[AliasAnalysis] Take into account readnone attribute for the function arguments

[oota-llvm.git] / lib / Analysis / BasicAliasAnalysis.cpp

diff --git a/lib/Analysis/BasicAliasAnalysis.cpp b/lib/Analysis/BasicAliasAnalysis.cpp
index 26578b83c8b114490f3325f4edef4edd8a6fcf02..1f7e82d315828cf755d31049ddb6ee2306bc7544 100644 (file)
--- a/lib/Analysis/BasicAliasAnalysis.cpp
+++ b/lib/Analysis/BasicAliasAnalysis.cpp
@@ -619,6 +619,9 @@ ModRefInfo BasicAAResult::getArgModRefInfo(ImmutableCallSite CS,
   if (CS.paramHasAttr(ArgIdx + 1, Attribute::ReadOnly))
     return MRI_Ref;
 
+  if (CS.paramHasAttr(ArgIdx + 1, Attribute::ReadNone))
+    return MRI_NoModRef;
+
   return AAResultBase::getArgModRefInfo(CS, ArgIdx);
 }