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------------------------------------------------------------------------------
-- --
-- GNAT COMPILER COMPONENTS --
-- --
-- L I B . X R E F --
-- --
-- S p e c --
-- --
-- $Revision$
-- --
-- Copyright (C) 1998-2001, 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). --
-- --
------------------------------------------------------------------------------
-- This package contains for collecting and outputting cross-reference
-- information.
with Einfo; use Einfo;
with Types; use Types;
package Lib.Xref is
-------------------------------------------------------
-- Format of Cross-Reference Information in ALI File --
-------------------------------------------------------
-- Cross-reference sections follow the dependency section (D lines) in
-- an ALI file, so that they need not be read by gnatbind, gnatmake etc.
--
-- A cross reference section has a header of the form
--
-- X dependency-number filename
--
-- This header precedes xref information (entities/references from
-- the unit, identified by dependency number and file name. The
-- dependency number is the index into the generated D lines and
-- is ones origin (i.e. 2 = reference to second generated D line).
--
-- Note that the filename here will reflect the original name if
-- a Source_Reference pragma was encountered (since all line number
-- references will be with respect to the original file).
--
-- The lines following the header look like
--
-- line type col level entity renameref typeref ref ref ref
--
-- line is the line number of the referenced entity. It starts
-- in column one.
--
-- type is a single letter identifying the type of the entity.
-- See next section (Cross-Reference Entity Identifiers) for a
-- full list of the characters used).
--
-- col is the column number of the referenced entity
--
-- level is a single character that separates the col and
-- entity fields. It is an asterisk for a top level library
-- entity that is publicly visible, and space otherwise.
--
-- entity is the name of the referenced entity, with casing in
-- the canical casing for the source file where it is defined.
-- renameref provides information on renaming. If the entity is
-- a package, object or overloadable entity which is declared by
-- a renaming declaration, and the renaming refers to an entity
-- with a simple identifier or expanded name, then renameref has
-- the form:
--
-- =line:col
--
-- Here line:col give the reference to the identifier that
-- appears in the renaming declaration. Note that we never need
-- a file entry, since this identifier is always in the current
-- file in which the entity is declared. Currently, renameref
-- appears only for the simple renaming case. If the renaming
-- reference is a complex expressions, then renameref is omitted.
--
-- typeref is the reference for a related type. This part is
-- optional. It is present for the following cases:
--
-- derived types (points to the parent type) LR=<>
-- access types (points to designated type) LR=()
-- subtypes (points to ancestor type) LR={}
-- functions (points to result type) LR={}
-- enumeration literals (points to enum type) LR={}
-- objects and components (points to type) LR={}
--
-- In the above list LR shows the brackets used in the output,
-- which has one of the two following forms:
--
-- L file | line type col R user entity
-- L name-in-lower-case R standard entity
--
-- For the form for a user entity, file is the dependency number
-- of the file containing the declaration of the related type.
-- This number and the following vertical bar are omitted if the
-- relevant type is defined in the same file as the current entity.
-- The line, type, col are defined as previously described, and
-- specify the location of the relevant type declaration in the
-- referenced file. For the standard entity form, the name between
-- the brackets is the normal name of the entity in lower case.
--
-- There may be zero or more ref entries on each line
--
-- file | line type col [...]
--
-- file is the dependency number of the file with the reference.
-- It and the following vertical bar are omitted if the file is
-- the same as the previous ref, and the refs for the current
-- file are first (and do not need a bar).
--
-- type is one of
-- r = reference
-- m = modification
-- b = body entity
-- c = completion of private or incomplete type
-- x = type extension
-- i = implicit reference
-- e = end of spec
-- t = end of body
--
-- b is used for spec entities that are repeated in a body,
-- including the unit (subprogram, package, task, protected
-- body, protected entry) name itself, and in the case of a
-- subprogram, the formals. This letter is also used for the
-- occurrence of entry names in accept statements. Such entities
-- are not considered to be definitions for cross-referencing
-- purposes, but rather are considered to be references to the
-- corresponding spec entities, marked with this special type.
