Parse and transpile unary operations
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parent
9bc6b50b94
commit
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GPG Key ID:
A27FDC1E8EE902C0
@ -18,7 +18,7 @@ VAR
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parsed: BOOLEAN;
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BEGIN
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i := 1;
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ALLOCATE(result, TSIZE(CommandLine));
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NEW(result);
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result^.lex := FALSE;
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result^.parse := FALSE;
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MemZero(ADR(result^.input), 256);
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@ -2,7 +2,7 @@ DEFINITION MODULE Lexer;
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FROM FIO IMPORT File;
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FROM Common IMPORT Identifier;
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FROM Common IMPORT Identifier, ShortString;
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TYPE
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PLexerBuffer = POINTER TO CHAR;
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@ -41,7 +41,7 @@ TYPE
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lexerKindNull,
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lexerKindAnd,
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lexerKindOr,
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lexerKindNot,
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lexerKindTilde,
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lexerKindReturn,
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lexerKindDefinition,
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lexerKindRange,
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@ -84,7 +84,8 @@ TYPE
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CASE kind: LexerKind OF
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lexerKindBoolean: booleanKind: BOOLEAN |
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lexerKindIdentifier: identifierKind: Identifier |
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lexerKindInteger: integerKind: INTEGER
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lexerKindInteger: integerKind: INTEGER |
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lexerKindString: stringKind: ShortString
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END
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END;
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PLexerToken = POINTER TO LexerToken;
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@ -294,6 +294,8 @@ BEGIN
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END transition_action_skip;
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(* Delimited string action. *)
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PROCEDURE transition_action_delimited(lexer: PLexer; token: PLexerToken);
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VAR
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text_length: CARDINAL;
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BEGIN
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IF lexer^.Start^ = '(' THEN
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token^.kind := lexerKindComment
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@ -302,6 +304,10 @@ BEGIN
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token^.kind := lexerKindCharacter
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END;
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IF lexer^.Start^ = "'" THEN
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text_length := lexer^.Current - lexer^.Start;
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MemZero(ADR(token^.stringKind), TSIZE(ShortString));
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MemCopy(lexer^.Start, text_length, ADR(token^.stringKind));
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token^.kind := lexerKindString
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END;
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INC(lexer^.Current)
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@ -423,8 +429,8 @@ BEGIN
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IF lexer^.Current^ = ',' THEN
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token^.kind := lexerKindComma
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END;
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IF lexer^.Current^ = ',' THEN
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token^.kind := lexerKindComma
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IF lexer^.Current^ = '~' THEN
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token^.kind := lexerKindTilde
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END;
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IF lexer^.Current^ = ')' THEN
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token^.kind := lexerKindRightParen
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@ -1,9 +1,55 @@
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DEFINITION MODULE Parser;
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FROM Common IMPORT Identifier, PIdentifier;
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FROM Common IMPORT Identifier, PIdentifier, ShortString;
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FROM Lexer IMPORT PLexer;
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TYPE
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AstLiteralKind = (
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astLiteralKindInteger,
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astLiteralKindString,
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astLiteralKindNull
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);
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AstLiteral = RECORD
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CASE kind: AstLiteralKind OF
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astLiteralKindInteger: integer: INTEGER |
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astLiteralKindString: string: ShortString |
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astLiteralKindNull:
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END
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END;
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PAstLiteral = POINTER TO AstLiteral;
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AstUnaryOperator = (
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astUnaryOperatorNot,
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astUnaryOperatorMinus
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);
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AstExpressionKind = (
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astExpressionKindLiteral,
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astExpressionKindIdentifier,
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astExpressionKindArrayAccess,
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astExpressionKindDereference,
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astExpressionKindFieldAccess,
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astExpressionKindUnary
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);
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AstExpression = RECORD
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CASE kind: AstExpressionKind OF
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astExpressionKindLiteral: literal: PAstLiteral |
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astExpressionKindIdentifier: identifier: Identifier |
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astExpressionKindDereference: reference: PAstExpression |
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astExpressionKindArrayAccess:
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array: PAstExpression;
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index: PAstExpression |
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astExpressionKindFieldAccess:
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aggregate: PAstExpression;
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field: Identifier |
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astExpressionKindUnary:
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unary_operator: AstUnaryOperator;
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unary_operand: PAstExpression
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END
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END;
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PAstExpression = POINTER TO AstExpression;
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PPAstExpression = POINTER TO PAstExpression;
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AstImportStatement = RECORD
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package: Identifier;
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symbols: PIdentifier
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@ -74,5 +120,6 @@ PROCEDURE parse_type_part(lexer: PLexer): PPAstTypeDeclaration;
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PROCEDURE parse_variable_part(lexer: PLexer): PPAstVariableDeclaration;
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PROCEDURE parse_constant_part(lexer: PLexer): PPAstConstantDeclaration;
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PROCEDURE parse_import_part(lexer: PLexer): PPAstImportStatement;
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PROCEDURE parse_designator(lexer: PLexer): PAstExpression;
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END Parser.
