{"ast_node_type":"variable","tokens":[{"end":68,"kind":"keyword","start":0,"text":"let"}]}
                let a_lane = a.value_lane(fx, lane).load_scalar(fx);
                let m_lane = fx.bcx.ins().band_imm(m_lane, 1);
                let b_lane = b.value_lane(fx, lane).load_scalar(fx);