--
-- c is similarly used to mark the completion of a private or
-- incomplete type. Again, the completion is not regarded as
-- a separate definition, but rather a reference to the initial
-- declaration, marked with this special type.
--
-- x is used to identify the reference as the entity from which
-- a tagged type is extended. This allows immediate access to
-- the parent of a tagged type.
--
-- i is used to identify a reference to the entity in a generic
-- actual or in a default in a call. The node that denotes the
-- entity does not come from source, but it has the Sloc of the
-- source node that generates the implicit reference, and it is
-- useful to record this one.
--
-- e is used to identify the end of a construct in the following
-- cases:
--
-- Block Statement end [block_IDENTIFIER];
-- Loop Statement end loop [loop_IDENTIFIER];
-- Package Specification end [[PARENT_UNIT_NAME .] IDENTIFIER];
-- Task Definition end [task_IDENTIFIER];
-- Protected Definition end [protected_IDENTIFIER];
-- Record Definition end record;
--
-- Note that 'e' entries are special in that you get they appear
-- even in referencing units (normally xref entries appear only
-- for references in the extended main source unit (see Lib) to
-- which the ali applies. But 'e' entries are really structural
-- and simply indicate where packages end. This information can
-- be used to reconstruct scope information for any entities
-- referenced from within the package.
--
-- t is similarly used to identify the end of a corresponding
-- body (such a reference always links up with a b reference)
--
-- Subprogram Body end [DESIGNATOR];
-- Package Body end [[PARENT_UNIT_NAME .] IDENTIFIER];
-- Task Body end [task_IDENTIFIER];
-- Entry Body end [entry_IDENTIFIER];
-- Protected Body end [protected_IDENTIFIER]
-- Accept Statement end [entry_IDENTIFIER]];
--
-- Note that in the case of accept statements, there can
-- be multiple b and T/t entries for the same entity.
--
-- [..] is used for generic instantiation references. These
-- references are present only if the entity in question is
-- a generic entity, and in that case the [..] contains the
-- reference for the instantiation. In the case of nested
-- instantiations, this can be nested [...[...[...]]] etc.
-- The reference is of the form [file|line] no column is
-- present since it is assumed that only one instantiation
-- appears on a single source line. Note that the appearence
-- of file numbers in such references follows the normal
-- rules (present only if needed, and resets the current
-- file for subsequent references).
--
-- Examples:
--
-- 44B5*Flag_Type{boolean} 5r23 6m45 3|9r35 11r56
--
-- This line gives references for the publicly visible Boolean
-- type Flag_Type declared on line 44, column 5. There are four
-- references
--
-- a reference on line 5, column 23 of the current file
--
-- a modification on line 6, column 45 of the current file
--
-- a reference on line 9, column 35 of unit number 3
--
-- a reference on line 11, column 56 of unit number 3
--
-- 2U13 p3=2:35 5b13 8r4 12r13 12t15
--
-- This line gives references for the non-publicly visible
-- procedure p3 declared on line 2, column 13. This procedure
-- renames the procedure whose identifier reference is at
-- line 2 column 35. There are four references:
--
-- the corresponding body entity at line 5, column 13,
-- of the current file.
--
-- a reference (e.g. a call) at line 8 column 4 of the
-- of the current file.
--
-- the END line of the body has an explict reference to
-- the name of the procedure at line 12, column 13.
--
-- the body ends at line 12, column 15, just past this label.
--
-- 16I9*My_Type<2|4I9> 18r8
--
-- This line gives references for the publicly visible Integer
-- derived type My_Type declared on line 16, column 9. It also
-- gives references to the parent type declared in the unit
-- number 2 on line 4, column 9. There is one reference:
--
-- a reference (e.g. a variable declaration) at line 18 column
-- 4 of the current file.
--
-- 10I3*Genv{integer} 3|4I10[6|12]
--
-- This line gives a reference for the entity Genv in a generic
-- package. The reference in file 3, line 4, col 10, refers to
-- an instance of the generic where the instantiation can be
-- found in file 6 at line 12.
