1 files changed, 10 insertions, 4 deletions
diff --git a/llvm/lib/Analysis/BasicAliasAnalysis.cpp b/llvm/lib/Analysis/BasicAliasAnalysis.cpp
index 58aa670..69e7d25 100644
--- a/llvm/lib/Analysis/BasicAliasAnalysis.cpp
+++ b/llvm/lib/Analysis/BasicAliasAnalysis.cpp
@@ -573,8 +573,15 @@ FunctionModRefBehavior BasicAAResult::getModRefBehavior(ImmutableCallSite CS) {
   if (CS.onlyAccessesArgMemory())
     Min = FunctionModRefBehavior(Min & FMRB_OnlyAccessesArgumentPointees);
 
-  // The AAResultBase base class has some smarts, lets use them.
-  return FunctionModRefBehavior(AAResultBase::getModRefBehavior(CS) & Min);
+  // If CS has operand bundles then aliasing attributes from the function it
+  // calls do not directly apply to the CallSite.  This can be made more
+  // precise in the future.
+  if (!CS.hasOperandBundles())
+    if (const Function *F = CS.getCalledFunction())
+      Min =
+          FunctionModRefBehavior(Min & getBestAAResults().getModRefBehavior(F));
+
+  return Min;
 }
 
 /// Returns the behavior when calling the given function. For use when the call
@@ -593,8 +600,7 @@ FunctionModRefBehavior BasicAAResult::getModRefBehavior(const Function *F) {
   if (F->onlyAccessesArgMemory())
     Min = FunctionModRefBehavior(Min & FMRB_OnlyAccessesArgumentPointees);
 
-  // Otherwise be conservative.
-  return FunctionModRefBehavior(AAResultBase::getModRefBehavior(F) & Min);
+  return Min;
 }
 
 /// Returns true if this is a writeonly (i.e Mod only) parameter.  Currently,