File : fz_pred.adb
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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 -- --
16 -- See also http://trilema.com/2015/a-new-software-licensing-paradigm . --
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19
20 with W_Pred; use W_Pred;
21
22
23 package body FZ_Pred is
24
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26 -- Fundamental Predicate Operations on FZ (finite integers)
27 ---------------------------------------------------------------------------
28
29 -- 1 iff N == 0 (branch-free); else 0
30 function FZ_ZeroP(N : in FZ) return WBool is
31 A : WBool := 1;
32 begin
33 for i in N'Range loop
34 A := A and W_ZeroP(N(i));
35 end loop;
36 return A;
37 end FZ_ZeroP;
38
39
40 -- 1 iff N != 0 (branch-free); else 0
41 function FZ_NZeroP(N : in FZ) return WBool is
42 begin
43 return 1 xor FZ_ZeroP(N);
44 end FZ_NZeroP;
45
46
47 -- 1 iff N is odd
48 function FZ_OddP(N : in FZ) return WBool is
49 begin
50 return W_OddP(N(N'First));
51 end FZ_OddP;
52
53 end FZ_Pred;