update comment

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@31023 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/llvm/Target/TargetInstrInfo.h b/include/llvm/Target/TargetInstrInfo.h
index 35be6042e0c6147e60f60b67f1bb6243e4fa2b87..794117058c83a4e1e0c0e63a8839215d7f89fc0c 100644 (file)
--- a/include/llvm/Target/TargetInstrInfo.h
+++ b/include/llvm/Target/TargetInstrInfo.h
@@ -276,9 +276,11 @@ public:
   /// implemented for a target).  Upon success, this returns false and returns
   /// with the following information in various cases:
   ///
-  /// 1. If this block ends with only an unconditional branch, it sets TBB to be
+  /// 1. If this block ends with no branches (it just falls through to its succ)
+  ///    just return false, leaving TBB/FBB null.
+  /// 2. If this block ends with only an unconditional branch, it sets TBB to be
   ///    the destination block.
-  /// 2. If this block ends with an conditional branch, it returns the 'true'
+  /// 3. If this block ends with an conditional branch, it returns the 'true'
   ///    destination in TBB, the 'false' destination in FBB, and a list of
   ///    operands that evaluate the condition.  These operands can be passed to
   ///    other TargetInstrInfo methods to create new branches.