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------------------------------------------------------------------------------
-- --
-- GNAT COMPILER COMPONENTS --
-- --
-- L I B . X R E F --
-- --
-- B o d y --
-- --
-- Copyright (C) 1998-2019, 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. --
-- --
------------------------------------------------------------------------------
with Atree; use Atree;
with Csets; use Csets;
with Elists; use Elists;
with Errout; use Errout;
with Lib.Util; use Lib.Util;
with Nlists; use Nlists;
with Opt; use Opt;
with Restrict; use Restrict;
with Rident; use Rident;
with Sem; use Sem;
with Sem_Aux; use Sem_Aux;
with Sem_Prag; use Sem_Prag;
with Sem_Util; use Sem_Util;
with Sem_Warn; use Sem_Warn;
with Sinfo; use Sinfo;
with Sinput; use Sinput;
with Snames; use Snames;
with Stringt; use Stringt;
with Stand; use Stand;
with Table; use Table;
with GNAT.Heap_Sort_G;
with GNAT.HTable;
package body Lib.Xref is
------------------
-- Declarations --
------------------
-- The Xref table is used to record references. The Loc field is set
-- to No_Location for a definition entry.
subtype Xref_Entry_Number is Int;
type Xref_Key is record
-- These are the components of Xref_Entry that participate in hash
-- lookups.
Ent : Entity_Id;
-- Entity referenced (E parameter to Generate_Reference)
Loc : Source_Ptr;
-- Location of reference (Original_Location (Sloc field of N parameter
-- to Generate_Reference)). Set to No_Location for the case of a
-- defining occurrence.
Typ : Character;
-- Reference type (Typ param to Generate_Reference)
Eun : Unit_Number_Type;
-- Unit number corresponding to Ent
Lun : Unit_Number_Type;
-- Unit number corresponding to Loc. Value is undefined and not
-- referenced if Loc is set to No_Location.
-- The following components are only used for SPARK cross-references
Ref_Scope : Entity_Id;
-- Entity of the closest subprogram or package enclosing the reference
Ent_Scope : Entity_Id;
-- Entity of the closest subprogram or package enclosing the definition,
-- which should be located in the same file as the definition itself.
end record;
type Xref_Entry is record
Key : Xref_Key;
Ent_Scope_File : Unit_Number_Type;
-- File for entity Ent_Scope
Def : Source_Ptr;
-- Original source location for entity being referenced. Note that these
-- values are used only during the output process, they are not set when
-- the entries are originally built. This is because private entities
-- can be swapped when the initial call is made.
HTable_Next : Xref_Entry_Number;
-- For use only by Static_HTable
end record;
package Xrefs is new Table.Table (
Table_Component_Type => Xref_Entry,
Table_Index_Type => Xref_Entry_Number,
Table_Low_Bound => 1,
Table_Initial => Alloc.Xrefs_Initial,
Table_Increment => Alloc.Xrefs_Increment,
Table_Name => "Xrefs");
--------------
-- Xref_Set --
--------------
-- We keep a set of xref entries, in order to avoid inserting duplicate
-- entries into the above Xrefs table. An entry is in Xref_Set if and only
-- if it is in Xrefs.
Num_Buckets : constant := 2**16;
subtype Header_Num is Integer range 0 .. Num_Buckets - 1;
type Null_Type is null record;
pragma Unreferenced (Null_Type);
function Hash (F : Xref_Entry_Number) return Header_Num;
function Equal (F1, F2 : Xref_Entry_Number) return Boolean;
procedure HT_Set_Next (E : Xref_Entry_Number; Next : Xref_Entry_Number);
function HT_Next (E : Xref_Entry_Number) return Xref_Entry_Number;
function Get_Key (E : Xref_Entry_Number) return Xref_Entry_Number;
pragma Inline (Hash, Equal, HT_Set_Next, HT_Next, Get_Key);
package Xref_Set is new GNAT.HTable.Static_HTable (
Header_Num,
Element => Xref_Entry,
Elmt_Ptr => Xref_Entry_Number,
Null_Ptr => 0,
Set_Next => HT_Set_Next,
Next => HT_Next,
Key => Xref_Entry_Number,
Get_Key => Get_Key,
Hash => Hash,
Equal => Equal);
-----------------------------
-- SPARK Xrefs Information --
-----------------------------
package body SPARK_Specific is separate;
------------------------
-- Local Subprograms --
------------------------
procedure Add_Entry (Key : Xref_Key; Ent_Scope_File : Unit_Number_Type);
-- Add an entry to the tables of Xref_Entries, avoiding duplicates
procedure Generate_Prim_Op_References (Typ : Entity_Id);
-- For a tagged type, generate implicit references to its primitive
-- operations, for source navigation. This is done right before emitting
-- cross-reference information rather than at the freeze point of the type
-- in order to handle late bodies that are primitive operations.
function Lt (T1, T2 : Xref_Entry) return Boolean;
-- Order cross-references
---------------
-- Add_Entry --
---------------
procedure Add_Entry (Key : Xref_Key; Ent_Scope_File : Unit_Number_Type) is
begin
Xrefs.Increment_Last; -- tentative
Xrefs.Table (Xrefs.Last).Key := Key;
-- Set the entry in Xref_Set, and if newly set, keep the above
-- tentative increment.
if Xref_Set.Set_If_Not_Present (Xrefs.Last) then
Xrefs.Table (Xrefs.Last).Ent_Scope_File := Ent_Scope_File;
-- Leave Def and HTable_Next uninitialized
Set_Has_Xref_Entry (Key.Ent);
-- It was already in Xref_Set, so throw away the tentatively-added entry
else
Xrefs.Decrement_Last;
end if;
end Add_Entry;
-----------
-- Equal --
-----------
function Equal (F1, F2 : Xref_Entry_Number) return Boolean is
Result : constant Boolean :=
Xrefs.Table (F1).Key = Xrefs.Table (F2).Key;
begin
return Result;
end Equal;
-------------------------
-- Generate_Definition --
-------------------------
procedure Generate_Definition (E : Entity_Id) is
begin
pragma Assert (Nkind (E) in N_Entity);
-- Note that we do not test Xref_Entity_Letters here. It is too early
-- to do so, since we are often called before the entity is fully
-- constructed, so that the Ekind is still E_Void.
if Opt.Xref_Active
-- Definition must come from source
-- We make an exception for subprogram child units that have no spec.
-- For these we generate a subprogram declaration for library use,
-- and the corresponding entity does not come from source.
-- Nevertheless, all references will be attached to it and we have
-- to treat is as coming from user code.
and then (Comes_From_Source (E) or else Is_Child_Unit (E))
-- And must have a reasonable source location that is not
-- within an instance (all entities in instances are ignored)
and then Sloc (E) > No_Location
and then Instantiation_Location (Sloc (E)) = No_Location
-- And must be a non-internal name from the main source unit
and then In_Extended_Main_Source_Unit (E)
and then not Is_Internal_Name (Chars (E))
then
Add_Entry
((Ent => E,
Loc => No_Location,
Typ => ' ',
Eun => Get_Source_Unit (Original_Location (Sloc (E))),
Lun => No_Unit,
Ref_Scope => Empty,
Ent_Scope => Empty),
Ent_Scope_File => No_Unit);
if In_Inlined_Body then
Set_Referenced (E);
end if;
end if;
end Generate_Definition;
---------------------------------
-- Generate_Operator_Reference --
---------------------------------
procedure Generate_Operator_Reference
(N : Node_Id;
T : Entity_Id)
is
begin
if not In_Extended_Main_Source_Unit (N) then
return;
end if;
-- If the operator is not a Standard operator, then we generate a real
-- reference to the user defined operator.
if Sloc (Entity (N)) /= Standard_Location then
Generate_Reference (Entity (N), N);
-- A reference to an implicit inequality operator is also a reference
-- to the user-defined equality.
if Nkind (N) = N_Op_Ne
and then not Comes_From_Source (Entity (N))
and then Present (Corresponding_Equality (Entity (N)))
then
Generate_Reference (Corresponding_Equality (Entity (N)), N);
end if;
-- For the case of Standard operators, we mark the result type as
-- referenced. This ensures that in the case where we are using a
-- derived operator, we mark an entity of the unit that implicitly
-- defines this operator as used. Otherwise we may think that no entity
-- of the unit is used. The actual entity marked as referenced is the
-- first subtype, which is the relevant user defined entity.
-- Note: we only do this for operators that come from source. The
-- generated code sometimes reaches for entities that do not need to be
-- explicitly visible (for example, when we expand the code for
-- comparing two record objects, the fields of the record may not be
-- visible).
elsif Comes_From_Source (N) then
Set_Referenced (First_Subtype (T));
end if;
end Generate_Operator_Reference;
---------------------------------
-- Generate_Prim_Op_References --
---------------------------------
procedure Generate_Prim_Op_References (Typ : Entity_Id) is
Base_T : Entity_Id;
Prim : Elmt_Id;
Prim_List : Elist_Id;
begin
-- Handle subtypes of synchronized types
if Ekind (Typ) = E_Protected_Subtype
or else Ekind (Typ) = E_Task_Subtype
then
Base_T := Etype (Typ);
else
Base_T := Typ;
end if;
-- References to primitive operations are only relevant for tagged types
if not Is_Tagged_Type (Base_T)
or else Is_Class_Wide_Type (Base_T)
then
return;
end if;
-- Ada 2005 (AI-345): For synchronized types generate reference to the
-- wrapper that allow us to dispatch calls through their implemented
-- abstract interface types.
