1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
|
------------------------------------------------------------------------------
-- --
-- GNAT RUN-TIME COMPONENTS --
-- --
-- S Y S T E M --
-- --
-- S p e c --
-- (OpenVMS GCC_ZCX DEC Threads Version) --
-- --
-- Copyright (C) 2002-2005 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, 51 Franklin Street, Fifth Floor, --
-- Boston, MA 02110-1301, 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;
-- 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 private;
Null_Address : constant Address;
Storage_Unit : constant := 8;
Word_Size : constant := 32;
Memory_Size : constant := 2 ** 32;
-- 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, "=");
-- 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
type Address is mod Memory_Size;
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;
|
