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    <head>
      <base href="http://llvm.org/bugs/" />
    </head>
    <body><table border="1" cellspacing="0" cellpadding="8">
        <tr>
          <th>Bug ID</th>
          <td><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW --- - loop-vectorizer regression on x86-32"
   href="http://llvm.org/bugs/show_bug.cgi?id=16592">16592</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>loop-vectorizer regression on x86-32
          </td>
        </tr>

        <tr>
          <th>Product</th>
          <td>new-bugs
          </td>
        </tr>

        <tr>
          <th>Version</th>
          <td>trunk
          </td>
        </tr>

        <tr>
          <th>Hardware</th>
          <td>PC
          </td>
        </tr>

        <tr>
          <th>OS</th>
          <td>Linux
          </td>
        </tr>

        <tr>
          <th>Status</th>
          <td>NEW
          </td>
        </tr>

        <tr>
          <th>Severity</th>
          <td>normal
          </td>
        </tr>

        <tr>
          <th>Priority</th>
          <td>P
          </td>
        </tr>

        <tr>
          <th>Component</th>
          <td>new bugs
          </td>
        </tr>

        <tr>
          <th>Assignee</th>
          <td>unassignedbugs@nondot.org
          </td>
        </tr>

        <tr>
          <th>Reporter</th>
          <td>baldrick@free.fr
          </td>
        </tr>

        <tr>
          <th>CC</th>
          <td>llvmbugs@cs.uiuc.edu
          </td>
        </tr>

        <tr>
          <th>Classification</th>
          <td>Unclassified
          </td>
        </tr></table>
      <p>
        <div>
        <pre>Created <span class=""><a href="attachment.cgi?id=10856" name="attach_10856" title="IR that used to loop-vectorize">attachment 10856</a> <a href="attachment.cgi?id=10856&action=edit" title="IR that used to loop-vectorize">[details]</a></span>
IR that used to loop-vectorize

This

void bar(float *A, float* B, float K) {
  int i;
  for (i = 0; i < 64; ++i)
    A[i] *= B[i] + K;
}

used to vectorize with dragonegg on x86-32 (with -O3 -msse), but stopped
vectorizing recently.  Note that it still vectorizes with clang, I think
because clang outputs inbounds GEPs for the array accesses while dragonegg
doesn't.

It still vectorizes on x86-64, but it's not clear to me why it is better on 64
bit.

IR attached.</pre>
        </div>
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