Split DxilViewIdState::Compute into DxilViewIdStateBuilder. (#1595)

include/dxc/HLSL/ComputeViewIdState.h

@@ -44,7 +44,34 @@ class DxilModule;
 class DxilSignature;
 class DxilSignatureElement;
 
-class DxilViewIdState {
+struct DxilViewIdStateData {
+  static const unsigned kNumComps = 4;
+  static const unsigned kMaxSigScalars = 32*4;
+
+  using OutputsDependentOnViewIdType = std::bitset<kMaxSigScalars>;
+  using InputsContributingToOutputType = std::map<unsigned, std::set<unsigned>>;
+
+  static const unsigned kNumStreams = 4;
+
+  unsigned m_NumInputSigScalars  = 0;
+  unsigned m_NumOutputSigScalars[kNumStreams] = {0,0,0,0};
+  unsigned m_NumPCSigScalars     = 0;
+
+  // Set of scalar outputs dependent on ViewID.
+  OutputsDependentOnViewIdType m_OutputsDependentOnViewId[kNumStreams];
+  OutputsDependentOnViewIdType m_PCOutputsDependentOnViewId;
+
+  // Set of scalar inputs contributing to computation of scalar outputs.
+  InputsContributingToOutputType m_InputsContributingToOutputs[kNumStreams];
+  InputsContributingToOutputType m_InputsContributingToPCOutputs; // HS PC only.
+  InputsContributingToOutputType m_PCInputsContributingToOutputs; // DS only.
+
+  // Serialized form.
+  std::vector<unsigned> m_SerializedState;
+  bool m_bUsesViewId = false;
+};
+
+class DxilViewIdState : public DxilViewIdStateData {
   static const unsigned kNumComps = 4;
   static const unsigned kMaxSigScalars = 32*4;
 public:
@@ -62,118 +89,17 @@ public:
   const InputsContributingToOutputType &getInputsContributingToPCOutputs() const;
   const InputsContributingToOutputType &getPCInputsContributingToOutputs() const;
 
-  void Compute();
   void Serialize();
   const std::vector<unsigned> &GetSerialized();
-  const std::vector<unsigned> &GetSerialized() const;   // returns previously serialized data
+  const std::vector<unsigned> &
+  GetSerialized() const; // returns previously serialized data
   void Deserialize(const unsigned *pData, unsigned DataSizeInUINTs);
   void PrintSets(llvm::raw_ostream &OS);
 
 private:
-  static const unsigned kNumStreams = 4;
-
   DxilModule *m_pModule;
 
