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      <base href="https://bugs.llvm.org/">
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    <body><table border="1" cellspacing="0" cellpadding="8">
        <tr>
          <th>Bug ID</th>
          <td><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - [PPC] Suspicious repeated condition in PPCTargetLowering.LowerBUILD_VECTOR"
   href="https://bugs.llvm.org/show_bug.cgi?id=47942">47942</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>[PPC] Suspicious repeated condition in PPCTargetLowering.LowerBUILD_VECTOR
          </td>
        </tr>

        <tr>
          <th>Product</th>
          <td>libraries
          </td>
        </tr>

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

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

        <tr>
          <th>OS</th>
          <td>Windows NT
          </td>
        </tr>

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

        <tr>
          <th>Severity</th>
          <td>enhancement
          </td>
        </tr>

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

        <tr>
          <th>Component</th>
          <td>Backend: PowerPC
          </td>
        </tr>

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

        <tr>
          <th>Reporter</th>
          <td>llvm-dev@redking.me.uk
          </td>
        </tr>

        <tr>
          <th>CC</th>
          <td>llvm-bugs@lists.llvm.org, nemanja.i.ibm@gmail.com
          </td>
        </tr></table>
      <p>
        <div>
        <pre>Noticed by cppcheck:

// vsplti + srl self.
if (SextVal == (int)((unsigned)i >> TypeShiftAmt)) {
...
}

// vsplti + sra self.
if (SextVal == (int)((unsigned)i >> TypeShiftAmt)) {
...
}

The second condition is always dead code - its also suspicious that a "SextVal"
is being used for a logical shift right splat extraction.

Looking in a recent code coverage report, some of the other splat patterns are
not tested either:

<a href="http://lab.llvm.org:8080/coverage/coverage-reports/coverage/Users/buildslave/jenkins/workspace/coverage/llvm-project/llvm/lib/Target/PowerPC/PPCISelLowering.cpp.html">http://lab.llvm.org:8080/coverage/coverage-reports/coverage/Users/buildslave/jenkins/workspace/coverage/llvm-project/llvm/lib/Target/PowerPC/PPCISelLowering.cpp.html</a>

// t = vsplti c, result = vsldoi t, t, 2
// t = vsplti c, result = vsldoi t, t, 3</pre>
        </div>
      </p>


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