-- The check for Present here is to protect against previously reported
-- critical errors.
Prim_List := Primitive_Operations (Base_T);
if No (Prim_List) then
return;
end if;
Prim := First_Elmt (Prim_List);
while Present (Prim) loop
-- If the operation is derived, get the original for cross-reference
-- reference purposes (it is the original for which we want the xref
-- and for which the comes_from_source test must be performed).
Generate_Reference
(Typ, Ultimate_Alias (Node (Prim)), 'p', Set_Ref => False);
Next_Elmt (Prim);
end loop;
end Generate_Prim_Op_References;
------------------------
-- Generate_Reference --
------------------------
procedure Generate_Reference
(E : Entity_Id;
N : Node_Id;
Typ : Character := 'r';
Set_Ref : Boolean := True;
Force : Boolean := False)
is
Actual_Typ : Character := Typ;
Call : Node_Id;
Def : Source_Ptr;
Ent : Entity_Id;
Ent_Scope : Entity_Id;
Formal : Entity_Id;
Kind : Entity_Kind;
Nod : Node_Id;
Ref : Source_Ptr;
Ref_Scope : Entity_Id;
function Get_Through_Renamings (E : Entity_Id) return Entity_Id;
-- Get the enclosing entity through renamings, which may come from
-- source or from the translation of generic instantiations.
function Is_On_LHS (Node : Node_Id) return Boolean;
-- Used to check if a node is on the left hand side of an assignment.
-- The following cases are handled:
--
-- Variable Node is a direct descendant of left hand side of an
-- assignment statement.
--
-- Prefix Of an indexed or selected component that is present in
-- a subtree rooted by an assignment statement. There is
-- no restriction of nesting of components, thus cases
-- such as A.B (C).D are handled properly. However a prefix
-- of a dereference (either implicit or explicit) is never
-- considered as on a LHS.
--
-- Out param Same as above cases, but OUT parameter
function OK_To_Set_Referenced return Boolean;
-- Returns True if the Referenced flag can be set. There are a few
-- exceptions where we do not want to set this flag, see body for
-- details of these exceptional cases.
---------------------------
-- Get_Through_Renamings --
---------------------------
function Get_Through_Renamings (E : Entity_Id) return Entity_Id is
begin
case Ekind (E) is
-- For subprograms we just need to check once if they are have a
-- Renamed_Entity, because Renamed_Entity is set transitively.
when Subprogram_Kind =>
declare
Renamed : constant Entity_Id := Renamed_Entity (E);
begin
if Present (Renamed) then
return Renamed;
else
return E;
end if;
end;
-- For objects we need to repeatedly call Renamed_Object, because
-- it is not transitive.
when Object_Kind =>
declare
Obj : Entity_Id := E;
begin
loop
pragma Assert (Present (Obj));
declare
Renamed : constant Entity_Id := Renamed_Object (Obj);
begin
if Present (Renamed) then
Obj := Get_Enclosing_Object (Renamed);
-- The renamed expression denotes a non-object,
-- e.g. function call, slicing of a function call,
-- pointer dereference, etc.
if No (Obj) then
return Empty;
end if;
else
return Obj;
end if;
end;
end loop;
end;
when others =>
return E;
end case;
end Get_Through_Renamings;
---------------
-- Is_On_LHS --
---------------
-- ??? There are several routines here and there that perform a similar
-- (but subtly different) computation, which should be factored:
-- Sem_Util.Is_LHS
-- Sem_Util.May_Be_Lvalue
-- Sem_Util.Known_To_Be_Assigned
-- Exp_Ch2.Expand_Entry_Parameter.In_Assignment_Context
-- Exp_Smem.Is_Out_Actual
function Is_On_LHS (Node : Node_Id) return Boolean is
N : Node_Id;
P : Node_Id;
K : Node_Kind;
begin
-- Only identifiers are considered, is this necessary???
if Nkind (Node) /= N_Identifier then
return False;
end if;
-- Immediate return if appeared as OUT parameter
if Kind = E_Out_Parameter then
return True;
end if;
-- Search for assignment statement subtree root
N := Node;
loop
P := Parent (N);
K := Nkind (P);
if K = N_Assignment_Statement then
return Name (P) = N;
-- Check whether the parent is a component and the current node is
-- its prefix, but return False if the current node has an access
-- type, as in that case the selected or indexed component is an
-- implicit dereference, and the LHS is the designated object, not
-- the access object.
-- ??? case of a slice assignment?
elsif (K = N_Selected_Component or else K = N_Indexed_Component)
and then Prefix (P) = N
then
-- Check for access type. First a special test, In some cases
-- this is called too early (see comments in Find_Direct_Name),
-- at a point where the tree is not fully typed yet. In that
-- case we may lack an Etype for N, and we can't check the
-- Etype. For now, we always return False in such a case,
-- but this is clearly not right in all cases ???
if No (Etype (N)) then
return False;
elsif Is_Access_Type (Etype (N)) then
return False;
-- Access type case dealt with, keep going
else
N := P;
end if;
-- All other cases, definitely not on left side
else
return False;
end if;
end loop;
end Is_On_LHS;
---------------------------
-- OK_To_Set_Referenced --
---------------------------
function OK_To_Set_Referenced return Boolean is
P : Node_Id;
begin
-- A reference from a pragma Unreferenced or pragma Unmodified or
-- pragma Warnings does not cause the Referenced flag to be set.
-- This avoids silly warnings about things being referenced and
-- not assigned when the only reference is from the pragma.
if Nkind (N) = N_Identifier then
P := Parent (N);
if Nkind (P) = N_Pragma_Argument_Association then
P := Parent (P);
if Nkind (P) = N_Pragma then
if Nam_In (Pragma_Name_Unmapped (P),
Name_Warnings,
Name_Unmodified,
Name_Unreferenced)
then
return False;
end if;
end if;
-- A reference to a formal in a named parameter association does
-- not make the formal referenced. Formals that are unused in the
-- subprogram body are properly flagged as such, even if calls
-- elsewhere use named notation.
elsif Nkind (P) = N_Parameter_Association
and then N = Selector_Name (P)
then
return False;
end if;
end if;
return True;
end OK_To_Set_Referenced;
-- Start of processing for Generate_Reference
begin
pragma Assert (Nkind (E) in N_Entity);
Find_Actual (N, Formal, Call);
if Present (Formal) then
Kind := Ekind (Formal);
else
Kind := E_Void;
end if;
-- Check for obsolescent reference to package ASCII. GNAT treats this
-- element of annex J specially since in practice, programs make a lot
-- of use of this feature, so we don't include it in the set of features
-- diagnosed when Warn_On_Obsolescent_Features mode is set. However we
-- are required to note it as a violation of the RM defined restriction.
if E = Standard_ASCII then
Check_Restriction (No_Obsolescent_Features, N);
end if;
-- Check for reference to entity marked with Is_Obsolescent
-- Note that we always allow obsolescent references in the compiler
-- itself and the run time, since we assume that we know what we are
-- doing in such cases. For example the calls in Ada.Characters.Handling
-- to its own obsolescent subprograms are just fine.
-- In any case we only generate warnings if we are in the extended main
-- source unit, and the entity itself is not in the extended main source
-- unit, since we assume the source unit itself knows what is going on
-- (and for sure we do not want silly warnings, e.g. on the end line of
-- an obsolescent procedure body).
if Is_Obsolescent (E)
and then not GNAT_Mode
and then not In_Extended_Main_Source_Unit (E)
and then In_Extended_Main_Source_Unit (N)
then
Check_Restriction (No_Obsolescent_Features, N);
if Warn_On_Obsolescent_Feature then
Output_Obsolescent_Entity_Warnings (N, E);
end if;
end if;
-- Warn if reference to Ada 2005 entity not in Ada 2005 mode. We only
-- detect real explicit references (modifications and references).
if Comes_From_Source (N)
and then Is_Ada_2005_Only (E)
and then Ada_Version < Ada_2005
and then Warn_On_Ada_2005_Compatibility
and then (Typ = 'm' or else Typ = 'r' or else Typ = 's')
then
Error_Msg_NE ("& is only defined in Ada 2005?y?", N, E);
end if;
-- Warn if reference to Ada 2012 entity not in Ada 2012 mode. We only
-- detect real explicit references (modifications and references).
if Comes_From_Source (N)
and then Is_Ada_2012_Only (E)
and then Ada_Version < Ada_2012
and then Warn_On_Ada_2012_Compatibility
and then (Typ = 'm' or else Typ = 'r')
then
Error_Msg_NE ("& is only defined in Ada 2012?y?", N, E);
end if;
-- Do not generate references if we are within a postcondition sub-
-- program, because the reference does not comes from source, and the
-- preanalysis of the aspect has already created an entry for the ALI
-- file at the proper source location.
if Chars (Current_Scope) = Name_uPostconditions then
return;
end if;
-- Never collect references if not in main source unit. However, we omit
-- this test if Typ is 'e' or 'k', since these entries are structural,
-- and it is useful to have them in units that reference packages as
-- well as units that define packages. We also omit the test for the
-- case of 'p' since we want to include inherited primitive operations
-- from other packages.
