DITOREG
DITOREG(dval, MIPSInst_RT(ir));
DITOREG(xcp->regs[MIPSInst_RT(ir)], MIPSInst_RD(ir));
DITOREG(val, MIPSInst_FD(ir));
DITOREG(rv.l, MIPSInst_FD(ir));
#define DPTOREG(dp, x) DITOREG((dp).bits, x)