Add some constantness to BranchProbabilityInfo and BlockFrequnencyInfo.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@146986 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Analysis/BlockFrequencyInfo.cpp

@@ -58,6 +58,6 @@ void BlockFrequencyInfo::print(raw_ostream &O, const Module *) const {
 /// that we should not rely on the value itself, but only on the comparison to
 /// the other block frequencies. We do this to avoid using of floating points.
 ///
-BlockFrequency BlockFrequencyInfo::getBlockFreq(BasicBlock *BB) const {
+BlockFrequency BlockFrequencyInfo::getBlockFreq(const BasicBlock *BB) const {
   return BFI->getBlockFreq(BB);
 }