-- We also omit this test is this is a body reference for a subprogram
-- instantiation. In this case the reference is to the generic body,
-- which clearly need not be in the main unit containing the instance.
-- For the same reason we accept an implicit reference generated for
-- a default in an instance.
-- We also set the referenced flag in a generic package that is not in
-- then main source unit, when the variable is of a formal private type,
-- to warn in the instance if the corresponding type is not a fully
-- initialized type.
if not In_Extended_Main_Source_Unit (N) then
if Typ = 'e' or else
Typ = 'I' or else
Typ = 'p' or else
Typ = 'i' or else
Typ = 'k'
or else (Typ = 'b' and then Is_Generic_Instance (E))
-- Allow the generation of references to reads, writes and calls
-- in SPARK mode when the related context comes from an instance.
or else
(GNATprove_Mode
and then In_Extended_Main_Code_Unit (N)
and then (Typ = 'm' or else Typ = 'r' or else Typ = 's'))
then
null;
elsif In_Instance_Body
and then In_Extended_Main_Code_Unit (N)
and then Is_Generic_Type (Etype (E))
then
Set_Referenced (E);
return;
elsif Inside_A_Generic
and then Is_Generic_Type (Etype (E))
then
Set_Referenced (E);
return;
else
return;
end if;
end if;
-- For reference type p, the entity must be in main source unit
if Typ = 'p' and then not In_Extended_Main_Source_Unit (E) then
return;
end if;
-- Unless the reference is forced, we ignore references where the
-- reference itself does not come from source.
if not Force and then not Comes_From_Source (N) then
return;
end if;
-- Deal with setting entity as referenced, unless suppressed. Note that
-- we still do Set_Referenced on entities that do not come from source.
-- This situation arises when we have a source reference to a derived
-- operation, where the derived operation itself does not come from
-- source, but we still want to mark it as referenced, since we really
-- are referencing an entity in the corresponding package (this avoids
-- wrong complaints that the package contains no referenced entities).
if Set_Ref then
-- Assignable object appearing on left side of assignment or as
-- an out parameter.
if Is_Assignable (E)
and then Is_On_LHS (N)
and then Ekind (E) /= E_In_Out_Parameter
then
-- For objects that are renamings, just set as simply referenced
-- we do not try to do assignment type tracking in this case.
if Present (Renamed_Object (E)) then
Set_Referenced (E);
-- Out parameter case
elsif Kind = E_Out_Parameter then
-- If warning mode for all out parameters is set, or this is
-- the only warning parameter, then we want to mark this for
-- later warning logic by setting Referenced_As_Out_Parameter
if Warn_On_Modified_As_Out_Parameter (Formal) then
Set_Referenced_As_Out_Parameter (E, True);
Set_Referenced_As_LHS (E, False);
-- For OUT parameter not covered by the above cases, we simply
-- regard it as a normal reference (in this case we do not
-- want any of the warning machinery for out parameters).
else
Set_Referenced (E);
end if;
-- For the left hand of an assignment case, we do nothing here.
-- The processing for Analyze_Assignment_Statement will set the
-- Referenced_As_LHS flag.
else
null;
end if;
-- Check for a reference in a pragma that should not count as a
-- making the variable referenced for warning purposes.
elsif Is_Non_Significant_Pragma_Reference (N) then
null;
-- A reference in an attribute definition clause does not count as a
-- reference except for the case of Address. The reason that 'Address
-- is an exception is that it creates an alias through which the
-- variable may be referenced.
elsif Nkind (Parent (N)) = N_Attribute_Definition_Clause
and then Chars (Parent (N)) /= Name_Address
and then N = Name (Parent (N))
then
null;
-- Constant completion does not count as a reference
elsif Typ = 'c'
and then Ekind (E) = E_Constant
then
null;
-- Record representation clause does not count as a reference
elsif Nkind (N) = N_Identifier
and then Nkind (Parent (N)) = N_Record_Representation_Clause
then
null;
-- Discriminants do not need to produce a reference to record type
elsif Typ = 'd'
and then Nkind (Parent (N)) = N_Discriminant_Specification
then
null;
-- All other cases
else
-- Special processing for IN OUT parameters, where we have an
-- implicit assignment to a simple variable.
if Kind = E_In_Out_Parameter
and then Is_Assignable (E)
then
-- For sure this counts as a normal read reference
Set_Referenced (E);
Set_Last_Assignment (E, Empty);
-- We count it as being referenced as an out parameter if the
-- option is set to warn on all out parameters, except that we
-- have a special exclusion for an intrinsic subprogram, which
-- is most likely an instantiation of Unchecked_Deallocation
-- which we do not want to consider as an assignment since it
-- generates false positives. We also exclude the case of an
-- IN OUT parameter if the name of the procedure is Free,
-- since we suspect similar semantics.
if Warn_On_All_Unread_Out_Parameters
and then Is_Entity_Name (Name (Call))
and then not Is_Intrinsic_Subprogram (Entity (Name (Call)))
and then Chars (Name (Call)) /= Name_Free
then
Set_Referenced_As_Out_Parameter (E, True);
Set_Referenced_As_LHS (E, False);
end if;
-- Don't count a recursive reference within a subprogram as a
-- reference (that allows detection of a recursive subprogram
-- whose only references are recursive calls as unreferenced).
elsif Is_Subprogram (E)
and then E = Nearest_Dynamic_Scope (Current_Scope)
then
null;
-- Any other occurrence counts as referencing the entity
elsif OK_To_Set_Referenced then
Set_Referenced (E);
-- If variable, this is an OK reference after an assignment
-- so we can clear the Last_Assignment indication.
if Is_Assignable (E) then
Set_Last_Assignment (E, Empty);
end if;
end if;
end if;
-- Check for pragma Unreferenced given and reference is within
-- this source unit (occasion for possible warning to be issued).
-- Note that the entity may be marked as unreferenced by pragma
-- Unused.
if Has_Unreferenced (E)
and then In_Same_Extended_Unit (E, N)
then
-- A reference as a named parameter in a call does not count as a
-- violation of pragma Unreferenced for this purpose...
if Nkind (N) = N_Identifier
and then Nkind (Parent (N)) = N_Parameter_Association
and then Selector_Name (Parent (N)) = N
then
null;
-- ... Neither does a reference to a variable on the left side of
-- an assignment.
elsif Is_On_LHS (N) then
null;
-- Do not consider F'Result as a violation of pragma Unreferenced
-- since the attribute acts as an anonymous alias of the function
-- result and not as a real reference to the function.
elsif Ekind_In (E, E_Function, E_Generic_Function)
and then Is_Entity_Name (N)
and then Is_Attribute_Result (Parent (N))
then
null;
-- No warning if the reference is in a call that does not come
-- from source (e.g. a call to a controlled type primitive).
elsif not Comes_From_Source (Parent (N))
and then Nkind (Parent (N)) = N_Procedure_Call_Statement
then
null;
-- For entry formals, we want to place the warning message on the
-- corresponding entity in the accept statement. The current scope
-- is the body of the accept, so we find the formal whose name
-- matches that of the entry formal (there is no link between the
-- two entities, and the one in the accept statement is only used
-- for conformance checking).
elsif Ekind (Scope (E)) = E_Entry then
declare
BE : Entity_Id;
begin
BE := First_Entity (Current_Scope);
while Present (BE) loop
if Chars (BE) = Chars (E) then
if Has_Pragma_Unused (E) then
Error_Msg_NE -- CODEFIX
("??pragma Unused given for&!", N, BE);
else
Error_Msg_NE -- CODEFIX
("??pragma Unreferenced given for&!", N, BE);
end if;
exit;
end if;
Next_Entity (BE);
end loop;
end;
-- Here we issue the warning, since this is a real reference
elsif Has_Pragma_Unused (E) then
Error_Msg_NE -- CODEFIX
("??pragma Unused given for&!", N, E);
else
Error_Msg_NE -- CODEFIX
("??pragma Unreferenced given for&!", N, E);
end if;
end if;
-- If this is a subprogram instance, mark as well the internal
-- subprogram in the wrapper package, which may be a visible
-- compilation unit.
if Is_Overloadable (E)
and then Is_Generic_Instance (E)
and then Present (Alias (E))
then
Set_Referenced (Alias (E));
end if;
end if;
-- Generate reference if all conditions are met:
if
-- Cross referencing must be active
Opt.Xref_Active
-- The entity must be one for which we collect references
and then Xref_Entity_Letters (Ekind (E)) /= ' '
-- Both Sloc values must be set to something sensible
and then Sloc (E) > No_Location
and then Sloc (N) > No_Location
-- Ignore references from within an instance. The only exceptions to
-- this are default subprograms, for which we generate an implicit
-- reference and compilations in SPARK mode.
