diff options
Diffstat (limited to 'lib/Parser/Parser.cc')
| -rw-r--r-- | lib/Parser/Parser.cc | 146 |
1 files changed, 112 insertions, 34 deletions
diff --git a/lib/Parser/Parser.cc b/lib/Parser/Parser.cc index e67dda7..9563650 100644 --- a/lib/Parser/Parser.cc +++ b/lib/Parser/Parser.cc @@ -59,17 +59,56 @@ std::unique_ptr<ExprAST> Parser::ParseIdentifierExpr() { getNextToken(); auto Args = ParseExprList(')', true); if (!Args) return nullptr; + if (CurTok == '[' || CurTok == '.' || CurTok == '^') { + fprintf(stderr, "Error: record/array/pointer access on a function result is not supported at line %d\n", + Lex.getLine()); + return nullptr; + } return std::make_unique<CallExprAST>(IdName, std::move(*Args), Line); } - if (CurTok == '[') { - getNextToken(); - auto Indices = ParseExprList(']', false); - if (!Indices) return nullptr; - return std::make_unique<ArrayAccessExprAST>(IdName, std::move(*Indices), Line); - } + std::vector<DesignatorAccess> Accesses; + if (!ParseDesignatorSuffix(Accesses)) return nullptr; - return std::make_unique<VariableExprAST>(IdName); + // Degrade rule: shapes that existed before designators keep their nodes. + if (Accesses.empty()) + return std::make_unique<VariableExprAST>(IdName); + if (Accesses.size() == 1 && Accesses[0].Kind == AccessKind::Index) + return std::make_unique<ArrayAccessExprAST>(IdName, std::move(Accesses[0].Indices), Line); + return std::make_unique<DesignatorExprAST>(IdName, std::move(Accesses), Line); +} + +// Postfix accessor chain after an identifier: '[' exprs ']' | '.' IDENT | '^' +bool Parser::ParseDesignatorSuffix(std::vector<DesignatorAccess> &Out) { + while (true) { + if (CurTok == '[') { + getNextToken(); + auto Indices = ParseExprList(']', false); + if (!Indices) return false; + DesignatorAccess A; + A.Kind = AccessKind::Index; + A.Indices = std::move(*Indices); + Out.push_back(std::move(A)); + } else if (CurTok == '.') { + getNextToken(); + if (CurTok != tok_identifier) { + fprintf(stderr, "Error: Expected field name after '.' at line %d\n", Lex.getLine()); + return false; + } + DesignatorAccess A; + A.Kind = AccessKind::Field; + A.FieldName = Lex.IdentifierStr; + Out.push_back(std::move(A)); + getNextToken(); + } else if (CurTok == '^') { + getNextToken(); + DesignatorAccess A; + A.Kind = AccessKind::Deref; + Out.push_back(std::move(A)); + } else { + return true; + } + } } std::string Parser::ParseTypeName(bool AllowVoid) { @@ -158,6 +197,27 @@ std::unique_ptr<ExprAST> Parser::ParseUnary() { return std::make_unique<UnaryExprAST>(tok_not, std::move(Operand)); } + // ^<designator> — address-of; the operand must be an lvalue shape. + if (CurTok == '^') { + int Line = Lex.getLine(); + getNextToken(); + if (CurTok != tok_identifier) { + fprintf(stderr, "Error: '^' (address-of) requires a variable, array element or record field at line %d\n", + Line); + return nullptr; + } + std::string BaseName = Lex.IdentifierStr; + getNextToken(); + if (CurTok == '(') { + fprintf(stderr, "Error: cannot take the address of a function result at line %d\n", Line); + return nullptr; + } + std::vector<DesignatorAccess> Accesses; + if (!ParseDesignatorSuffix(Accesses)) return nullptr; + auto Target = std::make_unique<DesignatorExprAST>(BaseName, std::move(Accesses), Line); + return std::make_unique<AddrOfExprAST>(std::move(Target)); + } + if (CurTok == '-') { int Line = Lex.getLine(); getNextToken(); @@ -214,6 +274,7 @@ void Parser::syncToStatementStart() { case tok_else: case tok_endif: case tok_endwhile: case tok_until: case