1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
5 -- S Y S T E M . R I D E N T --
9 -- Copyright (C) 1992-2004 Free Software Foundation, Inc. --
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 2, 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 COPYING. If not, write --
19 -- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, --
20 -- Boston, MA 02110-1301, USA. --
22 -- As a special exception, if other files instantiate generics from this --
23 -- unit, or you link this unit with other files to produce an executable, --
24 -- this unit does not by itself cause the resulting executable to be --
25 -- covered by the GNU General Public License. This exception does not --
26 -- however invalidate any other reasons why the executable file might be --
27 -- covered by the GNU Public License. --
29 -- GNAT was originally developed by the GNAT team at New York University. --
30 -- Extensive contributions were provided by Ada Core Technologies Inc. --
32 ------------------------------------------------------------------------------
34 -- This package defines the set of restriction identifiers. It is a generic
35 -- package that is instantiated by the compiler/binder in package Rident, and
36 -- is instantiated in package System.Restrictions for use at run-time.
38 -- The reason that we make this a generic package is so that in the case of
39 -- the instantiation in Rident for use at compile time and bind time, we can
40 -- generate normal image tables for the enumeration types, which are needed
41 -- for diagnostic and informational messages. At run-time we really do not
42 -- want to waste the space for these image tables, and they are not needed,
43 -- so we can do the instantiation under control of Discard_Names to remove
47 package System
.Rident
is
49 -- The following enumeration type defines the set of restriction
50 -- identifiers that are implemented in GNAT.
52 -- To add a new restriction identifier, add an entry with the name
53 -- to be used in the pragma, and add appropriate calls to the
54 -- Restrict.Check_Restriction routine.
56 type Restriction_Id
is
58 -- The following cases are checked for consistency in the binder
60 (Simple_Barriers
, -- GNAT (Ravenscar)
61 No_Abort_Statements
, -- (RM D.7(5), H.4(3))
62 No_Access_Subprograms
, -- (RM H.4(17))
63 No_Allocators
, -- (RM H.4(7))
64 No_Asynchronous_Control
, -- (RM D.7(10))
66 No_Delay
, -- (RM H.4(21))
67 No_Direct_Boolean_Operators
, -- GNAT
68 No_Dispatch
, -- (RM H.4(19))
69 No_Dynamic_Attachment
, -- GNAT
70 No_Dynamic_Priorities
, -- (RM D.9(9))
71 No_Enumeration_Maps
, -- GNAT
72 No_Entry_Calls_In_Elaboration_Code
, -- GNAT
73 No_Entry_Queue
, -- GNAT (Ravenscar)
74 No_Exception_Handlers
, -- GNAT
75 No_Exception_Registration
, -- GNAT
76 No_Exceptions
, -- (RM H.4(12))
77 No_Finalization
, -- GNAT
78 No_Fixed_Point
, -- (RM H.4(15))
79 No_Floating_Point
, -- (RM H.4(14))
80 No_IO
, -- (RM H.4(20))
81 No_Implicit_Conditionals
, -- GNAT
82 No_Implicit_Dynamic_Code
, -- GNAT
83 No_Implicit_Heap_Allocations
, -- (RM D.8(8), H.4(3))
84 No_Implicit_Loops
, -- GNAT
85 No_Initialize_Scalars
, -- GNAT
86 No_Local_Allocators
, -- (RM H.4(8))
87 No_Local_Protected_Objects
, -- GNAT
88 No_Nested_Finalization
, -- (RM D.7(4))
89 No_Protected_Type_Allocators
, -- GNAT
90 No_Protected_Types
, -- (RM H.4(5))
91 No_Recursion
, -- (RM H.4(22))
92 No_Reentrancy
, -- (RM H.4(23))
93 No_Relative_Delay
, -- GNAT (Ravenscar)
94 No_Requeue_Statements
, -- GNAT
95 No_Secondary_Stack
, -- GNAT
96 No_Select_Statements
, -- GNAT (Ravenscar)
97 No_Standard_Storage_Pools
, -- GNAT
99 No_Task_Allocators
, -- (RM D.7(7))
100 No_Task_Attributes_Package
, -- GNAT
101 No_Task_Hierarchy
