{"ast_node_type":"variable","tokens":[{"end":39,"kind":"keyword","start":0,"text":"let"}]}
                    let has_underflow =
                    let val = fx.bcx.ins().imul(lhs, rhs);
                        fx.bcx.ins().icmp_imm(IntCC::SignedLessThan, val, -(1 << (ty.bits() - 1)));