# Finite Field Arithmetic

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2 ------------------------------------------------------------------------------
3 -- This file is part of 'Finite Field Arithmetic', aka 'FFA'.               --
4 --                                                                          --
5 -- (C) 2019 Stanislav Datskovskiy ( www.loper-os.org )                      --
6 -- http://wot.deedbot.org/17215D118B7239507FAFED98B98228A001ABFFC7.html     --
7 --                                                                          --
8 -- You do not have, nor can you ever acquire the right to use, copy or      --
9 -- distribute this software ; Should you use this software for any purpose, --
10 -- or copy and distribute it to anyone or in any manner, you are breaking   --
11 -- the laws of whatever soi-disant jurisdiction, and you promise to         --
12 -- continue doing so for the indefinite future. In any case, please         --
13 -- always : read and understand any software ; verify any PGP signatures    --
14 -- that you use - for any purpose.                                          --
15 --                                                                          --
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19
20 with Words;   use Words;
21 with FZ_Type; use FZ_Type;
22
23
24 package FZ_Basic is
25
26    pragma Pure;
27
28    -- Determine the Bitness of N
29    function FZ_Bitness(N : in FZ) return Bit_Count;
30    pragma Inline_Always(FZ_Bitness);
31
32    -- Determine the Bitness of the given FZ's Length
33    function FZ_Bitness_Log2(N : in FZ) return Positive;
34    pragma Inline_Always(FZ_Bitness_Log2);
35
36    -- N := 0
37    procedure FZ_Clear(N : out FZ);
38    pragma Inline_Always(FZ_Clear);
39
40    -- Set given FZ to a given truth value
41    procedure WBool_To_FZ(V : in WBool; N : out FZ);
42    pragma Inline_Always(WBool_To_FZ);
43
44    -- First word of N := Source
45    procedure FZ_Set_Head(N : out FZ; Source : in Word);
47
48    -- First word of N
49    function FZ_Get_Head(N : in FZ) return Word;