FDO and LTO on ARM

[Mike Hommey]

On Fri, Aug 05, 2011 at 09:32:05AM +0200, Richard Guenther wrote:
> Well, but unless your training coverage is 100% all parts with no coverage
> get optimized with -O3 instead of -Os.  And I bet coverage for mozilla
> isn't even close to 100%.  Thus I think recommending -O3 for FDO is
> usually a bad idea.

Experience shows that this isn't true.

> So - did you try FDO with -O2? ;)

Leads to roughly the same as -O3+FDO. The apk is also the same size, as
well as individual libraries.

Mike