<div dir="ltr">Every instance of a particular Constant type+value should use the same object. There are uniquing maps in the LLVMContext that are checked when any of the Constant*::get methods are called. If the constant has already been created that object will be reused.<div><br></div><div>We rely on this to check equality of constants by doing only a pointer compare in many places.</div></div><div class="gmail_extra"><br clear="all"><div><div class="gmail_signature" data-smartmail="gmail_signature">~Craig</div></div>
<br><div class="gmail_quote">On Wed, Aug 9, 2017 at 11:38 AM, John Criswell via llvm-dev <span dir="ltr"><<a href="mailto:llvm-dev@lists.llvm.org" target="_blank">llvm-dev@lists.llvm.org</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div bgcolor="#FFFFFF" text="#000000">
<div class="m_6328358091205155845moz-cite-prefix">On 8/9/17 1:23 PM, Siddharth Bhat via
llvm-dev wrote:<br>
</div>
<blockquote type="cite">
<div dir="ltr">As the question asks. IIRC, I have only seen
constants use to:
<div><br>
</div>
<div>1. setup globals</div>
<div>2. as "constant parameters" to instructions. </div>
<div><br>
</div>
<div>In both these cases, from what I understand, they will have
a single use. Is it possible to create a Constant with
multiple use(r)s?</div>
</div>
</blockquote>
<br>
I am nearly positive that constants can be used more than once.
They subclass from Value. I am sure that you can create a test
program that uses the same constant value in different places and
see if it generates one ConstantInt or multiple ConstantInts for the
same constant integer.<br>
<br>
Regards,<br>
<br>
John Criswell<br>
<br>
<blockquote type="cite">
<div dir="ltr">
<div><br>
</div>
<div>Thanks,</div>
<div>Siddharth</div><span class="HOEnZb"><font color="#888888">
</font></span></div><span class="HOEnZb"><font color="#888888">
<div dir="ltr">-- <br>
</div>
<div class="m_6328358091205155845gmail_signature" data-smartmail="gmail_signature">
<div dir="ltr">Sending this from my phone, please excuse any
typos!</div>
</div>
<br>
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<br>
<p><br>
</p>
<pre class="m_6328358091205155845moz-signature" cols="72">--
John Criswell
Assistant Professor
Department of Computer Science, University of Rochester
<a class="m_6328358091205155845moz-txt-link-freetext" href="http://www.cs.rochester.edu/u/criswell" target="_blank">http://www.cs.rochester.edu/u/<wbr>criswell</a></pre>
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