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diff --git a/gcc/ada/s-parame.ads b/gcc/ada/s-parame.ads new file mode 100644 index 00000000000..92028c17398 --- /dev/null +++ b/gcc/ada/s-parame.ads @@ -0,0 +1,136 @@ +------------------------------------------------------------------------------ +-- -- +-- GNAT COMPILER COMPONENTS -- +-- -- +-- S Y S T E M . P A R A M E T E R S -- +-- -- +-- S p e c -- +-- -- +-- $Revision: 1.41 $ +-- -- +-- Copyright (C) 1992-2000 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, 59 Temple Place - Suite 330, Boston, -- +-- MA 02111-1307, 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. -- +-- It is now maintained by Ada Core Technologies Inc (http://www.gnat.com). -- +-- -- +------------------------------------------------------------------------------ + +-- This is the default version used for all systems for which no special +-- target-specific version of this package is provided. + +-- This package defines some system dependent parameters for GNAT. These +-- are values that are referenced by the runtime library and are therefore +-- relevant to the target machine. + +-- The parameters whose value is defined in the spec are not generally +-- expected to be changed. If they are changed, it will be necessary to +-- recompile the run-time library. + +-- The parameters which are defined by functions can be changed by modifying +-- the body of System.Parameters in file s-parame.adb. A change to this body +-- requires only rebinding and relinking of the application. + +-- Note: do not introduce any pragma Inline statements into this unit, since +-- otherwise the relinking and rebinding capability would be deactivated. + +package System.Parameters is +pragma Pure (Parameters); + + --------------------------------------- + -- Task And Stack Allocation Control -- + --------------------------------------- + + type Task_Storage_Size is new Integer; + -- Type used in tasking units for task storage size + + type Size_Type is new Task_Storage_Size; + -- Type used to provide task storage size to runtime + + Unspecified_Size : constant Size_Type := Size_Type'First; + -- Value used to indicate that no size type is set + + subtype Ratio is Size_Type range -1 .. 100; + Dynamic : constant Size_Type := -1; + -- The secondary stack ratio is a constant between 0 and 100 which + -- determines the percentage of the allocated task stack that is + -- used by the secondary stack (the rest being the primary stack). + -- The special value of minus one indicates that the secondary + -- stack is to be allocated from the heap instead. + + Sec_Stack_Ratio : constant Ratio := Dynamic; + -- This constant defines the handling of the secondary stack + + Sec_Stack_Dynamic : constant Boolean := Sec_Stack_Ratio = Dynamic; + -- Convenient Boolean for testing for dynamic secondary stack + + function Default_Stack_Size return Size_Type; + -- Default task stack size used if none is specified + + function Minimum_Stack_Size return Size_Type; + -- Minimum task stack size permitted + + function Adjust_Storage_Size (Size : Size_Type) return Size_Type; + -- Given the storage size stored in the TCB, return the Storage_Size + -- value required by the RM for the Storage_Size attribute. The + -- required adjustment is as follows: + -- + -- when Size = Unspecified_Size, return Default_Stack_Size + -- when Size < Minimum_Stack_Size, return Minimum_Stack_Size + -- otherwise return given Size + + Stack_Grows_Down : constant Boolean := True; + -- This constant indicates whether the stack grows up (False) or + -- down (True) in memory as functions are called. It is used for + -- proper implementation of the stack overflow check. + + ---------------------------------------------- + -- Characteristics of types in Interfaces.C -- + ---------------------------------------------- + + long_bits : constant := Long_Integer'Size; + -- Number of bits in type long and unsigned_long. The normal convention + -- is that this is the same as type Long_Integer, but this is not true + -- of all targets. For example, in OpenVMS long /= Long_Integer. + + ---------------------------------------------- + -- Behavior of Pragma Finalize_Storage_Only -- + ---------------------------------------------- + + -- Garbage_Collected is a Boolean constant whose value indicates the + -- effect of the pragma Finalize_Storage_Entry on a controlled type. + + -- Garbage_Collected = False + + -- The system releases all storage on program termination only, + -- but not other garbage collection occurs, so finalization calls + -- are ommitted only for outer level onjects can be omitted if + -- pragma Finalize_Storage_Only is used. + + -- Garbage_Collected = True + + -- The system provides full garbage collection, so it is never + -- necessary to release storage for controlled objects for which + -- a pragma Finalize_Storage_Only is used. + + Garbage_Collected : constant Boolean := False; + -- The storage mode for this system (release on program exit) + +end System.Parameters; |
