Allow clients to be more efficient.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12831 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Analysis/BasicAliasAnalysis.cpp

@@ -49,6 +49,10 @@ namespace {
 
     ModRefResult getModRefInfo(CallSite CS, Value *P, unsigned Size);
 
+    /// hasNoModRefInfoForCalls - We have no way to test one call against
+    /// another, unless they are pure or const.
+    virtual bool hasNoModRefInfoForCalls() const { return true; }
+
     /// pointsToConstantMemory - Chase pointers until we find a (constant
     /// global) or not.
     bool pointsToConstantMemory(const Value *P);