| ------------------------------------------------------------------------------ |
| -- -- |
| -- GNAT COMPILER COMPONENTS -- |
| -- -- |
| -- P A R . C H 1 3 -- |
| -- -- |
| -- B o d y -- |
| -- -- |
| -- Copyright (C) 1992-2003 Free Software Foundation, Inc. -- |
| -- -- |
| -- GNAT is free software; you can redistribute it and/or modify it under -- |
| -- terms of the GNU General Public License as published by the Free Soft- -- |
| -- ware Foundation; either version 2, or (at your option) any later ver- -- |
| -- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- |
| -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- |
| -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License -- |
| -- for more details. You should have received a copy of the GNU General -- |
| -- Public License distributed with GNAT; see file COPYING. If not, write -- |
| -- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, -- |
| -- Boston, MA 02110-1301, USA. -- |
| -- -- |
| -- GNAT was originally developed by the GNAT team at New York University. -- |
| -- Extensive contributions were provided by Ada Core Technologies Inc. -- |
| -- -- |
| ------------------------------------------------------------------------------ |
| |
| pragma Style_Checks (All_Checks); |
| -- Turn off subprogram body ordering check. Subprograms are in order |
| -- by RM section rather than alphabetical |
| |
| separate (Par) |
| package body Ch13 is |
| |
| -- Local functions, used only in this chapter |
| |
| function P_Component_Clause return Node_Id; |
| function P_Mod_Clause return Node_Id; |
| |
| -------------------------------------------- |
| -- 13.1 Representation Clause (also I.7) -- |
| -------------------------------------------- |
| |
| -- REPRESENTATION_CLAUSE ::= |
| -- ATTRIBUTE_DEFINITION_CLAUSE |
| -- | ENUMERATION_REPRESENTATION_CLAUSE |
| -- | RECORD_REPRESENTATION_CLAUSE |
| -- | AT_CLAUSE |
| |
| -- ATTRIBUTE_DEFINITION_CLAUSE ::= |
| -- for LOCAL_NAME'ATTRIBUTE_DESIGNATOR use EXPRESSION; |
| -- | for LOCAL_NAME'ATTRIBUTE_DESIGNATOR use NAME; |
| |
| -- Note: in Ada 83, the expression must be a simple expression |
| |
| -- AT_CLAUSE ::= for DIRECT_NAME use at EXPRESSION; |
| |
| -- Note: in Ada 83, the expression must be a simple expression |
| |
| -- ENUMERATION_REPRESENTATION_CLAUSE ::= |
| -- for first_subtype_LOCAL_NAME use ENUMERATION_AGGREGATE; |
| |
| -- ENUMERATION_AGGREGATE ::= ARRAY_AGGREGATE |
| |
| -- RECORD_REPRESENTATION_CLAUSE ::= |
| -- for first_subtype_LOCAL_NAME use |
| -- record [MOD_CLAUSE] |
| -- {COMPONENT_CLAUSE} |
| -- end record; |
| |
| -- Note: for now we allow only a direct name as the local name in the |
| -- above constructs. This probably needs changing later on ??? |
| |
| -- The caller has checked that the initial token is FOR |
| |
| -- Error recovery: cannot raise Error_Resync, if an error occurs, |
| -- the scan is repositioned past the next semicolon. |
| |
| function P_Representation_Clause return Node_Id is |
| For_Loc : Source_Ptr; |
| Name_Node : Node_Id; |
| Prefix_Node : Node_Id; |
| Attr_Name : Name_Id; |
| Identifier_Node : Node_Id; |
| Rep_Clause_Node : Node_Id; |
| Expr_Node : Node_Id; |
| Record_Items : List_Id; |
| |
| begin |
| For_Loc := Token_Ptr; |
| Scan; -- past FOR |
| |
| -- Note that the name in a representation clause is always a simple |
