diff --git a/include/llvm/Analysis/BlockFrequencyInfo.h b/include/llvm/Analysis/BlockFrequencyInfo.h
index bd9807dc896..5978d5fa0ee 100644
--- a/include/llvm/Analysis/BlockFrequencyInfo.h
+++ b/include/llvm/Analysis/BlockFrequencyInfo.h
@@ -46,7 +46,7 @@ public:
   /// 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 getBlockFreq(BasicBlock *BB);
+  BlockFrequency getBlockFreq(BasicBlock *BB) const;
 };
 
 }
diff --git a/include/llvm/CodeGen/MachineBlockFrequencyInfo.h b/include/llvm/CodeGen/MachineBlockFrequencyInfo.h
index 63ab2ef850b..416d40bf309 100644
--- a/include/llvm/CodeGen/MachineBlockFrequencyInfo.h
+++ b/include/llvm/CodeGen/MachineBlockFrequencyInfo.h
@@ -46,7 +46,7 @@ public:
   /// 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 getBlockFreq(MachineBasicBlock *MBB);
+  BlockFrequency getBlockFreq(MachineBasicBlock *MBB) const;
 };
 
 }
diff --git a/lib/Analysis/BlockFrequencyInfo.cpp b/lib/Analysis/BlockFrequencyInfo.cpp
index 5bb3540a1ff..ee899153e1d 100644
--- a/lib/Analysis/BlockFrequencyInfo.cpp
+++ b/lib/Analysis/BlockFrequencyInfo.cpp
@@ -54,6 +54,6 @@ bool BlockFrequencyInfo::runOnFunction(Function &F) {
 /// 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);
 }
diff --git a/lib/CodeGen/MachineBlockFrequencyInfo.cpp b/lib/CodeGen/MachineBlockFrequencyInfo.cpp
index 4e08ebe6a94..b92cda96147 100644
--- a/lib/CodeGen/MachineBlockFrequencyInfo.cpp
+++ b/lib/CodeGen/MachineBlockFrequencyInfo.cpp
@@ -55,6 +55,7 @@ bool MachineBlockFrequencyInfo::runOnMachineFunction(MachineFunction &F) {
 /// 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 MachineBlockFrequencyInfo::getBlockFreq(MachineBasicBlock *MBB) {
+BlockFrequency MachineBlockFrequencyInfo::
+getBlockFreq(MachineBasicBlock *MBB) const {
   return MBFI->getBlockFreq(MBB);
 }