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@ -58,7 +58,7 @@ PROCEDURE parse_record_type(lexer: PLexer): PAstTypeExpression;
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VAR
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result: PAstTypeExpression;
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BEGIN
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ALLOCATE(result, TSIZE(AstTypeExpression));
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NEW(result);
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result^.kind := astTypeExpressionKindRecord;
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result^.fields := parse_type_fields(lexer);
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@ -69,7 +69,7 @@ VAR
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token: LexerToken;
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result: PAstTypeExpression;
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BEGIN
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ALLOCATE(result, TSIZE(AstTypeExpression));
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NEW(result);
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result^.kind := astTypeExpressionKindPointer;
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token := lexer_current(lexer);
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@ -88,7 +88,7 @@ VAR
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buffer: ARRAY[1..20] OF CHAR;
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result: PAstTypeExpression;
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BEGIN
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ALLOCATE(result, TSIZE(AstTypeExpression));
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NEW(result);
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result^.kind := astTypeExpressionKindArray;
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result^.length := 0;
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@ -116,7 +116,7 @@ VAR
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current_case: PIdentifier;
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case_count: CARDINAL;
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BEGIN
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ALLOCATE(result, TSIZE(AstTypeExpression));
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NEW(result);
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result^.kind := astTypeExpressionKindEnumeration;
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case_count := 1;
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@ -147,10 +147,9 @@ PROCEDURE parse_named_type(lexer: PLexer): PAstTypeExpression;
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VAR
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token: LexerToken;
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result: PAstTypeExpression;
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written_bytes: CARDINAL;
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BEGIN
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token := lexer_current(lexer);
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ALLOCATE(result, TSIZE(AstTypeExpression));
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NEW(result);
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result^.kind := astTypeExpressionKindNamed;
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result^.name := token.identifierKind;
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@ -165,7 +164,7 @@ VAR
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parameter_count: CARDINAL;
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BEGIN
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parameter_count := 0;
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ALLOCATE(result, TSIZE(AstTypeExpression));
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NEW(result);
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result^.kind := astTypeExpressionKindProcedure;
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ALLOCATE(result^.parameters, 1);
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@ -227,7 +226,7 @@ VAR
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BEGIN
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token := lexer_current(lexer);
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ALLOCATE(result, TSIZE(AstTypeDeclaration));
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NEW(result);
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result^.identifier := token.identifierKind;
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token := transpiler_lex(lexer);
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@ -277,7 +276,7 @@ VAR
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token: LexerToken;
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result: PAstVariableDeclaration;
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BEGIN
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ALLOCATE(result, TSIZE(AstVariableDeclaration));
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NEW(result);
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token := lexer_current(lexer);
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result^.variable_name := token.identifierKind;
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@ -329,7 +328,7 @@ VAR
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token: LexerToken;
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result: PAstConstantDeclaration;
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BEGIN
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ALLOCATE(result, TSIZE(AstConstantDeclaration));
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NEW(result);
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token := lexer_current(lexer);
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result^.constant_name := token.identifierKind;
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@ -384,7 +383,7 @@ VAR
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symbol_count: CARDINAL;
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current_symbol: PIdentifier;
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BEGIN
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ALLOCATE(result, TSIZE(AstImportStatement));
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NEW(result);
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symbol_count := 1;
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token := transpiler_lex(lexer);
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@ -446,4 +445,129 @@ BEGIN
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RETURN result
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END parse_import_part;
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PROCEDURE parse_literal(lexer: PLexer): PAstLiteral;
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VAR
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literal: PAstLiteral;
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token: LexerToken;
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BEGIN
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literal := NIL;
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token := lexer_current(lexer);
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IF token.kind = lexerKindInteger THEN
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NEW(literal);
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literal^.kind := astLiteralKindInteger;
