What MCU is it ?
and what is in energy.PowerSave() ; ?
Anyway, if it is AVR based ( like Uno etc.), on waking the sketch starts at exactly after that point in the sketch at which it stopped. So, in your case, on waking, the sketch resumes at the statement after energy.PowerSave() .
Here is a part of schematic.
The J1 is the function button and shared with interrupt pin.
When I press button ,the 328P will always be interrupted.
Can I ignore the external wakeup (INT0) when the CPU wakes up?