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------------------------------------------------------------------------------
-- --
-- GNAT COMPILER COMPONENTS --
-- --
-- S Y S T E M . S T O R A G E _ E L E M E N T S --
-- --
-- B o d y --
-- --
-- Copyright (C) 1992-2021, Free Software Foundation, Inc. --
-- --
-- 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 3, 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. --
-- --
-- As a special exception under Section 7 of GPL version 3, you are granted --
-- additional permissions described in the GCC Runtime Library Exception, --
-- version 3.1, as published by the Free Software Foundation. --
-- --
-- You should have received a copy of the GNU General Public License and --
-- a copy of the GCC Runtime Library Exception along with this program; --
-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
-- <http://www.gnu.org/licenses/>. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- --
------------------------------------------------------------------------------
pragma Compiler_Unit_Warning;
with Ada.Unchecked_Conversion;
package body System.Storage_Elements is
pragma Suppress (All_Checks);
-- Conversion to/from address
-- Note qualification below of To_Address to avoid ambiguities systems
-- where Address is a visible integer type.
function To_Address is
new Ada.Unchecked_Conversion (Storage_Offset, Address);
function To_Offset is
new Ada.Unchecked_Conversion (Address, Storage_Offset);
-- Conversion to/from integers
-- These functions must be place first because they are inlined_always
-- and are used and inlined in other subprograms defined in this unit.
----------------
-- To_Address --
----------------
function To_Address (Value : Integer_Address) return Address is
begin
return Address (Value);
end To_Address;
----------------
-- To_Integer --
----------------
function To_Integer (Value : Address) return Integer_Address is
begin
return Integer_Address (Value);
end To_Integer;
-- Address arithmetic
---------
-- "+" --
---------
function "+" (Left : Address; Right : Storage_Offset) return Address is
begin
return Storage_Elements.To_Address
(To_Integer (Left) + To_Integer (To_Address (Right)));
end "+";
function "+" (Left : Storage_Offset; Right : Address) return Address is
begin
return Storage_Elements.To_Address
(To_Integer (To_Address (Left)) + To_Integer (Right));
end "+";
---------
-- "-" --
---------
function "-" (Left : Address; Right : Storage_Offset) return Address is
begin
return Storage_Elements.To_Address
(To_Integer (Left) - To_Integer (To_Address (Right)));
end "-";
function "-" (Left, Right : Address) return Storage_Offset is
begin
return To_Offset (Storage_Elements.To_Address
(To_Integer (Left) - To_Integer (Right)));
end "-";
-----------
-- "mod" --
-----------
function "mod"
(Left : Address;
Right : Storage_Offset) return Storage_Offset
is
begin
if Right > 0 then
return Storage_Offset
(To_Integer (Left) mod Integer_Address (Right));
-- The negative case makes no sense since it is a case of a mod where
-- the left argument is unsigned and the right argument is signed. In
-- accordance with the (spirit of the) permission of RM 13.7.1(16),
-- we raise CE, and also include the zero case here. Yes, the RM says
-- PE, but this really is so obviously more like a constraint error.
else
raise Constraint_Error;
end if;
end "mod";
end System.Storage_Elements;