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------------------------------------------------------------------------------
-- --
-- GNAT COMPILER COMPONENTS --
-- --
-- S Y S T E M . R I D E N T --
-- --
-- S p e c --
-- --
-- Copyright (C) 1992-2005, Free Software Foundation, Inc. --
-- --
-- GNAT is free software; you can redistribute it and/or modify it under --
-- terms of the GNU General Public License as published by the Free Soft- --
-- ware Foundation; either version 2, or (at your option) any later ver- --
-- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
-- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
-- for more details. You should have received a copy of the GNU General --
-- Public License distributed with GNAT; see file COPYING. If not, write --
-- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, --
-- Boston, MA 02110-1301, USA. --
-- --
-- As a special exception, if other files instantiate generics from this --
-- unit, or you link this unit with other files to produce an executable, --
-- this unit does not by itself cause the resulting executable to be --
-- covered by the GNU General Public License. This exception does not --
-- however invalidate any other reasons why the executable file might be --
-- covered by the GNU Public License. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- --
------------------------------------------------------------------------------
-- This package defines the set of restriction identifiers. It is a generic
-- package that is instantiated by the compiler/binder in package Rident, and
-- is instantiated in package System.Restrictions for use at run-time.
-- The reason that we make this a generic package is so that in the case of
-- the instantiation in Rident for use at compile time and bind time, we can
-- generate normal image tables for the enumeration types, which are needed
-- for diagnostic and informational messages. At run-time we really do not
-- want to waste the space for these image tables, and they are not needed,
-- so we can do the instantiation under control of Discard_Names to remove
-- the tables.
generic
package System.Rident is
-- The following enumeration type defines the set of restriction
-- identifiers that are implemented in GNAT.
-- To add a new restriction identifier, add an entry with the name
-- to be used in the pragma, and add appropriate calls to the
-- Restrict.Check_Restriction routine.
type Restriction_Id is
-- The following cases are checked for consistency in the binder
(Simple_Barriers, -- GNAT (Ravenscar)
No_Abort_Statements, -- (RM D.7(5), H.4(3))
No_Access_Subprograms, -- (RM H.4(17))
No_Allocators, -- (RM H.4(7))
No_Asynchronous_Control, -- (RM D.7(10))
No_Calendar, -- GNAT
No_Delay, -- (RM H.4(21))
No_Direct_Boolean_Operators, -- GNAT
No_Dispatch, -- (RM H.4(19))
No_Dispatching_Calls, -- GNAT
No_Dynamic_Attachment, -- GNAT
No_Dynamic_Priorities, -- (RM D.9(9))
No_Enumeration_Maps, -- GNAT
No_Entry_Calls_In_Elaboration_Code, -- GNAT
No_Entry_Queue, -- GNAT (Ravenscar)
No_Exception_Handlers, -- GNAT
No_Exception_Registration, -- GNAT
No_Exceptions, -- (RM H.4(12))
No_Finalization, -- GNAT
No_Fixed_Point, -- (RM H.4(15))
No_Floating_Point, -- (RM H.4(14))
No_IO, -- (RM H.4(20))
No_Implicit_Conditionals, -- GNAT
No_Implicit_Dynamic_Code, -- GNAT
No_Implicit_Heap_Allocations, -- (RM D.8(8), H.4(3))
No_Implicit_Loops, -- GNAT
No_Initialize_Scalars, -- GNAT
No_Local_Allocators, -- (RM H.4(8))
No_Local_Protected_Objects, -- GNAT
No_Nested_Finalization, -- (RM D.7(4))
No_Protected_Type_Allocators, -- GNAT
No_Protected_Types, -- (RM H.4(5))
No_Recursion, -- (RM H.4(22))
No_Reentrancy, -- (RM H.4(23))
No_Relative_Delay, -- GNAT (Ravenscar)
No_Requeue_Statements, -- GNAT
No_Secondary_Stack, -- GNAT
No_Select_Statements, -- GNAT (Ravenscar)
No_Standard_Storage_Pools, -- GNAT
No_Streams, -- GNAT
No_Task_Allocators, -- (RM D.7(7))
No_Task_Attributes_Package, -- GNAT
No_Task_Hierarchy, -- (RM D.7(3), H.4(3))
No_Task_Termination, -- GNAT (Ravenscar)
No_Tasking, -- GNAT
No_Terminate_Alternatives, -- (RM D.7(6))
No_Unchecked_Access, -- (RM H.4(18))
No_Unchecked_Conversion, -- (RM H.4(16))
No_Unchecked_Deallocation, -- (RM H.4(9))
Static_Priorities, -- GNAT
Static_Storage_Size, -- GNAT
-- The following cases do not require partition-wide checks
Immediate_Reclamation, -- (RM H.4(10))
No_Implementation_Attributes, -- Ada 2005 AI-257
No_Implementation_Pragmas, -- Ada 2005 AI-257
No_Implementation_Restrictions, -- GNAT
No_Elaboration_Code, -- GNAT
No_Obsolescent_Features, -- Ada 2005 AI-368
No_Wide_Characters, -- GNAT
-- The following cases require a parameter value
-- The following entries are fully checked at compile/bind time,
-- which means that the compiler can in general tell the minimum
-- value which could be used with a restrictions pragma. The binder
-- can deduce the appropriate minimum value for the partition by
-- taking the maximum value required by any unit.
