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    <p>Something tells me I should purchase that book - I sense it could
      reveal some interesting insights.</p>
    <p>Note that while I understand the concept of turning integer
      division into multiplication (indeed, I implemented the first
      version into x86 before it was improved with the
      "calc_divconst_magic_unsigned" routine, and then implemented it
      for AArch64), the algorithm that is used in
      "calc_divconst_magic_unsigned" I don't quite get if just for the
      lack of comments and references, although I am studying it more
      closely.</p>
    <p>Still, I figure I'll put down Hacker's Delight as a future
      purchase so I have a reputable source rather than just an online
      one (I know there's one somewhere that isn't behind a paywall).<br>
    </p>
    <p>Gareth aka. Kit<br>
    </p>
    <div class="moz-cite-prefix">On 20/08/2021 18:46, Marģers . via
      fpc-devel wrote:<br>
    </div>
    <blockquote type="cite"
      cite="mid:1629481576.611fea6862541@mail.inbox.lv">
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      <blockquote> is there a reference to the algorithm that's used to
        calculate the<br>
        reciprocal constants used in the integer division optimisations
        for x86 and AArch64?</blockquote>
      <br>
      Hacker’s Delight<br>
      Second Edition<br>
      Henry S. Warren, Jr.<br>
      <br>
       
      <br>
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      <pre class="moz-quote-pre" wrap="">_______________________________________________
fpc-devel maillist  -  <a class="moz-txt-link-abbreviated" href="mailto:fpc-devel@lists.freepascal.org">fpc-devel@lists.freepascal.org</a>
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</pre>
    </blockquote>
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