Desmume doesn't have dynarec for ARM hardware, so that won't happen.
Dynarec is platform-specific. The Vita uses ARM, so there needs to be a dynarec specifically for the ARM platform. The DS is actually ARM anyway, but presumably the instructions aren't all natively compatible.
Dynarec is platform-specific. The Vita uses ARM, so there needs to be a dynarec specifically for the ARM platform. The DS is actually ARM anyway, but presumably the instructions aren't all natively compatible.