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Diffstat (limited to 'gcc/ada/par-ch13.adb')
| -rw-r--r-- | gcc/ada/par-ch13.adb | 441 |
1 files changed, 441 insertions, 0 deletions
diff --git a/gcc/ada/par-ch13.adb b/gcc/ada/par-ch13.adb new file mode 100644 index 00000000000..03bd7bf1275 --- /dev/null +++ b/gcc/ada/par-ch13.adb @@ -0,0 +1,441 @@ +------------------------------------------------------------------------------ +-- -- +-- GNAT COMPILER COMPONENTS -- +-- -- +-- P A R . C H 1 3 -- +-- -- +-- B o d y -- +-- -- +-- $Revision: 1.34 $ +-- -- +-- Copyright (C) 1992-2001 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, 59 Temple Place - Suite 330, Boston, -- +-- MA 02111-1307, USA. -- +-- -- +-- GNAT was originally developed by the GNAT team at New York University. -- +-- It is now maintained by Ada Core Technologies Inc (http://www.gnat.com). -- +-- -- +------------------------------------------------------------------------------ + +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; + + -- 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; |