Mark top of managed stack on helper transitions

To assist with unwind from a helper function, store current SP prior
to helper call in Thread.  NOTE: we may wish to push this into a
trampoline to reduce code expansion.  NOTE #2:  Because any helper
function which can throw will be non-leaf, it will spill lr at the saved
address - 4 (the word immediately below caller's Method*).  To identify
the callsite, load the spilled lr, clear the low bit, subtract 2, and use
that address in the native <-> dalvik mapping to identify the callsite.

Also in this CL are a ralloc fix and some extra SSA logging.

Change-Id: Idd442f0c55413a5146c24709b1db1150604f4554
8 files changed
tree: f3f8e9ab69690e729a523188468d7150ede27bf7
  2. build/
  3. src/
  4. test/
  5. tools/