1 ------------------------------------------------------------------------------
3 -- GNAT RUN-TIME COMPONENTS --
8 -- (OpenVMS 64bit GCC_ZCX DEC Threads Version) --
10 -- Copyright (C) 2004 Free Software Foundation, Inc. --
12 -- This specification is derived from the Ada Reference Manual for use with --
13 -- GNAT. The copyright notice above, and the license provisions that follow --
14 -- apply solely to the contents of the part following the private keyword. --
16 -- GNAT is free software; you can redistribute it and/or modify it under --
17 -- terms of the GNU General Public License as published by the Free Soft- --
18 -- ware Foundation; either version 2, or (at your option) any later ver- --
19 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
20 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
21 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
22 -- for more details. You should have received a copy of the GNU General --
23 -- Public License distributed with GNAT; see file COPYING. If not, write --
24 -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
25 -- MA 02111-1307, USA. --
27 -- As a special exception, if other files instantiate generics from this --
28 -- unit, or you link this unit with other files to produce an executable, --
29 -- this unit does not by itself cause the resulting executable to be --
30 -- covered by the GNU General Public License. This exception does not --
31 -- however invalidate any other reasons why the executable file might be --
32 -- covered by the GNU Public License. --
34 -- GNAT was originally developed by the GNAT team at New York University. --
35 -- Extensive contributions were provided by Ada Core Technologies Inc. --
37 ------------------------------------------------------------------------------
41 -- Note that we take advantage of the implementation permission to
42 -- make this unit Pure instead of Preelaborable, see RM 13.7(36)
44 type Name is (SYSTEM_NAME_GNAT);
45 System_Name : constant Name := SYSTEM_NAME_GNAT;
47 -- System-Dependent Named Numbers
49 Min_Int : constant := Long_Long_Integer'First;
50 Max_Int : constant := Long_Long_Integer'Last;
52 Max_Binary_Modulus : constant := 2 ** Long_Long_Integer'Size;
53 Max_Nonbinary_Modulus : constant := Integer'Last;
55 Max_Base_Digits : constant := Long_Long_Float'Digits;
56 Max_Digits : constant := Long_Long_Float'Digits;
58 Max_Mantissa : constant := 63;
59 Fine_Delta : constant := 2.0 ** (-Max_Mantissa);
61 Tick : constant := 0.01;
63 -- Storage-related Declarations
65 type Address is new Long_Integer;
66 Null_Address : constant Address;
68 Storage_Unit : constant := 8;
69 Word_Size : constant := 64;
70 Memory_Size : constant := 2 ** 64;
74 function "<" (Left, Right : Address) return Boolean;
75 function "<=" (Left, Right : Address) return Boolean;
76 function ">" (Left, Right : Address) return Boolean;
77 function ">=" (Left, Right : Address) return Boolean;
78 function "=" (Left, Right : Address) return Boolean;
80 pragma Import (Intrinsic, "<");
81 pragma Import (Intrinsic, "<=");
82 pragma Import (Intrinsic, ">");
83 pragma Import (Intrinsic, ">=");
84 pragma Import (Intrinsic, "=");
86 -- Abstract declarations for arithmetic operations on type address.
87 -- These declarations are needed when Address is non-private. They
88 -- avoid excessive visibility of arithmetic operations on address
89 -- which are typically available elsewhere (e.g. Storage_Elements)
90 -- and which would cause excessive ambiguities in application code.
92 function "+" (Left, Right : Address) return Address is abstract;
93 function "-" (Left, Right : Address) return Address is abstract;
94 function "/" (Left, Right : Address) return Address is abstract;
95 function "*" (Left, Right : Address) return Address is abstract;
96 function "mod" (Left, Right : Address) return Address is abstract;
98 -- Other System-Dependent Declarations
100 type Bit_Order is (High_Order_First, Low_Order_First);
101 Default_Bit_Order : constant Bit_Order := Low_Order_First;
103 -- Priority-related Declarations (RM D.1)
105 Max_Priority : constant Positive := 30;
106 Max_Interrupt_Priority : constant Positive := 31;
108 subtype Any_Priority is Integer range 0 .. 31;
109 subtype Priority is Any_Priority range 0 .. 30;
110 subtype Interrupt_Priority is Any_Priority range 31 .. 31;
112 Default_Priority : constant Priority := 15;
116 Null_Address : constant Address := 0;
118 --------------------------------------
119 -- System Implementation Parameters --
120 --------------------------------------
122 -- These parameters provide information about the target that is used
123 -- by the compiler. They are in the private part of System, where they
124 -- can be accessed using the special circuitry in the Targparm unit
125 -- whose source should be consulted for more detailed descriptions
126 -- of the individual switch values.
