This enables us to handle significantly crazier control flow without
needing to worry about control dependency issues relating to different
groups of insertion points potentially not being control dependent which
can cause incorrect behavior in the optimizer.
Swift SVN r18861
I wish we had the ability to specify a log grouping, so I could log all
of ARC opts or just a specific part of it. Sadly we don't have that now
so I am going to centralize them under the same flag.
Swift SVN r18820
These trap BBs are pattern matched very strictly, i.e. only BBs of the
following form are matched:
bbN:
%_ = builtin_function_ref "int_trap"
apply %_
unreachable
Such BBs can be ignored safely for ARC purposes. This allows us to
handle -O3 code in the ARC optimizer significantly more effectively by
enabling us to handle many more types of check failures.
For instance we can now remove retains, releases in the following code:
bb0:
strong_retain %0
cond_br _, bb1, bb2
bb1:
strong_release %0
...
bb2:
%_ = builtin_function_ref "int_trap"
apply %_
unreachable
rdar://17212610
Swift SVN r18817
Also fixed a small bug related to how we handle arguments. We were not
clearing the state of the argument when we saw a potential decrement of
the argument.
<rdar://problem/17013194>
Swift SVN r18706
GlobalARCSequenceDataflow. Add in the code to implement the bottom up
dataflow, but don't wire it up. Pass in the refactored top down dataflow
to the old pairing pass so we still give correct results.
The next step is to change the pairing analysis to use both the bottom
up and top down dataflow passes.
rdar://16965332
Swift SVN r18551
