Skip checks on callee which already have norecurse attribute

Author: usha1830

llvm/lib/Transforms/IPO/FunctionAttrs.cpp

@@ -2132,6 +2132,9 @@ static void addNoRecurseAttrs(const SCCNodeSet &SCCNodes,
         if (!Callee || Callee == F)
           return;
 
+        if (Callee->doesNotRecurse())
+          continue;
+
         // External call with NoCallback attribute.
         if (Callee->isDeclaration()) {
           if (Callee->hasFnAttribute(Attribute::NoCallback))