Add more constantness in BlockFrequencyInfo.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@136816 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/BlockFrequencyInfo.cpp b/lib/Analysis/BlockFrequencyInfo.cpp
index 5bb3540..ee89915 100644
--- a/lib/Analysis/BlockFrequencyInfo.cpp
+++ b/lib/Analysis/BlockFrequencyInfo.cpp
@@ -54,6 +54,6 @@
 /// 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) {
+BlockFrequency BlockFrequencyInfo::getBlockFreq(BasicBlock *BB) const {
   return BFI->getBlockFreq(BB);
 }