RV_I_IMM_11_0_OPOFF
(RV_X_MASK(x_, RV_I_IMM_11_0_OPOFF, RV_I_IMM_11_0_MASK)) | \
*itype_insn &= ~(RV_I_IMM_11_0_MASK << RV_I_IMM_11_0_OPOFF);
*itype_insn |= ((imm & RV_I_IMM_11_0_MASK) << RV_I_IMM_11_0_OPOFF);