<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/155745>155745</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            llc silently ignores incorrect clobber constraint in inline asm
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            new issue
      </td>
    </tr>

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

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

<pre>
    The `NO_SUCH_REG` constraint in the following IR will be ignored by llc. Generally this should not be a problem, but producing an error might help people debugging.

```
target triple = "x86_64-unknown-linux-gnu"

define dso_local noundef i32 @test(i32 noundef %num) {
  %1 = call i32 asm sideeffect "add edx, $1; add $0, edx", "=r,r,~{edx},~{NO_SUCH_REG}"(i32 %num)
  ret i32 %1
}
``` 

godbolt: https://godbolt.org/z/8en1h9v6f
</pre>
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