, -- (RM D.7(3), H.4(3))
102 No_Task_Termination
, -- GNAT (Ravenscar)
104 No_Terminate_Alternatives
, -- (RM D.7(6))
105 No_Unchecked_Access
, -- (RM H.4(18))
106 No_Unchecked_Conversion
, -- (RM H.4(16))
107 No_Unchecked_Deallocation
, -- (RM H.4(9))
108 No_Wide_Characters
, -- GNAT
109 Static_Priorities
, -- GNAT
110 Static_Storage_Size
, -- GNAT
112 -- The following cases do not require partition-wide checks
114 Immediate_Reclamation
, -- (RM H.4(10))
115 No_Implementation_Attributes
, -- GNAT
116 No_Implementation_Pragmas
, -- GNAT
117 No_Implementation_Restrictions
, -- GNAT
118 No_Elaboration_Code
, -- GNAT
119 No_Obsolescent_Features
, -- Ada 2005 AI-368
121 -- The following cases require a parameter value
123 -- The following entries are fully checked at compile/bind time,
124 -- which means that the compiler can in general tell the minimum
125 -- value which could be used with a restrictions pragma. The binder
126 -- can deduce the appropriate minimum value for the partition by
127 -- taking the maximum value required by any unit.
129 Max_Protected_Entries
, -- (RM D.7(14))
130 Max_Select_Alternatives
, -- (RM D.7(12))
131 Max_Task_Entries
, -- (RM D.7(13), H.4(3))
133 -- The following entries are also fully checked at compile/bind
134 -- time, and the compiler can also at least in some cases tell
135 -- the minimum value which could be used with a restriction pragma.
136 -- The difference is that the contributions are additive, so the
137 -- binder deduces this value by adding the unit contributions.
139 Max_Tasks
, -- (RM D.7(19), H.4(3))
141 -- The following entries are checked at compile time only for
142 -- zero/nonzero entries. This means that the compiler can tell
143 -- at compile time if a restriction value of zero is (would be)
144 -- violated, but that is all. The compiler cannot distinguish
145 -- between different non-zero values.
147 Max_Asynchronous_Select_Nesting
, -- (RM D.7(18), H.4(3))
148 Max_Entry_Queue_Length
, -- GNAT
150 -- The remaining entries are not checked at compile/bind time
152 Max_Storage_At_Blocking
, -- (RM D.7(17))
154 Not_A_Restriction_Id
);
156 -- Synonyms permitted for historical purposes of compatibility.
157 -- Must be coordinated with Restrict.Process_Restriction_Synonym.
159 Boolean_Entry_Barriers
: Restriction_Id
renames Simple_Barriers
;
160 Max_Entry_Queue_Depth
: Restriction_Id
renames Max_Entry_Queue_Length
;
161 No_Dynamic_Interrupts
: Restriction_Id
renames No_Dynamic_Attachment
;
162 No_Requeue
: Restriction_Id
renames No_Requeue_Statements
;
163 No_Task_Attributes
: Restriction_Id
renames No_Task_Attributes_Package
;
165 subtype All_Restrictions
is Restriction_Id
range
166 Simple_Barriers
.. Max_Storage_At_Blocking
;
167 -- All restrictions (excluding only Not_A_Restriction_Id)
169 subtype All_Boolean_Restrictions
is Restriction_Id
range
170 Simple_Barriers
.. No_Obsolescent_Features
;
171 -- All restrictions which do not take a parameter
173 subtype Partition_Boolean_Restrictions
is All_Boolean_Restrictions
range
174 Simple_Barriers
.. Static_Storage_Size
;
175 -- Boolean restrictions that are checked for partition consistency.
176 -- Note that all parameter restrictions are checked for partition
177 -- consistency by default, so this distinction is only needed in the
178 -- case of Boolean restrictions.
180 subtype Cunit_Boolean_Restrictions
is All_Boolean_Restrictions
range
181 Immediate_Reclamation
.. No_Obsolescent_Features
;
182 -- Boolean restrictions that are not checked for partition consistency
183 -- and that thus apply only to the current unit. Note that for these
184 -- restrictions, the compiler does not apply restrictions found in
185 -- with'ed units, parent specs etc to the main unit.
