1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
11 -- Copyright (C) 1998-2001, Free Software Foundation, Inc. --
13 -- GNAT is free software; you can redistribute it and/or modify it under --
14 -- terms of the GNU General Public License as published by the Free Soft- --
15 -- ware Foundation; either version 2, or (at your option) any later ver- --
16 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
17 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
18 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
19 -- for more details. You should have received a copy of the GNU General --
20 -- Public License distributed with GNAT; see file COPYING. If not, write --
21 -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
22 -- MA 02111-1307, USA. --
24 -- GNAT was originally developed by the GNAT team at New York University. --
25 -- It is now maintained by Ada Core Technologies Inc (http://www.gnat.com). --
27 ------------------------------------------------------------------------------
29 with Atree; use Atree;
30 with Csets; use Csets;
31 with Lib.Util; use Lib.Util;
32 with Namet; use Namet;
34 with Sinfo; use Sinfo;
35 with Sinput; use Sinput;
36 with Table; use Table;
37 with Widechar; use Widechar;
39 with GNAT.Heap_Sort_A;
41 package body Lib.Xref is
47 -- The Xref table is used to record references. The Loc field is set
48 -- to No_Location for a definition entry.
50 subtype Xref_Entry_Number is Int;
52 type Xref_Entry is record
54 -- Entity referenced (E parameter to Generate_Reference)
57 -- Original source location for entity being referenced. Note that
58 -- these values are used only during the output process, they are
59 -- not set when the entries are originally built. This is because
60 -- private entities can be swapped when the initial call is made.
63 -- Location of reference (Original_Location (Sloc field of N parameter
64 -- to Generate_Reference). Set to No_Location for the case of a
65 -- defining occurrence.
68 -- Reference type (Typ param to Generate_Reference)
70 Eun : Unit_Number_Type;
71 -- Unit number corresponding to Ent
73 Lun : Unit_Number_Type;
74 -- Unit number corresponding to Loc. Value is undefined and not
75 -- referenced if Loc is set to No_Location.
79 package Xrefs is new Table.Table (
80 Table_Component_Type => Xref_Entry,
81 Table_Index_Type => Int,
83 Table_Initial => Alloc.Xrefs_Initial,
84 Table_Increment => Alloc.Xrefs_Increment,
85 Table_Name => "Xrefs");
87 function Get_Xref_Index (E : Entity_Id) return Xref_Entry_Number;
88 -- Returns the Xref entry table index for entity E.
89 -- So : Xrefs.Table (Get_Xref_Index (E)).Ent = E
91 -------------------------
92 -- Generate_Definition --
93 -------------------------
95 procedure Generate_Definition (E : Entity_Id) is
100 pragma Assert (Nkind (E) in N_Entity);
102 -- Note that we do not test Xref_Entity_Letters here. It is too
103 -- early to do so, since we are often called before the entity
104 -- is fully constructed, so that the Ekind is still E_Void.
108 -- Definition must come from source
110 and then Comes_From_Source (E)
112 -- And must have a reasonable source location that is not
113 -- within an instance (all entities in instances are ignored)
115 and then Sloc (E) > No_Location
116 and then Instantiation_Location (Sloc (E)) = No_Location
118 -- And must be a non-internal name from the main source unit
120 and then In_Extended_Main_Source_Unit (E)
121 and then not Is_Internal_Name (Chars (E))
123 Xrefs.Increment_Last;
125 Loc := Original_Location (Sloc (E));
127 Xrefs.Table (Indx).Ent := E;
128 Xrefs.Table (Indx).Loc := No_Location;
129 Xrefs.Table (Indx).Eun := Get_Source_Unit (Loc);
130 Xrefs.Table (Indx).Lun := No_Unit;
132 end Generate_Definition;
134 ---------------------------------
135 -- Generate_Operator_Reference --
136 ---------------------------------
138 procedure Generate_Operator_Reference (N : Node_Id) is
140 if not In_Extended_Main_Source_Unit (N) then
144 -- If the operator is not a Standard operator, then we generate
145 -- a real reference to the user defined operator.
147 if Sloc (Entity (N)) /= Standard_Location then
148 Generate_Reference (Entity (N), N);
150 -- A reference to an implicit inequality operator is a also a
151 -- reference to the user-defined equality.
153 if Nkind (N) = N_Op_Ne
154 and then not Comes_From_Source (Entity (N))
155 and then Present (Corresponding_Equality (Entity (N)))
157 Generate_Reference (Corresponding_Equality (Entity (N)), N);
160 -- For the case of Standard operators, we mark the result type
161 -- as referenced. This ensures that in the case where we are
162 -- using a derived operator, we mark an entity of the unit that
163 -- implicitly defines this operator as used. Otherwise we may
164 -- think that no entity of the unit is used. The actual entity
165 -- marked as referenced is the first subtype, which is the user
166 -- defined entity that is relevant.
