<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 --- - NewGVN failure while verifying memory congruency"
   href="https://llvm.org/bugs/show_bug.cgi?id=31594">31594</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>NewGVN failure while verifying memory congruency
          </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>normal
          </td>
        </tr>

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

        <tr>
          <th>Component</th>
          <td>Scalar Optimizations
          </td>
        </tr>

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

        <tr>
          <th>Reporter</th>
          <td>davide@freebsd.org
          </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>I think this is a slight variation of PR31573.
  store i8 0, i8* %blah, align 1
and
  store i8 0, i8* %foo.lcssa, align 1
are believed to be congruent but they belong to two different congruence
classes, hence the assertion firing.


define void @patatino(i8* %blah, i32 %choice) {
entry:
  br label %while.cond

while.cond:
  %foo = phi i8* [ %blah, %entry ], [ null, %while.body ]
  switch i32 %choice, label %while.body [
    i32 -1, label %while.end
    i32 40, label %land.end
  ]

land.end:
  br label %while.end

while.body:
  br label %while.cond

while.end:
  %foo.lcssa = phi i8* [ %foo, %land.end ], [ %foo, %while.cond ]
  store i8 0, i8* %foo.lcssa, align 1
  %0 = load i8, i8* %blah, align 1
  %loaded = icmp eq i8 %0, 0
  store i8 0, i8* %blah, align 1
  ret void
}</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>