| ------------------------------------------------------------------------------ |
| -- -- |
| -- GNAT COMPILER COMPONENTS -- |
| -- -- |
| -- E X P _ I M G V -- |
| -- -- |
| -- S p e c -- |
| -- -- |
| -- Copyright (C) 2000-2022, 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. -- |
| -- -- |
| ------------------------------------------------------------------------------ |
| |
| -- 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 : constant string (1 .. M) := "chars"; |
| -- xxxN : constant array (0 .. N) of Index_Type := (i1, i2, .., iN, j); |
| -- |
| -- 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 xxxN is an array of indexes into xxxS pointing 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 : constant string (1 .. 15) := "hello'!'goodbye"; |
| -- xxxN : constant array (0 .. 3) of Integer_8 := (1, 6, 9, 16); |
| -- |
| -- Here Integer_8 is used since 16 < 2**(8-1). |
| -- |
| -- If the entity E needs the tables, the necessary declarations are built |
| -- 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. |
| -- |
| -- If the number of enumeration literals is large enough, a (perfect) hash |
| -- function mapping the literals to their position number is also built and |
| -- requires additional tables. See the System.Perfect_Hash_Generators unit |
| -- for a complete description of this processing. |
| |
| 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_Valid_Value_Attribute (N : Node_Id); |
| -- This procedure is called from Exp_Attr to expand an occurrence of the |
| -- attribute Valid_Value. |
| |
| 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; |
