This commit fixes a bunch of problems I found in TBAA. Some fun
examples:
1. We were not handling protocols correctly.
2. We were not handling enums correctly.
3. We were not handling builtins correctly all the time.
...
And much more.
I also added a fairly exhaustive test.
Additionally I checked the benchmarks and did not see any regressions.
rdar://16651852
Swift SVN r18148
The reason that this is important is that we *ARE* allowing the stdlib
to perform certain types of type punning for efficiency implying we need
to have a type oracle instruction to have safety.
A type oracle instruction is an instruction which implies undefined behavior
unless its operand/result is of a certain type (allowing us to ignore that
possibility).
In a following commit I am going to go over and fix any problems in the
actual TBAA implementation and give all the various checks tests.
rdar://16651852
Swift SVN r18090
This is due to MayHaveSideEffects encompassing ref count effects and a
myriad of other effects. If/when we separate the two concepts (which is
cleaner IMHO), the flag will no longer be necessary.
Swift SVN r16807
