Nope. There's not really any alternative other than "Don't do that", or limit migration to machines that have a superset of the instructions on the original machine.
Usually you configure the VM to only report CPUID values corresponding to lowest-common-denominator features on everything you might want to migrate to. Then as long as the guest code plays nicely and looks at the CPUID feature flags to see what it can use, it'll migrate happily. QEMU has support for this, for instance.