tok_next: case tok_endfunction: case tok_endprocedure: case tok_openfile: case tok_readfile: case tok_writefile: case tok_closefile: + case tok_type: case tok_define: case tok_endtype: return; default: getNextToken(); @@ -229,6 +290,7 @@ std::vector<std::unique_ptr<StmtAST>> Parser::ParseBlock(std::initializer_list<i return false; }; + ++BlockDepth; // 1 = top level (Parse() calls ParseBlock({})) std::vector<std::unique_ptr<StmtAST>> Body; while (!AtTerminator() && CurTok != tok_eof) { if (auto Stmt = ParseStatement()) { @@ -237,6 +299,7 @@ std::vector<std::unique_ptr<StmtAST>> Parser::ParseBlock(std::initializer_list<i syncToStatementStart(); } } + --BlockDepth; return Body; } @@ -470,33 +533,7 @@ std::unique_ptr<StmtAST> Parser::ParseStatementImpl() { return ParseDeclare(); } else if (CurTok == tok_identifier) { - std::string Name = Lex.IdentifierStr; - int Line = Lex.getLine(); - getNextToken(); - - if (CurTok == '[') { - getNextToken(); - auto Indices = ParseExprList(']', false); - if (!Indices) return nullptr; - - if (CurTok != tok_assign) { - fprintf(stderr, "Error: Expected '<-' after array access in assignment\n"); - return nullptr; - } - getNextToken(); - auto Expr = ParseExpression(); - if (!Expr) return nullptr; - return std::make_unique<ArrayAssignStmtAST>(Name, std::move(*Indices), std::move(Expr), Line); - } - - if (CurTok != tok_assign) { - fprintf(stderr, "Error: Expected '<-' after identifier '%s' at line %d\n", Name.c_str(), Line); - return nullptr; - } - getNextToken(); - auto Expr = ParseExpression(); - if (!Expr) return nullptr; - return std::make_unique<AssignStmtAST>(Name, std::move(Expr)); + return ParseAssignStmt(); } else if (CurTok == tok_input) { getNextToken(); @@ -550,8 +587,49 @@ std::unique_ptr<StmtAST> Parser::ParseStatementImpl() { else if (CurTok == tok_closefile) { return ParseCloseFile(); } + else if (CurTok == tok_type) { + return ParseTypeDecl(); + } + else if (CurTok == tok_define) { + fprintf(stderr, "Error: DEFINE (SET literals) is not implemented at line %d\n", Lex.getLine()); + getNextToken(); + return nullptr; + } + else if (CurTok == tok_endtype) { + fprintf(stderr, "Error: ENDTYPE without matching TYPE at line %d\n", Lex.getLine()); + getNextToken(); + return nullptr; + } fprintf(stderr, "Error: Unexpected token at line %d when expecting a statement\n", Lex.getLine()); getNextToken(); // guarantee progress so error recovery cannot loop forever return nullptr; } + +// <designator> <- <expr> +// Bare-name and single-index targets degrade to their legacy nodes so the +// existing assignment code paths stay untouched. +std::unique_ptr<StmtAST> Parser::ParseAssignStmt() { + std::string Name = Lex.IdentifierStr; + int Line = Lex.getLine(); + getNextToken(); + + std::vector<DesignatorAccess> Accesses; + if (!ParseDesignatorSuffix(Accesses)) return nullptr; + + if (CurTok != tok_assign) { + fprintf(stderr, "Error: Expected '<-' after identifier '%s' at line %d\n", Name.c_str(), Line); + return nullptr; + } + getNextToken(); + auto Expr = ParseExpression(); + if (!Expr) return nullptr; + + if (Accesses.empty()) + return std::make_unique<AssignStmtAST>(Name, std::move(Expr)); + if (Accesses.size() == 1 && Accesses[0].Kind == AccessKind::Index) + return std::make_unique<ArrayAssignStmtAST>(Name, std::move(Accesses[0].Indices), std::move(Expr), Line); + + auto Target = std::make_unique<DesignatorExprAST>(Name, std::move(Accesses), Line); + return std::make_unique<DesignatorAssignStmtAST>(std::move(Target), std::move(Expr)); +} |