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<div class="moz-cite-prefix">On 7/25/2017 2:48 AM, Sam Parker via
llvm-dev wrote:<br>
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<p>Hi, </p>
<p><br>
</p>
<p>In running opt -indvars on the attached file, I see a massive
constant expression being generated (I stop opt once the
output file grows larger than 3GB). The example comes from
a reduced version an LNT test. I've been looking into constant
folding and indvar simplify to see if there's a way to limit
the depth of these expressions, but I haven't figured anything
out.</p>
<p><br>
</p>
<p>Could anyone shine some light into how to handle these
expressions? Could they be broken into multiple values? Or can
we limit the complexity of constant exprs?</p>
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<br>
It's a known issue that printing textual IR for constant expressions
which have the same operand multiple times can cause an exponential
explosion in the size of the text. Other passes generally handle
expressions like that without any problem, though.<br>
<br>
-Eli<br>
<pre class="moz-signature" cols="72">--
Employee of Qualcomm Innovation Center, Inc.
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project</pre>
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