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ffa_ch9_exodus.kv       1 ------------------------------------------------------------------------------
ffa_ch9_exodus.kv       2 ------------------------------------------------------------------------------
ffa_ch9_exodus.kv       3 -- This file is part of 'Finite Field Arithmetic', aka 'FFA'.               --
ffa_ch9_exodus.kv       4 --                                                                          --
ffa_ch9_exodus.kv       5 -- (C) 2018 Stanislav Datskovskiy ( www.loper-os.org )                      --
ffa_ch9_exodus.kv       6 -- http://wot.deedbot.org/17215D118B7239507FAFED98B98228A001ABFFC7.html     --
ffa_ch9_exodus.kv       7 --                                                                          --
ffa_ch9_exodus.kv       8 -- You do not have, nor can you ever acquire the right to use, copy or      --
ffa_ch9_exodus.kv       9 -- distribute this software ; Should you use this software for any purpose, --
ffa_ch9_exodus.kv      10 -- or copy and distribute it to anyone or in any manner, you are breaking   --
ffa_ch9_exodus.kv      11 -- the laws of whatever soi-disant jurisdiction, and you promise to         --
ffa_ch9_exodus.kv      12 -- continue doing so for the indefinite future. In any case, please         --
ffa_ch9_exodus.kv      13 -- always : read and understand any software ; verify any PGP signatures    --
ffa_ch9_exodus.kv      14 -- that you use - for any purpose.                                          --
ffa_ch9_exodus.kv      15 --                                                                          --
ffa_ch9_exodus.kv      16 -- See also http://trilema.com/2015/a-new-software-licensing-paradigm .     --
ffa_ch9_exodus.kv      17 ------------------------------------------------------------------------------
ffa_ch9_exodus.kv      18 ------------------------------------------------------------------------------
ffa_ch9_exodus.kv      19 
ffa_ch9_exodus.kv      20 with Words; use Words;
ffa_ch9_exodus.kv      21 
ffa_ch9_exodus.kv      22 
ffa_ch9_exodus.kv      23 package W_Mul is
ffa_ch9_exodus.kv      24    
ffa_ch9_exodus.kv      25    pragma Pure;
ffa_ch9_exodus.kv      26    
ffa_ch9_exodus.kv      27    -- The bitness of a Half-Word
ffa_ch9_exodus.kv      28    HalfBitness : constant Positive := Bitness / 2;
ffa_ch9_exodus.kv      29    subtype HalfWord is Word range 0 .. 2**HalfBitness;
ffa_ch9_exodus.kv      30    
ffa_ch9_exodus.kv      31    -- The number of bytes in a Half-Word
ffa_ch9_exodus.kv      32    HalfByteness : constant Positive := Byteness / 2;
ffa_ch9_exodus.kv      33    
ffa_ch9_exodus.kv      34    -- Multiply half-words X and Y, producing a Word-sized product
ffa_ch9_exodus.kv      35    function Mul_HalfWord(X : in HalfWord; Y : in HalfWord) return Word;
ffa_ch9_exodus.kv      36    
ffa_ch9_exodus.kv      37    -- Get the bottom half of a Word
ffa_ch9_exodus.kv      38    function BottomHW(W : in Word) return HalfWord;
ffa_ch9_exodus.kv      39    
ffa_ch9_exodus.kv      40    -- Get the top half of a Word
ffa_ch9_exodus.kv      41    function TopHW(W : in Word) return HalfWord;
ffa_ch9_exodus.kv      42    
ffa_ch9_exodus.kv      43    -- Carry out X*Y mult, return lower word XY_LW and upper word XY_HW.
ffa_ch9_exodus.kv      44    procedure Mul_Word(X : in Word; Y : in Word; XY_LW : out Word; XY_HW : out Word);
ffa_ch9_exodus.kv      45    
ffa_ch9_exodus.kv      46 end W_Mul;