Max_Protected_Entries, -- (RM D.7(14))
Max_Select_Alternatives, -- (RM D.7(12))
Max_Task_Entries, -- (RM D.7(13), H.4(3))
-- The following entries are also fully checked at compile/bind
-- time, and the compiler can also at least in some cases tell
-- the minimum value which could be used with a restriction pragma.
-- The difference is that the contributions are additive, so the
-- binder deduces this value by adding the unit contributions.
Max_Tasks, -- (RM D.7(19), H.4(3))
-- The following entries are checked at compile time only for
-- zero/nonzero entries. This means that the compiler can tell
-- at compile time if a restriction value of zero is (would be)
-- violated, but that is all. The compiler cannot distinguish
-- between different non-zero values.
Max_Asynchronous_Select_Nesting, -- (RM D.7(18), H.4(3))
Max_Entry_Queue_Length, -- GNAT
-- The remaining entries are not checked at compile/bind time
Max_Storage_At_Blocking, -- (RM D.7(17))
Not_A_Restriction_Id);
-- Synonyms permitted for historical purposes of compatibility.
-- Must be coordinated with Restrict.Process_Restriction_Synonym.
Boolean_Entry_Barriers : Restriction_Id renames Simple_Barriers;
Max_Entry_Queue_Depth : Restriction_Id renames Max_Entry_Queue_Length;
No_Dynamic_Interrupts : Restriction_Id renames No_Dynamic_Attachment;
No_Requeue : Restriction_Id renames No_Requeue_Statements;
No_Task_Attributes : Restriction_Id renames No_Task_Attributes_Package;
subtype All_Restrictions is Restriction_Id range
Simple_Barriers .. Max_Storage_At_Blocking;
-- All restrictions (excluding only Not_A_Restriction_Id)
subtype All_Boolean_Restrictions is Restriction_Id range
Simple_Barriers .. No_Wide_Characters;
-- All restrictions which do not take a parameter
subtype Partition_Boolean_Restrictions is All_Boolean_Restrictions range
Simple_Barriers .. Static_Storage_Size;
-- Boolean restrictions that are checked for partition consistency.
-- Note that all parameter restrictions are checked for partition
-- consistency by default, so this distinction is only needed in the
-- case of Boolean restrictions.
subtype Cunit_Boolean_Restrictions is All_Boolean_Restrictions range
Immediate_Reclamation .. No_Wide_Characters;
-- Boolean restrictions that are not checked for partition consistency
-- and that thus apply only to the current unit. Note that for these
-- restrictions, the compiler does not apply restrictions found in
-- with'ed units, parent specs etc to the main unit.
subtype All_Parameter_Restrictions is
Restriction_Id range
Max_Protected_Entries .. Max_Storage_At_Blocking;
-- All restrictions that are take a parameter
subtype Checked_Parameter_Restrictions is
All_Parameter_Restrictions range
Max_Protected_Entries .. Max_Entry_Queue_Length;
-- These are the parameter restrictions that can be at least partially
-- checked at compile/binder time. Minimally, the compiler can detect
-- violations of a restriction pragma with a value of zero reliably.
subtype Checked_Max_Parameter_Restrictions is
Checked_Parameter_Restrictions range
Max_Protected_Entries .. Max_Task_Entries;
-- Restrictions with parameters that can be checked in some cases by
-- maximizing among statically detected instances where the compiler
-- can determine the count.
subtype Checked_Add_Parameter_Restrictions is
Checked_Parameter_Restrictions range
Max_Tasks .. Max_Tasks;
-- Restrictions with parameters that can be checked in some cases by
-- summing the statically detected instances where the compiler can
-- determine the count.
subtype Checked_Val_Parameter_Restrictions is
Checked_Parameter_Restrictions range
Max_Protected_Entries .. Max_Tasks;
-- Restrictions with parameter where the count is known at least in
-- some cases by the compiler/binder.
subtype Checked_Zero_Parameter_Restrictions is
Checked_Parameter_Restrictions range
Max_Asynchronous_Select_Nesting .. Max_Entry_Queue_Length;
-- Restrictions with parameters where the compiler can detect the use of
-- the feature, and hence violations of a restriction specifying a value
-- of zero, but cannot detect specific values other than zero/nonzero.
subtype Unchecked_Parameter_Restrictions is
All_Parameter_Restrictions range
Max_Storage_At_Blocking .. Max_Storage_At_Blocking;
-- Restrictions with parameters where the compiler cannot ever detect
-- corresponding compile time usage, so the binder and compiler never
-- detect violations of any restriction.
