<html>
    <head>
      <base href="https://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 --- - Crash with length 7 SIMD vectors"
   href="https://llvm.org/bugs/show_bug.cgi?id=27708">27708</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>Crash with length 7 SIMD vectors
          </td>
        </tr>

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

        <tr>
          <th>Version</th>
          <td>3.8
          </td>
        </tr>

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

        <tr>
          <th>OS</th>
          <td>All
          </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>schnetter@gmail.com
          </td>
        </tr>

        <tr>
          <th>CC</th>
          <td>llvm-bugs@lists.llvm.org
          </td>
        </tr>

        <tr>
          <th>Classification</th>
          <td>Unclassified
          </td>
        </tr></table>
      <p>
        <div>
        <pre>SIMD vectors of length 7 crash LLVM on x86-64 with AVX2.

This code
{{{
typedef long vlong7 __attribute__((__ext_vector_type__(7)));

vlong7 pvadd7(const vlong7 *restrict x, const vlong7 *restrict y) {
  return *x + *y;
}
}}}

leads to this error:
{{{
$ clang -S -march=native -Ofast llvm-simd.c
clang: error: unable to execute command: Segmentation fault: 11
clang: error: clang frontend command failed due to signal (use -v to see
invocation)
clang version 3.8.0 (branches/release_38 262722)
Target: x86_64-apple-darwin15.4.0
Thread model: posix
InstalledDir: /opt/local/libexec/llvm-3.8/bin
clang: note: diagnostic msg: PLEASE submit a bug report to
<a href="http://llvm.org/bugs/">http://llvm.org/bugs/</a> and include the crash backtrace, preprocessed source, and
associated run script.
clang: note: diagnostic msg: 
********************

PLEASE ATTACH THE FOLLOWING FILES TO THE BUG REPORT:
Preprocessed source(s) and associated run script(s) are located at:
clang: note: diagnostic msg:
/var/folders/gl/zvl8d6415vsbkd50nnll95k40000gs/T/llvm-simd-97992a.c
clang: note: diagnostic msg:
/var/folders/gl/zvl8d6415vsbkd50nnll95k40000gs/T/llvm-simd-97992a.sh
clang: note: diagnostic msg: 

********************
}}}

I see similar problems with all vector sizes N>4 && N==2^i-1.

I also see code generations problems (wrong code, i.e. code that calculates
wrong results) for vector sizes N>4 && N%4==3.</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>