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-- S p e c -- 8-- -- 9-- Copyright (C) 2002-2013, Free Software Foundation, Inc. -- 10-- -- 11-- This specification is derived from the Ada Reference Manual for use with -- 12-- GNAT. The copyright notice above, and the license provisions that follow -- 13-- apply solely to the implementation dependent sections of this file. -- 14-- -- 15-- GNAT is free software; you can redistribute it and/or modify it under -- 16-- terms of the GNU General Public License as published by the Free Soft- -- 17-- ware Foundation; either version 3, or (at your option) any later ver- -- 18-- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- 19-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- 20-- or FITNESS FOR A PARTICULAR PURPOSE. -- 21-- -- 22-- As a special exception under Section 7 of GPL version 3, you are granted -- 23-- additional permissions described in the GCC Runtime Library Exception, -- 24-- version 3.1, as published by the Free Software Foundation. -- 25-- -- 26-- You should have received a copy of the GNU General Public License and -- 27-- a copy of the GCC Runtime Library Exception along with this program; -- 28-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -- 29-- <http://www.gnu.org/licenses/>. -- 30-- -- 31-- GNAT was originally developed by the GNAT team at New York University. -- 32-- Extensive contributions were provided by Ada Core Technologies Inc. -- 33-- -- 34------------------------------------------------------------------------------ 35 36-- Warning: declarations in this package are ambiguous with respect to the 37-- extra declarations that can be introduced into System using Extend_System. 38-- It is a good idea to avoid use clauses for this package. 39 40package System.Storage_Elements is 41 pragma Pure; 42 -- Note that we take advantage of the implementation permission to make 43 -- this unit Pure instead of Preelaborable; see RM 13.7.1(15). In Ada 2005, 44 -- this is Pure in any case (AI-362). 45 46 -- We also add the pragma Pure_Function to the operations in this package, 47 -- because otherwise functions with parameters derived from Address are 48 -- treated as non-pure by the back-end (see exp_ch6.adb). This is because 49 -- in many cases such a parameter is used to hide read/out access to 50 -- objects, and it would be unsafe to treat such functions as pure. 51 52 type Storage_Offset is range 53 -(2 ** (Integer'(Standard'Address_Size) - 1)) .. 54 +(2 ** (Integer'(Standard'Address_Size) - 1)) - Long_Long_Integer'(1); 55 -- Note: the reason for the Long_Long_Integer qualification here is to 56 -- avoid a bogus ambiguity when this unit is analyzed in an rtsfind 57 -- context. It may be possible to remove this in the future, but it is 58 -- certainly harmless in any case ??? 59 60 subtype Storage_Count is Storage_Offset range 0 .. Storage_Offset'Last; 61 62 type Storage_Element is mod 2 ** Storage_Unit; 63 for Storage_Element'Size use Storage_Unit; 64 65 pragma Universal_Aliasing (Storage_Element); 66 -- This type is used by the expander to implement aggregate copy 67 68 type Storage_Array is 69 array (Storage_Offset range <>) of aliased Storage_Element; 70 for Storage_Array'Component_Size use Storage_Unit; 71 72 -- Address arithmetic 73 74 function "+" (Left : Address; Right : Storage_Offset) return Address; 75 pragma Convention (Intrinsic, "+"); 76 pragma Inline_Always ("+"); 77 pragma Pure_Function ("+"); 78 79 function "+" (Left : Storage_Offset; Right : Address) return Address; 80 pragma Convention (Intrinsic, "+"); 81 pragma Inline_Always ("+"); 82 pragma Pure_Function ("+"); 83 84 function "-" (Left : Address; Right : Storage_Offset) return Address; 85 pragma Convention (Intrinsic, "-"); 86 pragma Inline_Always ("-"); 87 pragma Pure_Function ("-"); 88 89 function "-" (Left, Right : Address) return Storage_Offset; 90 pragma Convention (Intrinsic, "-"); 91 pragma Inline_Always ("-"); 92 pragma Pure_Function ("-"); 93 94 function "mod" 95 (Left : Address; 96 Right : Storage_Offset) return Storage_Offset; 97 pragma Convention (Intrinsic, "mod"); 98 pragma Inline_Always ("mod"); 99 pragma Pure_Function ("mod"); 100 101 -- Conversion to/from integers 102 103 type Integer_Address is mod Memory_Size; 104 105 function To_Address (Value : Integer_Address) return Address; 106 pragma Convention (Intrinsic, To_Address); 107 pragma Inline_Always (To_Address); 108 pragma Pure_Function (To_Address); 109 110 function To_Integer (Value : Address) return Integer_Address; 111 pragma Convention (Intrinsic, To_Integer); 112 pragma Inline_Always (To_Integer); 113 pragma Pure_Function (To_Integer); 114 115end System.Storage_Elements; 116