File : fz_shift.ads
1 ------------------------------------------------------------------------------
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 . --
17 ------------------------------------------------------------------------------
18 ------------------------------------------------------------------------------
19
20 with Words; use Words;
21 with FZ_Type; use FZ_Type;
22
23
24 package FZ_Shift is
25
26 pragma Pure;
27
28 --------------------------------------------------------------
29 -- WARNING: These ops are not precondition-shielded, and
30 -- must never be directly exposed via the user API ( ffa.ads )
31 --------------------------------------------------------------
32
33 --------------------------------------------------------------
34 -- Shift Right
35 --------------------------------------------------------------
36
37 -- ShiftedN := N >> Count (with Overflow Input and Output)
38 -- WARNING: OF_in MUST be of valid bit-width for the shift!
39 procedure FZ_ShiftRight_O_I(N : in FZ;
40 ShiftedN : out FZ;
41 Count : in WBit_Index;
42 Overflow : out Word;
43 OF_in : in Word);
44 pragma Inline_Always(FZ_ShiftRight_O_I);
45
46 -- ShiftedN := N >> Count (with Overflow Output only)
47 procedure FZ_ShiftRight_O(N : in FZ;
48 ShiftedN : out FZ;
49 Count : in WBit_Index;
50 Overflow : out Word);
51 pragma Inline_Always(FZ_ShiftRight_O);
52
53 -- ShiftedN := N >> Count (no Overflow output or input)
54 procedure FZ_ShiftRight(N : in FZ;
55 ShiftedN : out FZ;
56 Count : in WBit_Index);
57 pragma Inline_Always(FZ_ShiftRight);
58
59 --------------------------------------------------------------
60 -- Shift Left
61 --------------------------------------------------------------
62
63 -- ShiftedN := N << Count (with Overflow Input and Output)
64 -- WARNING: OF_in MUST be of valid bit-width for the shift!
65 procedure FZ_ShiftLeft_O_I(N : in FZ;
66 ShiftedN : out FZ;
67 Count : in WBit_Index;
68 Overflow : out Word;
69 OF_in : in Word);
70 pragma Inline_Always(FZ_ShiftLeft_O_I);
71
72 -- ShiftedN := N << Count (with Overflow Output only)
73 procedure FZ_ShiftLeft_O(N : in FZ;
74 ShiftedN : out FZ;
75 Count : in WBit_Index;
76 Overflow : out Word);
77 pragma Inline_Always(FZ_ShiftLeft_O);
78
79 -- ShiftedN := N << Count (no Overflow output or input)
80 procedure FZ_ShiftLeft(N : in FZ;
81 ShiftedN : out FZ;
82 Count : in WBit_Index);
83 pragma Inline_Always(FZ_ShiftLeft);
84
85 end FZ_Shift;