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------------------------------------------------------------------------------
-- --
-- GNAT RUN-TIME COMPONENTS --
-- --
-- S Y S T E M --
-- --
-- S p e c --
-- (OpenVMS 64bit GCC_ZCX DEC Threads Version) --
-- --
-- Copyright (C) 2005 Free Software Foundation, Inc. --
-- --
-- This specification is derived from the Ada Reference Manual for use with --
-- GNAT. The copyright notice above, and the license provisions that follow --
-- apply solely to the contents of the part following the private keyword. --
-- --
-- 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. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- --
------------------------------------------------------------------------------
package System is
pragma Pure (System);
-- Note that we take advantage of the implementation permission to make this
-- unit Pure instead of Preelaborable; see RM 13.7.1(15). In Ada 2005, this is
-- Pure in any case (AI-362).
type Name is (SYSTEM_NAME_GNAT);
System_Name : constant Name := SYSTEM_NAME_GNAT;
-- System-Dependent Named Numbers
Min_Int : constant := Long_Long_Integer'First;
Max_Int : constant := Long_Long_Integer'Last;
Max_Binary_Modulus : constant := 2 ** Long_Long_Integer'Size;
Max_Nonbinary_Modulus : constant := Integer'Last;
Max_Base_Digits : constant := Long_Long_Float'Digits;
Max_Digits : constant := Long_Long_Float'Digits;
Max_Mantissa : constant := 63;
Fine_Delta : constant := 2.0 ** (-Max_Mantissa);
Tick : constant := 0.01;
-- Storage-related Declarations
type Address is new Long_Integer;
Null_Address : constant Address;
-- Although this is declared as an integer type, no arithmetic operations
-- are available (see abstract declarations below), and furthermore there
-- is special processing in the compiler that prevents the use of integer
-- literals with this type (use To_Address to convert integer literals).
--
-- Conversion to and from Short_Address is however freely permitted, and
-- is indeed the reason that Address is declared as an integer type. See
--
Storage_Unit : constant := 8;
Word_Size : constant := 64;
Memory_Size : constant := 2 ** 64;
-- Address comparison
function "<" (Left, Right : Address) return Boolean;
function "<=" (Left, Right : Address) return Boolean;
function ">" (Left, Right : Address) return Boolean;
function ">=" (Left, Right : Address) return Boolean;
function "=" (Left, Right : Address) return Boolean;
pragma Import (Intrinsic, "<");
pragma Import (Intrinsic, "<=");
pragma Import (Intrinsic, ">");
pragma Import (Intrinsic, ">=");
pragma Import (Intrinsic, "=");
-- Abstract declarations for arithmetic operations on type address.
-- These declarations are needed when Address is non-private. They
-- avoid excessive visibility of arithmetic operations on address
-- which are typically available elsewhere (e.g. Storage_Elements)
-- and which would cause excessive ambiguities in application code.
function "+" (Left, Right : Address) return Address is abstract;
function "-" (Left, Right : Address) return Address is abstract;
function "/" (Left, Right : Address) return Address is abstract;
function "*" (Left, Right : Address) return Address is abstract;
function "mod" (Left, Right : Address) return Address is abstract;
-- Other System-Dependent Declarations
type Bit_Order is (High_Order_First, Low_Order_First);
Default_Bit_Order : constant Bit_Order := Low_Order_First;
-- Priority-related Declarations (RM D.1)
Max_Priority : constant Positive := 30;
Max_Interrupt_Priority : constant Positive := 31;
subtype Any_Priority is Integer range 0 .. 31;
subtype Priority is Any_Priority range 0 .. 30;
subtype Interrupt_Priority is Any_Priority range 31 .. 31;
Default_Priority : constant Priority := 15;
private
Null_Address : constant Address := 0;
--------------------------------------
-- System Implementation Parameters --
--------------------------------------
-- These parameters provide information about the target that is used
-- by the compiler. They are in the private part of System, where they
-- can be accessed using the special circuitry in the Targparm unit
-- whose source should be consulted for more detailed descriptions
-- of the individual switch values.
