The real case where it matters is where the "if (foo) { ... }" test happens in a function that's been inlined into the caller, but not all the callers do the fo

The real case where it matters is where the "if (foo) { ... }" test happens in a function that's been inlined into the caller, but not all the callers do the foo->bar() dereference. So it's only being removed in some cases.