add tail marker as a comment


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@21739 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/CBackend/CBackend.cpp b/lib/Target/CBackend/CBackend.cpp
index 2cd5644..be124b0 100644
--- a/lib/Target/CBackend/CBackend.cpp
+++ b/lib/Target/CBackend/CBackend.cpp
@@ -1542,6 +1542,7 @@
   // match exactly.
   //
   bool WroteCallee = false;
+  if (I.isTailCall()) Out << " /*tail*/ ";
   if (ConstantExpr *CE = dyn_cast<ConstantExpr>(Callee))
     if (CE->getOpcode() == Instruction::Cast)
       if (Function *RF = dyn_cast<Function>(CE->getOperand(0))) {