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literal^.integer := token.integerKind;
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END;
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IF token.kind = lexerKindCharacter THEN
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NEW(literal);
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literal^.kind := astLiteralKindString;
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literal^.string := token.stringKind;
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END;
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IF token.kind = lexerKindNull THEN
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NEW(literal);
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literal^.kind := astLiteralKindNull;
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END;
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IF literal <> NIL THEN
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token := transpiler_lex(lexer)
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END;
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RETURN literal
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END parse_literal;
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PROCEDURE parse_factor(lexer: PLexer): PAstExpression;
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VAR
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next_token: LexerToken;
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result: PAstExpression;
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literal: PAstLiteral;
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BEGIN
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result := NIL;
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next_token := lexer_current(lexer);
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literal := parse_literal(lexer);
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IF (result = NIL) AND (literal <> NIL) THEN
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NEW(result);
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result^.kind := astExpressionKindLiteral;
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result^.literal := literal;
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END;
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IF (result = NIL) AND (next_token.kind = lexerKindMinus) THEN
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NEW(result);
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next_token := transpiler_lex(lexer);
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result^.kind := astExpressionKindUnary;
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result^.unary_operator := astUnaryOperatorMinus;
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result^.unary_operand := parse_factor(lexer)
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END;
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IF (result = NIL) AND (next_token.kind = lexerKindTilde) THEN
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NEW(result);
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next_token := transpiler_lex(lexer);
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result^.kind := astExpressionKindUnary;
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result^.unary_operator := astUnaryOperatorNot;
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result^.unary_operand := parse_factor(lexer)
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END;
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IF (result = NIL) AND (next_token.kind = lexerKindIdentifier) THEN
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NEW(result);
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result^.kind := astExpressionKindIdentifier;
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result^.identifier := next_token.identifierKind;
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next_token := transpiler_lex(lexer)
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END;
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RETURN result
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END parse_factor;
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PROCEDURE parse_designator(lexer: PLexer): PAstExpression;
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VAR
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next_token: LexerToken;
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inner_expression: PAstExpression;
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designator: PAstExpression;
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handled: BOOLEAN;
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BEGIN
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designator := parse_factor(lexer);
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handled := designator <> NIL;
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next_token := lexer_current(lexer);
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WHILE handled DO
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inner_expression := designator;
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handled := FALSE;
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IF ~handled AND (next_token.kind = lexerKindHat) THEN
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NEW(designator);
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designator^.kind := astExpressionKindDereference;
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designator^.reference := inner_expression;
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next_token := transpiler_lex(lexer);
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handled := TRUE
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END;
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IF ~handled AND (next_token.kind = lexerKindLeftSquare) THEN
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NEW(designator);
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next_token := transpiler_lex(lexer);
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designator^.kind := astExpressionKindArrayAccess;
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designator^.array := inner_expression;
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designator^.index := parse_designator(lexer);
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next_token := transpiler_lex(lexer);
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handled := TRUE
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END;
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IF ~handled AND (next_token.kind = lexerKindDot) THEN
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NEW(designator);
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next_token := transpiler_lex(lexer);
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designator^.kind := astExpressionKindFieldAccess;
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designator^.aggregate := inner_expression;
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designator^.field := next_token.identifierKind;
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next_token := transpiler_lex(lexer);
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handled := TRUE
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END
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END;
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RETURN designator
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END parse_designator;
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END Parser.