and then
(Instantiation_Location (Sloc (N)) = No_Location
or else Typ = 'i'
or else GNATprove_Mode)
-- Ignore dummy references
and then Typ /= ' '
then
if Nkind_In (N, N_Identifier,
N_Defining_Identifier,
N_Defining_Operator_Symbol,
N_Operator_Symbol,
N_Defining_Character_Literal)
or else Nkind (N) in N_Op
or else (Nkind (N) = N_Character_Literal
and then Sloc (Entity (N)) /= Standard_Location)
then
Nod := N;
elsif Nkind_In (N, N_Expanded_Name, N_Selected_Component) then
Nod := Selector_Name (N);
else
return;
end if;
-- Normal case of source entity comes from source
if Comes_From_Source (E) then
Ent := E;
-- Because a declaration may be generated for a subprogram body
-- without declaration in GNATprove mode, for inlining, some
-- parameters may end up being marked as not coming from source
-- although they are. Take these into account specially.
elsif GNATprove_Mode and then Is_Formal (E) then
Ent := E;
-- Entity does not come from source, but is a derived subprogram and
-- the derived subprogram comes from source (after one or more
-- derivations) in which case the reference is to parent subprogram.
elsif Is_Overloadable (E)
and then Present (Alias (E))
then
Ent := Alias (E);
while not Comes_From_Source (Ent) loop
if No (Alias (Ent)) then
return;
end if;
Ent := Alias (Ent);
end loop;
-- The internally created defining entity for a child subprogram
-- that has no previous spec has valid references.
elsif Is_Overloadable (E)
and then Is_Child_Unit (E)
then
Ent := E;
-- Ditto for the formals of such a subprogram
elsif Is_Overloadable (Scope (E))
and then Is_Child_Unit (Scope (E))
then
Ent := E;
-- Record components of discriminated subtypes or derived types must
-- be treated as references to the original component.
elsif Ekind (E) = E_Component
and then Comes_From_Source (Original_Record_Component (E))
then
Ent := Original_Record_Component (E);
-- If this is an expanded reference to a discriminant, recover the
-- original discriminant, which gets the reference.
elsif Ekind (E) = E_In_Parameter
and then Present (Discriminal_Link (E))
then
Ent := Discriminal_Link (E);
Set_Referenced (Ent);
-- Ignore reference to any other entity that is not from source
else
return;
end if;
-- In SPARK mode, consider the underlying entity renamed instead of
-- the renaming, which is needed to compute a valid set of effects
-- (reads, writes) for the enclosing subprogram.
if GNATprove_Mode then
Ent := Get_Through_Renamings (Ent);
-- If no enclosing object, then it could be a reference to any
-- location not tracked individually, like heap-allocated data.
-- Conservatively approximate this possibility by generating a
-- dereference, and return.
if No (Ent) then
if Actual_Typ = 'w' then
SPARK_Specific.Generate_Dereference (Nod, 'r');
SPARK_Specific.Generate_Dereference (Nod, 'w');
else
SPARK_Specific.Generate_Dereference (Nod, 'r');
end if;
return;
end if;
end if;
-- Record reference to entity
if Actual_Typ = 'p'
and then Is_Subprogram (Nod)
and then Present (Overridden_Operation (Nod))
then
Actual_Typ := 'P';
end if;
-- Comment needed here for special SPARK code ???
if GNATprove_Mode then
-- Ignore references to an entity which is a Part_Of single
-- concurrent object. Ideally we would prefer to add it as a
-- reference to the corresponding concurrent type, but it is quite
-- difficult (as such references are not currently added even for)
-- reads/writes of private protected components) and not worth the
-- effort.
if Ekind_In (Ent, E_Abstract_State, E_Constant, E_Variable)
and then Present (Encapsulating_State (Ent))
and then Is_Single_Concurrent_Object (Encapsulating_State (Ent))
then
return;
end if;
Ref := Sloc (Nod);
Def := Sloc (Ent);
Ref_Scope :=
SPARK_Specific.Enclosing_Subprogram_Or_Library_Package (Nod);
Ent_Scope :=
SPARK_Specific.Enclosing_Subprogram_Or_Library_Package (Ent);
-- Since we are reaching through renamings in SPARK mode, we may
-- end up with standard constants. Ignore those.
if Sloc (Ent_Scope) <= Standard_Location
or else Def <= Standard_Location
then
return;
end if;
Add_Entry
((Ent => Ent,
Loc => Ref,
Typ => Actual_Typ,
Eun => Get_Top_Level_Code_Unit (Def),
Lun => Get_Top_Level_Code_Unit (Ref),
Ref_Scope => Ref_Scope,
Ent_Scope => Ent_Scope),
Ent_Scope_File => Get_Top_Level_Code_Unit (Ent));
else
Ref := Original_Location (Sloc (Nod));
Def := Original_Location (Sloc (Ent));
-- If this is an operator symbol, skip the initial quote for
-- navigation purposes. This is not done for the end label,
-- where we want the actual position after the closing quote.
if Typ = 't' then
null;
elsif Nkind (N) = N_Defining_Operator_Symbol
or else Nkind (Nod) = N_Operator_Symbol
then
Ref := Ref + 1;
end if;
Add_Entry
((Ent => Ent,
Loc => Ref,
Typ => Actual_Typ,
Eun => Get_Source_Unit (Def),
Lun => Get_Source_Unit (Ref),
Ref_Scope => Empty,
Ent_Scope => Empty),
Ent_Scope_File => No_Unit);
-- Generate reference to the first private entity
if Typ = 'e'
and then Comes_From_Source (E)
and then Nkind (Ent) = N_Defining_Identifier
and then (Is_Package_Or_Generic_Package (Ent)
or else Is_Concurrent_Type (Ent))
and then Present (First_Private_Entity (E))
and then In_Extended_Main_Source_Unit (N)
then
-- Handle case in which the full-view and partial-view of the
-- first private entity are swapped.
declare
First_Private : Entity_Id := First_Private_Entity (E);
begin
if Is_Private_Type (First_Private)
and then Present (Full_View (First_Private))
then
First_Private := Full_View (First_Private);
end if;
Add_Entry
((Ent => Ent,
Loc => Sloc (First_Private),
Typ => 'E',
Eun => Get_Source_Unit (Def),
Lun => Get_Source_Unit (Ref),
Ref_Scope => Empty,
Ent_Scope => Empty),
Ent_Scope_File => No_Unit);
end;
end if;
end if;
end if;
end Generate_Reference;
-----------------------------------
-- Generate_Reference_To_Formals --
-----------------------------------
procedure Generate_Reference_To_Formals (E : Entity_Id) is
Formal : Entity_Id;
begin
if Is_Generic_Subprogram (E) then
Formal := First_Entity (E);
while Present (Formal)
and then not Is_Formal (Formal)
loop
Next_Entity (Formal);
end loop;
elsif Ekind (E) in Access_Subprogram_Kind then
Formal := First_Formal (Designated_Type (E));
else
Formal := First_Formal (E);
end if;
while Present (Formal) loop
if Ekind (Formal) = E_In_Parameter then
if Nkind (Parameter_Type (Parent (Formal))) = N_Access_Definition
then
Generate_Reference (E, Formal, '^', False);
else
Generate_Reference (E, Formal, '>', False);
end if;
elsif Ekind (Formal) = E_In_Out_Parameter then
Generate_Reference (E, Formal, '=', False);
else
Generate_Reference (E, Formal, '<', False);
end if;
Next_Formal (Formal);
end loop;
end Generate_Reference_To_Formals;
-------------------------------------------
-- Generate_Reference_To_Generic_Formals --
-------------------------------------------
procedure Generate_Reference_To_Generic_Formals (E : Entity_Id) is
Formal : Entity_Id;
begin
Formal := First_Entity (E);
while Present (Formal) loop
if Comes_From_Source (Formal) then
Generate_Reference (E, Formal, 'z', False);
end if;
Next_Entity (Formal);
end loop;
end Generate_Reference_To_Generic_Formals;
-------------
-- Get_Key --
-------------
function Get_Key (E : Xref_Entry_Number) return Xref_Entry_Number is
begin
return E;
end Get_Key;
----------------------------
-- Has_Deferred_Reference --
----------------------------
function Has_Deferred_Reference (Ent : Entity_Id) return Boolean is
begin
for J in Deferred_References.First .. Deferred_References.Last loop
if Deferred_References.Table (J).E = Ent then
return True;
end if;
end loop;
return False;
end Has_Deferred_Reference;
----------
-- Hash --
----------
function Hash (F : Xref_Entry_Number) return Header_Num is
-- It is unlikely to have two references to the same entity at the same
-- source location, so the hash function depends only on the Ent and Loc
-- fields.
XE : Xref_Entry renames Xrefs.Table (F);
type M is mod 2**32;
H : constant M := M (XE.Key.Ent) + 2 ** 7 * M (abs XE.Key.Loc);
-- It would be more natural to write:
--
-- H : constant M := M'Mod (XE.Key.Ent) + 2**7 * M'Mod (XE.Key.Loc);
--
-- But we can't use M'Mod, because it prevents bootstrapping with older
-- compilers. Loc can be negative, so we do "abs" before converting.
