111
|
1 ------------------------------------------------------------------------------
|
|
2 -- --
|
|
3 -- GNAT COMPILER COMPONENTS --
|
|
4 -- --
|
|
5 -- L I B . X R E F . S P A R K _ S P E C I F I C --
|
|
6 -- --
|
|
7 -- B o d y --
|
|
8 -- --
|
131
|
9 -- Copyright (C) 2011-2018, Free Software Foundation, Inc. --
|
111
|
10 -- --
|
|
11 -- GNAT is free software; you can redistribute it and/or modify it under --
|
|
12 -- terms of the GNU General Public License as published by the Free Soft- --
|
|
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
|
|
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
|
|
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
|
|
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
|
|
17 -- for more details. You should have received a copy of the GNU General --
|
|
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
|
|
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
|
|
20 -- --
|
|
21 -- GNAT was originally developed by the GNAT team at New York University. --
|
|
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
|
|
23 -- --
|
|
24 ------------------------------------------------------------------------------
|
|
25
|
|
26 with Einfo; use Einfo;
|
|
27 with Nmake; use Nmake;
|
|
28 with SPARK_Xrefs; use SPARK_Xrefs;
|
|
29
|
|
30 separate (Lib.Xref)
|
|
31 package body SPARK_Specific is
|
|
32
|
|
33 ---------------------
|
|
34 -- Local Constants --
|
|
35 ---------------------
|
|
36
|
|
37 -- Table of SPARK_Entities, True for each entity kind used in SPARK
|
|
38
|
|
39 SPARK_Entities : constant array (Entity_Kind) of Boolean :=
|
|
40 (E_Constant => True,
|
|
41 E_Entry => True,
|
|
42 E_Function => True,
|
|
43 E_In_Out_Parameter => True,
|
|
44 E_In_Parameter => True,
|
|
45 E_Loop_Parameter => True,
|
|
46 E_Operator => True,
|
|
47 E_Out_Parameter => True,
|
|
48 E_Procedure => True,
|
|
49 E_Variable => True,
|
|
50 others => False);
|
|
51
|
|
52 -- True for each reference type used in SPARK
|
|
53
|
|
54 SPARK_References : constant array (Character) of Boolean :=
|
|
55 ('m' => True,
|
|
56 'r' => True,
|
|
57 's' => True,
|
|
58 others => False);
|
|
59
|
|
60 ---------------------
|
|
61 -- Local Variables --
|
|
62 ---------------------
|
|
63
|
|
64 package Drefs is new Table.Table (
|
|
65 Table_Component_Type => Xref_Entry,
|
|
66 Table_Index_Type => Xref_Entry_Number,
|
|
67 Table_Low_Bound => 1,
|
|
68 Table_Initial => Alloc.Drefs_Initial,
|
|
69 Table_Increment => Alloc.Drefs_Increment,
|
|
70 Table_Name => "Drefs");
|
|
71 -- Table of cross-references for reads and writes through explicit
|
|
72 -- dereferences, that are output as reads/writes to the special variable
|
|
73 -- "Heap". These references are added to the regular references when
|
|
74 -- computing SPARK cross-references.
|
|
75
|
131
|
76 -------------------------
|
|
77 -- Iterate_SPARK_Xrefs --
|
|
78 -------------------------
|
111
|
79
|
131
|
80 procedure Iterate_SPARK_Xrefs is
|
111
|
81
|
131
|
82 procedure Add_SPARK_Xref (Index : Int; Xref : Xref_Entry);
|
111
|
83
|
|
84 function Is_SPARK_Reference
|
|
85 (E : Entity_Id;
|
|
86 Typ : Character) return Boolean;
|
|
87 -- Return whether entity reference E meets SPARK requirements. Typ is
|
|
88 -- the reference type.
|
|
89
|
|
90 function Is_SPARK_Scope (E : Entity_Id) return Boolean;
|
|
91 -- Return whether the entity or reference scope meets requirements for
|
|
92 -- being a SPARK scope.
|
|
93
|
131
|
94 --------------------
|
|
95 -- Add_SPARK_Xref --
|
|
96 --------------------
|
111
|
97
|
131
|
98 procedure Add_SPARK_Xref (Index : Int; Xref : Xref_Entry) is
|
|
99 Ref : Xref_Key renames Xref.Key;
|
111
|
100 begin
|
131
|
101 -- Eliminate entries not appropriate for SPARK
|
111
|
102
|
131
|
103 if SPARK_Entities (Ekind (Ref.Ent))
|
|
104 and then SPARK_References (Ref.Typ)
|
|
105 and then Is_SPARK_Scope (Ref.Ent_Scope)
|
|
106 and then Is_SPARK_Scope (Ref.Ref_Scope)
|
|
107 and then Is_SPARK_Reference (Ref.Ent, Ref.Typ)
|
|
108 then
|
|
109 Process
|
|
110 (Index,
|
|
111 (Entity => Ref.Ent,
|
|
112 Ref_Scope => Ref.Ref_Scope,
|
|
113 Rtype => Ref.Typ));
|
|
114 end if;
|
111
|
115
|
131
|
116 end Add_SPARK_Xref;
|
111
|
117
|
|
118 ------------------------
|
|
119 -- Is_SPARK_Reference --
|
|
120 ------------------------
|
|
121
|
|
122 function Is_SPARK_Reference
|
|
123 (E : Entity_Id;
|
|
124 Typ : Character) return Boolean
|
|
125 is
|
|
126 begin
|
|
127 -- The only references of interest on callable entities are calls. On
|
|
128 -- uncallable entities, the only references of interest are reads and
|
|
129 -- writes.
