Previously, BranchProbabilityInfo::calcLoopBranchHeuristics would determine the weights of basic blocks inside loops even when it didn't have enough information to estimate the branch probabilities correctly. This patch fixes the function to exit early if it doesn't see any exit edges or back edges and let the later heuristics determine the weights.
This fixes PR18705 and <rdar://problem/15991090>.
Differential Revision: http://reviews.llvm.org/D3363
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206194 91177308-0d34-0410-b5e6-96231b3b80d8
Fix a bug triggered in IfConverterTriangle when CvtBB has multiple predecessors
by getting the weights before removing a successor.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200958 91177308-0d34-0410-b5e6-96231b3b80d8
