1------------------------------------------------------------------------------
2--                                                                          --
3--                        GNAT RUN-TIME COMPONENTS                          --
4--                                                                          --
5--                               S Y S T E M                                --
6--                                                                          --
7--                                 S p e c                                  --
8--                            (Compiler Version)                            --
9--                                                                          --
10--          Copyright (C) 1992-2014 Free Software Foundation, Inc.          --
11--                                                                          --
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. --
15--                                                                          --
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 3,  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.                                     --
22--                                                                          --
23-- As a special exception under Section 7 of GPL version 3, you are granted --
24-- additional permissions described in the GCC Runtime Library Exception,   --
25-- version 3.1, as published by the Free Software Foundation.               --
26--                                                                          --
27-- You should have received a copy of the GNU General Public License and    --
28-- a copy of the GCC Runtime Library Exception along with this program;     --
29-- see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see    --
30-- <http://www.gnu.org/licenses/>.                                          --
31--                                                                          --
32-- GNAT was originally developed  by the GNAT team at  New York University. --
33-- Extensive contributions were provided by Ada Core Technologies Inc.      --
34--                                                                          --
35------------------------------------------------------------------------------
36
37--  This version is for RTEMS.  It is based as closely as possible on the
38--  generic version with the following exceptions:
39--      + priority definitions
40
41package System is
42   pragma Pure;
43   --  Note that we take advantage of the implementation permission to make
44   --  this unit Pure instead of Preelaborable; see RM 13.7.1(15). In Ada
45   --  2005, this is Pure in any case (AI-362).
46
47   type Name is (SYSTEM_NAME_GNAT);
48   System_Name : constant Name := SYSTEM_NAME_GNAT;
49
50   --  System-Dependent Named Numbers
51
52   Min_Int               : constant := Long_Long_Integer'First;
53   Max_Int               : constant := Long_Long_Integer'Last;
54
55   Max_Binary_Modulus    : constant := 2 ** Long_Long_Integer'Size;
56   Max_Nonbinary_Modulus : constant := Integer'Last;
57
58   Max_Base_Digits       : constant := Long_Long_Float'Digits;
59   Max_Digits            : constant := Long_Long_Float'Digits;
60
61   Max_Mantissa          : constant := 63;
62   Fine_Delta            : constant := 2.0 ** (-Max_Mantissa);
63
64   Tick                  : constant := 0.01;
65
66   --  Storage-related Declarations
67
68   type Address is private;
69   pragma Preelaborable_Initialization (Address);
70   Null_Address : constant Address;
71
72   Storage_Unit : constant := Standard'Storage_Unit;
73   Word_Size    : constant := Standard'Word_Size;
74   Memory_Size  : constant := 2 ** Standard'Address_Size;
75
76   --  Address comparison
77
78   function "<"  (Left, Right : Address) return Boolean;
79   function "<=" (Left, Right : Address) return Boolean;
80   function ">"  (Left, Right : Address) return Boolean;
81   function ">=" (Left, Right : Address) return Boolean;
82   function "="  (Left, Right : Address) return Boolean;
83
84   pragma Import (Intrinsic, "<");
85   pragma Import (Intrinsic, "<=");
86   pragma Import (Intrinsic, ">");
87   pragma Import (Intrinsic, ">=");
88   pragma Import (Intrinsic, "=");
89
90   --  Other System-Dependent Declarations
91
92   type Bit_Order is (High_Order_First, Low_Order_First);
93   Default_Bit_Order : constant Bit_Order :=
94                         Bit_Order'Val (Standard'Default_Bit_Order);
95   pragma Warnings (Off, Default_Bit_Order); -- kill constant condition warning
96
97   --  Priority-related Declarations (RM D.1)
98
99   --  RTEMS POSIX threads support 256 priority levels with 255 being
100   --  logically the most important. Levels 0 and 255 are reserved.
101   --
102   --  255        is reserved for RTEMS system tasks
103   --  247 - 254  correspond to hardware interrupt levels 0 .. 7
104   --  246        is a catchall default "interrupt" priority for signals,
105   --             allowing higher priority than normal tasks, but lower than
106   --             hardware priority levels.  Protected Object ceilings can
107   --             override these values.
108   --  245        is used by the Interrupt_Manager task
109   --  0          is reserved for the RTEMS IDLE task and really should not
110   --             be accessible from Ada but GNAT initializes
111   --             Current_Priority to 0 so it must be valid
112
113   Max_Priority           : constant Positive := 244;
114   Max_Interrupt_Priority : constant Positive := 254;
115
116   subtype Any_Priority       is Integer      range   0 .. 254;
117   subtype Priority           is Any_Priority range   0 .. 244;
118   subtype Interrupt_Priority is Any_Priority range 245 .. 254;
119
120   Default_Priority : constant Priority := 122;
121
122private
123
124   type Address is mod Memory_Size;
125   Null_Address : constant Address := 0;
126
127   --------------------------------------
128   -- System Implementation Parameters --
129   --------------------------------------
130
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.
136
137   Backend_Divide_Checks     : constant Boolean := False;
138   Backend_Overflow_Checks   : constant Boolean := False;
139   Command_Line_Args         : constant Boolean := True;
140   Configurable_Run_Time     : constant Boolean := False;
141   Denorm                    : constant Boolean := True;
142   Duration_32_Bits          : constant Boolean := False;
143   Exit_Status_Supported     : constant Boolean := True;
144   Fractional_Fixed_Ops      : constant Boolean := False;
145   Frontend_Layout           : constant Boolean := False;
146   Machine_Overflows         : constant Boolean := False;
147   Machine_Rounds            : constant Boolean := True;
148   Preallocated_Stacks       : constant Boolean := False;
149   Signed_Zeros              : constant Boolean := True;
150   Stack_Check_Default       : constant Boolean := False;
151   Stack_Check_Probes        : constant Boolean := False;
152   Stack_Check_Limits        : constant Boolean := False;
153   Support_64_Bit_Divides    : constant Boolean := True;
154   Support_Aggregates        : constant Boolean := True;
155   Support_Composite_Assign  : constant Boolean := True;
156   Support_Composite_Compare : constant Boolean := True;
157   Support_Long_Shifts       : constant Boolean := True;
158   Always_Compatible_Rep     : constant Boolean := True;
159   Suppress_Standard_Library : constant Boolean := False;
160   Use_Ada_Main_Program_Name : constant Boolean := False;
161   ZCX_By_Default            : constant Boolean := False;
162
163end System;
164