| ------------------------------------------------------------------------------ |
| -- -- |
| -- GNAT COMPILER COMPONENTS -- |
| -- -- |
| -- S Y S T E M . A D D R E S S _ O P E R A T I O N S -- |
| -- -- |
| -- S p e c -- |
| -- -- |
| -- Copyright (C) 2004-2021, 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. -- |
| -- -- |
| ------------------------------------------------------------------------------ |
| |
| -- This package provides arithmetic and logical operations on type Address. |
| -- It is intended for use by other packages in the System hierarchy. For |
| -- applications requiring this capability, see System.Storage_Elements or |
| -- the operations introduced in System.Aux_DEC; |
| |
| -- The reason we need this package is that arithmetic operations may not |
| -- be available in the case where type Address is non-private and the |
| -- operations have been made abstract in the spec of System (to avoid |
| -- inappropriate use by applications programs). In addition, the logical |
| -- operations may not be available if type Address is a signed integer. |
| |
| pragma Compiler_Unit_Warning; |
| |
| package System.Address_Operations is |
| pragma Pure; |
| |
| -- The semantics of the arithmetic operations are those that apply to |
| -- a modular type with the same length as Address, i.e. they provide |
| -- twos complement wrap around arithmetic treating the address value |
| -- as an unsigned value, with no overflow checking. |
| |
| -- Note that we do not use the infix names for these operations to |
| -- avoid problems with ambiguities coming from declarations in package |
| -- Standard (which may or may not be visible depending on the exact |
| -- form of the declaration of type System.Address). |
| |
| -- For addition, subtraction, and multiplication, the effect of overflow |
| -- is 2's complement wrapping (as though the type Address were unsigned). |
| |
| -- For division and modulus operations, the caller is responsible for |
| -- ensuring that the Right argument is non-zero, and the effect of the |
| -- call is not specified if a zero argument is passed. |
| |
| function AddA (Left, Right : Address) return Address; |
| function SubA (Left, Right : Address) return Address; |
| function MulA (Left, Right : Address) return Address; |
| function DivA (Left, Right : Address) return Address; |
| function ModA (Left, Right : Address) return Address; |
| |
| -- The semantics of the logical operations are those that apply to |
| -- a modular type with the same length as Address, i.e. they provide |
| -- bit-wise operations on all bits of the value (including the sign |
| -- bit if Address is a signed integer type). |
| |
| function AndA (Left, Right : Address) return Address; |
| function OrA (Left, Right : Address) return Address; |
| |
| pragma Inline_Always (AddA); |
| pragma Inline_Always (SubA); |
| pragma Inline_Always (MulA); |
| pragma Inline_Always (DivA); |
| pragma Inline_Always (ModA); |
| pragma Inline_Always (AndA); |
| pragma Inline_Always (OrA); |
| |
| end System.Address_Operations; |
