What happened to the IRA interprocedural reg-alloc work? (function_used_regs and friends)

[Andi Kleen]

Vladimir Makarov <vmakarov@redhat.com> writes:
>>
> As I remember, the performance improvement from this optimization was
> very small.  There were problems in reviewing IRA and I decided to
> simplify this task.
>
> May be it is worth to return to this work.

... especially if you could make it work with LTO.

-Andi