Re: arm64 pointer tagging, VA-bits, the end of the world...

[Leif Lindholm <leif.lindholm@linaro.org>]

On Wed, Aug 17, 2016 at 06:34:31PM +0100, Peter Maydell wrote:
> On 17 August 2016 at 17:06, Leif Lindholm <leif.lindholm@linaro.org> wrote:
> > And start agitating against pointer tagging in general.
> 
> Why would you want to do that when the architecture has
> specific support for it?

Apart from the situation we find ourselves in, the guarantee that it
will hit us again even within our own architecture, and the certainty
that we will at some point grow beyond the 56-bit limit as well?

No reason.

It would be just about manageable if we had only one architecture to
worry about, but we don't - we have ~3 64-bit ones, or if there was
some sort of industry consortium to ensure alignment - but there
isn't.

Unless someone can think of a way to sneak it into c++17.

/
    Leif