Greetings! It just occurred to me that message port handles being addresses are always on even numbers due to alignment constraints. After looking at Gunnar von Boehn's additions to the 68080 and SAGA softcores, it occurred to me that using bit zero as a flag could be used to switch to a different message port encoding such as an enumeration. Once that is no longer address constrained, it could allow 64-bit addressing both on AmigaOS 3+ and ApolloOS. If MorphOS follows suit, great!
What was the problem you try to solve with 64-bit messageports? This sounds like a solution looking for a problem.
Using some bits of addresses for "magic" information is asking for trouble. Just ask how easy it's to run AmigaBASIC on Amigas with 32-bit memory. Or how convenient it is that AllocEntry() uses bit 31 to indicate error condition.
Also, this isn't a generic solution to encode 64-bit addresses as many addresses can be odd.
If you go 64-bit do it properly with real 64-bit addressing everywhere. 32-bit legacy stuff can be run in a runtime environment.
