<html>
    <head>
      <base href="https://bugs.llvm.org/">
    </head>
    <body><span class="vcard"><a class="email" href="mailto:florian_hahn@apple.com" title="Florian Hahn <florian_hahn@apple.com>"> <span class="fn">Florian Hahn</span></a>
</span> changed
          <a class="bz_bug_link 
          bz_status_RESOLVED  bz_closed"
   title="RESOLVED FIXED - Incorrect optimization of memmove in DSE"
   href="https://bugs.llvm.org/show_bug.cgi?id=28013">bug 28013</a>
          <br>
             <table border="1" cellspacing="0" cellpadding="8">
          <tr>
            <th>What</th>
            <th>Removed</th>
            <th>Added</th>
          </tr>

         <tr>
           <td style="text-align:right;">Status</td>
           <td>NEW
           </td>
           <td>RESOLVED
           </td>
         </tr>

         <tr>
           <td style="text-align:right;">Resolution</td>
           <td>---
           </td>
           <td>FIXED
           </td>
         </tr>

         <tr>
           <td style="text-align:right;">CC</td>
           <td>
                
           </td>
           <td>florian_hahn@apple.com
           </td>
         </tr>

         <tr>
           <td style="text-align:right;">Fixed By Commit(s)</td>
           <td>
                
           </td>
           <td>737fa40ffad15482801cc60271aed40dd5de9c95
           </td>
         </tr></table>
      <p>
        <div>
            <b><a class="bz_bug_link 
          bz_status_RESOLVED  bz_closed"
   title="RESOLVED FIXED - Incorrect optimization of memmove in DSE"
   href="https://bugs.llvm.org/show_bug.cgi?id=28013#c1">Comment # 1</a>
              on <a class="bz_bug_link 
          bz_status_RESOLVED  bz_closed"
   title="RESOLVED FIXED - Incorrect optimization of memmove in DSE"
   href="https://bugs.llvm.org/show_bug.cgi?id=28013">bug 28013</a>
              from <span class="vcard"><a class="email" href="mailto:florian_hahn@apple.com" title="Florian Hahn <florian_hahn@apple.com>"> <span class="fn">Florian Hahn</span></a>
</span></b>
        <pre>Looks like this works as expected with clang version 11.0.0
(<a href="mailto:git@github.com">git@github.com</a>:llvm/llvm-project.git 14ff6c896344e0440fc1cf7921d96515a9d50d8d)


A quick git log search surfaced the commit below as probably fixing it

commit 737fa40ffad15482801cc60271aed40dd5de9c95
Author: Sanjoy Das <<a href="mailto:sanjoy@playingwithpointers.com">sanjoy@playingwithpointers.com</a>>
Date:   Tue Feb 20 23:19:34 2018 +0000

    [DSE] Don't DSE stores that subsequent memmove calls read from

    Summary:
    We used to remove the first memmove in cases like this:

      memmove(p, p+2, 8);
      memmove(p, p+2, 8);

    which is incorrect.  Fix this by changing isPossibleSelfRead to what was
most
    likely the intended behavior.

    Historical note: the buggy code was added in
<a href="https://reviews.llvm.org/rL120974">https://reviews.llvm.org/rL120974</a>
    to address PR8728.

    Reviewers: rsmith

    Subscribers: mcrosier, llvm-commits, jlebar

    Differential Revision: <a href="https://reviews.llvm.org/D43425">https://reviews.llvm.org/D43425</a>

    llvm-svn: 325641</pre>
        </div>
      </p>


      <hr>
      <span>You are receiving this mail because:</span>

      <ul>
          <li>You are on the CC list for the bug.</li>
      </ul>
    </body>
</html>