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, 51 Franklin Street, Fifth Floor, --
25 -- Boston, MA 02110-1301, 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 make this
42 -- unit Pure instead of Preelaborable; see RM 13.7.1(15). In Ada 2005, this is
43 -- Pure in any case (AI-362).
45 type Name
is (SYSTEM_NAME_GNAT
);
46 System_Name
: constant Name
:= SYSTEM_NAME_GNAT
;
48 -- System-Dependent Named Numbers
50 Min_Int
: constant := Long_Long_Integer'First;
51 Max_Int
: constant := Long_Long_Integer'Last;
53 Max_Binary_Modulus
: constant := 2 ** Long_Long_Integer'Size;
54 Max_Nonbinary_Modulus
: constant := Integer'Last;
56 Max_Base_Digits
: constant := Long_Long_Float'Digits;
57 Max_Digits
: constant := Long_Long_Float'Digits;
59 Max_Mantissa
: constant := 63;
60 Fine_Delta
: constant := 2.0 ** (-Max_Mantissa
);
62 Tick
: constant := 0.01;
64 -- Storage-related Declarations
66 type Address
is new Long_Integer;
67 Null_Address
: constant Address
;
68 -- Although this is declared as an integer type, no arithmetic operations
69 -- are available (see abstract declarations below), and furthermore there
70 -- is special processing in the compiler that prevents the use of integer
71 -- literals with this type (use To_Address to convert integer literals).
73 -- Conversion to and from Short_Address is however freely permitted, and
74 -- is indeed the reason that Address is declared as an integer type. See
77 Storage_Unit
: constant := 8;
78 Word_Size
: constant := 64;
79 Memory_Size
: constant := 2 ** 64;
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;
87 function "=" (Left
, Right
: Address
) return Boolean;
89 pragma Import
(Intrinsic
, "<");
90 pragma Import
(Intrinsic
, "<=");
91 pragma Import
(Intrinsic
, ">");
92 pragma Import
(Intrinsic
, ">=");
93 pragma Import
(Intrinsic
, "=");
95 -- Abstract declarations for arithmetic operations on type address.
96 -- These declarations are needed when Address is non-private. They
97 -- avoid excessive visibility of arithmetic operations on address
98 -- which are typically available elsewhere (e.g. Storage_Elements)
99 -- and which would cause excessive ambiguities in application code.
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 "*" (Left
, Right
: Address
) return Address
is abstract;
105 function "mod" (Left
, Right
: Address
) return Address
is abstract;
107 -- Other System-Dependent Declarations
109 type Bit_Order
is (High_Order_First
, Low_Order_First
);
110 Default_Bit_Order
: constant Bit_Order
:= Low_Order_First
;
112 -- Priority-related Declarations (RM D.1)
114 Max_Priority
: constant Positive := 30;
115 Max_Interrupt_Priority
: constant Positive := 31;
117 subtype Any_Priority
is Integer range 0 .. 31;
118 subtype Priority
is Any_Priority
range 0 .. 30;
119 subtype Interrupt_Priority
is Any_Priority
range 31 .. 31;
121 Default_Priority
: constant Priority
:= 15;
125 Null_Address
: constant Address
:= 0;
127 --------------------------------------
128 -- System Implementation Parameters --
129 --------------------------------------
131 -- These parameters provide information about the target that is used
132 -- by the compiler. They are in the private part of System, where they
133 -- can be accessed using the special circuitry in the Targparm unit
134 -- whose source should be consulted for more detailed descriptions
135 -- of the individual switch values.
137 AAMP
: constant Boolean := False;
138 Backend_Divide_Checks
: constant Boolean := False;
139 Backend_Overflow_Checks
: constant Boolean := False;
140 Command_Line_Args
: constant Boolean := True;
141 Compiler_System_Version
: constant Boolean := False;
142 Configurable_Run_Time
: constant Boolean := False;
143 Denorm
: constant Boolean := False;
144 Duration_32_Bits
: constant Boolean := False;
145 Exit_Status_Supported
: constant Boolean := True;
146 Fractional_Fixed_Ops
: constant Boolean := False;
147 Frontend_Layout
: constant Boolean := False;
148 Functions_Return_By_DSP
: constant Boolean := False;
149 Machine_Overflows
: constant Boolean := False;
150 Machine_Rounds
: constant Boolean := True;
151 OpenVMS
: constant Boolean := True;
152 Preallocated_Stacks
: constant Boolean := False;
153 Signed_Zeros
: constant Boolean := True;
154 Stack_Check_Default
: constant Boolean := True;
155 Stack_Check_Probes
: constant Boolean := True;
156 Support_64_Bit_Divides
: constant Boolean := True;
157 Support_Aggregates
: constant Boolean := True;
158 Support_Composite_Assign
: constant Boolean := True;
159 Support_Composite_Compare
: constant Boolean := True;
160 Support_Long_Shifts
: constant Boolean := True;
161 Suppress_Standard_Library
: constant Boolean := False;
162 Use_Ada_Main_Program_Name
: constant Boolean := False;
163 ZCX_By_Default
: constant Boolean := True;
164 GCC_ZCX_Support
: constant Boolean := True;
165 Front_End_ZCX_Support
: constant Boolean := False;
167 -- Obsolete entries, to be removed eventually (bootstrap issues!)
169 High_Integrity_Mode
: constant Boolean := False;
170 Long_Shifts_Inlined
: constant Boolean := False;
172 --------------------------
173 -- Underlying Priorities --
174 ---------------------------
176 -- Important note: this section of the file must come AFTER the
177 -- definition of the system implementation parameters to ensure
178 -- that the value of these parameters is available for analysis
179 -- of the declarations here (using Rtsfind at compile time).
181 -- The underlying priorities table provides a generalized mechanism
182 -- for mapping from Ada priorities to system priorities. In some
183 -- cases a 1-1 mapping is not the convenient or optimal choice.
185 -- For DEC Threads OpenVMS, we use the full range of 31 priorities
186 -- in the Ada model, but map them by compression onto the more limited
187 -- range of priorities available in OpenVMS.
189 -- To replace the default values of the Underlying_Priorities mapping,
190 -- copy this source file into your build directory, edit the file to
191 -- reflect your desired behavior, and recompile with the command:
193 -- $ gcc -c -O3 -gnatpgn system.ads
195 -- then recompile the run-time parts that depend on this package:
197 -- $ gnatmake -a -gnatn -O3 <your application>
199 -- then force rebuilding your application if you need different options:
201 -- $ gnatmake -f <your options> <your application>
203 type Priorities_Mapping
is array (Any_Priority
) of Integer;
204 pragma Suppress_Initialization
(Priorities_Mapping
);
205 -- Suppress initialization in case gnat.adc specifies Normalize_Scalars
207 Underlying_Priorities
: constant Priorities_Mapping
:=
209 (Priority
'First => 16,
226 Default_Priority
=> 24,
245 Interrupt_Priority
=> 31);
247 ----------------------------
248 -- Special VMS Interfaces --
249 ----------------------------
251 procedure Lib_Stop
(I
: in Integer);
252 pragma Interface
(C
, Lib_Stop
);
253 pragma Import_Procedure
(Lib_Stop
, "LIB$STOP", Mechanism
=> (Value
));
254 -- Interface to VMS condition handling. Used by RTSfind and pragma
255 -- {Import,Export}_Exception. Put here because this is the only
256 -- VMS specific package that doesn't drag in tasking.