-------------------------------------
-- Restriction Status Declarations --
-------------------------------------
-- The following declarations are used to record the current status
-- or restrictions (for the current unit, or related units, at compile
-- time, and for all units in a partition at bind time or run time).
type Restriction_Flags is array (All_Restrictions) of Boolean;
type Restriction_Values is array (All_Parameter_Restrictions) of Natural;
type Parameter_Flags is array (All_Parameter_Restrictions) of Boolean;
type Restrictions_Info is record
Set : Restriction_Flags := (others => False);
-- An entry is True in the Set array if a restrictions pragma has
-- been encountered for the given restriction. If the value is
-- True for a parameter restriction, then the corresponding entry
-- in the Value array gives the minimum value encountered for any
-- such restriction.
Value : Restriction_Values;
-- If the entry for a parameter restriction in Set is True (i.e. a
-- restrictions pragma for the restriction has been encountered), then
-- the corresponding entry in the Value array is the minimum value
-- specified by any such restrictions pragma. Note that a restrictions
-- pragma specifying a value greater than Int'Last is simply ignored.
Violated : Restriction_Flags := (others => False);
-- An entry is True in the violations array if the compiler has
-- detected a violation of the restriction. For a parameter
-- restriction, the Count and Unknown arrays have additional
-- information.
Count : Restriction_Values := (others => 0);
-- If an entry for a parameter restriction is True in Violated,
-- the corresponding entry in the Count array may record additional
-- information. If the actual minimum count is known (by taking
-- maximums, or sums, depending on the restriction), it will be
-- recorded in this array. If not, then the value will remain zero.
Unknown : Parameter_Flags := (others => False);
-- If an entry for a parameter restriction is True in Violated,
-- the corresponding entry in the Unknown array may record additional
-- information. If the actual count is not known by the compiler (but
-- is known to be non-zero), then the entry in Unknown will be True.
-- This indicates that the value in Count is not known to be exact,
-- and the actual violation count may be higher.
-- Note: If Violated (K) is True, then either Count (K) > 0 or
-- Unknown (K) = True. It is possible for both these to be set.
-- For example, if Count (K) = 3 and Unknown (K) is True, it means
-- that the actual violation count is at least 3 but might be higher.
end record;
----------------------------------
-- Profile Definitions and Data --
----------------------------------
type Profile_Name is (Ravenscar, Restricted);
-- Names of recognized pfofiles
type Profile_Data is record
Set : Restriction_Flags;
-- Set to True if given restriction must be set for the profile,
-- and False if it need not be set (False does not mean that it
-- must not be set, just that it need not be set). If the flag
-- is True for a parameter restriction, then the Value array
-- gives the maximum value permitted by the profile.
Value : Restriction_Values;
-- An entry in this array is meaningful only if the corresponding
-- flag in Set is True. In that case, the value in this array is
-- the maximum value of the parameter permitted by the profile.
end record;
Profile_Info : array (Profile_Name) of Profile_Data :=
-- Restricted Profile
(Restricted =>
-- Restrictions for Restricted profile
(Set =>
(No_Abort_Statements => True,
No_Asynchronous_Control => True,
No_Dynamic_Attachment => True,
No_Dynamic_Priorities => True,
No_Entry_Queue => True,
No_Local_Protected_Objects => True,
No_Protected_Type_Allocators => True,
No_Requeue_Statements => True,
No_Task_Allocators => True,
No_Task_Attributes_Package => True,
No_Task_Hierarchy => True,
No_Terminate_Alternatives => True,
Max_Asynchronous_Select_Nesting => True,
Max_Protected_Entries => True,
Max_Select_Alternatives => True,
Max_Task_Entries => True,
others => False),
-- Value settings for Restricted profile
Value =>
(Max_Asynchronous_Select_Nesting => 0,
Max_Protected_Entries => 1,
Max_Select_Alternatives => 0,
Max_Task_Entries => 0,
others => 0)),
-- Ravenscar Profile
-- Note: the table entries here only represent the
-- required restriction profile for Ravenscar. The
-- full Ravenscar profile also requires:
-- pragma Dispatching_Policy (FIFO_Within_Priorities);
-- pragma Locking_Policy (Ceiling_Locking);
-- pragma Detect_Blocking
Ravenscar =>
-- Restrictions for Ravenscar = Restricted profile ..
(Set =>
(No_Abort_Statements => True,
No_Asynchronous_Control => True,
No_Dynamic_Attachment => True,
No_Dynamic_Priorities => True,
No_Entry_Queue => True,
No_Local_Protected_Objects => True,
No_Protected_Type_Allocators => True,
No_Requeue_Statements => True,
No_Task_Allocators => True,
No_Task_Attributes_Package => True,
No_Task_Hierarchy => True,
No_Terminate_Alternatives => True,
Max_Asynchronous_Select_Nesting => True,
Max_Protected_Entries => True,
Max_Select_Alternatives => True,
Max_Task_Entries => True,
-- plus these additional restrictions:
No_Calendar => True,
No_Implicit_Heap_Allocations => True,
No_Relative_Delay => True,
No_Select_Statements => True,
No_Task_Termination => True,
Simple_Barriers => True,
others => False),
-- Value settings for Ravenscar (same as Restricted)
Value =>
(Max_Asynchronous_Select_Nesting => 0,
Max_Protected_Entries => 1,
Max_Select_Alternatives => 0,
Max_Task_Entries => 0,
others => 0)));
end System.Rident;