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@ -1,6 +1,6 @@
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IMPLEMENTATION MODULE Transpiler;
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FROM FIO IMPORT WriteNBytes, WriteLine, WriteChar, WriteString;
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FROM FIO IMPORT StdErr, WriteNBytes, WriteLine, WriteChar, WriteString;
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FROM SYSTEM IMPORT ADR, ADDRESS, TSIZE;
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FROM NumberIO IMPORT IntToStr;
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@ -9,12 +9,14 @@ FROM MemUtils IMPORT MemCopy, MemZero;
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FROM Common IMPORT Identifier, PIdentifier, ShortString;
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FROM Lexer IMPORT Lexer, LexerToken, lexer_current, lexer_lex, LexerKind;
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FROM Parser IMPORT AstModule, PAstModule, AstTypeExpressionKind,
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FROM Parser IMPORT AstTypeExpressionKind, AstExpressionKind, AstLiteralKind, AstUnaryOperator,
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AstModule, PAstModule, AstExpression, PAstExpression, PAstLiteral,
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PAstConstantDeclaration, PPAstConstantDeclaration,
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AstTypeDeclaration, PAstTypeDeclaration, PPAstTypeDeclaration,
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PAstVariableDeclaration, PPAstVariableDeclaration, PAstImportStatement, PPAstImportStatement,
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PAstTypeExpression, PPAstTypeExpression, AstFieldDeclaration, PAstFieldDeclaration,
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parse_type_expression, parse_variable_part, parse_type_part, parse_constant_part, parse_import_part;
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parse_type_expression, parse_variable_part, parse_type_part, parse_constant_part, parse_import_part,
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parse_designator;
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(* Calls lexer_lex() but skips the comments. *)
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PROCEDURE transpiler_lex(lexer: PLexer): LexerToken;
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@ -110,7 +112,7 @@ VAR
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token: LexerToken;
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result: PAstModule;
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BEGIN
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ALLOCATE(result, TSIZE(AstModule));
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NEW(result);
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token := transpiler_lex(context^.lexer);
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IF token.kind = lexerKindModule THEN
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@ -383,12 +385,12 @@ BEGIN
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RETURN result
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END transpile_procedure_heading;
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PROCEDURE transpile_expression(context: PTranspilerContext; trailing_token: LexerKind);
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PROCEDURE transpile_unchanged(context: PTranspilerContext; trailing_token: LexerKind);
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VAR
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token: LexerToken;
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written_bytes: CARDINAL;
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BEGIN
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token := transpiler_lex(context^.lexer);
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token := lexer_current(context^.lexer);
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WHILE (token.kind <> trailing_token) AND (token.kind <> lexerKindEnd) DO
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written_bytes := 0;
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@ -412,7 +414,7 @@ BEGIN
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WriteString(context^.output, 'AND ');
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written_bytes := 1
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END;
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IF token.kind = lexerKindNot THEN
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IF token.kind = lexerKindTilde THEN
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WriteString(context^.output, 'NOT ');
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written_bytes := 1
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END;
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@ -422,13 +424,90 @@ BEGIN
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END;
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token := transpiler_lex(context^.lexer)
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END
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END transpile_unchanged;
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PROCEDURE parse_expression(lexer: PLexer): PAstExpression;
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VAR
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next_token: LexerToken;
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result: PAstExpression;
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written_bytes: CARDINAL;
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BEGIN
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result := parse_designator(lexer);
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written_bytes := WriteNBytes(StdErr, ADDRESS(lexer^.Current - lexer^.Start), lexer^.Start);
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WriteLine(StdErr);
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RETURN result
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END parse_expression;
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PROCEDURE transpile_unary_operator(context: PTranspilerContext; operator: AstUnaryOperator);
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BEGIN
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IF operator = astUnaryOperatorMinus THEN
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WriteChar(context^.output, '-')
