<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/65195>65195</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            We should drop nonnull, range, and align metadata when speculating if the poison value may trigger UB.
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            miscompilation,
            llvm:optimizations
      </td>
    </tr>

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

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

<pre>
    I tried this IR:
```llvm
define i32 @foo(i1 %c, ptr dereferenceable(8) align 8 %p) {
entry:
  br i1 %c, label %if, label %join

if:
 %v = load i32, ptr %p, !range !{i32 0, i32 10}
  %cv = icmp eq i32 %v, 1
  br i1 %cv, label %join, label %exit

join:
  %phi = phi i32 [ %v, %if ], [ 0, %entry ]
  ret i32 %phi

exit:
  ret i32 0
}
```

The current 17-rc version preserved `range` metadata. This poison will trigger UB on `br`.
https://llvm.godbolt.org/z/xrGPYrv1n.

Bisected 53500e333d35062942065d55364c45d97f03eac0. cc @nikic 

End-to-end mis-compilation is https://github.com/rust-lang/rust/issues/115385.
</pre>
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