fixing pr42337
[official-gcc.git] / gcc / ada / s-stoele.adb
blob0bab843c1387d53faca52acf8ecea036521e7b42
1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT COMPILER COMPONENTS --
4 -- --
5 -- S Y S T E M . S T O R A G E _ E L E M E N T S --
6 -- --
7 -- B o d y --
8 -- --
9 -- Copyright (C) 1992-2009, Free Software Foundation, Inc. --
10 -- --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. --
17 -- --
18 -- As a special exception under Section 7 of GPL version 3, you are granted --
19 -- additional permissions described in the GCC Runtime Library Exception, --
20 -- version 3.1, as published by the Free Software Foundation. --
21 -- --
22 -- You should have received a copy of the GNU General Public License and --
23 -- a copy of the GCC Runtime Library Exception along with this program; --
24 -- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
25 -- <http://www.gnu.org/licenses/>. --
26 -- --
27 -- GNAT was originally developed by the GNAT team at New York University. --
28 -- Extensive contributions were provided by Ada Core Technologies Inc. --
29 -- --
30 ------------------------------------------------------------------------------
32 pragma Compiler_Unit;
34 with Ada.Unchecked_Conversion;
36 package body System.Storage_Elements is
38 pragma Suppress (All_Checks);
40 function To_Address is
41 new Ada.Unchecked_Conversion (Storage_Offset, Address);
42 function To_Offset is
43 new Ada.Unchecked_Conversion (Address, Storage_Offset);
45 -- Conversion to/from integers
47 -- These functions must be place first because they are inlined_always
48 -- and are used and inlined in other subprograms defined in this unit.
50 function To_Integer (Value : Address) return Integer_Address is
51 begin
52 return Integer_Address (Value);
53 end To_Integer;
55 function To_Address (Value : Integer_Address) return Address is
56 begin
57 return Address (Value);
58 end To_Address;
60 -- Address arithmetic
62 function "+" (Left : Address; Right : Storage_Offset) return Address is
63 begin
64 return To_Address (To_Integer (Left) + To_Integer (To_Address (Right)));
65 end "+";
67 function "+" (Left : Storage_Offset; Right : Address) return Address is
68 begin
69 return To_Address (To_Integer (To_Address (Left)) + To_Integer (Right));
70 end "+";
72 function "-" (Left : Address; Right : Storage_Offset) return Address is
73 begin
74 return To_Address (To_Integer (Left) - To_Integer (To_Address (Right)));
75 end "-";
77 function "-" (Left, Right : Address) return Storage_Offset is
78 begin
79 return To_Offset (To_Address (To_Integer (Left) - To_Integer (Right)));
80 end "-";
82 function "mod"
83 (Left : Address;
84 Right : Storage_Offset) return Storage_Offset
86 begin
87 if Right > 0 then
88 return Storage_Offset
89 (To_Integer (Left) mod Integer_Address (Right));
91 -- The negative case makes no sense since it is a case of a mod where
92 -- the left argument is unsigned and the right argument is signed. In
93 -- accordance with the (spirit of the) permission of RM 13.7.1(16),
94 -- we raise CE, and also include the zero case here. Yes, the RM says
95 -- PE, but this really is so obviously more like a constraint error.
97 else
98 raise Constraint_Error;
99 end if;
100 end "mod";
101 end System.Storage_Elements;