X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FAnalysis%2FBasicAliasAnalysis.cpp;h=fe71f04098b13061a0b04c4dcf2a99bc3fd7f9dd;hb=ef4cfc749a61d0d0252196c957697436ba7ec068;hp=1002868e84cbb72240ef4f6419eec13a1e39ea24;hpb=3311a1f8f0d8a2c6d940802bbb95eba0b801a615;p=oota-llvm.git

diff --git a/lib/Analysis/BasicAliasAnalysis.cpp b/lib/Analysis/BasicAliasAnalysis.cpp
index 1002868e84c..fe71f04098b 100644
--- a/lib/Analysis/BasicAliasAnalysis.cpp
+++ b/lib/Analysis/BasicAliasAnalysis.cpp
@@ -64,30 +64,6 @@ static const Value *GetGEPOperands(const Value *V,
   return V;
 }
 
-/// isNoAliasCall - Return true if this pointer is returned by a noalias
-/// function.
-static bool isNoAliasCall(const Value *V) {
-  if (isa<CallInst>(V) || isa<InvokeInst>(V))
-    return CallSite(const_cast<Instruction*>(cast<Instruction>(V)))
-      .paramHasAttr(0, Attribute::NoAlias);
-  return false;
-}
-
-/// isIdentifiedObject - Return true if this pointer refers to a distinct and
-/// identifiable object.  This returns true for:
-///    Global Variables and Functions
-///    Allocas and Mallocs
-///    ByVal and NoAlias Arguments
-///    NoAlias returns
-///
-bool llvm::isIdentifiedObject(const Value *V) {
-  if (isa<GlobalValue>(V) || isa<AllocationInst>(V) || isNoAliasCall(V))
-    return true;
-  if (const Argument *A = dyn_cast<Argument>(V))
-    return A->hasNoAliasAttr() || A->hasByValAttr();
-  return false;
-}
-
 /// isKnownNonNull - Return true if we know that the specified value is never
 /// null.
 static bool isKnownNonNull(const Value *V) {
@@ -179,11 +155,6 @@ namespace {
       return MayAlias;
     }
 
-    virtual ModRefBehavior getModRefBehavior(Function *F, CallSite CS,
-                                         std::vector<PointerAccessInfo> *Info) {
-      return UnknownModRefBehavior;
-    }
-
     virtual void getArgumentAccesses(Function *F, CallSite CS,
                                      std::vector<PointerAccessInfo> &Info) {
       assert(0 && "This method may not be called on this function!");
@@ -230,7 +201,7 @@ namespace {
 
     ModRefResult getModRefInfo(CallSite CS, Value *P, unsigned Size);
     ModRefResult getModRefInfo(CallSite CS1, CallSite CS2);
-    
+
     /// hasNoModRefInfoForCalls - We can provide mod/ref information against
     /// non-escaping allocations.
     virtual bool hasNoModRefInfoForCalls() const { return false; }
@@ -273,6 +244,7 @@ bool BasicAliasAnalysis::pointsToConstantMemory(const Value *P) {
   return false;
 }
 
+
 // getModRefInfo - Check to see if the specified callsite can clobber the
 // specified memory object.  Since we only look at local properties of this
 // function, we really can't say much about this query.  We do, however, use
@@ -296,7 +268,7 @@ BasicAliasAnalysis::getModRefInfo(CallSite CS, Value *P, unsigned Size) {
     // If the pointer is to a locally allocated object that does not escape,
     // then the call can not mod/ref the pointer unless the call takes the
     // argument without capturing it.
-    if (isNonEscapingLocalObject(Object)) {
+    if (isNonEscapingLocalObject(Object) && CS.getInstruction() != Object) {
       bool passedAsArg = false;
       // TODO: Eventually only check 'nocapture' arguments.
       for (CallSite::arg_iterator CI = CS.arg_begin(), CE = CS.arg_end();
@@ -391,10 +363,10 @@ BasicAliasAnalysis::alias(const Value *V1, unsigned V1Size,
   // non-escaping local object, then we know the object couldn't escape to a
   // point where the call could return it.
   if ((isa<CallInst>(O1) || isa<InvokeInst>(O1)) &&
-      isNonEscapingLocalObject(O2))
+      isNonEscapingLocalObject(O2) && O1 != O2)
     return NoAlias;
   if ((isa<CallInst>(O2) || isa<InvokeInst>(O2)) &&
-      isNonEscapingLocalObject(O1))
+      isNonEscapingLocalObject(O1) && O1 != O2)
     return NoAlias;
   
   // If we have two gep instructions with must-alias'ing base pointers, figure