On Tue, Jul 23, 2019 at 07:52:09AM -0700, Andrew Lutomirski wrote:
Things like CMPXCHG16B that change the set of things that can be done
on
the CPU. I could easily imagine programs that use algorithms that
fundamentally depend on CMPXCHG16B. There is no drop-in replacement.
FWIW, CMPXCH16B is a hard requirement for Windows 8.1 (August 2013!) and
beyond.
In AMD-land, it seems that CMPXCHG16B support was added at the same time
as they added SSE3 (ie April 2005). so requiring that would cut off the
1st-gen single-core x86_64 AMD parts)
All non-AMD x86_64 parts support both CMPXCHG16B and SSE3.
- Solomon
--
Solomon Peachy pizza at shaftnet dot org
High Springs, FL ^^ (email/xmpp) ^^
Quidquid latine dictum sit, altum videtur.