<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/143744>143744</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [clang] vsetvli/vsetivli does not permit lmul operand to be optional
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            clang
      </td>
    </tr>

    <tr>
      <th>Assignees</th>
      <td>
      </td>
    </tr>

    <tr>
      <th>Reporter</th>
      <td>
          ThinkOpenly
      </td>
    </tr>
</table>

<pre>
    The following instructions should all produce the same encoding:
```

[vsetvli.s.txt](https://github.com/user-attachments/files/20694598/vsetvli.s.txt)

[vsetvli.s.txt](https://github.com/user-attachments/files/20694603/vsetvli.s.txt)

vsetvli t0, a0, 192
vsetvli t0, a0, e8, m1, ta, ma
vsetvli t0, a0, e8, ta, ma
```

However, clang (20) does not accept the 3rd syntax that omits the lmul operand "m1", which is the default value:
```
$ clang -c vsetvli.s
vsetvli.s:21:25: error: operand must be e[8|16|32|64],m[1|2|4|8|f2|f4|f8],[ta|tu],[ma|mu]
        vsetvli t0, a0, e8, ta, ma
                        ^
```

Originally reported https://github.com/riscv-software-src/riscv-unified-db/pull/838.
</pre>
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