169 if Nkind (N) = N_Op_Eq
170 or else Nkind (N) = N_Op_Ne
171 or else Nkind (N) = N_Op_Le
172 or else Nkind (N) = N_Op_Lt
173 or else Nkind (N) = N_Op_Ge
174 or else Nkind (N) = N_Op_Gt
176 Set_Referenced (First_Subtype (Etype (Right_Opnd (N))));
178 Set_Referenced (First_Subtype (Etype (N)));
181 end Generate_Operator_Reference;
183 ------------------------
184 -- Generate_Reference --
185 ------------------------
187 procedure Generate_Reference
190 Typ : Character := 'r';
191 Set_Ref : Boolean := True;
192 Force : Boolean := False)
201 pragma Assert (Nkind (E) in N_Entity);
203 -- Never collect references if not in main source unit. However,
204 -- we omit this test if Typ is 'e', since these entries are
205 -- really structural, and it is useful to have them in units
206 -- that reference packages as well as units that define packages.
208 if not In_Extended_Main_Source_Unit (N)
214 -- Unless the reference is forced, we ignore references where
215 -- the reference itself does not come from Source.
217 if not Force and then not Comes_From_Source (N) then
221 -- Deal with setting entity as referenced, unless suppressed.
222 -- Note that we still do Set_Referenced on entities that do not
223 -- come from source. This situation arises when we have a source
224 -- reference to a derived operation, where the derived operation
225 -- itself does not come from source, but we still want to mark it
226 -- as referenced, since we really are referencing an entity in the
227 -- corresponding package (this avoids incorrect complaints that the
228 -- package contains no referenced entities).
233 -- If this is a subprogram instance, mark as well the internal
234 -- subprogram in the wrapper package, which may be a visible
237 if Is_Overloadable (E)
238 and then Is_Generic_Instance (E)
239 and then Present (Alias (E))
241 Set_Referenced (Alias (E));
245 -- Generate reference if all conditions are met:
248 -- Cross referencing must be active
252 -- The entity must be one for which we collect references
254 and then Xref_Entity_Letters (Ekind (E)) /= ' '
256 -- Both Sloc values must be set to something sensible
258 and then Sloc (E) > No_Location
259 and then Sloc (N) > No_Location
261 -- We ignore references from within an instance
263 and then Instantiation_Location (Sloc (N)) = No_Location
265 -- Ignore dummy references
269 if Nkind (N) = N_Identifier
271 Nkind (N) = N_Defining_Identifier
275 Nkind (N) = N_Defining_Operator_Symbol
277 (Nkind (N) = N_Character_Literal
278 and then Sloc (Entity (N)) /= Standard_Location)
280 Nkind (N) = N_Defining_Character_Literal
284 elsif Nkind (N) = N_Expanded_Name
286 Nkind (N) = N_Selected_Component
288 Nod := Selector_Name (N);
294 -- Normal case of source entity comes from source
296 if Comes_From_Source (E) then
299 -- Entity does not come from source, but is a derived subprogram
300 -- and the derived subprogram comes from source, in which case
301 -- the reference is to this parent subprogram.
303 elsif Is_Overloadable (E)
304 and then Present (Alias (E))
305 and then Comes_From_Source (Alias (E))
309 -- Ignore reference to any other source that is not from source
315 -- Record reference to entity
317 Ref := Original_Location (Sloc (Nod));
318 Def := Original_Location (Sloc (Ent));
320 Xrefs.Increment_Last;
323 Xrefs.Table (Indx).Loc := Ref;
324 Xrefs.Table (Indx).Typ := Typ;
325 Xrefs.Table (Indx).Eun := Get_Source_Unit (Def);
326 Xrefs.Table (Indx).Lun := Get_Source_Unit (Ref);
327 Xrefs.Table (Indx).Ent := Ent;
329 end Generate_Reference;
335 function Get_Xref_Index (E : Entity_Id) return Xref_Entry_Number is
337 for K in 1 .. Xrefs.Last loop
338 if Xrefs.Table (K).Ent = E then
343 -- not found, this happend if the entity is not in the compiled unit.
348 -----------------------
349 -- Output_References --
350 -----------------------
352 procedure Output_References is
353 Nrefs : constant Nat := Xrefs.Last;
355 Rnums : array (0 .. Nrefs) of Nat;
356 -- This array contains numbers of references in the Xrefs table. This
357 -- list is sorted in output order. The extra 0'th entry is convenient
358 -- for the call to sort. When we sort the table, we move these entries
359 -- around, but we do not move the original table entries.
