URL
https://opencores.org/ocsvn/openrisc_me/openrisc_me/trunk
Subversion Repositories openrisc_me
[/] [openrisc/] [trunk/] [gnu-src/] [gcc-4.5.1/] [gcc/] [ada/] [s-parame.ads] - Rev 281
Compare with Previous | Blame | View Log
------------------------------------------------------------------------------ -- -- -- GNAT COMPILER COMPONENTS -- -- -- -- S Y S T E M . P A R A M E T E R S -- -- -- -- S p e c -- -- -- -- Copyright (C) 1992-2009, 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 3, 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. -- -- -- -- As a special exception under Section 7 of GPL version 3, you are granted -- -- additional permissions described in the GCC Runtime Library Exception, -- -- version 3.1, as published by the Free Software Foundation. -- -- -- -- You should have received a copy of the GNU General Public License and -- -- a copy of the GCC Runtime Library Exception along with this program; -- -- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -- -- <http://www.gnu.org/licenses/>. -- -- -- -- GNAT was originally developed by the GNAT team at New York University. -- -- Extensive contributions were provided by Ada Core Technologies Inc. -- -- -- ------------------------------------------------------------------------------ -- Default version used when no target-specific version 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. pragma Compiler_Unit; package System.Parameters is pragma Pure; --------------------------------------- -- 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 Default_Env_Stack_Size : constant Size_Type := 8_192_000; -- Assumed size of the environment task, if no other information -- is available. This value is used when stack checking is -- enabled and no GNAT_STACK_LIMIT environment variable is set. 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 omitted only for outer level objects 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) --------------------- -- Tasking Profile -- --------------------- -- In the following sections, constant parameters are defined to -- allow some optimizations and fine tuning within the tasking run time -- based on restrictions on the tasking features. ---------------------- -- Locking Strategy -- ---------------------- Single_Lock : constant Boolean := False; -- Indicates whether a single lock should be used within the tasking -- run-time to protect internal structures. If True, a single lock -- will be used, meaning less locking/unlocking operations, but also -- more global contention. In general, Single_Lock should be set to -- True on single processor machines, and to False to multi-processor -- systems, but this can vary from application to application and also -- depends on the scheduling policy. ------------------- -- Task Abortion -- ------------------- No_Abort : constant Boolean := False; -- This constant indicates whether abort statements and asynchronous -- transfer of control (ATC) are disallowed. If set to True, it is -- assumed that neither construct is used, and the run time does not -- need to defer/undefer abort and check for pending actions at -- completion points. A value of True for No_Abort corresponds to: -- pragma Restrictions (No_Abort_Statements); -- pragma Restrictions (Max_Asynchronous_Select_Nesting => 0); --------------------- -- Task Attributes -- --------------------- Default_Attribute_Count : constant := 4; -- Number of pre-allocated Address-sized task attributes stored in the -- task control block. -------------------- -- Runtime Traces -- -------------------- Runtime_Traces : constant Boolean := False; -- This constant indicates whether the runtime outputs traces to a -- predefined output or not (True means that traces are output). -- See System.Traces for more details. ----------------------- -- Task Image Length -- ----------------------- Max_Task_Image_Length : constant := 256; -- This constant specifies the maximum length of a task's image ------------------------------ -- Exception Message Length -- ------------------------------ Default_Exception_Msg_Max_Length : constant := 200; -- This constant specifies the default number of characters to allow -- in an exception message (200 is minimum required by RM 11.4.1(18)). end System.Parameters;