IMM_0
if (info->matchflags & IMM_0) {
INSN_F3("fence.i", MISCMEM_FENCEI, RD_0 | RS1_0 | IMM_0, 0),
INSN_F3("nop", OP_ADDSUB, RD_0 | RS1_0 | IMM_0, 0),