About mtune=atom

[Jakub Jelinek]

On Mon, Jan 24, 2011 at 09:25:45AM -0800, John Reiser wrote:
> Actually many of them should be using the new x86_32 software architecture,
> which is the 64-bit instruction set (thus 16 "general" registers, SSE, ...)
> but with integers, longs, and pointers all 32 bits.  The upper 32 bits
> of any user address are 0, and not stored in RAM (except the return address
> of CALL.)  This gives a measurable benefit on boxes with low RAM.

Except that such a model is only barely supported in binutils, the support
for it in gcc is pre-alpha state on a branch and there is no kernel nor
glibc support.

	Jakub