361 function Lt (Op1, Op2 : Natural) return Boolean;
362 -- Comparison function for Sort call
364 procedure Move (From : Natural; To : Natural);
365 -- Move procedure for Sort call
367 function Lt (Op1, Op2 : Natural) return Boolean is
368 T1 : Xref_Entry renames Xrefs.Table (Rnums (Nat (Op1)));
369 T2 : Xref_Entry renames Xrefs.Table (Rnums (Nat (Op2)));
372 -- First test. If entity is in different unit, sort by unit
374 if T1.Eun /= T2.Eun then
375 return Dependency_Num (T1.Eun) < Dependency_Num (T2.Eun);
377 -- Second test, within same unit, sort by entity Sloc
379 elsif T1.Def /= T2.Def then
380 return T1.Def < T2.Def;
382 -- Third test, sort definitions ahead of references
384 elsif T1.Loc = No_Location then
387 elsif T2.Loc = No_Location then
390 -- Fourth test, for same entity, sort by reference location unit
392 elsif T1.Lun /= T2.Lun then
393 return Dependency_Num (T1.Lun) < Dependency_Num (T2.Lun);
395 -- Fifth test order of location within referencing unit
397 elsif T1.Loc /= T2.Loc then
398 return T1.Loc < T2.Loc;
400 -- Finally, for two locations at the same address, we prefer
401 -- the one that does NOT have the type 'r' so that a modification
402 -- or extension takes preference, when there are more than one
403 -- reference at the same location.
410 procedure Move (From : Natural; To : Natural) is
412 Rnums (Nat (To)) := Rnums (Nat (From));
415 -- Start of processing for Output_References
418 if not Opt.Xref_Active then
422 -- Capture the definition Sloc values. We delay doing this till now,
423 -- since at the time the reference or definition is made, private
424 -- types may be swapped, and the Sloc value may be incorrect. We
425 -- also set up the pointer vector for the sort.
427 for J in 1 .. Nrefs loop
429 Xrefs.Table (J).Def :=
430 Original_Location (Sloc (Xrefs.Table (J).Ent));
433 -- Sort the references
435 GNAT.Heap_Sort_A.Sort
437 Move'Unrestricted_Access,
438 Lt'Unrestricted_Access);
440 -- Now output the references
442 Output_Refs : declare
444 Curxu : Unit_Number_Type;
447 Curru : Unit_Number_Type;
448 -- Current reference unit for one entity
450 Cursrc : Source_Buffer_Ptr;
451 -- Current xref unit source text
456 Curnam : String (1 .. Name_Buffer'Length);
458 -- Simple name and length of current entity
461 -- Original source location for current entity
464 -- Current reference location
467 -- Entity type character
470 -- entry for parent of derived type.
472 function Name_Change (X : Entity_Id) return Boolean;
473 -- Determines if entity X has a different simple name from Curent
475 function Get_Parent_Entry (X : Entity_Id) return Int;
476 -- For a derived type, locate entry of parent type, if defined in
477 -- in the current unit.
479 function Get_Parent_Entry (X : Entity_Id) return Int is
480 Parent_Type : Entity_Id;
484 or else not Is_Derived_Type (X)
488 Parent_Type := First_Subtype (Etype (Base_Type (X)));
490 if Comes_From_Source (Parent_Type) then
491 return Get_Xref_Index (Parent_Type);
497 end Get_Parent_Entry;
499 function Name_Change (X : Entity_Id) return Boolean is
501 Get_Unqualified_Name_String (Chars (X));
503 if Name_Len /= Curlen then
507 return Name_Buffer (1 .. Curlen) /= Curnam (1 .. Curlen);
511 -- Start of processing for Output_Refs
516 Curdef := No_Location;
518 Crloc := No_Location;
520 for Refno in 1 .. Nrefs loop
522 XE : Xref_Entry renames Xrefs.Table (Rnums (Refno));
523 -- The current entry to be accessed
526 -- Used to index into source buffer to get entity name
535 Ctyp := Xref_Entity_Letters (Ekind (Ent));
537 -- Skip reference if it is the only reference to an entity,
538 -- and it is an end-line reference, and the entity is not in
539 -- the current extended source. This prevents junk entries
540 -- consisting only of packages with end lines, where no
541 -- entity from the package is actually referenced.
