epc 134 kernel/exec.c p->trapframe->epc = elf.entry; // initial program counter = main epc 47 kernel/proc.h /* 24 */ uint64 epc; // saved user program counter epc 52 kernel/trap.c p->trapframe->epc = r_sepc(); epc 62 kernel/trap.c p->trapframe->epc += 4; epc 130 kernel/trap.c w_sepc(p->trapframe->epc);