-- One day this can be cleaned up ???
begin
return Header_Num (H mod Num_Buckets);
end Hash;
-----------------
-- HT_Set_Next --
-----------------
procedure HT_Set_Next (E : Xref_Entry_Number; Next : Xref_Entry_Number) is
begin
Xrefs.Table (E).HTable_Next := Next;
end HT_Set_Next;
-------------
-- HT_Next --
-------------
function HT_Next (E : Xref_Entry_Number) return Xref_Entry_Number is
begin
return Xrefs.Table (E).HTable_Next;
end HT_Next;
----------------
-- Initialize --
----------------
procedure Initialize is
begin
Xrefs.Init;
end Initialize;
--------
-- Lt --
--------
function Lt (T1, T2 : Xref_Entry) return Boolean is
begin
-- First test: if entity is in different unit, sort by unit
if T1.Key.Eun /= T2.Key.Eun then
return Dependency_Num (T1.Key.Eun) < Dependency_Num (T2.Key.Eun);
-- Second test: within same unit, sort by entity Sloc
elsif T1.Def /= T2.Def then
return T1.Def < T2.Def;
-- Third test: sort definitions ahead of references
elsif T1.Key.Loc = No_Location then
return True;
elsif T2.Key.Loc = No_Location then
return False;
-- Fourth test: for same entity, sort by reference location unit
elsif T1.Key.Lun /= T2.Key.Lun then
return Dependency_Num (T1.Key.Lun) < Dependency_Num (T2.Key.Lun);
-- Fifth test: order of location within referencing unit
elsif T1.Key.Loc /= T2.Key.Loc then
return T1.Key.Loc < T2.Key.Loc;
-- Finally, for two locations at the same address, we prefer
-- the one that does NOT have the type 'r' so that a modification
-- or extension takes preference, when there are more than one
-- reference at the same location. As a result, in the case of
-- entities that are in-out actuals, the read reference follows
-- the modify reference.
else
return T2.Key.Typ = 'r';
end if;
end Lt;
-----------------------
-- Output_References --
-----------------------
procedure Output_References is
procedure Get_Type_Reference
(Ent : Entity_Id;
Tref : out Entity_Id;
Left : out Character;
Right : out Character);
-- Given an Entity_Id Ent, determines whether a type reference is
-- required. If so, Tref is set to the entity for the type reference
-- and Left and Right are set to the left/right brackets to be output
-- for the reference. If no type reference is required, then Tref is
-- set to Empty, and Left/Right are set to space.
procedure Output_Import_Export_Info (Ent : Entity_Id);
-- Output language and external name information for an interfaced
-- entity, using the format <language, external_name>.
------------------------
-- Get_Type_Reference --
------------------------
procedure Get_Type_Reference
(Ent : Entity_Id;
Tref : out Entity_Id;
Left : out Character;
Right : out Character)
is
Sav : Entity_Id;
begin
-- See if we have a type reference
Tref := Ent;
Left := '{';
Right := '}';
loop
Sav := Tref;
-- Processing for types
if Is_Type (Tref) then
-- Case of base type
if Base_Type (Tref) = Tref then
-- If derived, then get first subtype
if Tref /= Etype (Tref) then
Tref := First_Subtype (Etype (Tref));
-- Set brackets for derived type, but don't override
-- pointer case since the fact that something is a
-- pointer is more important.
if Left /= '(' then
Left := '<';
Right := '>';
end if;
-- If the completion of a private type is itself a derived
-- type, we need the parent of the full view.
elsif Is_Private_Type (Tref)
and then Present (Full_View (Tref))
and then Etype (Full_View (Tref)) /= Full_View (Tref)
then
Tref := Etype (Full_View (Tref));
if Left /= '(' then
Left := '<';
Right := '>';
end if;
-- If non-derived pointer, get directly designated type.
-- If the type has a full view, all references are on the
-- partial view that is seen first.
elsif Is_Access_Type (Tref) then
Tref := Directly_Designated_Type (Tref);
Left := '(';
Right := ')';
elsif Is_Private_Type (Tref)
and then Present (Full_View (Tref))
then
if Is_Access_Type (Full_View (Tref)) then
Tref := Directly_Designated_Type (Full_View (Tref));
Left := '(';
Right := ')';
-- If the full view is an array type, we also retrieve
-- the corresponding component type, because the ali
-- entry already indicates that this is an array.
elsif Is_Array_Type (Full_View (Tref)) then
Tref := Component_Type (Full_View (Tref));
Left := '(';
Right := ')';
end if;
-- If non-derived array, get component type. Skip component
-- type for case of String or Wide_String, saves worthwhile
-- space.
elsif Is_Array_Type (Tref)
and then Tref /= Standard_String
and then Tref /= Standard_Wide_String
then
Tref := Component_Type (Tref);
Left := '(';
Right := ')';
-- For other non-derived base types, nothing
else
exit;
end if;
-- For a subtype, go to ancestor subtype
else
Tref := Ancestor_Subtype (Tref);
-- If no ancestor subtype, go to base type
if No (Tref) then
Tref := Base_Type (Sav);
end if;
end if;
-- For objects, functions, enum literals, just get type from
-- Etype field.
elsif Is_Object (Tref)
or else Ekind (Tref) = E_Enumeration_Literal
or else Ekind (Tref) = E_Function
or else Ekind (Tref) = E_Operator
then
Tref := Etype (Tref);
-- Another special case: an object of a classwide type
-- initialized with a tag-indeterminate call gets a subtype
-- of the classwide type during expansion. See if the original
-- type in the declaration is named, and return it instead
-- of going to the root type. The expression may be a class-
-- wide function call whose result is on the secondary stack,
-- which forces the declaration to be rewritten as a renaming,
-- so examine the source declaration.
if Ekind (Tref) = E_Class_Wide_Subtype then
declare
Decl : constant Node_Id := Original_Node (Parent (Ent));
begin
if Nkind (Decl) = N_Object_Declaration
and then Is_Entity_Name
(Original_Node (Object_Definition (Decl)))
then
Tref :=
Entity (Original_Node (Object_Definition (Decl)));
end if;
end;
-- For a function that returns a class-wide type, Tref is
-- already correct.
elsif Is_Overloadable (Ent)
and then Is_Class_Wide_Type (Tref)
then
return;
end if;
-- For anything else, exit
else
exit;
end if;
-- Exit if no type reference, or we are stuck in some loop trying
-- to find the type reference, or if the type is standard void
-- type (the latter is an implementation artifact that should not
-- show up in the generated cross-references).
exit when No (Tref)
or else Tref = Sav
or else Tref = Standard_Void_Type;
-- If we have a usable type reference, return, otherwise keep
-- looking for something useful (we are looking for something
-- that either comes from source or standard)
if Sloc (Tref) = Standard_Location
or else Comes_From_Source (Tref)
then
-- If the reference is a subtype created for a generic actual,
-- go actual directly, the inner subtype is not user visible.
if Nkind (Parent (Tref)) = N_Subtype_Declaration
and then not Comes_From_Source (Parent (Tref))
and then
(Is_Wrapper_Package (Scope (Tref))
or else Is_Generic_Instance (Scope (Tref)))
then
Tref := First_Subtype (Base_Type (Tref));
end if;
return;
end if;
end loop;
-- If we fall through the loop, no type reference
Tref := Empty;
Left := ' ';
Right := ' ';
end Get_Type_Reference;
-------------------------------
-- Output_Import_Export_Info --
-------------------------------
procedure Output_Import_Export_Info (Ent : Entity_Id) is
Language_Name : Name_Id;
Conv : constant Convention_Id := Convention (Ent);
begin
-- Generate language name from convention
if Conv = Convention_C then
Language_Name := Name_C;
elsif Conv = Convention_CPP then
Language_Name := Name_CPP;
elsif Conv = Convention_Ada then
Language_Name := Name_Ada;
else
-- For the moment we ignore all other cases ???
return;
end if;
Write_Info_Char ('<');
Get_Unqualified_Name_String (Language_Name);
for J in 1 .. Name_Len loop
Write_Info_Char (Name_Buffer (J));
end loop;
if Present (Interface_Name (Ent)) then
Write_Info_Char (',');
String_To_Name_Buffer (Strval (Interface_Name (Ent)));
for J in 1 .. Name_Len loop
Write_Info_Char (Name_Buffer (J));
end loop;
end if;
Write_Info_Char ('>');
end Output_Import_Export_Info;
-- Start of processing for Output_References
begin
-- First we add references to the primitive operations of tagged types
-- declared in the main unit.
Handle_Prim_Ops : declare
Ent : Entity_Id;
begin
for J in 1 .. Xrefs.Last loop
Ent := Xrefs.Table (J).Key.Ent;
if Is_Type (Ent)
and then Is_Tagged_Type (Ent)
and then Is_Base_Type (Ent)
and then In_Extended_Main_Source_Unit (Ent)
then
Generate_Prim_Op_References (Ent);
end if;
end loop;
end Handle_Prim_Ops;
-- Before we go ahead and output the references we have a problem
-- that needs dealing with. So far we have captured things that are
-- definitely referenced by the main unit, or defined in the main
-- unit. That's because we don't want to clutter up the ali file
-- for this unit with definition lines for entities in other units
-- that are not referenced.
-- But there is a glitch. We may reference an entity in another unit,
-- and it may have a type reference to an entity that is not directly
-- referenced in the main unit, which may mean that there is no xref
-- entry for this entity yet in the list of references.
