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<div class="moz-cite-prefix">On 07/14/2017 01:38 PM, Daniel Berlin
wrote:<br>
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Not sure about this last part. It is really going to
require work by us to rewrite things. :-) In the mean
time, I think we should go ahead with this.</div>
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<div>FWIW: My problem is, when put in this framework, we
will repeatedly make this same decision, this same way,
again and again, and never actually get even started on
fixing it :)</div>
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<div>IE "it's just another small patch!"</div>
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<br>
You're correct. However, as I'm sure you're aware, developer time is
not directly transferable in a way that makes any other decision
optimal. It's not like blocking all improvements to InstCombine will
cause a movement to appear to rewrite InstCombine. It will only
cause a shrink in the pool of developers with recent experience
working on InstCombine (and a lot of out-of-tree patches). Frankly,
we don't even have a concrete plan for how we'd do this, or even a
target design, and that's the first item on the critical path to a
rewrite. We should start an RFC and iterate on this until we have a
concrete plan and migration plan.<br>
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-Hal<br>
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<pre class="moz-signature" cols="72">--
Hal Finkel
Lead, Compiler Technology and Programming Languages
Leadership Computing Facility
Argonne National Laboratory</pre>
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