X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FAnalysis%2FAliasAnalysis.cpp;h=c5523ec4634d8e4a83aa33d4afcbb1cf91acf18a;hb=ef4cfc749a61d0d0252196c957697436ba7ec068;hp=369f2f4f90e1e3f30f8d9c22ce11a60ced048068;hpb=d9289a54cdce925fb189c5558f694a241b6e6d04;p=oota-llvm.git

diff --git a/lib/Analysis/AliasAnalysis.cpp b/lib/Analysis/AliasAnalysis.cpp
index 369f2f4f90e..c5523ec4634 100644
--- a/lib/Analysis/AliasAnalysis.cpp
+++ b/lib/Analysis/AliasAnalysis.cpp
@@ -120,9 +120,18 @@ AliasAnalysis::getModRefBehavior(CallSite CS,
 AliasAnalysis::ModRefBehavior
 AliasAnalysis::getModRefBehavior(Function *F,
                                  std::vector<PointerAccessInfo> *Info) {
-  if (F && F->doesNotAccessMemory())
-    // Can't do better than this.
-    return DoesNotAccessMemory;
+  if (F) {
+    if (F->doesNotAccessMemory())
+      // Can't do better than this.
+      return DoesNotAccessMemory;
+    if (F->onlyReadsMemory())
+      return OnlyReadsMemory;
+    if (unsigned id = F->getIntrinsicID()) {
+#define GET_INTRINSIC_MODREF_BEHAVIOR
+#include "llvm/Intrinsics.gen"
+#undef GET_INTRINSIC_MODREF_BEHAVIOR
+    }
+  }
   return UnknownModRefBehavior;
 }
 
@@ -130,10 +139,10 @@ AliasAnalysis::ModRefResult
 AliasAnalysis::getModRefInfo(CallSite CS, Value *P, unsigned Size) {
   ModRefResult Mask = ModRef;
   ModRefBehavior MRB = getModRefBehavior(CS);
-  if (MRB == OnlyReadsMemory)
-    Mask = Ref;
-  else if (MRB == DoesNotAccessMemory)
+  if (MRB == DoesNotAccessMemory)
     return NoModRef;
+  else if (MRB == OnlyReadsMemory)
+    Mask = Ref;
   else if (MRB == AliasAnalysis::AccessesArguments) {
     bool doesAlias = false;
     for (CallSite::arg_iterator AI = CS.arg_begin(), AE = CS.arg_end();
@@ -142,7 +151,7 @@ AliasAnalysis::getModRefInfo(CallSite CS, Value *P, unsigned Size) {
         doesAlias = true;
         break;
       }
-    
+
     if (!doesAlias)
       return NoModRef;
   }