| -- name, even in the attribute case, see AI-300 which made this so! |
| |
| Identifier_Node := P_Identifier (C_Use); |
| |
| -- Check case of qualified name to give good error message |
| |
| if Token = Tok_Dot then |
| Error_Msg_SC |
| ("representation clause requires simple name!"); |
| |
| loop |
| exit when Token /= Tok_Dot; |
| Scan; -- past dot |
| Discard_Junk_Node (P_Identifier); |
| end loop; |
| end if; |
| |
| -- Attribute Definition Clause |
| |
| if Token = Tok_Apostrophe then |
| |
| -- Allow local names of the form a'b'.... This enables |
| -- us to parse class-wide streams attributes correctly. |
| |
| Name_Node := Identifier_Node; |
| while Token = Tok_Apostrophe loop |
| |
| Scan; -- past apostrophe |
| |
| Identifier_Node := Token_Node; |
| Attr_Name := No_Name; |
| |
| if Token = Tok_Identifier then |
| Attr_Name := Token_Name; |
| |
| if not Is_Attribute_Name (Attr_Name) then |
| Signal_Bad_Attribute; |
| end if; |
| |
| if Style_Check then |
| Style.Check_Attribute_Name (False); |
| end if; |
| |
| -- Here for case of attribute designator is not an identifier |
| |
| else |
| if Token = Tok_Delta then |
| Attr_Name := Name_Delta; |
| |
| elsif Token = Tok_Digits then |
| Attr_Name := Name_Digits; |
| |
| elsif Token = Tok_Access then |
| Attr_Name := Name_Access; |
| |
| else |
| Error_Msg_AP ("attribute designator expected"); |
| raise Error_Resync; |
| end if; |
| |
| if Style_Check then |
| Style.Check_Attribute_Name (True); |
| end if; |
| end if; |
| |
| -- We come here with an OK attribute scanned, and the |
| -- corresponding Attribute identifier node stored in Ident_Node. |
| |
| Prefix_Node := Name_Node; |
| Name_Node := New_Node (N_Attribute_Reference, Prev_Token_Ptr); |
| Set_Prefix (Name_Node, Prefix_Node); |
| Set_Attribute_Name (Name_Node, Attr_Name); |
| Scan; |
| end loop; |
| |
| Rep_Clause_Node := New_Node (N_Attribute_Definition_Clause, For_Loc); |
| Set_Name (Rep_Clause_Node, Prefix_Node); |
| Set_Chars (Rep_Clause_Node, Attr_Name); |
| T_Use; |
| |
| Expr_Node := P_Expression_No_Right_Paren; |
| Check_Simple_Expression_In_Ada_83 (Expr_Node); |
| Set_Expression (Rep_Clause_Node, Expr_Node); |
| |
| else |
| TF_Use; |
| Rep_Clause_Node := Empty; |
| |
| -- AT follows USE (At Clause) |
| |
| if Token = Tok_At then |
| Scan; -- past AT |
| Rep_Clause_Node := New_Node (N_At_Clause, For_Loc); |
| Set_Identifier (Rep_Clause_Node, Identifier_Node); |
| Expr_Node := P_Expression_No_Right_Paren; |
| Check_Simple_Expression_In_Ada_83 (Expr_Node); |
| Set_Expression (Rep_Clause_Node, Expr_Node); |
| |
| -- RECORD follows USE (Record Representation Clause) |
| |
| elsif Token = Tok_Record then |
| Record_Items := P_Pragmas_Opt; |
| Rep_Clause_Node := |
| New_Node (N_Record_Representation_Clause, For_Loc); |
| Set_Identifier (Rep_Clause_Node, Identifier_Node); |
| |
| Push_Scope_Stack; |
| Scope.Table (Scope.Last).Etyp := E_Record; |
| Scope.Table (Scope.Last).Ecol := Start_Column; |
| Scope.Table (Scope.Last).Sloc := Token_Ptr; |
| Scan; -- past RECORD |
| Record_Items := P_Pragmas_Opt; |
| |
| -- Possible Mod Clause |
| |
| if Token = Tok_At then |
| Set_Mod_Clause (Rep_Clause_Node, P_Mod_Clause); |
| Set_Pragmas_Before (Mod_Clause (Rep_Clause_Node), Record_Items); |