-- If we don't do something about this, we will end with an orphan type
-- reference, i.e. it will point to an entity that does not appear
-- within the generated references in the ali file. That is not good for
-- tools using the xref information.
-- To fix this, we go through the references adding definition entries
-- for any unreferenced entities that can be referenced in a type
-- reference. There is a recursion problem here, and that is dealt with
-- by making sure that this traversal also traverses any entries that
-- get added by the traversal.
Handle_Orphan_Type_References : declare
J : Nat;
Tref : Entity_Id;
Ent : Entity_Id;
L, R : Character;
pragma Warnings (Off, L);
pragma Warnings (Off, R);
procedure New_Entry (E : Entity_Id);
-- Make an additional entry into the Xref table for a type entity
-- that is related to the current entity (parent, type ancestor,
-- progenitor, etc.).
----------------
-- New_Entry --
----------------
procedure New_Entry (E : Entity_Id) is
begin
pragma Assert (Present (E));
if not Has_Xref_Entry (Implementation_Base_Type (E))
and then Sloc (E) > No_Location
then
Add_Entry
((Ent => E,
Loc => No_Location,
Typ => Character'First,
Eun => Get_Source_Unit (Original_Location (Sloc (E))),
Lun => No_Unit,
Ref_Scope => Empty,
Ent_Scope => Empty),
Ent_Scope_File => No_Unit);
end if;
end New_Entry;
-- Start of processing for Handle_Orphan_Type_References
begin
-- Note that this is not a for loop for a very good reason. The
-- processing of items in the table can add new items to the table,
-- and they must be processed as well.
J := 1;
while J <= Xrefs.Last loop
Ent := Xrefs.Table (J).Key.Ent;
-- Do not generate reference information for an ignored Ghost
-- entity because neither the entity nor its references will
-- appear in the final tree.
if Is_Ignored_Ghost_Entity (Ent) then
goto Orphan_Continue;
end if;
Get_Type_Reference (Ent, Tref, L, R);
if Present (Tref)
and then not Has_Xref_Entry (Tref)
and then Sloc (Tref) > No_Location
then
New_Entry (Tref);
if Is_Record_Type (Ent)
and then Present (Interfaces (Ent))
then
-- Add an entry for each one of the given interfaces
-- implemented by type Ent.
declare
Elmt : Elmt_Id := First_Elmt (Interfaces (Ent));
begin
while Present (Elmt) loop
New_Entry (Node (Elmt));
Next_Elmt (Elmt);
end loop;
end;
end if;
end if;
-- Collect inherited primitive operations that may be declared in
-- another unit and have no visible reference in the current one.
if Is_Type (Ent)
and then Is_Tagged_Type (Ent)
and then Is_Derived_Type (Ent)
and then Is_Base_Type (Ent)
and then In_Extended_Main_Source_Unit (Ent)
then
declare
Op_List : constant Elist_Id := Primitive_Operations (Ent);
Op : Elmt_Id;
Prim : Entity_Id;
function Parent_Op (E : Entity_Id) return Entity_Id;
-- Find original operation, which may be inherited through
-- several derivations.
function Parent_Op (E : Entity_Id) return Entity_Id is
Orig_Op : constant Entity_Id := Alias (E);
begin
if No (Orig_Op) then
return Empty;
elsif not Comes_From_Source (E)
and then not Has_Xref_Entry (Orig_Op)
and then Comes_From_Source (Orig_Op)
then
return Orig_Op;
else
return Parent_Op (Orig_Op);
end if;
end Parent_Op;
begin
Op := First_Elmt (Op_List);
while Present (Op) loop
Prim := Parent_Op (Node (Op));
if Present (Prim) then
Add_Entry
((Ent => Prim,
Loc => No_Location,
Typ => Character'First,
Eun => Get_Source_Unit (Sloc (Prim)),
Lun => No_Unit,
Ref_Scope => Empty,
Ent_Scope => Empty),
Ent_Scope_File => No_Unit);
end if;
Next_Elmt (Op);
end loop;
end;
end if;
<<Orphan_Continue>>
J := J + 1;
end loop;
end Handle_Orphan_Type_References;
-- Now we have all the references, including those for any embedded type
-- references, so we can sort them, and output them.
Output_Refs : declare
Nrefs : constant Nat := Xrefs.Last;
-- Number of references in table
Rnums : array (0 .. Nrefs) of Nat;
-- This array contains numbers of references in the Xrefs table.
-- This list is sorted in output order. The extra 0'th entry is
-- convenient for the call to sort. When we sort the table, we
-- move the entries in Rnums around, but we do not move the
-- original table entries.
Curxu : Unit_Number_Type;
-- Current xref unit
Curru : Unit_Number_Type;
-- Current reference unit for one entity
Curent : Entity_Id;
-- Current entity
Curnam : String (1 .. Name_Buffer'Length);
Curlen : Natural;
-- Simple name and length of current entity
Curdef : Source_Ptr;
-- Original source location for current entity
Crloc : Source_Ptr;
-- Current reference location
Ctyp : Character;
-- Entity type character
Prevt : Character;
-- reference kind of previous reference
Tref : Entity_Id;
-- Type reference
Rref : Node_Id;
-- Renaming reference
Trunit : Unit_Number_Type;
-- Unit number for type reference
function Lt (Op1, Op2 : Natural) return Boolean;
-- Comparison function for Sort call
function Name_Change (X : Entity_Id) return Boolean;
-- Determines if entity X has a different simple name from Curent
procedure Move (From : Natural; To : Natural);
-- Move procedure for Sort call
package Sorting is new GNAT.Heap_Sort_G (Move, Lt);
--------
-- Lt --
--------
function Lt (Op1, Op2 : Natural) return Boolean is
T1 : Xref_Entry renames Xrefs.Table (Rnums (Nat (Op1)));
T2 : Xref_Entry renames Xrefs.Table (Rnums (Nat (Op2)));
begin
return Lt (T1, T2);
end Lt;
----------
-- Move --
----------
procedure Move (From : Natural; To : Natural) is
begin
Rnums (Nat (To)) := Rnums (Nat (From));
end Move;
-----------------
-- Name_Change --
-----------------
-- Why a string comparison here??? Why not compare Name_Id values???
function Name_Change (X : Entity_Id) return Boolean is
begin
Get_Unqualified_Name_String (Chars (X));
if Name_Len /= Curlen then
return True;
else
return Name_Buffer (1 .. Curlen) /= Curnam (1 .. Curlen);
end if;
end Name_Change;
-- Start of processing for Output_Refs
begin
-- Capture the definition Sloc values. We delay doing this till now,
-- since at the time the reference or definition is made, private
-- types may be swapped, and the Sloc value may be incorrect. We
-- also set up the pointer vector for the sort.
-- For user-defined operators we need to skip the initial quote and
-- point to the first character of the name, for navigation purposes.
for J in 1 .. Nrefs loop
declare
E : constant Entity_Id := Xrefs.Table (J).Key.Ent;
Loc : constant Source_Ptr := Original_Location (Sloc (E));
begin
Rnums (J) := J;
if Nkind (E) = N_Defining_Operator_Symbol then
Xrefs.Table (J).Def := Loc + 1;
else
Xrefs.Table (J).Def := Loc;
end if;
end;
end loop;
-- Sort the references
Sorting.Sort (Integer (Nrefs));
-- Initialize loop through references
Curxu := No_Unit;
Curent := Empty;
Curdef := No_Location;
Curru := No_Unit;
Crloc := No_Location;
Prevt := 'm';
-- Loop to output references
for Refno in 1 .. Nrefs loop
Output_One_Ref : declare
Ent : Entity_Id;
XE : Xref_Entry renames Xrefs.Table (Rnums (Refno));
-- The current entry to be accessed
Left : Character;
Right : Character;
-- Used for {} or <> or () for type reference
procedure Check_Type_Reference
(Ent : Entity_Id;
List_Interface : Boolean;
Is_Component : Boolean := False);
-- Find whether there is a meaningful type reference for
-- Ent, and display it accordingly. If List_Interface is
-- true, then Ent is a progenitor interface of the current
-- type entity being listed. In that case list it as is,
-- without looking for a type reference for it. Flag is also
-- used for index types of an array type, where the caller
-- supplies the intended type reference. Is_Component serves
-- the same purpose, to display the component type of a
-- derived array type, for which only the parent type has
-- ben displayed so far.
procedure Output_Instantiation_Refs (Loc : Source_Ptr);
-- Recursive procedure to output instantiation references for
-- the given source ptr in [file|line[...]] form. No output
-- if the given location is not a generic template reference.
procedure Output_Overridden_Op (Old_E : Entity_Id);
-- For a subprogram that is overriding, display information
-- about the inherited operation that it overrides.
--------------------------
-- Check_Type_Reference --
--------------------------
procedure Check_Type_Reference
(Ent : Entity_Id;
List_Interface : Boolean;
Is_Component : Boolean := False)
is
begin
if List_Interface then
-- This is a progenitor interface of the type for which
-- xref information is being generated.
