Finite Field Arithmetic

fz_qshft.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_QShft is
  25    
  26    pragma Pure;
  27    
  28    -- Constant-time subword shift, for where there is no barrel shifter
  29    procedure FZ_Quiet_ShiftRight_SubW_Soft(N        : in FZ;
  30                                            ShiftedN : in out FZ;
  31                                            Count    : in WBit_Index);
  32    pragma Inline_Always(FZ_Quiet_ShiftRight_SubW_Soft);
  33    
  34    -- Constant-time subword shift, for where there is no barrel shifter
  35    procedure FZ_Quiet_ShiftLeft_SubW_Soft(N        : in FZ;
  36                                           ShiftedN : in out FZ;
  37                                           Count    : in WBit_Index);
  38    pragma Inline_Always(FZ_Quiet_ShiftLeft_SubW_Soft);
  39    
  40    -- Constant-time arbitrary right-shift.
  41    procedure FZ_Quiet_ShiftRight(N        : in     FZ;
  42                                  ShiftedN : in out FZ;
  43                                  Count    : in     FZBit_Index);
  44    pragma Inline_Always(FZ_Quiet_ShiftRight);
  45    
  46    -- Constant-time arbitrary left-shift.
  47    procedure FZ_Quiet_ShiftLeft(N        : in     FZ;
  48                                 ShiftedN : in out FZ;
  49                                 Count    : in     FZBit_Index);
  50    pragma Inline_Always(FZ_Quiet_ShiftLeft);
  51    
  52 end FZ_QShft;