_REG_A6
uc.uc_mcontext.__gregs[_REG_A6] = sc->sc_fp;
mcp->__gregs[_REG_A6] = 0; /* Wipe out frame pointer. */
#define _UC_MACHINE_FP(uc) ((uc)->uc_mcontext.__gregs[_REG_A6])
gr[_REG_A6] = frame->f_regs[A6];
frame->f_regs[A6] = gr[_REG_A6];