Tref := Ent;
Left := '<';
Right := '>';
-- The following is not documented in lib-xref.ads ???
elsif Is_Component then
Tref := Ent;
Left := '(';
Right := ')';
else
Get_Type_Reference (Ent, Tref, Left, Right);
end if;
if Present (Tref) then
-- Case of standard entity, output name
if Sloc (Tref) = Standard_Location then
Write_Info_Char (Left);
Write_Info_Name (Chars (Tref));
Write_Info_Char (Right);
-- Case of source entity, output location
else
Write_Info_Char (Left);
Trunit := Get_Source_Unit (Sloc (Tref));
if Trunit /= Curxu then
Write_Info_Nat (Dependency_Num (Trunit));
Write_Info_Char ('|');
end if;
Write_Info_Nat
(Int (Get_Logical_Line_Number (Sloc (Tref))));
declare
Ent : Entity_Id;
Ctyp : Character;
begin
Ent := Tref;
Ctyp := Xref_Entity_Letters (Ekind (Ent));
if Ctyp = '+'
and then Present (Full_View (Ent))
then
Ent := Underlying_Type (Ent);
if Present (Ent) then
Ctyp := Xref_Entity_Letters (Ekind (Ent));
end if;
end if;
Write_Info_Char (Ctyp);
end;
Write_Info_Nat
(Int (Get_Column_Number (Sloc (Tref))));
-- If the type comes from an instantiation, add the
-- corresponding info.
Output_Instantiation_Refs (Sloc (Tref));
Write_Info_Char (Right);
end if;
end if;
end Check_Type_Reference;
-------------------------------
-- Output_Instantiation_Refs --
-------------------------------
procedure Output_Instantiation_Refs (Loc : Source_Ptr) is
Iloc : constant Source_Ptr := Instantiation_Location (Loc);
Lun : Unit_Number_Type;
Cu : constant Unit_Number_Type := Curru;
begin
-- Nothing to do if this is not an instantiation
if Iloc = No_Location then
return;
end if;
-- Output instantiation reference
Write_Info_Char ('[');
Lun := Get_Source_Unit (Iloc);
if Lun /= Curru then
Curru := Lun;
Write_Info_Nat (Dependency_Num (Curru));
Write_Info_Char ('|');
end if;
Write_Info_Nat (Int (Get_Logical_Line_Number (Iloc)));
-- Recursive call to get nested instantiations
Output_Instantiation_Refs (Iloc);
-- Output final ] after call to get proper nesting
Write_Info_Char (']');
Curru := Cu;
return;
end Output_Instantiation_Refs;
--------------------------
-- Output_Overridden_Op --
--------------------------
procedure Output_Overridden_Op (Old_E : Entity_Id) is
Op : Entity_Id;
begin
-- The overridden operation has an implicit declaration
-- at the point of derivation. What we want to display
-- is the original operation, which has the actual body
-- (or abstract declaration) that is being overridden.
-- The overridden operation is not always set, e.g. when
-- it is a predefined operator.
if No (Old_E) then
return;
-- Follow alias chain if one is present
elsif Present (Alias (Old_E)) then
-- The subprogram may have been implicitly inherited
-- through several levels of derivation, so find the
-- ultimate (source) ancestor.
Op := Ultimate_Alias (Old_E);
-- Normal case of no alias present. We omit generated
-- primitives like tagged equality, that have no source
-- representation.
else
Op := Old_E;
end if;
if Present (Op)
and then Sloc (Op) /= Standard_Location
and then Comes_From_Source (Op)
then
declare
Loc : constant Source_Ptr := Sloc (Op);
Par_Unit : constant Unit_Number_Type :=
Get_Source_Unit (Loc);
begin
Write_Info_Char ('<');
if Par_Unit /= Curxu then
Write_Info_Nat (Dependency_Num (Par_Unit));
Write_Info_Char ('|');
end if;
Write_Info_Nat (Int (Get_Logical_Line_Number (Loc)));
Write_Info_Char ('p');
Write_Info_Nat (Int (Get_Column_Number (Loc)));
Write_Info_Char ('>');
end;
end if;
end Output_Overridden_Op;
-- Start of processing for Output_One_Ref
begin
Ent := XE.Key.Ent;
-- Do not generate reference information for an ignored Ghost
-- entity because neither the entity nor its references will
-- appear in the final tree.
if Is_Ignored_Ghost_Entity (Ent) then
goto Continue;
end if;
Ctyp := Xref_Entity_Letters (Ekind (Ent));
-- Skip reference if it is the only reference to an entity,
-- and it is an END line reference, and the entity is not in
-- the current extended source. This prevents junk entries
-- consisting only of packages with END lines, where no
-- entity from the package is actually referenced.
if XE.Key.Typ = 'e'
and then Ent /= Curent
and then (Refno = Nrefs
or else
Ent /= Xrefs.Table (Rnums (Refno + 1)).Key.Ent)
and then not In_Extended_Main_Source_Unit (Ent)
then
goto Continue;
end if;
-- For private type, get full view type
if Ctyp = '+'
and then Present (Full_View (XE.Key.Ent))
then
Ent := Underlying_Type (Ent);
if Present (Ent) then
Ctyp := Xref_Entity_Letters (Ekind (Ent));
end if;
end if;
-- Special exception for Boolean
if Ctyp = 'E' and then Is_Boolean_Type (Ent) then
Ctyp := 'B';
end if;
-- For variable reference, get corresponding type
if Ctyp = '*' then
Ent := Etype (XE.Key.Ent);
Ctyp := Fold_Lower (Xref_Entity_Letters (Ekind (Ent)));
-- If variable is private type, get full view type
if Ctyp = '+'
and then Present (Full_View (Etype (XE.Key.Ent)))
then
Ent := Underlying_Type (Etype (XE.Key.Ent));
if Present (Ent) then
Ctyp := Fold_Lower (Xref_Entity_Letters (Ekind (Ent)));
end if;
elsif Is_Generic_Type (Ent) then
-- If the type of the entity is a generic private type,
-- there is no usable full view, so retain the indication
-- that this is an object.
Ctyp := '*';
end if;
-- Special handling for access parameters and objects and
-- components of an anonymous access type.
if Ekind_In (Etype (XE.Key.Ent),
E_Anonymous_Access_Type,
E_Anonymous_Access_Subprogram_Type,
E_Anonymous_Access_Protected_Subprogram_Type)
then
if Is_Formal (XE.Key.Ent)
or else
Ekind_In
(XE.Key.Ent, E_Variable, E_Constant, E_Component)
then
Ctyp := 'p';
end if;
-- Special handling for Boolean
elsif Ctyp = 'e' and then Is_Boolean_Type (Ent) then
Ctyp := 'b';
end if;
end if;
-- Special handling for abstract types and operations
if Is_Overloadable (XE.Key.Ent)
and then Is_Abstract_Subprogram (XE.Key.Ent)
then
if Ctyp = 'U' then
Ctyp := 'x'; -- Abstract procedure
elsif Ctyp = 'V' then
Ctyp := 'y'; -- Abstract function
end if;
elsif Is_Type (XE.Key.Ent)
and then Is_Abstract_Type (XE.Key.Ent)
then
if Is_Interface (XE.Key.Ent) then
Ctyp := 'h';
elsif Ctyp = 'R' then
Ctyp := 'H'; -- Abstract type
end if;
end if;
-- Only output reference if interesting type of entity
if Ctyp = ' '
-- Suppress references to object definitions, used for local
-- references.
or else XE.Key.Typ = 'D'
or else XE.Key.Typ = 'I'
-- Suppress self references, except for bodies that act as
-- specs.
or else (XE.Key.Loc = XE.Def
and then
(XE.Key.Typ /= 'b'
or else not Is_Subprogram (XE.Key.Ent)))
-- Also suppress definitions of body formals (we only
-- treat these as references, and the references were
-- separately recorded).
or else (Is_Formal (XE.Key.Ent)
and then Present (Spec_Entity (XE.Key.Ent)))
then
null;
else
-- Start new Xref section if new xref unit
if XE.Key.Eun /= Curxu then
if Write_Info_Col > 1 then
Write_Info_EOL;
end if;
Curxu := XE.Key.Eun;
Write_Info_Initiate ('X');
Write_Info_Char (' ');
Write_Info_Nat (Dependency_Num (XE.Key.Eun));
Write_Info_Char (' ');
Write_Info_Name
(Reference_Name (Source_Index (XE.Key.Eun)));
end if;
-- Start new Entity line if new entity. Note that we
-- consider two entities the same if they have the same
-- name and source location. This causes entities in
-- instantiations to be treated as though they referred
-- to the template.
if No (Curent)
or else
(XE.Key.Ent /= Curent
and then
(Name_Change (XE.Key.Ent) or else XE.Def /= Curdef))
then
Curent := XE.Key.Ent;
Curdef := XE.Def;
Get_Unqualified_Name_String (Chars (XE.Key.Ent));
Curlen := Name_Len;
Curnam (1 .. Curlen) := Name_Buffer (1 .. Curlen);
if Write_Info_Col > 1 then
Write_Info_EOL;
end if;
-- Write column number information
Write_Info_Nat (Int (Get_Logical_Line_Number (XE.Def)));
Write_Info_Char (Ctyp);
Write_Info_Nat (Int (Get_Column_Number (XE.Def)));
-- Write level information
Write_Level_Info : declare
function Is_Visible_Generic_Entity
(E : Entity_Id) return Boolean;
-- Check whether E is declared in the visible part
-- of a generic package. For source navigation
-- purposes, treat this as a visible entity.
function Is_Private_Record_Component
(E : Entity_Id) return Boolean;
-- Check whether E is a non-inherited component of a
-- private extension. Even if the enclosing record is
-- public, we want to treat the component as private
-- for navigation purposes.
