1 ------------------------------------------------------------------------------
3 -- GNAT RUN-TIME COMPONENTS --
8 -- (OpenVMS 64bit GCC_ZCX DEC Threads Version) --
10 -- Copyright (C) 2005 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;
67 -- Although this is declared as an integer type, no arithmetic operations
68 -- are available (see abstract declarations below), and furthermore there
69 -- is special processing in the compiler that prevents the use of integer
70 -- literals with this type (use To_Address to convert integer literals).
72 -- Conversion to and from Short_Address is however freely permitted, and
73 -- is indeed the reason that Address is declared as an integer type. See
76 Storage_Unit : constant := 8;
77 Word_Size : constant := 64;
78 Memory_Size : constant := 2 ** 64;
82 function "<" (Left, Right : Address) return Boolean;
83 function "<=" (Left, Right : Address) return Boolean;
84 function ">" (Left, Right : Address) return Boolean;
85 function ">=" (Left, Right : Address) return Boolean;
86 function "=" (Left, Right : Address) return Boolean;
88 pragma Import (Intrinsic, "<");
89 pragma Import (Intrinsic, "<=");
90 pragma Import (Intrinsic, ">");
91 pragma Import (Intrinsic, ">=");
92 pragma Import (Intrinsic, "=");
94 -- Abstract declarations for arithmetic operations on type address.
95 -- These declarations are needed when Address is non-private. They
96 -- avoid excessive visibility of arithmetic operations on address
97 -- which are typically available elsewhere (e.g. Storage_Elements)
98 -- and which would cause excessive ambiguities in application code.
100 function "+" (Left, Right : Address) return Address is abstract;
101 function "-" (Left, Right : Address) return Address is abstract;
102 function "/" (Left, Right : Address) return Address is abstract;
103 function "*" (Left, Right : Address) return Address is abstract;
104 function "mod" (Left, Right : Address) return Address is abstract;
106 -- Other System-Dependent Declarations
108 type Bit_Order is (High_Order_First, Low_Order_First);
109 Default_Bit_Order : constant Bit_Order := Low_Order_First;
111 -- Priority-related Declarations (RM D.1)
113 Max_Priority : constant Positive := 30;
114 Max_Interrupt_Priority : constant Positive := 31;
116 subtype Any_Priority is Integer range 0 .. 31;
117 subtype Priority is Any_Priority range 0 .. 30;
118 subtype Interrupt_Priority is Any_Priority range 31 .. 31;
120 Default_Priority : constant Priority := 15;
124 Null_Address : constant Address := 0;
126 --------------------------------------
127 -- System Implementation Parameters --
128 --------------------------------------
130 -- These parameters provide information about the target that is used
131 -- by the compiler. They are in the private part of System, where they
132 -- can be accessed using the special circuitry in the Targparm unit
133 -- whose source should be consulted for more detailed descriptions
134 -- of the individual switch values.
136 AAMP : constant Boolean := False;
137 Backend_Divide_Checks : constant Boolean := False;
138 Backend_Overflow_Checks : constant Boolean := False;
139 Command_Line_Args : constant Boolean := True;
140 Compiler_System_Version : constant Boolean := False;
141 Configurable_Run_Time : constant Boolean := False;
142 Denorm : constant Boolean := False;
143 Duration_32_Bits : constant Boolean := False;
144 Exit_Status_Supported : constant Boolean := True;
145 Fractional_Fixed_Ops : constant Boolean := False;
146 Frontend_Layout : constant Boolean := False;
147 Functions_Return_By_DSP : constant Boolean := False;
148 Machine_Overflows : constant Boolean := False;
149 Machine_Rounds : constant Boolean := True;
150 OpenVMS : constant Boolean := True;
151 Preallocated_Stacks : constant Boolean := False;
152 Signed_Zeros : constant Boolean := True;
153 Stack_Check_Default : constant Boolean := True;
154 Stack_Check_Probes : constant Boolean := True;
155 Support_64_Bit_Divides : constant Boolean := True;
156 Support_Aggregates : constant Boolean := True;
157 Support_Composite_Assign : constant Boolean := True;
158 Support_Composite_Compare : constant Boolean := True;
159 Support_Long_Shifts : constant Boolean := True;
160 Suppress_Standard_Library : constant Boolean := False;
161 Use_Ada_Main_Program_Name : constant Boolean := False;
162 ZCX_By_Default : constant Boolean := True;
163 GCC_ZCX_Support : constant Boolean := True;
164 Front_End_ZCX_Support : constant Boolean := False;
166 -- Obsolete entries, to be removed eventually (bootstrap issues!)
168 High_Integrity_Mode : constant Boolean := False;
169 Long_Shifts_Inlined : constant Boolean := False;
171 --------------------------
172 -- Underlying Priorities --
173 ---------------------------
175 -- Important note: this section of the file must come AFTER the
176 -- definition of the system implementation parameters to ensure
177 -- that the value of these parameters is available for analysis
178 -- of the declarations here (using Rtsfind at compile time).
180 -- The underlying priorities table provides a generalized mechanism
181 -- for mapping from Ada priorities to system priorities. In some
182 -- cases a 1-1 mapping is not the convenient or optimal choice.
184 -- For DEC Threads OpenVMS, we use the full range of 31 priorities
185 -- in the Ada model, but map them by compression onto the more limited
186 -- range of priorities available in OpenVMS.
188 -- To replace the default values of the Underlying_Priorities mapping,
189 -- copy this source file into your build directory, edit the file to
190 -- reflect your desired behavior, and recompile with the command:
192 -- $ gcc -c -O3 -gnatpgn system.ads
194 -- then recompile the run-time parts that depend on this package:
196 -- $ gnatmake -a -gnatn -O3 <your application>
198 -- then force rebuilding your application if you need different options:
200 -- $ gnatmake -f <your options> <your application>
202 type Priorities_Mapping is array (Any_Priority) of Integer;
203 pragma Suppress_Initialization (Priorities_Mapping);
204 -- Suppress initialization in case gnat.adc specifies Normalize_Scalars
206 Underlying_Priorities : constant Priorities_Mapping :=
208 (Priority'First => 16,
225 Default_Priority => 24,
244 Interrupt_Priority => 31);
246 ----------------------------
247 -- Special VMS Interfaces --
248 ----------------------------
250 procedure Lib_Stop (I : in Integer);
251 pragma Interface (C, Lib_Stop);
252 pragma Import_Procedure (Lib_Stop, "LIB$STOP", Mechanism => (Value));
253 -- Interface to VMS condition handling. Used by RTSfind and pragma
254 -- {Import,Export}_Exception. Put here because this is the only
255 -- VMS specific package that doesn't drag in tasking.