{"ast_node_type":"variable","tokens":[{"end":63,"kind":"keyword","start":0,"text":"let"}]}
                let a_idx = fx.bcx.ins().band_imm(b_lane, 0xf);
                let is_zero = fx.bcx.ins().band_imm(b_lane, 0x80);
                let a_idx = fx.bcx.ins().uextend(fx.pointer_type, a_idx);