On Mon, 7 May 2018 15:54:01 +0000, Wayne Driscoll 
<[email protected]> wrote:

> Yes, the high bit convention has to change for
> interfaces that accept 64 bit addresses. The issue
> is that in order to change the convention for 32
> bit programs, either 1 -  an additional AMODE
> would need to be supported by the hardware,

I don't know why you think an additional AMODE
would help at all.

> or 2 - EVERY existing program would have to be
> redesigned and retested in order to follow a new
> convention.

Yes, I believe we should START this process by
allowing for 32-bit addressing. With a goal of
only having software that runs AM64 - regardless
of whether it is a 32-bit or 64-bit program.

> The limited benefit of allowing for an extra 2GiB
> of virtual storage to an address space that can,
> using 64 bit addressing, already support 16
> exabytes - 2GiB seems like a massive waste of
> resources.

If high-level language compilers start following
the 32-bit addressing rules, they will naturally
start supporting 4 GiB with no additional
effort by the programmer.

BFN. Paul.

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