Move Value::getUnderlyingObject to be a standalone

function so that it can live in Analysis instead of
VMCore.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121885 91177308-0d34-0410-b5e6-96231b3b80d8

9 files changed, 44 insertions, 20 deletions

diff --git a/lib/Analysis/BasicAliasAnalysis.cpp b/lib/Analysis/BasicAliasAnalysis.cpp
index 17a502e..fc996fb 100644
--- a/lib/Analysis/BasicAliasAnalysis.cpp
+++ b/lib/Analysis/BasicAliasAnalysis.cpp
@@ -233,7 +233,7 @@ static Value *GetLinearExpression(Value *V, APInt &Scale, APInt &Offset,
 /// the gep cannot necessarily be reconstructed from its decomposed form.
 ///
 /// When TargetData is around, this function is capable of analyzing everything
-/// that Value::getUnderlyingObject() can look through.  When not, it just looks
+/// that GetUnderlyingObject can look through.  When not, it just looks
 /// through pointer casts.
 ///
 static const Value *
@@ -528,7 +528,7 @@ BasicAliasAnalysis::pointsToConstantMemory(const Location &Loc, bool OrLocal) {
   SmallVector<const Value *, 16> Worklist;
   Worklist.push_back(Loc.Ptr);
   do {
-    const Value *V = Worklist.pop_back_val()->getUnderlyingObject();
+    const Value *V = GetUnderlyingObject(Worklist.pop_back_val());
     if (!Visited.insert(V)) {
       Visited.clear();
       return AliasAnalysis::pointsToConstantMemory(Loc, OrLocal);
@@ -633,7 +633,7 @@ BasicAliasAnalysis::getModRefInfo(ImmutableCallSite CS,
   assert(notDifferentParent(CS.getInstruction(), Loc.Ptr) &&
          "AliasAnalysis query involving multiple functions!");
 
-  const Value *Object = Loc.Ptr->getUnderlyingObject();
+  const Value *Object = GetUnderlyingObject(Loc.Ptr);
   
   // If this is a tail call and Loc.Ptr points to a stack location, we know that
   // the tail call cannot access or modify the local stack.
@@ -761,7 +761,7 @@ BasicAliasAnalysis::getModRefInfo(ImmutableCallSite CS,
 
 /// aliasGEP - Provide a bunch of ad-hoc rules to disambiguate a GEP instruction
 /// against another pointer.  We know that V1 is a GEP, but we don't know
-/// anything about V2.  UnderlyingV1 is GEP1->getUnderlyingObject(),
+/// anything about V2.  UnderlyingV1 is GetUnderlyingObject(GEP1),
 /// UnderlyingV2 is the same for V2.
 ///
 AliasAnalysis::AliasResult
@@ -807,7 +807,7 @@ BasicAliasAnalysis::aliasGEP(const GEPOperator *GEP1, uint64_t V1Size,
     // to handle without it.
     if (GEP1BasePtr != UnderlyingV1 || GEP2BasePtr != UnderlyingV2) {
       assert(TD == 0 &&
-             "DecomposeGEPExpression and getUnderlyingObject disagree!");
+             "DecomposeGEPExpression and GetUnderlyingObject disagree!");
       return MayAlias;
     }
     
@@ -843,7 +843,7 @@ BasicAliasAnalysis::aliasGEP(const GEPOperator *GEP1, uint64_t V1Size,
     // to handle without it.
     if (GEP1BasePtr != UnderlyingV1) {
       assert(TD == 0 &&
-             "DecomposeGEPExpression and getUnderlyingObject disagree!");
+             "DecomposeGEPExpression and GetUnderlyingObject disagree!");
       return MayAlias;
     }
   }
@@ -1044,8 +1044,8 @@ BasicAliasAnalysis::aliasCheck(const Value *V1, uint64_t V1Size,
     return NoAlias;  // Scalars cannot alias each other
 
   // Figure out what objects these things are pointing to if we can.
-  const Value *O1 = V1->getUnderlyingObject();
-  const Value *O2 = V2->getUnderlyingObject();
+  const Value *O1 = GetUnderlyingObject(V1);
+  const Value *O2 = GetUnderlyingObject(V2);
 
   // Null values in the default address space don't point to any object, so they
   // don't alias any other pointer.
diff --git a/lib/Analysis/ConstantFolding.cpp b/lib/Analysis/ConstantFolding.cpp
index 68a55b6..73ee5cd 100644
--- a/lib/Analysis/ConstantFolding.cpp
+++ b/lib/Analysis/ConstantFolding.cpp
@@ -467,7 +467,7 @@ Constant *llvm::ConstantFoldLoadFromConstPtr(Constant *C,
   
