1------------------------------------------------------------------------------
2--                                                                          --
3--                        GNAT RUN-TIME COMPONENTS                          --
4--                                                                          --
5--                               S Y S T E M                                --
6--                                                                          --
7--                                 S p e c                                  --
8--                          (GNU-Linux/RISC-V Version)                      --
9--                                                                          --
10--          Copyright (C) 1992-2021, 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
37package System is
38   pragma Pure;
39   --  Note that we take advantage of the implementation permission to make
40   --  this unit Pure instead of Preelaborable; see RM 13.7.1(15). In Ada
41   --  2005, this is Pure in any case (AI-362).
42
43   pragma No_Elaboration_Code_All;
44   --  Allow the use of that restriction in units that WITH this unit
45
46   type Name is (SYSTEM_NAME_GNAT);
47   System_Name : constant Name := SYSTEM_NAME_GNAT;
48
49   --  System-Dependent Named Numbers
50
51   Min_Int             : constant := -2 ** (Standard'Max_Integer_Size - 1);
52   Max_Int             : constant :=  2 ** (Standard'Max_Integer_Size - 1) - 1;
53
54   Max_Binary_Modulus    : constant := 2 ** Standard'Max_Integer_Size;
55   Max_Nonbinary_Modulus : constant := 2 ** Integer'Size - 1;
56
57   Max_Base_Digits       : constant := Long_Long_Float'Digits;
58   Max_Digits            : constant := Long_Long_Float'Digits;
59
60   Max_Mantissa          : constant := Standard'Max_Integer_Size - 1;
61   Fine_Delta            : constant := 2.0 ** (-Max_Mantissa);
62
63   Tick                  : constant := 0.000_001;
64
65   --  Storage-related Declarations
66
67   type Address is private;
68   pragma Preelaborable_Initialization (Address);
69   Null_Address : constant Address;
70
71   Storage_Unit : constant := 8;
72   Word_Size    : constant := Standard'Word_Size;
73   Memory_Size  : constant := 2 ** Word_Size;
74
75   --  Address comparison
76
77   function "<"  (Left, Right : Address) return Boolean;
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
83   pragma Import (Intrinsic, "<");
84   pragma Import (Intrinsic, "<=");
85   pragma Import (Intrinsic, ">");
86   pragma Import (Intrinsic, ">=");
87   pragma Import (Intrinsic, "=");
88
89   --  Other System-Dependent Declarations
90
91   type Bit_Order is (High_Order_First, Low_Order_First);
92   Default_Bit_Order : constant Bit_Order := Low_Order_First;
93   pragma Warnings (Off, Default_Bit_Order); -- kill constant condition warning
94
95   --  Priority-related Declarations (RM D.1)
96
97   Max_Priority           : constant Positive := 30;
98   Max_Interrupt_Priority : constant Positive := 31;
99
100   subtype Any_Priority       is Integer      range  0 .. 31;
101   subtype Priority           is Any_Priority range  0 .. 30;
102   subtype Interrupt_Priority is Any_Priority range 31 .. 31;
103
104   Default_Priority : constant Priority := 15;
105
106private
107
108   type Address is mod Memory_Size;
109   Null_Address : constant Address := 0;
110
111   --------------------------------------
112   -- System Implementation Parameters --
113   --------------------------------------
114
115   --  These parameters provide information about the target that is used
116   --  by the compiler. They are in the private part of System, where they
117   --  can be accessed using the special circuitry in the Targparm unit
118   --  whose source should be consulted for more detailed descriptions
119   --  of the individual switch values.
120
121   Backend_Divide_Checks     : constant Boolean := False;
122   Backend_Overflow_Checks   : constant Boolean := True;
123   Command_Line_Args         : constant Boolean := True;
124   Configurable_Run_Time     : constant Boolean := False;
125   Denorm                    : constant Boolean := True;
126   Duration_32_Bits          : constant Boolean := False;
127   Exit_Status_Supported     : constant Boolean := True;
128   Machine_Overflows         : constant Boolean := False;
129   Machine_Rounds            : constant Boolean := True;
130   Preallocated_Stacks       : constant Boolean := False;
131   Signed_Zeros              : constant Boolean := True;
132   Stack_Check_Default       : constant Boolean := False;
133   Stack_Check_Probes        : constant Boolean := True;
134   Stack_Check_Limits        : constant Boolean := False;
135   Support_Aggregates        : constant Boolean := True;
136   Support_Composite_Assign  : constant Boolean := True;
137   Support_Composite_Compare : constant Boolean := True;
138   Support_Long_Shifts       : constant Boolean := True;
139   Always_Compatible_Rep     : constant Boolean := False;
140   Suppress_Standard_Library : constant Boolean := False;
141   Use_Ada_Main_Program_Name : constant Boolean := False;
142   Frontend_Exceptions       : constant Boolean := False;
143   ZCX_By_Default            : constant Boolean := True;
144
145end System;
146