[llvm] r193393 - Optimize concat_vectors(X, undef) -> scalar_to_vector(X).

[Hans Wennborg]

Hi Nadav,

On Thu, Oct 24, 2013 at 11:41 PM, Nadav Rotem <nrotem at apple.com> wrote:
> Author: nadav
> Date: Fri Oct 25 01:41:18 2013
> New Revision: 193393
>
> URL: http://llvm.org/viewvc/llvm-project?rev=193393&view=rev
> Log:
> Optimize concat_vectors(X, undef) -> scalar_to_vector(X).
> This optimization is not SSE specific so I am moving it to DAGco.
> The new scalar_to_vector dag node exposed a missing pattern in the AArch64 target that I needed to add.

This seems to have caused PR18162. This breaks the Chromium build.

Sorry for noticing this so late after the code was committed; we
didn't have code that tickles this case until recently.

Can you take a look?

Thanks,
Hans