ref: a66be92f63ec59c1811403eb7b95fa72588beee6
dir: /ops.h/
typedef struct Frame Frame; struct Frame { u32int *pc; Frame *next; }; typedef struct Op Op; struct Op { u32int opcode; void (*f)(Frame*,u32int); }; int oplookup(u32int code, void (**f)(Frame*,u32int));