> . Would you be interested in adding a Firefox-based benchmark? As a large
> application it is a good testbed for LTO, FDO and other aggressive
> optimizations.

Sorry about the delayed response. I did notice your mail last week but
I was busy with our conference and then the first couple of days this
week have just disappeared with some internal training.

I would be interested in hearing how you get on with LTO and FDO on
ARM. Listening to Honza talking at the GCC unconference in London
about the memory usage for full LTO with trunk I did wonder what would
happen if we tried it on the ARM target to see what we got, but I
never managed to get around to trying anything there :) . We did look
at getting FDO working with Linaro GCC last cycle but there are still
a couple of issues with PGO in Linaro GCC 4.5.

With respect to LTO , the one problem we have currently is that the
Neon intrinsics aren't streamed out and streamed back in. So you might
have a few issues if your code uses arm_neon.h .
https://bugs.launchpad.net/gcc-linaro/+bug/823548 is an example of
this problem. This was fixed upstream and we probably just need to
backport that into our 4.6 tree. I've tried a backport this morning
and I think I have this right finally.

If you could do a build and a firefox benchmark run in about 30-60
minutes by all means please do let us know how you get on and what you
find. We've been steadily trying to improve the performance of the ARM
toolchain and the biggest improvements you'll notice will be with the
vectorizer but there will be other small improvements that you'll
notice in other general areas of code generation. We would be
interested in feedback about what can be done and to add to our queue
of things to look at and improve for the ARM port of GCC.

With respect to the images, Kiko's probably answered that bit.

cheers
Ramana

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