quoted

It's a somewhat common situation with partially JITed code, if you
don't have an agent. You can still do a lot of useful things.

Like what? How can you say anything about code you don't have?

For example if you combine the PMU topdown measurement, and see if it's
frontend bound, and then you see it has lots of forward conditionals,
then dynamic basic block reordering will help. If you have lots
of cross page jumps then function reordering will help. etc.

quoted

We found it useful to have this extra information during workload
analysis. Forward conditionals and page crossing jumps
are indications of frontend problems.

But you already have the exact same information in {to,from}, why would
you need to repackage information already contained?

Without this patch, we don't know if it's conditional or something else.
And the kernel already knows this for its filtering, so it can as well
report it.

Right the CROSS_* and forward backward information could be computed
later.

-Andi