---------------------------------
-- Is_Private_Record_Component --
---------------------------------
function Is_Private_Record_Component
(E : Entity_Id) return Boolean
is
S : constant Entity_Id := Scope (E);
begin
return
Ekind (E) = E_Component
and then Nkind (Declaration_Node (S)) =
N_Private_Extension_Declaration
and then Original_Record_Component (E) = E;
end Is_Private_Record_Component;
-------------------------------
-- Is_Visible_Generic_Entity --
-------------------------------
function Is_Visible_Generic_Entity
(E : Entity_Id) return Boolean
is
Par : Node_Id;
begin
-- The Present check here is an error defense
if Present (Scope (E))
and then Ekind (Scope (E)) /= E_Generic_Package
then
return False;
end if;
Par := Parent (E);
while Present (Par) loop
if
Nkind (Par) = N_Generic_Package_Declaration
then
-- Entity is a generic formal
return False;
elsif
Nkind (Parent (Par)) = N_Package_Specification
then
return
Is_List_Member (Par)
and then List_Containing (Par) =
Visible_Declarations (Parent (Par));
else
Par := Parent (Par);
end if;
end loop;
return False;
end Is_Visible_Generic_Entity;
-- Start of processing for Write_Level_Info
begin
if Is_Hidden (Curent)
or else Is_Private_Record_Component (Curent)
then
Write_Info_Char (' ');
elsif
Is_Public (Curent)
or else Is_Visible_Generic_Entity (Curent)
then
Write_Info_Char ('*');
else
Write_Info_Char (' ');
end if;
end Write_Level_Info;
-- Output entity name. We use the occurrence from the
-- actual source program at the definition point.
declare
Ent_Name : constant String :=
Exact_Source_Name (Sloc (XE.Key.Ent));
begin
for C in Ent_Name'Range loop
Write_Info_Char (Ent_Name (C));
end loop;
end;
-- See if we have a renaming reference
if Is_Object (XE.Key.Ent)
and then Present (Renamed_Object (XE.Key.Ent))
then
Rref := Renamed_Object (XE.Key.Ent);
elsif Is_Overloadable (XE.Key.Ent)
and then Nkind (Parent (Declaration_Node (XE.Key.Ent)))
= N_Subprogram_Renaming_Declaration
then
Rref := Name (Parent (Declaration_Node (XE.Key.Ent)));
elsif Ekind (XE.Key.Ent) = E_Package
and then Nkind (Declaration_Node (XE.Key.Ent)) =
N_Package_Renaming_Declaration
then
Rref := Name (Declaration_Node (XE.Key.Ent));
else
Rref := Empty;
end if;
if Present (Rref) then
if Nkind (Rref) = N_Expanded_Name then
Rref := Selector_Name (Rref);
end if;
if Nkind (Rref) = N_Identifier
or else Nkind (Rref) = N_Operator_Symbol
then
null;
-- For renamed array components, use the array name
-- for the renamed entity, which reflect the fact that
-- in general the whole array is aliased.
elsif Nkind (Rref) = N_Indexed_Component then
if Nkind (Prefix (Rref)) = N_Identifier then
Rref := Prefix (Rref);
elsif Nkind (Prefix (Rref)) = N_Expanded_Name then
Rref := Selector_Name (Prefix (Rref));
else
Rref := Empty;
end if;
else
Rref := Empty;
end if;
end if;
-- Write out renaming reference if we have one
if Present (Rref) then
Write_Info_Char ('=');
Write_Info_Nat
(Int (Get_Logical_Line_Number (Sloc (Rref))));
Write_Info_Char (':');
Write_Info_Nat
(Int (Get_Column_Number (Sloc (Rref))));
end if;
-- Indicate that the entity is in the unit of the current
-- xref section.
Curru := Curxu;
-- Write out information about generic parent, if entity
-- is an instance.
if Is_Generic_Instance (XE.Key.Ent) then
declare
Gen_Par : constant Entity_Id :=
Generic_Parent
(Specification
(Unit_Declaration_Node
(XE.Key.Ent)));
Loc : constant Source_Ptr := Sloc (Gen_Par);
Gen_U : constant Unit_Number_Type :=
Get_Source_Unit (Loc);
begin
Write_Info_Char ('[');
if Curru /= Gen_U then
Write_Info_Nat (Dependency_Num (Gen_U));
Write_Info_Char ('|');
end if;
Write_Info_Nat
(Int (Get_Logical_Line_Number (Loc)));
Write_Info_Char (']');
end;
end if;
-- See if we have a type reference and if so output
Check_Type_Reference (XE.Key.Ent, False);
-- Additional information for types with progenitors,
-- including synchronized tagged types.
declare
Typ : constant Entity_Id := XE.Key.Ent;
Elmt : Elmt_Id;
begin
if Is_Record_Type (Typ)
and then Present (Interfaces (Typ))
then
Elmt := First_Elmt (Interfaces (Typ));
elsif Is_Concurrent_Type (Typ)
and then Present (Corresponding_Record_Type (Typ))
and then Present (
Interfaces (Corresponding_Record_Type (Typ)))
then
Elmt :=
First_Elmt (
Interfaces (Corresponding_Record_Type (Typ)));
else
Elmt := No_Elmt;
end if;
while Present (Elmt) loop
Check_Type_Reference (Node (Elmt), True);
Next_Elmt (Elmt);
end loop;
end;
-- For array types, list index types as well. (This is
-- not C, indexes have distinct types).
if Is_Array_Type (XE.Key.Ent) then
declare
A_Typ : constant Entity_Id := XE.Key.Ent;
Indx : Node_Id;
begin
-- If this is a derived array type, we have
-- output the parent type, so add the component
-- type now.
if Is_Derived_Type (A_Typ) then
Check_Type_Reference
(Component_Type (A_Typ), False, True);
end if;
-- Add references to index types.
Indx := First_Index (XE.Key.Ent);
while Present (Indx) loop
Check_Type_Reference
(First_Subtype (Etype (Indx)), True);
Next_Index (Indx);
end loop;
end;
end if;
-- If the entity is an overriding operation, write info
-- on operation that was overridden.
if Is_Subprogram (XE.Key.Ent)
and then Present (Overridden_Operation (XE.Key.Ent))
then
Output_Overridden_Op
(Overridden_Operation (XE.Key.Ent));
end if;
-- End of processing for entity output
Crloc := No_Location;
end if;
-- Output the reference if it is not as the same location
-- as the previous one, or it is a read-reference that
-- indicates that the entity is an in-out actual in a call.
if XE.Key.Loc /= No_Location
and then
(XE.Key.Loc /= Crloc
or else (Prevt = 'm' and then XE.Key.Typ = 'r'))
then
Crloc := XE.Key.Loc;
Prevt := XE.Key.Typ;
-- Start continuation if line full, else blank
if Write_Info_Col > 72 then
Write_Info_EOL;
Write_Info_Initiate ('.');
end if;
Write_Info_Char (' ');
-- Output file number if changed
if XE.Key.Lun /= Curru then
Curru := XE.Key.Lun;
Write_Info_Nat (Dependency_Num (Curru));
Write_Info_Char ('|');
end if;
Write_Info_Nat
(Int (Get_Logical_Line_Number (XE.Key.Loc)));
Write_Info_Char (XE.Key.Typ);
if Is_Overloadable (XE.Key.Ent) then
if (Is_Imported (XE.Key.Ent) and then XE.Key.Typ = 'b')
or else
(Is_Exported (XE.Key.Ent) and then XE.Key.Typ = 'i')
then
Output_Import_Export_Info (XE.Key.Ent);
end if;
end if;
Write_Info_Nat (Int (Get_Column_Number (XE.Key.Loc)));
Output_Instantiation_Refs (Sloc (XE.Key.Ent));
end if;
end if;
end Output_One_Ref;
<<Continue>>
null;
end loop;
Write_Info_EOL;
end Output_Refs;
end Output_References;
---------------------------------
-- Process_Deferred_References --
---------------------------------
procedure Process_Deferred_References is
begin
for J in Deferred_References.First .. Deferred_References.Last loop
declare
D : Deferred_Reference_Entry renames Deferred_References.Table (J);
begin
case Is_LHS (D.N) is
when Yes =>
Generate_Reference (D.E, D.N, 'm');
when No =>
Generate_Reference (D.E, D.N, 'r');
-- Not clear if Unknown can occur at this stage, but if it
-- does we will treat it as a normal reference.
when Unknown =>
Generate_Reference (D.E, D.N, 'r');
end case;
end;
end loop;
-- Clear processed entries from table
Deferred_References.Init;
end Process_Deferred_References;
-- Start of elaboration for Lib.Xref
begin
-- Reset is necessary because Elmt_Ptr does not default to Null_Ptr,
-- because it's not an access type.
Xref_Set.Reset;
end Lib.Xref;