private static long getEquivalenceKey(DataTypeDB dataTypeDB, DataType dataType) {
		return ((long) System.identityHashCode(dataTypeDB) << 32) +
			(System.identityHashCode(dataType) & 0x0ffffffffL);
	}
Perform forced activation of equivalence cache if not already active. If true
is returned, cache will remain active until {@link #clearEquivalenceCache()}
is invoked.

@return true if successful, false if already active
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/database/data/DataTypeManagerDB.java