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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 - Stack parameter push order incorrect"
   href="https://bugs.llvm.org/show_bug.cgi?id=39446">39446</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>Stack parameter push order incorrect
          </td>
        </tr>

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

        <tr>
          <th>Version</th>
          <td>7.0
          </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>Backend: AVR
          </td>
        </tr>

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

        <tr>
          <th>Reporter</th>
          <td>tetsuya.ooka@dsn.rohm.co.jp
          </td>
        </tr>

        <tr>
          <th>CC</th>
          <td>llvm-bugs@lists.llvm.org
          </td>
        </tr></table>
      <p>
        <div>
        <pre>Created <span class=""><a href="attachment.cgi?id=21037" name="attach_21037" title="test code for reproduction">attachment 21037</a> <a href="attachment.cgi?id=21037&action=edit" title="test code for reproduction">[details]</a></span>
test code for reproduction

If optimize level is -O1, the order of pushing the last parameter and the
second parameter from last into stack is reversed. It leads incorrect result.

Reproduction procedure is to run the command below, where test.c is the
attached file.
clang --target=avr -O1 test.c -S -o test.S

In test.c, the main function calls function f with parameters
0,1,2,3,4,5,6,7,8,9,10 and 11.
But in test.S, the parameter pushing sequence is like below.
ldi     r24, 10
push    r24
ldi     r24, 11
ldi     r25, 0
push    r25
push    r24
ldi     r24, 9
ldi     r25, 0

I think it supposed to push 11, 10 then 9. But it pushes 10, 11 then 9.

Can anyone fix this problem?
Thank you.</pre>
        </div>
      </p>


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