544 and then Ent /= Curent
545 and then (Refno = Nrefs or else
546 Ent /= Xrefs.Table (Rnums (Refno + 1)).Ent)
548 not In_Extended_Main_Source_Unit (Ent)
553 -- For private type, get full view type
556 and then Present (Full_View (XE.Ent))
558 Ent := Underlying_Type (Ent);
560 if Present (Ent) then
561 Ctyp := Xref_Entity_Letters (Ekind (Ent));
565 -- Special exception for Boolean
567 if Ctyp = 'E' and then Is_Boolean_Type (Ent) then
571 -- For variable reference, get corresponding type
574 Ent := Etype (XE.Ent);
575 Ctyp := Fold_Lower (Xref_Entity_Letters (Ekind (Ent)));
577 -- If variable is private type, get full view type
580 and then Present (Full_View (Etype (XE.Ent)))
582 Ent := Underlying_Type (Etype (XE.Ent));
584 if Present (Ent) then
585 Ctyp := Xref_Entity_Letters (Ekind (Ent));
589 -- Special handling for access parameter
591 if Ekind (Etype (XE.Ent)) = E_Anonymous_Access_Type
592 and then Is_Formal (XE.Ent)
596 -- Special handling for Boolean
598 elsif Ctyp = 'e' and then Is_Boolean_Type (Ent) then
603 -- Only output reference if interesting type of entity,
604 -- and suppress self references. Also suppress definitions
605 -- of body formals (we only treat these as references, and
606 -- the references were separately recorded).
609 and then XE.Loc /= XE.Def
610 and then (not Is_Formal (XE.Ent)
611 or else No (Spec_Entity (XE.Ent)))
613 -- Start new Xref section if new xref unit
615 if XE.Eun /= Curxu then
617 if Write_Info_Col > 1 then
622 Cursrc := Source_Text (Source_Index (Curxu));
624 Write_Info_Initiate ('X');
625 Write_Info_Char (' ');
626 Write_Info_Nat (Dependency_Num (XE.Eun));
627 Write_Info_Char (' ');
628 Write_Info_Name (Reference_Name (Source_Index (XE.Eun)));
631 -- Start new Entity line if new entity. Note that we
632 -- consider two entities the same if they have the same
633 -- name and source location. This causes entities in
634 -- instantiations to be treated as though they referred
641 (Name_Change (XE.Ent) or else XE.Def /= Curdef))
646 Get_Unqualified_Name_String (Chars (XE.Ent));
648 Curnam (1 .. Curlen) := Name_Buffer (1 .. Curlen);
650 if Write_Info_Col > 1 then
654 -- Write column number information
656 Write_Info_Nat (Int (Get_Logical_Line_Number (XE.Def)));
657 Write_Info_Char (Ctyp);
658 Write_Info_Nat (Int (Get_Column_Number (XE.Def)));
660 -- Write level information
662 if Is_Public (Curent) and then not Is_Hidden (Curent) then
663 Write_Info_Char ('*');
665 Write_Info_Char (' ');
668 -- Output entity name. We use the occurrence from the
669 -- actual source program at the definition point
671 P := Original_Location (Sloc (XE.Ent));
673 -- Entity is character literal
675 if Cursrc (P) = ''' then
676 Write_Info_Char (Cursrc (P));
677 Write_Info_Char (Cursrc (P + 1));
678 Write_Info_Char (Cursrc (P + 2));
680 -- Entity is operator symbol
682 elsif Cursrc (P) = '"' or else Cursrc (P) = '%' then
683 Write_Info_Char (Cursrc (P));
688 Write_Info_Char (Cursrc (P2));
689 exit when Cursrc (P2) = Cursrc (P);
692 -- Entity is identifier
696 if Is_Start_Of_Wide_Char (Cursrc, P) then
697 Scan_Wide (Cursrc, P, WC, Err);
698 elsif not Identifier_Char (Cursrc (P)) then
706 Original_Location (Sloc (XE.Ent)) .. P - 1
708 Write_Info_Char (Cursrc (J));
712 -- Output derived entity name if it is available
714 Parent_Entry := Get_Parent_Entry (XE.Ent);
716 if Parent_Entry /= 0 then
718 XD : Xref_Entry renames Xrefs.Table (Parent_Entry);
721 Write_Info_Char ('<');
723 -- Write unit number only if different from the
726 if XE.Eun /= XD.Eun then
727 Write_Info_Nat (Dependency_Num (XD.Eun));
728 Write_Info_Char ('|');
732 (Int (Get_Logical_Line_Number (XD.Def)));
734 (Xref_Entity_Letters (Ekind (XD.Ent)));
735 Write_Info_Nat (Int (Get_Column_Number (XD.Def)));
737 Write_Info_Char ('>');
742 Crloc := No_Location;
745 -- Output the reference
747 if XE.Loc /= No_Location
748 and then XE.Loc /= Crloc
752 -- Start continuation if line full, else blank
754 if Write_Info_Col > 72 then
756 Write_Info_Initiate ('.');
759 Write_Info_Char (' ');
761 -- Output file number if changed
763 if XE.Lun /= Curru then
765 Write_Info_Nat (Dependency_Num (Curru));
766 Write_Info_Char ('|');
769 Write_Info_Nat (Int (Get_Logical_Line_Number (XE.Loc)));
770 Write_Info_Char (XE.Typ);
771 Write_Info_Nat (Int (Get_Column_Number (XE.Loc)));
782 end Output_References;