In some rare instances, class objects can be freed before the last
instance of that class, causing a problem in the sweep phase where
we look at the class of the object being freed.

So we keep unreachable classes around for an extra collection to be
safe.

This reverts commit e0bd51eb.

jemalloc

some misc microoptimizations

Yes they exist, for example "try getting this attribute
and if it exists call it, otherwise do something else".
Probably not a huge perf improvement since the
exception-throwing will probably dominate.

Use the same "only do this for immortal strings" trick to get
around gc issues.

Only do this for calls with immortally-interned strings so that
we can side-step the track-gc-references-in-ics issue for now.

type speculation support

I have a whole bunch of mechanical changes to allow speculation, but
I think our pre-existing speculation rules end up hurting the macrobenchmarks.
I'd like to get those in and then separately work on making in beneficial.

It'll break once we add frame introspection info to it, but
for now it just needed some massaging.

Currently it gets somewhat hidden by the object-caching behavior.
Add an API for fetching it out, and use it to make the "prettified"
IR (which you see on -vv or higher) include the slowpath addresses.

Using NULL for undefined values is confusing since maybe
something actually returned that.  So try using -1.

Somewhat ad-hoc at the moment; only added for a few types
of operations.

Add a couple tests to the travis-ci configuration

correct output filenames for the new .so's

- Build and run in Debug mode (but not the extra tests)
- make sure that building + running doesn't dirty the repository.

fix null check

add support for the _curses, bz2, and grp modules (mercurial needs them)

don't do isNonheapRoot first, since .so's loading at arbitrary accesses can put max/min on either side of our gc heap.

add long.__float__ attribute

Revert "Merge pull request #685 from undingen/interp_gc2"

This reverts commit 78493220, reversing
changes made to 194d51eb.

This was a merge conflict between #656 and #693

Fix lea

baseline jit: directly emit patchpoints instead of using runtime ICs

Don't guard types sometimes

I encountered this issue sometimes with the protobuf integration test.

this also adds support for calling 8 arg functions (=2 stack args)