REPLAY_WINDOW_SIZE
if (pr->extent < REPLAY_WINDOW_SIZE)
if (delta < REPLAY_WINDOW_SIZE) {
if (pr->extent > REPLAY_WINDOW_SIZE)
pr->extent = REPLAY_WINDOW_SIZE;
pr->extent = REPLAY_WINDOW_SIZE;
#define REPLAY_INDEX(base, i) (((base) + (i)) & (REPLAY_WINDOW_SIZE - 1))
DECLARE_BITMAP(history, REPLAY_WINDOW_SIZE);