<div dir="ltr"><div dir="ltr"><div>Hi David,</div><div><br></div><div>Your proposal looks sensible to me. I understand that for reasons of evolution of the pragma, you chose to give it `fixed` semantics if no explicit mark of vectorisation style appears, right?<br></div><div><br></div><div>Is this something in the future we'd want to relax? This way the target could also pick the best vectorization style (borrowing Sjoerd's terminology here). <br></div><div>Perhaps we could define a `vectorize_style(any)` as well. That would be the one used if no explicit `vectorize_style` is specified.<br></div><div></div><div></div></div><br><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div style="overflow-wrap: break-word;" lang="EN-GB"><div class="gmail-m_-5052617891530397558WordSection1">
<p class="MsoNormal"><u></u> <u></u></p>
<p class="MsoNormal">As a further extension I’d also like to permit vectorize_width(fixed|scalable) to<u></u><u></u></p>
<p class="MsoNormal">allow users to hint at the type of vector used without specifying the<u></u><u></u></p>
<p class="MsoNormal">vectorisation factor. Examples of this would be:<u></u><u></u></p>
<p class="MsoNormal"><u></u> <u></u></p>
<p class="gmail-m_-5052617891530397558MsoPlainText"> // Vectorize the loop with <N x eltty> for a profitable N<u></u><u></u></p>
<p class="gmail-m_-5052617891530397558MsoPlainText"> #pragma clang loop vectorize_width(fixed)<u></u><u></u></p>
<p class="gmail-m_-5052617891530397558MsoPlainText"></p>
<p class="gmail-m_-5052617891530397558MsoPlainText"> // Vectorize the loop with <vscale x N x eltty> for a profitable N<u></u><u></u></p>
<p class="gmail-m_-5052617891530397558MsoPlainText"> #pragma clang loop vectorize_width(scalable)</p></div></div></blockquote><div>In those cases, I imagine `vectorize_style` could be enough and we avoid having a `vectorize_width` that doesn't actually tell us the width (or the factor of the actual width, for scalables). But this falls in the "aesthetics" category, I think.</div><div><br></div><div>Kind regards,<br></div></div></div>