To determine whether it is safe to duplicate the instruction by duplicating the
loop body. Will be used in loop versioning for array and loop unrolling.
The two changes were:
1. I added a graphtraits implementation for a const
DomTreeNodeBase<SILBasicBlock>.
2. LoopInfoBase::Analyze() => LoopInfoBase::analyze().
Swift SVN r31807
This follows the model of dominance info and allows me to create reachability
methods on SILBasicBlock without creating dependencies from swiftSIL to
swiftSILAnalysis.
Swift SVN r21866