Fact propagation fails when combined with drop, panics, and memory swaps

[SUPERCILEX]

use std::mem;

struct Foo(Vec<u32>);

impl Drop for Foo {
    fn drop(&mut self) {
        if self.0.is_empty() {
            return;
        }

        let v = mem::take(&mut self.0);

        panic!("dead");
    }
}

pub fn foo() {
    let a = Foo(Vec::new());
    unsafe {unknown(9);}
}

extern "Rust" {
    fn unknown(x: i32) -> bool;
}

https://rust.godbolt.org/z/ra7bj7zf1

Related issue: #114532. Notice that in this case drop is called before ret so this code can't be eliminated yet (I think).