| Record_Items := P_Pragmas_Opt; |
| end if; |
| |
| if No (Record_Items) then |
| Record_Items := New_List; |
| end if; |
| |
| Set_Component_Clauses (Rep_Clause_Node, Record_Items); |
| |
| -- Loop through component clauses |
| |
| loop |
| if Token not in Token_Class_Name then |
| exit when Check_End; |
| end if; |
| |
| Append (P_Component_Clause, Record_Items); |
| P_Pragmas_Opt (Record_Items); |
| end loop; |
| |
| -- Left paren follows USE (Enumeration Representation Clause) |
| |
| elsif Token = Tok_Left_Paren then |
| Rep_Clause_Node := |
| New_Node (N_Enumeration_Representation_Clause, For_Loc); |
| Set_Identifier (Rep_Clause_Node, Identifier_Node); |
| Set_Array_Aggregate (Rep_Clause_Node, P_Aggregate); |
| |
| -- Some other token follows FOR (invalid representation clause) |
| |
| else |
| Error_Msg_SC ("invalid representation clause"); |
| raise Error_Resync; |
| end if; |
| end if; |
| |
| TF_Semicolon; |
| return Rep_Clause_Node; |
| |
| exception |
| when Error_Resync => |
| Resync_Past_Semicolon; |
| return Error; |
| |
| end P_Representation_Clause; |
| |
| ---------------------- |
| -- 13.1 Local Name -- |
| ---------------------- |
| |
| -- Local name is always parsed by its parent. In the case of its use in |
| -- pragmas, the check for a local name is handled in Par.Prag and allows |
| -- all the possible forms of local name. For the uses in chapter 13, we |
| -- currently only allow a direct name, but this should probably change??? |
| |
| --------------------------- |
| -- 13.1 At Clause (I.7) -- |
| --------------------------- |
| |
| -- Parsed by P_Representation_Clause (13.1) |
| |
| --------------------------------------- |
| -- 13.3 Attribute Definition Clause -- |
| --------------------------------------- |
| |
| -- Parsed by P_Representation_Clause (13.1) |
| |
| --------------------------------------------- |
| -- 13.4 Enumeration Representation Clause -- |
| --------------------------------------------- |
| |
| -- Parsed by P_Representation_Clause (13.1) |
| |
| --------------------------------- |
| -- 13.4 Enumeration Aggregate -- |
| --------------------------------- |
| |
| -- Parsed by P_Representation_Clause (13.1) |
| |
| ------------------------------------------ |
| -- 13.5.1 Record Representation Clause -- |
| ------------------------------------------ |
| |
| -- Parsed by P_Representation_Clause (13.1) |
| |
| ------------------------------ |
| -- 13.5.1 Mod Clause (I.8) -- |
| ------------------------------ |
| |
| -- MOD_CLAUSE ::= at mod static_EXPRESSION; |
| |
| -- Note: in Ada 83, the expression must be a simple expression |
| |
| -- The caller has checked that the initial Token is AT |
| |
| -- Error recovery: cannot raise Error_Resync |
| |
| -- Note: the caller is responsible for setting the Pragmas_Before field |
| |
| function P_Mod_Clause return Node_Id is |
| Mod_Node : Node_Id; |
| Expr_Node : Node_Id; |
| |
| begin |
| Mod_Node := New_Node (N_Mod_Clause, Token_Ptr); |
| Scan; -- past AT |
| T_Mod; |
| Expr_Node := P_Expression_No_Right_Paren; |
| Check_Simple_Expression_In_Ada_83 (Expr_Node); |
| Set_Expression (Mod_Node, Expr_Node); |
| TF_Semicolon; |
| return Mod_Node; |
| end P_Mod_Clause; |
| |
| ------------------------------ |
| -- 13.5.1 Component Clause -- |
| ------------------------------ |
| |
