Force-enable coprocessor delayed-sync while creating a save-state. #330
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When making a save state, all the system components are "fast forwarded" to a safe state that can be serialised. If delayedSync (called "Coprocessor Fast Sync" in the UI) is enabled, this works perfectly. If it is disabled, the accurate coprocessor synching interferes with the save-state creation, leading to the game crashing or (worse) the emulator freezing. Star Fox is a good test case - repeatedly saving state and loading it will very quickly cause the game to run super-slowly, hang, or crash. Ideally, somebody should dig into exactly what coprocessor syncing is doing that breaks the assumptions of the state-saving code, but given how complex the whole thing is, and given that it doesn't affect hardware emulation accuracy (real hardware can't save states at all), it's easiest to just force- enable delayedSync while a save-state is in progress. Fix from the jgemu bsnes fork: https://gitlab.com/jgemu/bsnes/-/commit/8b4d1b8ae5b360bbb31aad260da0a160b5a5a758
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When making a save state, all the system components are "fast forwarded" to a safe state that can be serialised. If delayedSync (called "Coprocessor Fast Sync" in the UI) is enabled, this works perfectly. If it is disabled, the accurate coprocessor synching interferes with the save-state creation, leading to the game crashing or (worse) the emulator freezing.
Star Fox is a good test case - repeatedly saving state and loading it will very quickly cause the game to run super-slowly, hang, or crash.
Ideally, somebody should dig into exactly what coprocessor syncing is doing that breaks the assumptions of the state-saving code, but given how complex the whole thing is, and given that it doesn't affect hardware emulation accuracy (real hardware can't save states at all), it's easiest to just force- enable delayedSync while a save-state is in progress.
Fix from the jgemu bsnes fork:
https://gitlab.com/jgemu/bsnes/-/commit/8b4d1b8ae5b360bbb31aad260da0a160b5a5a758