<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
</head>
<body text="#000000" bgcolor="#FFFFFF">
<div class="moz-cite-prefix">On 07/15/2017 01:09 PM, Daniel Berlin
wrote:<br>
</div>
<blockquote type="cite"
cite="mid:CAF4BwTVXemkygXFRGXnqZFXZ_+2Xed7q-=hMPk9dgXZ7=+M=MA@mail.gmail.com">
<div dir="ltr">Which is, of course, precisely why I didn't suggest
that, it was Hal's straw man.<br>
</div>
</blockquote>
Ah, sorry for the misread then. Skimming the thread, that's exactly
what I thought you *were* arguing for. Glad to know we're in
agreement. <br>
<blockquote type="cite"
cite="mid:CAF4BwTVXemkygXFRGXnqZFXZ_+2Xed7q-=hMPk9dgXZ7=+M=MA@mail.gmail.com">
<div dir="ltr">
</div>
<span>
</span><br>
<div class="gmail_quote">
<div dir="ltr">On Sat, Jul 15, 2017, 12:26 PM Philip Reames <<a
href="mailto:listmail@philipreames.com" target="_blank"
moz-do-not-send="true">listmail@philipreames.com</a>>
wrote:<br>
</div>
<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex">
<div text="#000000" bgcolor="#FFFFFF">
<div
class="m_5533082446293145890m_4446434701631465268moz-cite-prefix">On
07/14/2017 11:46 AM, Hal Finkel via llvm-dev wrote:<br>
</div>
<blockquote type="cite">
<p><br>
</p>
<div
class="m_5533082446293145890m_4446434701631465268moz-cite-prefix">On
07/14/2017 01:38 PM, Daniel Berlin wrote:<br>
</div>
<blockquote type="cite">
<div dir="ltr">
<div class="gmail_extra">
<div class="gmail_quote">
<blockquote class="gmail_quote" style="margin:0 0
0 .8ex;border-left:1px #ccc
solid;padding-left:1ex">
<div bgcolor="#FFFFFF" text="#000000">
<div>
<div
class="m_5533082446293145890m_4446434701631465268h5"><br>
</div>
</div>
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>
</blockquote>
<div><br>
</div>
<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>
<div><br>
</div>
<div>IE "it's just another small patch!"</div>
</div>
</div>
</div>
</blockquote>
<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>
</blockquote>
</div>
<div text="#000000" bgcolor="#FFFFFF"> Just want to chime in
here in support of what Hal said. I strongly believe we
should not block incremental progress unless we have a plan
in place for a better design. In particular, part of being
able to come up with a better design is having multiple
people with recent knowledge of the system which needs
replaced and stopping evolution of the old system by
definition inhibits having such a group of people. <br>
</div>
<div text="#000000" bgcolor="#FFFFFF"> <br>
Philip<br>
</div>
</blockquote>
</div>
</blockquote>
<p><br>
</p>
</body>
</html>