[llvm] r204076 - Use range metadata instead of introducing selects.

[Rafael Espíndola]

> Ok. If we know that the number instructions before coalescing is
> less-or-equal and the spill count is greater in each of the regressions,
> that enough of a clue to pin it on coalescing/scheduling/regalloc.
>
> I don’t like to prevent the right thing at IR level just because downstream
> codegen happens to make bad decisions.

+1

Dan, can you commit it again and open a bug about the codegen issue?

Thanks,
Rafael