swift234

Debug Info: Don't emit dbg.declares for SIL-optimized code.
A dbg.declare is only meaningful if there is a single alloca for
the variable that is live throughout the function. With SIL
optimizations this is not guranteed and a variable can end up in
two allocas (for example, one function inlined twice).

Caught by an assertion in LLVM.

rdar://problem/21109015

Swift SVN r29186