187 subtype All_Parameter_Restrictions
is
189 Max_Protected_Entries
.. Max_Storage_At_Blocking
;
190 -- All restrictions that are take a parameter
192 subtype Checked_Parameter_Restrictions
is
193 All_Parameter_Restrictions
range
194 Max_Protected_Entries
.. Max_Entry_Queue_Length
;
195 -- These are the parameter restrictions that can be at least partially
196 -- checked at compile/binder time. Minimally, the compiler can detect
197 -- violations of a restriction pragma with a value of zero reliably.
199 subtype Checked_Max_Parameter_Restrictions
is
200 Checked_Parameter_Restrictions
range
201 Max_Protected_Entries
.. Max_Task_Entries
;
202 -- Restrictions with parameters that can be checked in some cases by
203 -- maximizing among statically detected instances where the compiler
204 -- can determine the count.
206 subtype Checked_Add_Parameter_Restrictions
is
207 Checked_Parameter_Restrictions
range
208 Max_Tasks
.. Max_Tasks
;
209 -- Restrictions with parameters that can be checked in some cases by
210 -- summing the statically detected instances where the compiler can
211 -- determine the count.
213 subtype Checked_Val_Parameter_Restrictions
is
214 Checked_Parameter_Restrictions
range
215 Max_Protected_Entries
.. Max_Tasks
;
216 -- Restrictions with parameter where the count is known at least in
217 -- some cases by the compiler/binder.
219 subtype Checked_Zero_Parameter_Restrictions
is
220 Checked_Parameter_Restrictions
range
221 Max_Asynchronous_Select_Nesting
.. Max_Entry_Queue_Length
;
222 -- Restrictions with parameters where the compiler can detect the use of
223 -- the feature, and hence violations of a restriction specifying a value
224 -- of zero, but cannot detect specific values other than zero/nonzero.
226 subtype Unchecked_Parameter_Restrictions
is
227 All_Parameter_Restrictions
range
228 Max_Storage_At_Blocking
.. Max_Storage_At_Blocking
;
229 -- Restrictions with parameters where the compiler cannot ever detect
230 -- corresponding compile time usage, so the binder and compiler never
231 -- detect violations of any restriction.
233 -------------------------------------
234 -- Restriction Status Declarations --
235 -------------------------------------
237 -- The following declarations are used to record the current status
238 -- or restrictions (for the current unit, or related units, at compile
239 -- time, and for all units in a partition at bind time or run time).
241 type Restriction_Flags
is array (All_Restrictions
) of Boolean;
242 type Restriction_Values
is array (All_Parameter_Restrictions
) of Natural;
243 type Parameter_Flags
is array (All_Parameter_Restrictions
) of Boolean;
245 type Restrictions_Info
is record
246 Set
: Restriction_Flags
:= (others => False);
247 -- An entry is True in the Set array if a restrictions pragma has
248 -- been encountered for the given restriction. If the value is
249 -- True for a parameter restriction, then the corresponding entry
250 -- in the Value array gives the minimum value encountered for any
253 Value
: Restriction_Values
;
254 -- If the entry for a parameter restriction in Set is True (i.e. a
255 -- restrictions pragma for the restriction has been encountered), then
256 -- the corresponding entry in the Value array is the minimum value
257 -- specified by any such restrictions pragma. Note that a restrictions
258 -- pragma specifying a value greater than Int'Last is simply ignored.
260 Violated
: Restriction_Flags
:= (others => False);
261 -- An entry is True in the violations array if the compiler has
262 -- detected a violation of the restriction. For a parameter
263 -- restriction, the Count and Unknown arrays have additional
266 Count
: Restriction_Values
:= (others => 0);
267 -- If an entry for a parameter restriction is True in Violated,
268 -- the corresponding entry in the Count array may record additional
269 -- information. If the actual minimum count is known (by taking
270 -- maximums, or sums, depending on the restriction), it will be
271 -- recorded in this array. If not, then the value will remain zero.
273 Unknown
: Parameter_Flags
:= (others => False);
274 -- If an entry for a parameter restriction is True in Violated,
275 -- the corresponding entry in the Unknown array may record additional
276 -- information. If the actual count is not known by the compiler (but
277 -- is known to be non-zero), then the entry in Unknown will be True.