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END;
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IF operator = astUnaryOperatorNot THEN
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WriteChar(context^.output, '~')
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END
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END transpile_unary_operator;
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PROCEDURE transpile_expression(context: PTranspilerContext; expression: PAstExpression);
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VAR
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literal: PAstLiteral;
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buffer: ARRAY[1..20] OF CHAR;
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written_bytes: CARDINAL;
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BEGIN
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IF expression^.kind = astExpressionKindLiteral THEN
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literal := expression^.literal;
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IF literal^.kind = astLiteralKindInteger THEN
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IntToStr(literal^.integer, 0, buffer);
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WriteString(context^.output, buffer);
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END;
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IF literal^.kind = astLiteralKindString THEN
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WriteString(context^.output, literal^.string)
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END
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END;
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IF expression^.kind = astExpressionKindIdentifier THEN
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written_bytes := WriteNBytes(context^.output, ORD(expression^.identifier[1]), ADR(expression^.identifier[2]))
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END;
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IF expression^.kind = astExpressionKindDereference THEN
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transpile_expression(context, expression^.reference);
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WriteChar(context^.output, '^')
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END;
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IF expression^.kind = astExpressionKindArrayAccess THEN
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transpile_expression(context, expression^.array);
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WriteChar(context^.output, '[');
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transpile_expression(context, expression^.index);
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WriteChar(context^.output, ']')
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END;
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IF expression^.kind = astExpressionKindFieldAccess THEN
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transpile_expression(context, expression^.aggregate);
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WriteChar(context^.output, '.');
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written_bytes := WriteNBytes(context^.output, ORD(expression^.field[1]), ADR(expression^.field[2]));
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END;
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IF expression^.kind = astExpressionKindUnary THEN
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transpile_unary_operator(context, expression^.unary_operator);
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transpile_expression(context, expression^.unary_operand)
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END
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END transpile_expression;
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PROCEDURE transpile_if_statement(context: PTranspilerContext);
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VAR
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token: LexerToken;
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expression: PAstExpression;
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lexer: Lexer;
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BEGIN
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WriteString(context^.output, ' IF ');
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transpile_expression(context, lexerKindThen);
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||||
lexer := context^.lexer^;
|
||||
token := transpiler_lex(ADR(lexer));
|
||||
expression := parse_expression(ADR(lexer));
|
||||
|
||||
IF expression <> NIL THEN
|
||||
context^.lexer^ := lexer;
|
||||
transpile_expression(context, expression);
|
||||
WriteChar(context^.output, ' ')
|
||||
END;
|
||||
IF expression = NIL THEN
|
||||
token := transpiler_lex(context^.lexer)
|
||||
END;
|
||||
transpile_unchanged(context, lexerKindThen);
|
||||
|
||||
WriteString(context^.output, 'THEN');
|
||||
WriteLine(context^.output);
|
||||
@ -441,7 +520,8 @@ VAR
|
||||
token: LexerToken;
|
||||
BEGIN
|
||||
WriteString(context^.output, ' WHILE ');
|
||||
transpile_expression(context, lexerKindDo);
|
||||
token := transpiler_lex(context^.lexer);
|
||||
transpile_unchanged(context, lexerKindDo);
|
||||
|
||||
WriteString(context^.output, 'DO');
|
||||
WriteLine(context^.output);
|
||||
@ -450,9 +530,12 @@ BEGIN
|
||||
token := transpiler_lex(context^.lexer)
|
||||
END transpile_while_statement;
|
||||
PROCEDURE transpile_assignment_statement(context: PTranspilerContext);
|
||||
VAR
|
||||
token: LexerToken;
|
||||
BEGIN
|
||||
WriteString(context^.output, ' := ');
|
||||
transpile_expression(context, lexerKindSemicolon);
|
||||
token := transpiler_lex(context^.lexer);
|
||||
transpile_unchanged(context, lexerKindSemicolon);
|
||||
END transpile_assignment_statement;
|
||||
PROCEDURE transpile_call_statement(context: PTranspilerContext);
|
||||
VAR
|
||||
@ -514,7 +597,8 @@ VAR
|
||||
token: LexerToken;
|
||||
BEGIN
|
||||
WriteString(context^.output, ' RETURN ');
|
||||
transpile_expression(context, lexerKindSemicolon)
|
||||
token := transpiler_lex(context^.lexer);
|
||||
transpile_unchanged(context, lexerKindSemicolon)
|
||||
END transpile_return_statement;
|
||||
PROCEDURE transpile_statement(context: PTranspilerContext);
|
||||
VAR
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user