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<p> + llvm-dev, which got accidentally dropped - sorry for any
duplication<br>
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<p>Hi Sjoerd,<br>
</p>
<blockquote type="cite"
cite="mid:DB6PR0801MB1990DC2BFF2608D98B299E47FC150@DB6PR0801MB1990.eurprd08.prod.outlook.com">
<div style="font-family:Calibri,Arial,Helvetica,sans-serif;
font-size:12pt; color:rgb(0,0,0)"> There was a VPlan
round-table at the US LLVM dev conference just a few weeks
ago, and I have linked in the people who were involved in this
as cost-modeling was one of the topics that was discussed. You
may have seen this already, but Dave started doing some work
in this area recently:</div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif;
font-size:12pt; color:rgb(0,0,0)"> <br>
</div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif;
font-size:12pt; color:rgb(0,0,0)"> <a
href="https://reviews.llvm.org/D89322" id="LPlnk562185"
moz-do-not-send="true">https://reviews.llvm.org/D89322</a></div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif;
font-size:12pt; color:rgb(0,0,0)"> <a
href="https://reviews.llvm.org/D89323" id="LPlnk661500"
moz-do-not-send="true">https://reviews.llvm.org/D89323</a><br>
</div>
</blockquote>
That's good to know, thanks for linking the experts!<br>
<blockquote type="cite"
cite="mid:DB6PR0801MB1990DC2BFF2608D98B299E47FC150@DB6PR0801MB1990.eurprd08.prod.outlook.com">
<div style="font-family:Calibri,Arial,Helvetica,sans-serif;
font-size:12pt; color:rgb(0,0,0)"> </div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif;
font-size:12pt; color:rgb(0,0,0)"> Just some first high-level
remarks on your proposal: I think work in this area would be
very valuable and solve a real problem that we currently have.
If you plan to choose this as a subject for a master's thesis,
you probably need to think about how big of a task this is and
having some motivating examples would be good too (but you
mentioned some already). To me it sounds like a big task that
needs a lot of plumbing in VPlan, but that's why having this
discussion here is interesting and hopefully people with more
VPlan experience can provide insights.<br>
</div>
</blockquote>
<p>You are right and I am fully aware that building a fully
functional cost model for VPlan might be a very big task, well
beyond the scope of a master thesis. But right now there isn't
even clear documentation of how exactly such a cost model should
look like, and I think it is an interesting and important topic
to explore. If I end up with a good idea , a thesis that
discusses the topic so there finally is some documentation, and
a proof-of-concept implementation, I hope that would already be
of some value and interest to the community.<br>
<br>
But yes, good examples are needed - that's one reason for this
RFC, as of course my experience in the matter is very localised
to a specific kind of instructions, and I am sure many members
of the community have met other issues that could help painting
a better picture of what should be done.<br>
<br>
Best,<br>
Anna<br>
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