128 AAMP : constant Boolean := False;
129 Backend_Divide_Checks : constant Boolean := False;
130 Backend_Overflow_Checks : constant Boolean := False;
131 Command_Line_Args : constant Boolean := True;
132 Configurable_Run_Time : constant Boolean := False;
133 Denorm : constant Boolean := False;
134 Duration_32_Bits : constant Boolean := False;
135 Exit_Status_Supported : constant Boolean := True;
136 Fractional_Fixed_Ops : constant Boolean := False;
137 Frontend_Layout : constant Boolean := False;
138 Functions_Return_By_DSP : constant Boolean := False;
139 Machine_Overflows : constant Boolean := False;
140 Machine_Rounds : constant Boolean := True;
141 OpenVMS : constant Boolean := True;
142 Signed_Zeros : constant Boolean := True;
143 Stack_Check_Default : constant Boolean := True;
144 Stack_Check_Probes : constant Boolean := True;
145 Support_64_Bit_Divides : constant Boolean := True;
146 Support_Aggregates : constant Boolean := True;
147 Support_Composite_Assign : constant Boolean := True;
148 Support_Composite_Compare : constant Boolean := True;
149 Support_Long_Shifts : constant Boolean := True;
150 Suppress_Standard_Library : constant Boolean := False;
151 Use_Ada_Main_Program_Name : constant Boolean := False;
152 ZCX_By_Default : constant Boolean := True;
153 GCC_ZCX_Support : constant Boolean := True;
154 Front_End_ZCX_Support : constant Boolean := False;
156 -- Obsolete entries, to be removed eventually (bootstrap issues!)
158 High_Integrity_Mode : constant Boolean := False;
159 Long_Shifts_Inlined : constant Boolean := False;
161 --------------------------
162 -- Underlying Priorities --
163 ---------------------------
165 -- Important note: this section of the file must come AFTER the
166 -- definition of the system implementation parameters to ensure
167 -- that the value of these parameters is available for analysis
168 -- of the declarations here (using Rtsfind at compile time).
170 -- The underlying priorities table provides a generalized mechanism
171 -- for mapping from Ada priorities to system priorities. In some
172 -- cases a 1-1 mapping is not the convenient or optimal choice.
174 -- For DEC Threads OpenVMS, we use the full range of 31 priorities
175 -- in the Ada model, but map them by compression onto the more limited
176 -- range of priorities available in OpenVMS.
178 -- To replace the default values of the Underlying_Priorities mapping,
179 -- copy this source file into your build directory, edit the file to
180 -- reflect your desired behavior, and recompile with the command:
182 -- $ gcc -c -O3 -gnatpgn system.ads
184 -- then recompile the run-time parts that depend on this package:
186 -- $ gnatmake -a -gnatn -O3 <your application>
188 -- then force rebuilding your application if you need different options:
190 -- $ gnatmake -f <your options> <your application>
192 type Priorities_Mapping is array (Any_Priority) of Integer;
193 pragma Suppress_Initialization (Priorities_Mapping);
194 -- Suppress initialization in case gnat.adc specifies Normalize_Scalars
196 Underlying_Priorities : constant Priorities_Mapping :=
198 (Priority'First => 16,
215 Default_Priority => 24,
234 Interrupt_Priority => 31);
236 ----------------------------
237 -- Special VMS Interfaces --
238 ----------------------------
240 procedure Lib_Stop (I : in Integer);
241 pragma Interface (C, Lib_Stop);
242 pragma Import_Procedure (Lib_Stop, "LIB$STOP", Mechanism => (Value));
243 -- Interface to VMS condition handling. Used by RTSfind and pragma
244 -- {Import,Export}_Exception. Put here because this is the only
245 -- VMS specific package that doesn't drag in tasking.