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------------------------------------------------------------------------------
-- --
-- GNAT RUN-TIME LIBRARY (GNARL) COMPONENTS --
-- --
-- S Y S T E M . V E C T O R S . B O O L E A N _ O P E R A T I O N S --
-- --
-- S p e c --
-- --
-- Copyright (C) 2002-2009, 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 contains functions for runtime operations on boolean vectors
package System.Vectors.Boolean_Operations is
pragma Pure;
-- Although in general the boolean operations on arrays of booleans are
-- identical to operations on arrays of unsigned words of the same size,
-- for the "not" operator this is not the case as False is typically
-- represented by 0 and true by 1.
function "not" (Item : Vectors.Vector) return Vectors.Vector;
-- The three boolean operations "nand", "nor" and "nxor" are needed
-- for cases where the compiler moves boolean array operations into
-- the body of the loop that iterates over the array elements.
-- Note the following equivalences:
-- (not X) or (not Y) = not (X and Y) = Nand (X, Y)
-- (not X) and (not Y) = not (X or Y) = Nor (X, Y)
-- (not X) xor (not Y) = X xor Y
-- X xor (not Y) = not (X xor Y) = Nxor (X, Y)
function Nand (Left, Right : Boolean) return Boolean;
function Nor (Left, Right : Boolean) return Boolean;
function Nxor (Left, Right : Boolean) return Boolean;
function Nand (Left, Right : Vectors.Vector) return Vectors.Vector;
function Nor (Left, Right : Vectors.Vector) return Vectors.Vector;
function Nxor (Left, Right : Vectors.Vector) return Vectors.Vector;
pragma Inline_Always ("not");
pragma Inline_Always (Nand);
pragma Inline_Always (Nor);
pragma Inline_Always (Nxor);
end System.Vectors.Boolean_Operations;
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