{"ast_node_type":"other","tokens":[{"end":75,"kind":"keyword","start":0,"text":"//"}]}
                // This can only be reached in ConstProp and non-rustc-MIR.
            if from.checked_add(to).is_none_or(|to| to > len) {
                throw_ub!(BoundsCheckFailed { len, index: from.saturating_add(to) });