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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 - LLVM 12 regression: AArch64 backend generates incorrect code for ashr <i8 x 16>"
   href="https://bugs.llvm.org/show_bug.cgi?id=49904">49904</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>LLVM 12 regression: AArch64 backend generates incorrect code for ashr <i8 x 16>
          </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>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>Backend: AArch64
          </td>
        </tr>

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

        <tr>
          <th>Reporter</th>
          <td>amanieu@gmail.com
          </td>
        </tr>

        <tr>
          <th>CC</th>
          <td>arnaud.degrandmaison@arm.com, llvm-bugs@lists.llvm.org, smithp352@googlemail.com, Ties.Stuij@arm.com
          </td>
        </tr></table>
      <p>
        <div>
        <pre>IR:

define <16 x i8> @simd_ashr(<16 x i8> %a, <16 x i8> %b) {
start:
  %0 = ashr <16 x i8> %a, %b
  ret <16 x i8> %0
}

llc -march=aarch64 -global-isel=1 -O0 test.ll

simd_ashr:                              // @simd_ashr
// %bb.0:                               // %start
        neg     v1.8h, v1.8h
        sshl    v0.16b, v0.16b, v1.16b
        ret

The neg instruction should be using .16b instead of .8h.</pre>
        </div>
      </p>


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