<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/92274>92274</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            SimplifyCFGPass incorrectly hoists load before loop that can have zero iterations
        </td>
    </tr>

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

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

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

<pre>
    C++ reproducer:

```cpp
int ub(int &foo, int count) {
  delete &foo;
  int x = {};
  for (int i = 0; i < count; i++)
    x += foo;
  return x;
}
```

This code compiles to

```llvm
define dso_local noundef i32 @ub(int&, int)(ptr noundef nonnull align 4 dereferenceable(4) %foo, i32 noundef %count) local_unnamed_addr {
entry:
  tail call void @operator delete(void*)(ptr noundef nonnull %foo) #3
  %cmp4 = icmp sgt i32 %count, 0
  %0 = load i32, ptr %foo, align 4
  ; ^ unconditional UB: load from a dead pointer
  %1 = mul i32 %0, %count
  %x.0.lcssa = select i1 %cmp4, i32 %1, i32 0
  ret i32 %x.0.lcssa
}

```

turning conditional UB (on `count != 0`) into an unconditional one.

This is flagged as incorrect by alive2: https://alive2.llvm.org/ce/z/c3KXo9

Originaly discovered by @feedab1e
</pre>
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