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From: Bill Findlay <findlaybill@blueyonder.co.uk>
Newsgroups: comp.lang.ada
Subject: Re: Creating several types from a base type and conversion
Date: Sat, 18 Jan 2020 18:20:40 +0000
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Date: 2020-01-18T18:20:40+00:00
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On 18 Jan 2020, Jeffrey R. Carter wrote (in 
article<qvvaqs$k9p$1@dont-email.me>):

> On 1/18/20 3:56 PM, Bill Findlay wrote:
> >
> > Use the type:
> >
> > mod 2**30
> >
> > which provides all the bit handling you need.
>
> Except for shifts and rotations, which most instruction sets provide.
> Shifts can be replaced by multiplication and division by powers of two.
> Rotations are a little more complex.

Or, using GNAT, e.g.:

type word is mod 2**30;

subtype word_shift_length is Natural range 0..30;

function shift_word_left (W : word; amount : word_shift_length)
return KDF9.word;

function shift_word_right (W : word; amount : word_shift_length)
return KDF9.word;

function rotate_word_left (W : word; amount : word_shift_length)
return KDF9.word;

function rotate_word_right (W : word; amount : word_shift_length)
return KDF9.word;

All done.

-- 
Bill Findlay