AAMP : constant Boolean := False;
Backend_Divide_Checks : constant Boolean := False;
Backend_Overflow_Checks : constant Boolean := False;
Command_Line_Args : constant Boolean := True;
Compiler_System_Version : constant Boolean := False;
Configurable_Run_Time : constant Boolean := False;
Denorm : constant Boolean := False;
Duration_32_Bits : constant Boolean := False;
Exit_Status_Supported : constant Boolean := True;
Fractional_Fixed_Ops : constant Boolean := False;
Frontend_Layout : constant Boolean := False;
Functions_Return_By_DSP : constant Boolean := False;
Machine_Overflows : constant Boolean := False;
Machine_Rounds : constant Boolean := True;
OpenVMS : constant Boolean := True;
Preallocated_Stacks : constant Boolean := False;
Signed_Zeros : constant Boolean := True;
Stack_Check_Default : constant Boolean := True;
Stack_Check_Probes : constant Boolean := True;
Support_64_Bit_Divides : constant Boolean := True;
Support_Aggregates : constant Boolean := True;
Support_Composite_Assign : constant Boolean := True;
Support_Composite_Compare : constant Boolean := True;
Support_Long_Shifts : constant Boolean := True;
Suppress_Standard_Library : constant Boolean := False;
Use_Ada_Main_Program_Name : constant Boolean := False;
ZCX_By_Default : constant Boolean := True;
GCC_ZCX_Support : constant Boolean := True;
Front_End_ZCX_Support : constant Boolean := False;
-- Obsolete entries, to be removed eventually (bootstrap issues!)
High_Integrity_Mode : constant Boolean := False;
Long_Shifts_Inlined : constant Boolean := False;
--------------------------
-- Underlying Priorities --
---------------------------
-- Important note: this section of the file must come AFTER the
-- definition of the system implementation parameters to ensure
-- that the value of these parameters is available for analysis
-- of the declarations here (using Rtsfind at compile time).
-- The underlying priorities table provides a generalized mechanism
-- for mapping from Ada priorities to system priorities. In some
-- cases a 1-1 mapping is not the convenient or optimal choice.
-- For DEC Threads OpenVMS, we use the full range of 31 priorities
-- in the Ada model, but map them by compression onto the more limited
-- range of priorities available in OpenVMS.
-- To replace the default values of the Underlying_Priorities mapping,
-- copy this source file into your build directory, edit the file to
-- reflect your desired behavior, and recompile with the command:
-- $ gcc -c -O3 -gnatpgn system.ads
-- then recompile the run-time parts that depend on this package:
-- $ gnatmake -a -gnatn -O3 <your application>
-- then force rebuilding your application if you need different options:
-- $ gnatmake -f <your options> <your application>
type Priorities_Mapping is array (Any_Priority) of Integer;
pragma Suppress_Initialization (Priorities_Mapping);
-- Suppress initialization in case gnat.adc specifies Normalize_Scalars
Underlying_Priorities : constant Priorities_Mapping :=
(Priority'First => 16,
1 => 17,
2 => 18,
3 => 18,
4 => 18,
5 => 18,
6 => 19,
7 => 19,
8 => 19,
9 => 20,
10 => 20,
11 => 21,
12 => 21,
13 => 22,
14 => 23,
Default_Priority => 24,
16 => 25,
17 => 25,
18 => 25,
19 => 26,
20 => 26,
21 => 26,
22 => 27,
23 => 27,
24 => 27,
25 => 28,
26 => 28,
27 => 29,
28 => 29,
29 => 30,
Priority'Last => 30,
Interrupt_Priority => 31);
----------------------------
-- Special VMS Interfaces --
----------------------------
procedure Lib_Stop (I : in Integer);
pragma Interface (C, Lib_Stop);
pragma Import_Procedure (Lib_Stop, "LIB$STOP", Mechanism => (Value));
-- Interface to VMS condition handling. Used by RTSfind and pragma
-- {Import,Export}_Exception. Put here because this is the only
-- VMS specific package that doesn't drag in tasking.
end System;
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