NSI
{"subic", OP(12), OP_MASK, PPCCOM, PPCVLE, {RT, RA, NSI}},
{"subic.", OP(13), OP_MASK, PPCCOM, PPCVLE, {RT, RA, NSI}},
{"subi", OP(14), OP_MASK, PPCCOM, PPCVLE, {RT, RA0, NSI}},
#define NSISIGNOPT NSI + 1
{"e_sub16i", OP(7), OP_MASK, PPCVLE, 0, {RT, RA, NSI}},