--
-- Continuation lines are used if the reference list gets too long,
-- a continuation line starts with a period, and then has references
-- continuing from the previous line. The references are sorted first
-- by unit, then by position in the source.
-- Note on handling of generic entities. The cross-reference is oriented
-- towards source references, so the entities in a generic instantiation
-- are not considered distinct from the entities in the template. All
-- definitions and references from generic instantiations are suppressed,
-- since they will be generated from the template. Any references to
-- entities in a generic instantiation from outside the instantiation
-- are considered to be references to the original template entity.
----------------------------------------
-- Cross-Reference Entity Identifiers --
----------------------------------------
-- In the cross-reference section of the ali file, entity types are
-- identified by a single letter, indicating the entity type. The
-- following table indicates the letter. A space for an entry is
-- used for entities that do not appear in the cross-reference table.
-- For objects, the character * appears in this table. In the xref
-- listing, this character is replaced by the lower case letter that
-- corresponds to the type of the object. For example, if a variable
-- is of a Float type, then, since the type is represented by an
-- upper case F, the object would be represented by a lower case f.
-- A special exception is the case of booleans, whose entities are
-- normal E_Enumeration_Type or E_Enumeration_Subtype entities, but
-- which appear as B/b in the xref lines, rather than E/e.
-- For private types, the character + appears in the table. In this
-- case the kind of the underlying type is used, if available, to
-- determine the character to use in the xref listing. The listing
-- will still include a '+' for a generic private type, for example.
Xref_Entity_Letters : array (Entity_Kind) of Character := (
E_Void => ' ',
E_Variable => '*',
E_Component => '*',
E_Constant => '*',
E_Discriminant => '*',
E_Loop_Parameter => '*',
E_In_Parameter => '*',
E_Out_Parameter => '*',
E_In_Out_Parameter => '*',
E_Generic_In_Out_Parameter => '*',
E_Generic_In_Parameter => '*',
E_Named_Integer => 'N',
E_Named_Real => 'N',
E_Enumeration_Type => 'E', -- B for boolean
E_Enumeration_Subtype => 'E', -- B for boolean
E_Signed_Integer_Type => 'I',
E_Signed_Integer_Subtype => 'I',
E_Modular_Integer_Type => 'M',
E_Modular_Integer_Subtype => 'M',
E_Ordinary_Fixed_Point_Type => 'O',
E_Ordinary_Fixed_Point_Subtype => 'O',
E_Decimal_Fixed_Point_Type => 'D',
E_Decimal_Fixed_Point_Subtype => 'D',
E_Floating_Point_Type => 'F',
E_Floating_Point_Subtype => 'F',
E_Access_Type => 'P',
E_Access_Subtype => 'P',
E_Access_Attribute_Type => 'P',
E_Allocator_Type => ' ',
E_General_Access_Type => 'P',
E_Access_Subprogram_Type => 'P',
E_Access_Protected_Subprogram_Type => 'P',
E_Anonymous_Access_Type => ' ',
E_Array_Type => 'A',
E_Array_Subtype => 'A',
E_String_Type => 'S',
E_String_Subtype => 'S',
E_String_Literal_Subtype => ' ',
E_Class_Wide_Type => 'C',
E_Class_Wide_Subtype => 'C',
E_Record_Type => 'R',
E_Record_Subtype => 'R',
E_Record_Type_With_Private => 'R',
E_Record_Subtype_With_Private => 'R',
E_Private_Type => '+',
E_Private_Subtype => '+',
E_Limited_Private_Type => '+',
E_Limited_Private_Subtype => '+',
E_Incomplete_Type => '+',
E_Task_Type => 'T',
E_Task_Subtype => 'T',
E_Protected_Type => 'W',
E_Protected_Subtype => 'W',
E_Exception_Type => ' ',
E_Subprogram_Type => ' ',
E_Enumeration_Literal => 'n',
E_Function => 'V',
E_Operator => 'V',
E_Procedure => 'U',
E_Entry => 'Y',
E_Entry_Family => 'Y',
E_Block => 'q',
E_Entry_Index_Parameter => '*',
E_Exception => 'X',
E_Generic_Function => 'v',
E_Generic_Package => 'k',
E_Generic_Procedure => 'u',
E_Label => 'L',
E_Loop => 'l',
E_Package => 'K',
-- The following entities are not ones to which we gather
-- cross-references, since it does not make sense to do so
-- (e.g. references to a package are to the spec, not the body)
-- Indeed the occurrence of the body entity is considered to
-- be a reference to the spec entity.