| -- COMPONENT_CLAUSE ::= |
| -- COMPONENT_CLAUSE_COMPONENT_NAME at POSITION |
| -- range FIRST_BIT .. LAST_BIT; |
| |
| -- COMPONENT_CLAUSE_COMPONENT_NAME ::= |
| -- component_DIRECT_NAME |
| -- | component_DIRECT_NAME'ATTRIBUTE_DESIGNATOR |
| -- | FIRST_SUBTYPE_DIRECT_NAME'ATTRIBUTE_DESIGNATOR |
| |
| -- POSITION ::= static_EXPRESSION |
| |
| -- Note: in Ada 83, the expression must be a simple expression |
| |
| -- FIRST_BIT ::= static_SIMPLE_EXPRESSION |
| -- LAST_BIT ::= static_SIMPLE_EXPRESSION |
| |
| -- Note: the AARM V2.0 grammar has an error at this point, it uses |
| -- EXPRESSION instead of SIMPLE_EXPRESSION for FIRST_BIT and LAST_BIT |
| |
| -- Error recovery: cannot raise Error_Resync |
| |
| function P_Component_Clause return Node_Id is |
| Component_Node : Node_Id; |
| Comp_Name : Node_Id; |
| Expr_Node : Node_Id; |
| |
| begin |
| Component_Node := New_Node (N_Component_Clause, Token_Ptr); |
| Comp_Name := P_Name; |
| |
| if Nkind (Comp_Name) = N_Identifier |
| or else Nkind (Comp_Name) = N_Attribute_Reference |
| then |
| Set_Component_Name (Component_Node, Comp_Name); |
| else |
| Error_Msg_N |
| ("component name must be direct name or attribute", Comp_Name); |
| Set_Component_Name (Component_Node, Error); |
| end if; |
| |
| Set_Sloc (Component_Node, Token_Ptr); |
| T_At; |
| Expr_Node := P_Expression_No_Right_Paren; |
| Check_Simple_Expression_In_Ada_83 (Expr_Node); |
| Set_Position (Component_Node, Expr_Node); |
| T_Range; |
| Expr_Node := P_Expression_No_Right_Paren; |
| Check_Simple_Expression_In_Ada_83 (Expr_Node); |
| Set_First_Bit (Component_Node, Expr_Node); |
| T_Dot_Dot; |
| Expr_Node := P_Expression_No_Right_Paren; |
| Check_Simple_Expression_In_Ada_83 (Expr_Node); |
| Set_Last_Bit (Component_Node, Expr_Node); |
| TF_Semicolon; |
| return Component_Node; |
| end P_Component_Clause; |
| |
| ---------------------- |
| -- 13.5.1 Position -- |
| ---------------------- |
| |
| -- Parsed by P_Component_Clause (13.5.1) |
| |
| ----------------------- |
| -- 13.5.1 First Bit -- |
| ----------------------- |
| |
| -- Parsed by P_Component_Clause (13.5.1) |
| |
| ---------------------- |
| -- 13.5.1 Last Bit -- |
| ---------------------- |
| |
| -- Parsed by P_Component_Clause (13.5.1) |
| |
| -------------------------- |
| -- 13.8 Code Statement -- |
| -------------------------- |
| |
| -- CODE_STATEMENT ::= QUALIFIED_EXPRESSION |
| |
| -- On entry the caller has scanned the SUBTYPE_MARK (passed in as the |
| -- single argument, and the scan points to the apostrophe. |
| |
| -- Error recovery: can raise Error_Resync |
| |
| function P_Code_Statement (Subtype_Mark : Node_Id) return Node_Id is |
| Node1 : Node_Id; |
| |
| begin |
| Scan; -- past apostrophe |
| |
| -- If left paren, then we have a possible code statement |
| |
| if Token = Tok_Left_Paren then |
| Node1 := New_Node (N_Code_Statement, Sloc (Subtype_Mark)); |
| Set_Expression (Node1, P_Qualified_Expression (Subtype_Mark)); |
| TF_Semicolon; |
| return Node1; |
| |
| -- Otherwise we have an illegal range attribute. Note that P_Name |
| -- ensures that Token = Tok_Range is the only possibility left here. |
| |
| else -- Token = Tok_Range |
| Error_Msg_SC ("RANGE attribute illegal here!"); |
| raise Error_Resync; |
| end if; |
| |
| end P_Code_Statement; |
| |
| end Ch13; |