   // If this load comes from anywhere in a constant global, and if the global
   // is all undef or zero, we know what it loads.
-  if (GlobalVariable *GV = dyn_cast<GlobalVariable>(CE->getUnderlyingObject())){
+  if (GlobalVariable *GV = dyn_cast<GlobalVariable>(GetUnderlyingObject(CE))){
     if (GV->isConstant() && GV->hasDefinitiveInitializer()) {
       const Type *ResTy = cast<PointerType>(C->getType())->getElementType();
       if (GV->getInitializer()->isNullValue())
diff --git a/lib/Analysis/IPA/GlobalsModRef.cpp b/lib/Analysis/IPA/GlobalsModRef.cpp
index 456a80a..c18dc47 100644
--- a/lib/Analysis/IPA/GlobalsModRef.cpp
+++ b/lib/Analysis/IPA/GlobalsModRef.cpp
@@ -24,6 +24,7 @@
 #include "llvm/Analysis/AliasAnalysis.h"
 #include "llvm/Analysis/CallGraph.h"
 #include "llvm/Analysis/MemoryBuiltins.h"
+#include "llvm/Analysis/ValueTracking.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/InstIterator.h"
 #include "llvm/ADT/Statistic.h"
@@ -324,7 +325,7 @@ bool GlobalsModRef::AnalyzeIndirectGlobalMemory(GlobalValue *GV) {
         continue;
 
       // Check the value being stored.
-      Value *Ptr = SI->getOperand(0)->getUnderlyingObject();
+      Value *Ptr = GetUnderlyingObject(SI->getOperand(0));
 
       if (isMalloc(Ptr)) {
         // Okay, easy case.
@@ -489,8 +490,8 @@ AliasAnalysis::AliasResult
 GlobalsModRef::alias(const Location &LocA,
                      const Location &LocB) {
   // Get the base object these pointers point to.
-  const Value *UV1 = LocA.Ptr->getUnderlyingObject();
-  const Value *UV2 = LocB.Ptr->getUnderlyingObject();
+  const Value *UV1 = GetUnderlyingObject(LocA.Ptr);
+  const Value *UV2 = GetUnderlyingObject(LocB.Ptr);
 
   // If either of the underlying values is a global, they may be non-addr-taken
   // globals, which we can answer queries about.
@@ -549,7 +550,7 @@ GlobalsModRef::getModRefInfo(ImmutableCallSite CS,
   // If we are asking for mod/ref info of a direct call with a pointer to a
   // global we are tracking, return information if we have it.
   if (const GlobalValue *GV =
-        dyn_cast<GlobalValue>(Loc.Ptr->getUnderlyingObject()))
+        dyn_cast<GlobalValue>(GetUnderlyingObject(Loc.Ptr)))
     if (GV->hasLocalLinkage())
       if (const Function *F = CS.getCalledFunction())
         if (NonAddressTakenGlobals.count(GV))
diff --git a/lib/Analysis/LazyValueInfo.cpp b/lib/Analysis/LazyValueInfo.cpp
index d73c504..eab4ca0 100644
--- a/lib/Analysis/LazyValueInfo.cpp
+++ b/lib/Analysis/LazyValueInfo.cpp
@@ -14,6 +14,7 @@
 
