In particular create Keeps for mode_T nodes in one go instead of adding one Proj to the Keep after another.

The only user should be an arch_add_irn_flags() instead.
It was harmless though, because no other flags were set.

Rematerialisations involving multiple nodes and Projs (e.g. Proj->Load) got miscounted.
Now a rematerialization always counts as 1.

The node was just created, so it is not scheduled.

Move the values interfere function to belive.h, move the inline
implementation into belive.c

- Remove value_dominates_intrablock()/value_strictly_dominates_intrablock()
  and use sched_comes_before() instead
- Use bool instead of int return types.
- Assert that we don't check if a node interferes with itself as that is
  nearly always a bug in the code.

- the linked lists are introduced to get a deterministic order
- irnodehashmap instead of set should be slightly faster

It has been empty for nearly all systems. People who used to put stuff
in config.h can still create a config.h on their own and inject
-include (gcc) or /FI (msvc) into their CPPFLAGS.

Just state the copyright and the project the files belong to. You can
then find the COPYING file for the whole project.

cleanup: Remove pointless assert(is_${NODE}(x)) just before get_${NODE}_${FOO}(x), which do the same assert.

That way the spill engine can rematerialize the loads and needs no
extra spills for these values.

The reloader never is a block.

bespillutil: Inline be_add_reload2() into its only caller be_add_reload(), which in turn only calls the former.