Tail merging pass shall not break up IT blocks. rdar://8115404


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106517 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/TargetInstrInfoImpl.cpp b/lib/CodeGen/TargetInstrInfoImpl.cpp
index 53f3ee8..5e145cf 100644
--- a/lib/CodeGen/TargetInstrInfoImpl.cpp
+++ b/lib/CodeGen/TargetInstrInfoImpl.cpp
@@ -28,6 +28,8 @@
 #include "llvm/Support/raw_ostream.h"
 using namespace llvm;
 
+/// ReplaceTailWithBranchTo - Delete the instruction OldInst and everything
+/// after it, replacing it with an unconditional branch to NewDest.
 void
 TargetInstrInfoImpl::ReplaceTailWithBranchTo(MachineBasicBlock::iterator Tail,
                                              MachineBasicBlock *NewDest) const {