|
|
130
|
|
131 if Ekind (E) in Overloadable_Kind then
|
|
132 return Typ = 's';
|
|
133
|
|
134 -- In all other cases, result is true for reference/modify cases,
|
|
135 -- and false for all other cases.
|
|
136
|
|
137 else
|
|
138 return Typ = 'r' or else Typ = 'm';
|
|
139 end if;
|
|
140 end Is_SPARK_Reference;
|
|
141
|
|
142 --------------------
|
|
143 -- Is_SPARK_Scope --
|
|
144 --------------------
|
|
145
|
|
146 function Is_SPARK_Scope (E : Entity_Id) return Boolean is
|
|
147 Can_Be_Renamed : constant Boolean :=
|
|
148 Present (E)
|
|
149 and then (Is_Subprogram_Or_Entry (E)
|
|
150 or else Ekind (E) = E_Package);
|
|
151 begin
|
|
152 return Present (E)
|
|
153 and then not Is_Generic_Unit (E)
|
131
|
154 and then (not Can_Be_Renamed or else No (Renamed_Entity (E)));
|
111
|
155 end Is_SPARK_Scope;
|
|
156
|
|
157 -- Start of processing for Add_SPARK_Xrefs
|
|
158
|
|
159 begin
|
131
|
160 -- Expose cross-references from private frontend tables to the backend
|
111
|
161
|
131
|
162 for Index in Drefs.First .. Drefs.Last loop
|
|
163 Add_SPARK_Xref (Index, Drefs.Table (Index));
|
111
|
164 end loop;
|
|
165
|
131
|
166 for Index in Xrefs.First .. Xrefs.Last loop
|
|
167 Add_SPARK_Xref (-Index, Xrefs.Table (Index));
|
111
|
168 end loop;
|
131
|
169 end Iterate_SPARK_Xrefs;
|
111
|
170
|
131
|
171 ---------------------------------------------
|
|
172 -- Enclosing_Subprogram_Or_Library_Package --
|
|
173 ---------------------------------------------
|
111
|
174
|
|
175 function Enclosing_Subprogram_Or_Library_Package
|
|
176 (N : Node_Id) return Entity_Id
|
|
177 is
|
|
178 Context : Entity_Id;
|
|
179
|
|
180 begin
|
|
181 -- If N is the defining identifier for a subprogram, then return the
|
|
182 -- enclosing subprogram or package, not this subprogram.
|
|
183
|
|
184 if Nkind_In (N, N_Defining_Identifier, N_Defining_Operator_Symbol)
|
|
185 and then (Ekind (N) in Entry_Kind
|
|
186 or else Ekind (N) = E_Subprogram_Body
|
|
187 or else Ekind (N) in Generic_Subprogram_Kind
|
|
188 or else Ekind (N) in Subprogram_Kind)
|
|
189 then
|
|
190 Context := Parent (Unit_Declaration_Node (N));
|
|
191
|
|
192 -- If this was a library-level subprogram then replace Context with
|
|
193 -- its Unit, which points to N_Subprogram_* node.
|
|
194
|
|
195 if Nkind (Context) = N_Compilation_Unit then
|
|
196 Context := Unit (Context);
|
|
197 end if;
|
|
198 else
|
|
199 Context := N;
|
|
200 end if;
|
|
201
|
|
202 while Present (Context) loop
|
|
203 case Nkind (Context) is
|
|
204 when N_Package_Body
|
|
205 | N_Package_Specification
|
|
206 =>
|
|
207 -- Only return a library-level package
|
|
208
|
|
209 if Is_Library_Level_Entity (Defining_Entity (Context)) then
|
|
210 Context := Defining_Entity (Context);
|
|
211 exit;
|
|
212 else
|
|
213 Context := Parent (Context);
|
|
214 end if;
|
|
215
|
|
216 when N_Pragma =>
|
|
217
|
|
218 -- The enclosing subprogram for a precondition, postcondition,
|
|
219 -- or contract case should be the declaration preceding the
|
|
220 -- pragma (skipping any other pragmas between this pragma and
|
|
221 -- this declaration.