278 -- This indicates that the value in Count is not known to be exact,
279 -- and the actual violation count may be higher.
281 -- Note: If Violated (K) is True, then either Count (K) > 0 or
282 -- Unknown (K) = True. It is possible for both these to be set.
283 -- For example, if Count (K) = 3 and Unknown (K) is True, it means
284 -- that the actual violation count is at least 3 but might be higher.
287 ----------------------------------
288 -- Profile Definitions and Data --
289 ----------------------------------
291 type Profile_Name
is (Ravenscar
, Restricted
);
292 -- Names of recognized pfofiles
294 type Profile_Data
is record
295 Set
: Restriction_Flags
;
296 -- Set to True if given restriction must be set for the profile,
297 -- and False if it need not be set (False does not mean that it
298 -- must not be set, just that it need not be set). If the flag
299 -- is True for a parameter restriction, then the Value array
300 -- gives the maximum value permitted by the profile.
302 Value
: Restriction_Values
;
303 -- An entry in this array is meaningful only if the corresponding
304 -- flag in Set is True. In that case, the value in this array is
305 -- the maximum value of the parameter permitted by the profile.
308 Profile_Info
: array (Profile_Name
) of Profile_Data
:=
310 -- Restricted Profile
314 -- Restrictions for Restricted profile
317 (No_Abort_Statements
=> True,
318 No_Asynchronous_Control
=> True,
319 No_Dynamic_Attachment
=> True,
320 No_Dynamic_Priorities
=> True,
321 No_Entry_Queue
=> True,
322 No_Local_Protected_Objects
=> True,
323 No_Protected_Type_Allocators
=> True,
324 No_Requeue_Statements
=> True,
325 No_Task_Allocators
=> True,
326 No_Task_Attributes_Package
=> True,
327 No_Task_Hierarchy
=> True,
328 No_Terminate_Alternatives
=> True,
329 Max_Asynchronous_Select_Nesting
=> True,
330 Max_Protected_Entries
=> True,
331 Max_Select_Alternatives
=> True,
332 Max_Task_Entries
=> True,
335 -- Value settings for Restricted profile
338 (Max_Asynchronous_Select_Nesting
=> 0,
339 Max_Protected_Entries
=> 1,
340 Max_Select_Alternatives
=> 0,
341 Max_Task_Entries
=> 0,
346 -- Note: the table entries here only represent the
347 -- required restriction profile for Ravenscar. The
348 -- full Ravenscar profile also requires:
350 -- pragma Dispatching_Policy (FIFO_Within_Priorities);
351 -- pragma Locking_Policy (Ceiling_Locking);
352 -- pragma Detect_Blocking
356 -- Restrictions for Ravenscar = Restricted profile ..
359 (No_Abort_Statements
=> True,
360 No_Asynchronous_Control
=> True,
361 No_Dynamic_Attachment
=> True,
362 No_Dynamic_Priorities
=> True,
363 No_Entry_Queue
=> True,
364 No_Local_Protected_Objects
=> True,
365 No_Protected_Type_Allocators
=> True,
366 No_Requeue_Statements
=> True,
367 No_Task_Allocators
=> True,
368 No_Task_Attributes_Package
=> True,
369 No_Task_Hierarchy
=> True,
370 No_Terminate_Alternatives
=> True,
371 Max_Asynchronous_Select_Nesting
=> True,
372 Max_Protected_Entries
=> True,
373 Max_Select_Alternatives
=> True,
374 Max_Task_Entries
=> True,
376 -- plus these additional restrictions:
379 No_Implicit_Heap_Allocations
=> True,
380 No_Relative_Delay
=> True,
381 No_Select_Statements
=> True,
382 No_Task_Termination
=> True,
383 Simple_Barriers
=> True,
386 -- Value settings for Ravenscar (same as Restricted)
389 (Max_Asynchronous_Select_Nesting
=> 0,
390 Max_Protected_Entries
=> 1,
391 Max_Select_Alternatives
=> 0,
392 Max_Task_Entries
=> 0,