+AliasAnalysis::ModRefBehavior
+TypeBasedAliasAnalysis::getModRefBehavior(ImmutableCallSite CS) {
+ if (!EnableTBAA)
+ return AliasAnalysis::getModRefBehavior(CS);
+
+ ModRefBehavior Min = UnknownModRefBehavior;
+
+ // If this is an "immutable" type, we can assume the call doesn't write
+ // to memory.
+ if (const MDNode *M = CS.getInstruction()->getMetadata(LLVMContext::MD_tbaa))
+ if (TBAANode(M).TypeIsImmutable())
+ Min = OnlyReadsMemory;
+
+ return ModRefBehavior(AliasAnalysis::getModRefBehavior(CS) & Min);
+}
+
+AliasAnalysis::ModRefBehavior
+TypeBasedAliasAnalysis::getModRefBehavior(const Function *F) {
+ // Functions don't have metadata. Just chain to the next implementation.
+ return AliasAnalysis::getModRefBehavior(F);
+}
+