lx_op
if (insn.dsp_format.func == lx_op) {
[insn_ldx] = {M(spec3_op, 0, 0, 0, ldx_op, lx_op), RS | RT | RD},
[insn_lwx] = {M(spec3_op, 0, 0, 0, lwx_op, lx_op), RS | RT | RD},