CorrelatedValuePropagation miscompilation

[saethlin]

Like #139866 this is from a fuzzer that generates Rust MIR: https://github.com/cbeuw/rustlantis.

The Rust MIR reproducer is: https://godbolt.org/z/sb568G8r4

With this command line, the program runs:

rustc 9870897538617236803.rs -Copt-level=2 -Cllvm-args=-opt-bisect-limit=478

Any greater value of opt-bisect-limit runs CorrelatedValuePropagation on main and produces a program that just executes a ud2.

[nikic]

https://llvm.godbolt.org/z/s1sYaWbc3

; RUN: opt -S -passes=correlated-propagation < %s
define void @test() {
start:
  br label %loop

loop:
  %phi = phi i8 [ -69, %start ], [ 0, %loop3 ]
  br label %loop2

loop2:
  br label %loop3

loop3:
  switch i8 %phi, label %exit [
    i8 0, label %loop3
    i8 1, label %loop2
    i8 2, label %loop
  ]

exit:
  call void @foo()
  ret void
}

declare void @foo()

[nikic]

/cherry-pick 0f7cc41