Add comments for OrderedInstruction. NFC

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@306201 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 3 insertions, 0 deletions

diff --git a/include/llvm/Transforms/Utils/OrderedInstructions.h b/include/llvm/Transforms/Utils/OrderedInstructions.h
index e043ff39a99..64c6bcb68b1 100644
--- a/include/llvm/Transforms/Utils/OrderedInstructions.h
+++ b/include/llvm/Transforms/Utils/OrderedInstructions.h
@@ -43,6 +43,9 @@ public:
   bool dominates(const Instruction *, const Instruction *) const;
 
   /// Invalidate the OrderedBasicBlock cache when its basic block changes.
+  /// i.e. If an instruction is deleted or added to the basic block, the user
+  /// should call this function to invalidate the OrderedBasicBlock cache for
+  /// this basic block.
   void invalidateBlock(BasicBlock *BB) { OBBMap.erase(BB); }
 };