Add argmemonly attribute.

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

diff --git a/lib/Analysis/BasicAliasAnalysis.cpp b/lib/Analysis/BasicAliasAnalysis.cpp
index 8e812252fdfea85c1498706c3356e7957f114432..68f766edb301342eedc8c2f23910bdbf6e2db8d0 100644 (file)
--- a/lib/Analysis/BasicAliasAnalysis.cpp
+++ b/lib/Analysis/BasicAliasAnalysis.cpp
@@ -685,6 +685,9 @@ BasicAliasAnalysis::getModRefBehavior(ImmutableCallSite CS) {
   if (CS.onlyReadsMemory())
     Min = OnlyReadsMemory;
 
+  if (CS.onlyAccessesArgMemory())
+    Min = ModRefBehavior(Min & OnlyAccessesArgumentPointees);
+
   // The AliasAnalysis base class has some smarts, lets use them.
   return ModRefBehavior(AliasAnalysis::getModRefBehavior(CS) & Min);
 }
@@ -710,6 +713,9 @@ BasicAliasAnalysis::getModRefBehavior(const Function *F) {
   if (F->onlyReadsMemory())
     Min = OnlyReadsMemory;
 
+  if (F->onlyAccessesArgMemory())
+    Min = ModRefBehavior(Min & OnlyAccessesArgumentPointees);
+
   const TargetLibraryInfo &TLI =
       getAnalysis<TargetLibraryInfoWrapperPass>().getTLI();
   if (isMemsetPattern16(F, TLI))