[jit] Merger of trunk r215803 into jit branch

[David Malcolm]

I've merged the last ~3 weeks of changes of svn trunk to the git branch
dmalcolm/jit, pushing it as
dbfbacdbbf727e8ab3a8cff2d5650d8000de0449.

Specifically, this is from trunk r215803 aka
68874c5d021dd6b8b740ffd23960e46e333270b5 (2014-10-02) bringing in all
changes since r215090 aka    65d8ffc239855f020a53c9ca5309642fec98ce9a
(2014-09-09).
    
With this I see jit.sum has: # of expected passes 4663 and no failures.