PN_SAVED_REGS     127 core/callcc.c    cc = PN_ALLOC_N(PN_TCONT, struct PNCont, sizeof(PN) * (n + 3 + PN_SAVED_REGS));
PN_SAVED_REGS     152 core/callcc.c      PN *d = cc->stack + 4 + PN_SAVED_REGS;
PN_SAVED_REGS     158 core/callcc.c    PN_MEMCPY_N((char *)(cc->stack + 4 + PN_SAVED_REGS), start + 1, PN, n - 1);