Reenable tail calls for iOS 5.0 and later.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141370 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/ARM/ARMISelLowering.cpp b/lib/Target/ARM/ARMISelLowering.cpp
index c352b46..6386c4d 100644
--- a/lib/Target/ARM/ARMISelLowering.cpp
+++ b/lib/Target/ARM/ARMISelLowering.cpp
@@ -1222,8 +1222,8 @@
   MachineFunction &MF = DAG.getMachineFunction();
   bool IsStructRet    = (Outs.empty()) ? false : Outs[0].Flags.isSRet();
   bool IsSibCall = false;
-  // Temporarily disable tail calls so things don't break.
-  if (!EnableARMTailCalls)
+  // Disable tail calls if they're not supported.
+  if (!EnableARMTailCalls && !Subtarget->supportsTailCall())
     isTailCall = false;
   if (isTailCall) {
     // Check if it's really possible to do a tail call.