KREG_EIP
gregs->kregs[KREG_EIP] = regs->r_eip;
kregs[KREG_EIP] = label.val[5];
mdb_printf("%%eip = 0x%08p %A\n", kregs[KREG_EIP], kregs[KREG_EIP]);
int got_pc = (gsp->kregs[KREG_EIP] != 0);
uintptr_t pc = gsp->kregs[KREG_EIP];
kregs[KREG_EIP] = pc = fr.fr_savpc;
{ "eip", KREG_EIP, MDB_TGT_R_EXPORT },
#define KREG_PC KREG_EIP