Turn down the BDD zip limit a little tiny bit, to get memory
consumption down a little bit and avoid the OOM killer.
Yet more timeout checks.
Merge github.com:sos22/SLI
Merge github.com:sos22/SLI
Further tweak to avail analysis.  Sometimes it manages to show that a
particular path is completely unreachable.  Take advantage of that.
Fix the NO_STATIC_ALIASING build.
Add a slightly easier stats collector thing.
More timeout checks.
Rejigger things so that we no longer need to do an ifelse() just
because the variable order might have changed a bit, but instead fix
things up from makeInternal().
Take advantage of newly-flexible node() interface in a couple of places.
Yet more timeout fixes.
The BDD memo tables contain only weak references and tend to be quite
large.  Arrange that they can trigger a GC sweep when they get too
big.
availExpressionAnalysis() can sometimes allocate very large amounts of
memory very quickly, which can trigger an OOM kill, which is annoying,
because it can be safely stopped and restarted.  Arrange for it to
notice that it's using too much memory and get out early when
appropriate.
Let the BDD intern table grow a bit further before forcing a GC.
LibVEX_want_GC() is (a) very small and (b) very frequently called, so
allow it to be inlined.
Whoops: cond != cond' && t != t' && f != f' is not enough to show
that node(cond, t, f) != node(cond', t', f'), because of the variable
reordering rules.  Stop assuming that it is.
The previous fix means that we test want_gc less often, so need to set
it a bit more aggressively.  Do so.
YATimeout fix.
Further work on early-out from alias analysis.
Debug mode for localiseLoads.