Subversion Repositories openrisc_2011-10-31

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--                                                                          --

--                         GNAT COMPILER COMPONENTS                         --

--                                                                          --

--                             E X P _ I M G V                              --

--                                                                          --

--                                 S p e c                                  --

--                                                                          --

--          Copyright (C) 2000-2007, 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 3,  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 COPYING3.  If not, go to --

-- http://www.gnu.org/licenses for a complete copy of the license.          --

--                                                                          --

-- GNAT was originally developed  by the GNAT team at  New York University. --

-- Extensive contributions were provided by Ada Core Technologies Inc.      --

--                                                                          --

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--  Expand routines for Image, Value and Width attributes. These are the

--  attributes that make use of enumeration type image tables.

with Types; use Types;

package Exp_Imgv is

   procedure Build_Enumeration_Image_Tables (E : Entity_Id; N : Node_Id);

   --  Build the enumeration image tables for E, which is an enumeration

   --  base type. The node N is the point in the tree where the resulting

   --  declarations are to be inserted.

   --

   --    The form of the tables generated is as follows:

   --

   --      xxxS : string := "chars";

   --      xxxI : array (0 .. N) of Natural_8/16/32 := (1, n, .., n);

   --

   --    Here xxxS is a string obtained by concatenating all the names

   --    of the enumeration literals in sequence, representing any wide

   --    characters according to the current wide character encoding

   --    method, and with all letters forced to upper case.

   --

   --    The array xxxI is an array of ones origin indexes to the start

   --    of each name, with one extra entry at the end, which is the index

   --    to the character just past the end of the last literal, i.e. it is

   --    the length of xxxS + 1. The element type is the shortest of the

   --    possible types that will hold all the values.

   --

   --      For example, for the type

   --

   --         type x is (hello,'!',goodbye);

   --

   --      the generated tables would consist of

   --

   --          xxxS : String := "hello'!'goodbye";

   --          xxxI : array (0 .. 3) of Natural_8 := (1, 6, 9, 16);

   --

   --      Here Natural_8 is used since 16 < 2**(8-1)

   --

   --    If the entity E needs the tables constructing, the necessary

   --    declarations are constructed, and the fields Lit_Strings and

   --    Lit_Indexes of E are set to point to the corresponding entities.

   --    If no tables are needed (E is not a user defined enumeration

   --    root type, or pragma Discard_Names is in effect, then the

   --    declarations are not constructed, and the fields remain Empty.

   procedure Expand_Image_Attribute (N : Node_Id);

   --  This procedure is called from Exp_Attr to expand an occurrence

   --  of the attribute Image.

   procedure Expand_Wide_Image_Attribute (N : Node_Id);

   --  This procedure is called from Exp_Attr to expand an occurrence

   --  of the attribute Wide_Image.

   procedure Expand_Wide_Wide_Image_Attribute (N : Node_Id);

   --  This procedure is called from Exp_Attr to expand an occurrence

   --  of the attribute Wide_Wide_Image.

   procedure Expand_Value_Attribute (N : Node_Id);

   --  This procedure is called from Exp_Attr to expand an occurrence

   --  of the attribute Value.

   type Atype is (Normal, Wide, Wide_Wide);

   --  Type of attribute in call to Expand_Width_Attribute

   procedure Expand_Width_Attribute (N : Node_Id; Attr : Atype := Normal);

   --  This procedure is called from Exp_Attr to expand an occurrence of the

   --  attributes Width (Attr = Normal), or Wide_Width (Attr Wide), or

   --  Wide_Wide_Width (Attr = Wide_Wide).

end Exp_Imgv;