------------------------------------------------------------------------------ -- -- -- GNAT RUN-TIME COMPONENTS -- -- -- -- S Y S T E M -- -- -- -- S p e c -- -- (OpenVMS 64bit Itanium GCC_ZCX DEC Threads Version) -- -- -- -- Copyright (C) 1992-2011, 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 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 -- -- . -- -- -- -- 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; -- 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 := 2 ** Integer'Size - 1; 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. 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; pragma Warnings (Off, Default_Bit_Order); -- kill constant condition warning -- 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. Backend_Divide_Checks : constant Boolean := False; Backend_Overflow_Checks : constant Boolean := True; Command_Line_Args : constant Boolean := True; Configurable_Run_Time : constant Boolean := False; Denorm : constant Boolean := True; Duration_32_Bits : constant Boolean := False; Exit_Status_Supported : constant Boolean := True; Fractional_Fixed_Ops : constant Boolean := False; Frontend_Layout : 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; Stack_Check_Limits : constant Boolean := False; Support_Aggregates : constant Boolean := True; Support_Composite_Assign : constant Boolean := True; Support_Composite_Compare : constant Boolean := True; Support_Long_Shifts : constant Boolean := True; Always_Compatible_Rep : constant Boolean := True; Suppress_Standard_Library : constant Boolean := False; Use_Ada_Main_Program_Name : constant Boolean := False; ZCX_By_Default : constant Boolean := True; -------------------------- -- 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 -- then force rebuilding your application if you need different options: -- $ gnatmake -f 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 (Cond_Value : Integer); pragma Interface (C, Lib_Stop); pragma Import_Procedure (Lib_Stop, "LIB$STOP", Mechanism => (Value)); -- Interface to VMS condition handling. Used by RTSfind and pragma -- {Import,Export}_Exception. Put here because this is the only -- VMS specific package that doesn't drag in tasking. ADA_GNAT : constant Boolean := True; pragma Export_Object (ADA_GNAT, "ADA$GNAT"); -- Ubiquitous global symbol identifying a GNAT compiled image to VMS Debug. -- Do not remove! pragma Ident ("GNAT"); -- Gnat_Static_Version_String -- Default ident for all VMS images. end System;