| ------------------------------------------------------------------------------ |
| -- -- |
| -- 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) 2002-2021, 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 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; |
