column_position := column_position * 8; + + target := @transition_table[current_state]; + + 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: ^ElnaLexerTransition; +begin + transition := _elna_lexer_get_transition(current_state, character_class); + + transition^.action := action; + transition^.next_state := 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; + +(** + * One time lexer initialization. + *) +proc _elna_lexer_initialize(code_pointer: Word); +begin + _elna_lexer_classifications(); + _elna_lexer_transitions(); + + lexer_state.start := code_pointer; + lexer_state.finish := code_pointer +end; + +proc _elna_lexer_next_transition(); +var + current_character: Word; +begin + current_character := _load_byte(lexer_state.finish); + + return _elna_lexer_get_transition(lexer_state.state, classification[current_character + 1]) +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 + elsif first_character = '-' then + result := ElnaLexerKind.arrow + 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 + intermediate: Word; +begin + if action_to_perform = ElnaLexerAction.none then + elsif action_to_perform = ElnaLexerAction.accumulate then + lexer_state.finish := lexer_state.finish + 1 + elsif action_to_perform = ElnaLexerAction.skip then + lexer_state.start := lexer_state.start + 1; + lexer_state.finish := lexer_state.finish + 1 + elsif action_to_perform = ElnaLexerAction.single then + lexer_state.finish := lexer_state.finish + 1; + + intermediate := elna_lexer_classify_single(lexer_state.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(lexer_state.start); + kind^ := intermediate + elsif action_to_perform = ElnaLexerAction.composite then + intermediate := elna_lexer_classify_composite(lexer_state.start, lexer_state.finish); + kind^ := intermediate; + + lexer_state.finish := lexer_state.finish + 1 + elsif action_to_perform = ElnaLexerAction.key_id then + intermediate := elna_lexer_classify_keyword(lexer_state.start, lexer_state.finish); + kind^ := intermediate + elsif action_to_perform = ElnaLexerAction.integer then + intermediate := elna_lexer_classify_integer(lexer_state.start, lexer_state.finish); + kind^ := intermediate + elsif action_to_perform = ElnaLexerAction.delimited then + lexer_state.finish := lexer_state.finish + 1; + + intermediate := elna_lexer_classify_delimited(lexer_state.start, lexer_state.finish); + kind^ := intermediate + end +end; + +proc _elna_lexer_execute_transition(kind: Word); +var + next_transition: ^ElnaLexerTransition; + global_state: Word; +begin + next_transition := _elna_lexer_next_transition(); + global_state := @lexer_state; + + global_state^ := next_transition^.next_state; + _elna_lexer_execute_action(next_transition^.action, kind); + + return next_transition^.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. + * Resets the lexer state for reading the next token. + *) +proc _elna_lexer_read_token(kind: Word); +begin + lexer_state.state := ElnaLexerState.start; + lexer_state.finish := lexer_state.start; + + _elna_lexer_advance_token(kind) +end; + +(** + * Advances the token stream past the last read token. + *) +proc _elna_lexer_skip_token(); +begin + lexer_state.start := lexer_state.finish +end; + +proc _initialize_global_state(); +begin + compiler_strings_position := @compiler_strings; + source_code := malloc(495616); +end; + +(* + * Entry point. + *) +proc main(); +var + last_read: Word; + offset: Word; +begin + _initialize_global_state(); + _elna_lexer_initialize(source_code); + elna_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; diff --git a/boot/stage20/linker.arg b/boot/stage20/linker.arg new file mode 100644 index 0000000..e69de29 --- /dev/null +++ b/boot/stage20/linker.arg |