|
|
222
|
|
223 while Nkind (Context) = N_Pragma
|
|
224 and then Is_List_Member (Context)
|
|
225 and then Present (Prev (Context))
|
|
226 loop
|
|
227 Context := Prev (Context);
|
|
228 end loop;
|
|
229
|
|
230 if Nkind (Context) = N_Pragma then
|
131
|
231
|
|
232 -- When used for cross-references then aspects might not be
|
|
233 -- yet linked to pragmas; when used for AST navigation in
|
|
234 -- GNATprove this routine is expected to follow those links.
|
|
235
|
|
236 if From_Aspect_Specification (Context) then
|
|
237 Context := Corresponding_Aspect (Context);
|
|
238 pragma Assert (Nkind (Context) = N_Aspect_Specification);
|
|
239 Context := Entity (Context);
|
|
240 else
|
|
241 Context := Parent (Context);
|
|
242 end if;
|
111
|
243 end if;
|
|
244
|
|
245 when N_Entry_Body
|
|
246 | N_Entry_Declaration
|
|
247 | N_Protected_Type_Declaration
|
|
248 | N_Subprogram_Body
|
|
249 | N_Subprogram_Declaration
|
|
250 | N_Subprogram_Specification
|
|
251 | N_Task_Body
|
|
252 | N_Task_Type_Declaration
|
|
253 =>
|
|
254 Context := Defining_Entity (Context);
|
|
255 exit;
|
|
256
|
|
257 when others =>
|
|
258 Context := Parent (Context);
|
|
259 end case;
|
|
260 end loop;
|
|
261
|
|
262 if Nkind (Context) = N_Defining_Program_Unit_Name then
|
|
263 Context := Defining_Identifier (Context);
|
|
264 end if;
|
|
265
|
|
266 -- Do not return a scope without a proper location
|
|
267
|
|
268 if Present (Context)
|
|
269 and then Sloc (Context) = No_Location
|
|
270 then
|
|
271 return Empty;
|
|
272 end if;
|
|
273
|
|
274 return Context;
|
|
275 end Enclosing_Subprogram_Or_Library_Package;
|
|
276
|
|
277 --------------------------
|
|
278 -- Generate_Dereference --
|
|
279 --------------------------
|
|
280
|
|
281 procedure Generate_Dereference
|
|
282 (N : Node_Id;
|
|
283 Typ : Character := 'r')
|
|
284 is
|
|
285 procedure Create_Heap;
|
|
286 -- Create and decorate the special entity which denotes the heap
|
|
287
|
|
288 -----------------
|
|
289 -- Create_Heap --
|
|
290 -----------------
|
|
291
|
|
292 procedure Create_Heap is
|
|
293 begin
|
|
294 Name_Len := Name_Of_Heap_Variable'Length;
|
|
295 Name_Buffer (1 .. Name_Len) := Name_Of_Heap_Variable;
|
|
296
|
|
297 Heap := Make_Defining_Identifier (Standard_Location, Name_Enter);
|
|
298
|
|
299 Set_Ekind (Heap, E_Variable);
|
|
300 Set_Is_Internal (Heap, True);
|
131
|
301 Set_Scope (Heap, Standard_Standard);
|
111
|
302 Set_Has_Fully_Qualified_Name (Heap);
|
|
303 end Create_Heap;
|
|
304
|
|
305 -- Local variables
|
|
306
|
|
307 Loc : constant Source_Ptr := Sloc (N);
|
|
308
|
|
309 -- Start of processing for Generate_Dereference
|
|
310
|
|
311 begin
|
|
312 if Loc > No_Location then
|
|
313 Drefs.Increment_Last;
|
|
314
|
|
315 declare
|
|
316 Deref_Entry : Xref_Entry renames Drefs.Table (Drefs.Last);
|
|
317 Deref : Xref_Key renames Deref_Entry.Key;
|
|
318
|
|
319 begin
|
|
320 if No (Heap) then
|
|
321 Create_Heap;
|
|
322 end if;
|
|
323
|
|
324 Deref.Ent := Heap;
|
|
325 Deref.Loc := Loc;
|
|
326 Deref.Typ := Typ;
|
|
327
|
|
328 -- It is as if the special "Heap" was defined in the main unit,
|
|
329 -- in the scope of the entity for the main unit. This single
|
|
330 -- definition point is required to ensure that sorting cross
|
|
331 -- references works for "Heap" references as well.
|
|
332
|
|
333 Deref.Eun := Main_Unit;
|
|
334 Deref.Lun := Get_Top_Level_Code_Unit (Loc);
|
|
335
|
|
336 Deref.Ref_Scope := Enclosing_Subprogram_Or_Library_Package (N);
|
|
337 Deref.Ent_Scope := Cunit_Entity (Main_Unit);
|
|
338
|
|
339 Deref_Entry.Def := No_Location;
|
|
340
|
|
341 Deref_Entry.Ent_Scope_File := Main_Unit;
|
|
342 end;
|
|
343 end if;
|
|
344 end Generate_Dereference;
|
|
345
|
|
346 end SPARK_Specific;
|