E_Package_Body => ' ',
E_Protected_Object => ' ',
E_Protected_Body => ' ',
E_Task_Body => ' ',
E_Subprogram_Body => ' ');
-- The following table is for information purposes. It shows the
-- use of each character appearing as an entity type.
-- letter lower case usage UPPER CASE USAGE
-- a array object (except string) array type (except string)
-- b Boolean object Boolean type
-- c class-wide object class-wide type
-- d decimal fixed-point object decimal fixed-point type
-- e non-Boolean enumeration object non_Boolean enumeration type
-- f floating-point object floating-point type
-- g (unused) (unused)
-- h (unused) (unused)
-- i signed integer object signed integer type
-- j (unused) (unused)
-- k generic package package
-- l label on loop label on statement
-- m modular integer object modular integer type
-- n enumeration literal named number
-- o ordinary fixed-point object ordinary fixed-point type
-- p access object access type
-- q label on block (unused)
-- r record object record type
-- s string object string type
-- t task object task type
-- u generic procedure procedure
-- v generic function or operator function or operator
-- w protected object protected type
-- x (unused) exception
-- y (unused) entry or entry family
-- z (unused) (unused)
-----------------
-- Subprograms --
-----------------
procedure Generate_Definition (E : Entity_Id);
-- Records the definition of an entity
procedure Generate_Operator_Reference (N : Node_Id);
-- Node N is an operator node, whose entity has been set. If this entity
-- is a user defined operator (i.e. an operator not defined in package
-- Standard), then a reference to the operator is recorded at node N.
procedure Generate_Reference
(E : Entity_Id;
N : Node_Id;
Typ : Character := 'r';
Set_Ref : Boolean := True;
Force : Boolean := False);
-- This procedure is called to record a reference. N is the location
-- of the reference and E is the referenced entity. Typ is one of:
--
-- 'b' body entity (see below)
-- 'c' completion of incomplete or private type (see below)
-- 'E' end of spec (label present)
-- 'e' end of spec (no label present)
-- 'i' implicit reference
-- 'm' modification
-- 'r' standard reference
-- 'T' end of body (label present)
-- 't' end of body (no label present)
-- 'x' type extension
-- ' ' dummy reference (see below)
--
-- Note: all references to incomplete or private types are to the
-- original (incomplete or private type) declaration. The full
-- declaration is treated as a reference with type 'c'.
--
-- Note: all references to packages or subprograms are to the entity
-- for the spec. The entity in the body is treated as a reference
-- with type 'b'. Similar handling for references to subprogram formals.
--
-- The call has no effect if N is not in the extended main source unit.
-- If N is in the extended main source unit, then the Is_Referenced
-- flag of E is set. In addition, if appropriate, a cross-reference
-- entry is made. The entry is made if:
--
-- cross-reference collection is enabled
-- both entity and reference come from source (or Force is True)
-- the entity is one for which xrefs are appropriate
-- the type letter is non-blank
-- the node N is an identifier, defining identifier, or expanded name
--
-- If all these conditions are met, then a cross-reference entry is
-- made for later output when Output_References is called.
--
-- Note: the dummy entry is for the convenience of some callers, who
-- find it easier to pass a space to suppress the entry than to do a
-- specific test. The call has no effect if the type is a space.
--
-- The parameter Set_Ref is normally True, and indicates that in
-- addition to generating a cross-reference, the Referenced flag
-- of the specified entity should be set. If this parameter is
-- False, then setting of the Referenced flag is inhibited.
--
-- The parameter Force is set to True to force a reference to be
-- generated even if Comes_From_Source is false. This is used for
-- certain implicit references, and also for end label references.
procedure Output_References;
-- Output references to the current ali file
end Lib.Xref;