 #define DEBUG_TYPE "lazy-value-info"
 #include "llvm/Analysis/LazyValueInfo.h"
+#include "llvm/Analysis/ValueTracking.h"
 #include "llvm/Constants.h"
 #include "llvm/Instructions.h"
 #include "llvm/Analysis/ConstantFolding.h"
@@ -414,8 +415,8 @@ LVILatticeVal LazyValueInfoCache::getBlockValue(Value *Val, BasicBlock *BB) {
       for (BasicBlock::iterator BI = BB->begin(), BE = BB->end();BI != BE;++BI){
         LoadInst *L = dyn_cast<LoadInst>(BI);
         if (L && L->getPointerAddressSpace() == 0 &&
-            L->getPointerOperand()->getUnderlyingObject() ==
-              Val->getUnderlyingObject()) {
+            GetUnderlyingObject(L->getPointerOperand()) ==
+              GetUnderlyingObject(Val)) {
           NotNull = true;
           break;
         }
diff --git a/lib/Analysis/Lint.cpp b/lib/Analysis/Lint.cpp
index 72ae7ab..d68fcd2 100644
--- a/lib/Analysis/Lint.cpp
+++ b/lib/Analysis/Lint.cpp
@@ -567,7 +567,7 @@ Value *Lint::findValueImpl(Value *V, bool OffsetOk,
   // TODO: Look through eliminable cast pairs.
   // TODO: Look through calls with unique return values.
   // TODO: Look through vector insert/extract/shuffle.
-  V = OffsetOk ? V->getUnderlyingObject() : V->stripPointerCasts();
+  V = OffsetOk ? GetUnderlyingObject(V) : V->stripPointerCasts();
   if (LoadInst *L = dyn_cast<LoadInst>(V)) {
     BasicBlock::iterator BBI = L;
     BasicBlock *BB = L->getParent();
diff --git a/lib/Analysis/Loads.cpp b/lib/Analysis/Loads.cpp
index b1f2cb4..2ea27fb 100644
--- a/lib/Analysis/Loads.cpp
+++ b/lib/Analysis/Loads.cpp
@@ -49,7 +49,7 @@ static bool AreEquivalentAddressValues(const Value *A, const Value *B) {
 /// getUnderlyingObjectWithOffset - Strip off up to MaxLookup GEPs and
 /// bitcasts to get back to the underlying object being addressed, keeping
 /// track of the offset in bytes from the GEPs relative to the result.
-/// This is closely related to Value::getUnderlyingObject but is located
+/// This is closely related to GetUnderlyingObject but is located
 /// here to avoid making VMCore depend on TargetData.
 static Value *getUnderlyingObjectWithOffset(Value *V, const TargetData *TD,
                                             uint64_t &ByteOffset,
diff --git a/lib/Analysis/LoopDependenceAnalysis.cpp b/lib/Analysis/LoopDependenceAnalysis.cpp
index 618c987..88fc7ed 100644
--- a/lib/Analysis/LoopDependenceAnalysis.cpp
+++ b/lib/Analysis/LoopDependenceAnalysis.cpp
@@ -27,6 +27,7 @@
 #include "llvm/Analysis/LoopPass.h"
 #include "llvm/Analysis/ScalarEvolution.h"
 #include "llvm/Analysis/ScalarEvolutionExpressions.h"
+#include "llvm/Analysis/ValueTracking.h"
 #include "llvm/Instructions.h"
 #include "llvm/Operator.h"
 #include "llvm/Support/Allocator.h"
@@ -90,8 +91,8 @@ static Value *GetPointerOperand(Value *I) {
 static AliasAnalysis::AliasResult UnderlyingObjectsAlias(AliasAnalysis *AA,
                                                          const Value *A,
                                                          const Value *B) {
-  const Value *aObj = A->getUnderlyingObject();
-  const Value *bObj = B->getUnderlyingObject();
+  const Value *aObj = GetUnderlyingObject(A);
+  const Value *bObj = GetUnderlyingObject(B);
   return AA->alias(aObj, AA->getTypeStoreSize(aObj->getType()),
                    bObj, AA->getTypeStoreSize(bObj->getType()));
 }
diff --git a/lib/Analysis/MemoryDependenceAnalysis.cpp b/lib/Analysis/MemoryDependenceAnalysis.cpp
index 1cd7dec..9d7bbbd 100644
--- a/lib/Analysis/MemoryDependenceAnalysis.cpp
+++ b/lib/Analysis/MemoryDependenceAnalysis.cpp
@@ -25,6 +25,7 @@
 #include "llvm/Analysis/InstructionSimplify.h"
 #include "llvm/Analysis/MemoryBuiltins.h"
 #include "llvm/Analysis/PHITransAddr.h"
+#include "llvm/Analysis/ValueTracking.h"
 #include "llvm/ADT/Statistic.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/Support/PredIteratorCache.h"
@@ -338,7 +339,7 @@ getPointerDependencyFrom(const AliasAnalysis::Location &MemLoc, bool isLoad,
     // need to continue scanning until the malloc call.
     if (isa<AllocaInst>(Inst) ||
         (isa<CallInst>(Inst) && extractMallocCall(Inst))) {
-      const Value *AccessPtr = MemLoc.Ptr->getUnderlyingObject();
+      const Value *AccessPtr = GetUnderlyingObject(MemLoc.Ptr);
       
       if (AccessPtr == Inst ||
           AA->alias(Inst, 1, AccessPtr, 1) == AliasAnalysis::MustAlias)
diff --git a/lib/Analysis/ValueTracking.cpp b/lib/Analysis/ValueTracking.cpp
index a612f13..d1b75c3 100644
--- a/lib/Analysis/ValueTracking.cpp
+++ b/lib/Analysis/ValueTracking.cpp
@@ -1426,3 +1426,23 @@ uint64_t llvm::GetStringLength(Value *V) {
   // an empty string as a length.
   return Len == ~0ULL ? 1 : Len;
 }
+
+Value *llvm::GetUnderlyingObject(Value *V, unsigned MaxLookup) {
+  if (!V->getType()->isPointerTy())
+    return V;
+  for (unsigned Count = 0; MaxLookup == 0 || Count < MaxLookup; ++Count) {
+    if (GEPOperator *GEP = dyn_cast<GEPOperator>(V)) {
+      V = GEP->getPointerOperand();
+    } else if (Operator::getOpcode(V) == Instruction::BitCast) {
+      V = cast<Operator>(V)->getOperand(0);
+    } else if (GlobalAlias *GA = dyn_cast<GlobalAlias>(V)) {
+      if (GA->mayBeOverridden())
+        return V;
+      V = GA->getAliasee();
+    } else {
+      return V;
+    }
+    assert(V->getType()->isPointerTy() && "Unexpected operand type!");
+  }
+  return V;
+}