-  bool m_bUsesViewId = false;
-
-  unsigned m_NumInputSigScalars  = 0;
-  unsigned m_NumOutputSigScalars[kNumStreams] = {0,0,0,0};
-  unsigned m_NumPCSigScalars     = 0;
-
-  // Dynamically indexed components of signature elements.
-  using DynamicallyIndexedElemsType = std::unordered_map<unsigned, unsigned>;
-  DynamicallyIndexedElemsType m_InpSigDynIdxElems;
-  DynamicallyIndexedElemsType m_OutSigDynIdxElems;
-  DynamicallyIndexedElemsType m_PCSigDynIdxElems;
-
-  // Set of scalar outputs dependent on ViewID.
-  OutputsDependentOnViewIdType m_OutputsDependentOnViewId[kNumStreams];
-  OutputsDependentOnViewIdType m_PCOutputsDependentOnViewId;
-
-  // Set of scalar inputs contributing to computation of scalar outputs.
-  InputsContributingToOutputType m_InputsContributingToOutputs[kNumStreams];
-  InputsContributingToOutputType m_InputsContributingToPCOutputs; // HS PC only.
-  InputsContributingToOutputType m_PCInputsContributingToOutputs; // DS only.
-
-  // Information per entry point.
-  using FunctionSetType = std::unordered_set<llvm::Function *>;
-  using InstructionSetType = std::unordered_set<llvm::Instruction *>;
-  struct EntryInfo {
-    llvm::Function *pEntryFunc = nullptr;
-    // Sets of functions that may be reachable from an entry.
-    FunctionSetType Functions;
-    // Outputs to analyze.
-    InstructionSetType Outputs;
-    // Contributing instructions per output.
-    std::unordered_map<unsigned, InstructionSetType> ContributingInstructions[kNumStreams];
-
-    void Clear();
-  };
-
-  EntryInfo m_Entry;
-  EntryInfo m_PCEntry;
-
-  // Information per function.
-  using FunctionReturnSet = std::unordered_set<llvm::ReturnInst *>;
-  struct FuncInfo {
-    FunctionReturnSet Returns;
-    ControlDependence CtrlDep;
-    std::unique_ptr<llvm::DominatorTreeBase<llvm::BasicBlock> > pDomTree;
-    void Clear();
-  };
-
-  std::unordered_map<llvm::Function *, std::unique_ptr<FuncInfo>> m_FuncInfo;
-
-  // Cache of decls (global/alloca) reaching a pointer value.
-  using ValueSetType = std::unordered_set<llvm::Value *>;
-  std::unordered_map<llvm::Value *, ValueSetType> m_ReachingDeclsCache;
-  // Cache of stores for each decl.
-  std::unordered_map<llvm::Value *, ValueSetType> m_StoresPerDeclCache;
-
-  // Serialized form.
-  std::vector<unsigned> m_SerializedState;
-
   void Clear();
-  void DetermineMaxPackedLocation(DxilSignature &DxilSig, unsigned *pMaxSigLoc, unsigned NumStreams);
-  void ComputeReachableFunctionsRec(llvm::CallGraph &CG, llvm::CallGraphNode *pNode, FunctionSetType &FuncSet);
-  void AnalyzeFunctions(EntryInfo &Entry);
-  void CollectValuesContributingToOutputs(EntryInfo &Entry);
-  void CollectValuesContributingToOutputRec(EntryInfo &Entry,
-                                            llvm::Value *pContributingValue,
-                                            InstructionSetType &ContributingInstructions);
-  void CollectPhiCFValuesContributingToOutputRec(llvm::PHINode *pPhi,
-                                                 EntryInfo &Entry,
-                                                 InstructionSetType &ContributingInstructions);
-  const ValueSetType &CollectReachingDecls(llvm::Value *pValue);
-  void CollectReachingDeclsRec(llvm::Value *pValue, ValueSetType &ReachingDecls, ValueSetType &Visited);
-  const ValueSetType &CollectStores(llvm::Value *pValue);
-  void CollectStoresRec(llvm::Value *pValue, ValueSetType &Stores, ValueSetType &Visited);
-  void UpdateDynamicIndexUsageState() const;
-  void CreateViewIdSets(const std::unordered_map<unsigned, InstructionSetType> &ContributingInstructions,
-                        OutputsDependentOnViewIdType &OutputsDependentOnViewId,
-                        InputsContributingToOutputType &InputsContributingToOutputs, bool bPC);
-
-  void UpdateDynamicIndexUsageStateForSig(DxilSignature &Sig, const DynamicallyIndexedElemsType &DynIdxElems) const;
-  void SerializeOutputsDependentOnViewId(unsigned NumOutputs, 
-                                         const OutputsDependentOnViewIdType &OutputsDependentOnViewId,
-                                         unsigned *&pData);
-  void SerializeInputsContributingToOutput(unsigned NumInputs, unsigned NumOutputs,
-                                           const InputsContributingToOutputType &InputsContributingToOutputs,
-                                           unsigned *&pData);
-  unsigned DeserializeOutputsDependentOnViewId(unsigned NumOutputs, 
-                                               OutputsDependentOnViewIdType &OutputsDependentOnViewId,
-                                               const unsigned *pData, unsigned DataSize);
-  unsigned DeserializeInputsContributingToOutput(unsigned NumInputs, unsigned NumOutputs,
-                                                 InputsContributingToOutputType &InputsContributingToOutputs,
-                                                 const unsigned *pData, unsigned DataSize);
-  unsigned GetLinearIndex(DxilSignatureElement &SigElem, int row, unsigned col) const;
-
-  void PrintOutputsDependentOnViewId(llvm::raw_ostream &OS,
-                                     llvm::StringRef SetName, unsigned NumOutputs,
-                                     const OutputsDependentOnViewIdType &OutputsDependentOnViewId);
-  void PrintInputsContributingToOutputs(llvm::raw_ostream &OS,
-                                        llvm::StringRef InputSetName, llvm::StringRef OutputSetName,
-                                        const InputsContributingToOutputType &InputsContributingToOutputs);
 };
 
 } // end of hlsl namespace
@@ -181,17 +107,6 @@ private:
 
 namespace llvm {
 
-class ComputeViewIdState : public ModulePass {
-public:
-  static char ID; // Pass ID, replacement for typeid
-
-  ComputeViewIdState();
-
-  bool runOnModule(Module &M) override;
-
-  void getAnalysisUsage(AnalysisUsage &AU) const override;
-};
-
 void initializeComputeViewIdStatePass(llvm::PassRegistry &);
 llvm::ModulePass *createComputeViewIdStatePass();
 

include/dxc/HLSL/DxilModule.h

@@ -170,6 +170,7 @@ public:
   /// Serialize DXIL in-memory form to metadata form.
   void EmitDxilMetadata();
   /// Update resource metadata.
+  /// Note: this method not update Metadata for ViewIdState.
   void ReEmitDxilResources();
   /// Deserialize DXIL metadata form into in-memory form.
   void LoadDxilMetadata();

lib/HLSL/CMakeLists.txt

@@ -2,6 +2,7 @@
 # This file is distributed under the University of Illinois Open Source License. See LICENSE.TXT for details.
 add_llvm_library(LLVMHLSL
   ComputeViewIdState.cpp
+  ComputeViewIdStateBuilder.cpp
   ControlDependence.cpp
   DxilAddPixelHitInstrumentation.cpp
   DxilCBuffer.cpp

lib/HLSL/ComputeViewIdState.cpp

@@ -1,6 +1,6 @@
 ///////////////////////////////////////////////////////////////////////////////
 //                                                                           //
-// ComputeViewIdState.cpp                                                        //
+// ComputeViewIdState.cpp                                                    //
 // Copyright (C) Microsoft Corporation. All rights reserved.                 //
 // This file is distributed under the University of Illinois Open Source     //
 // License. See LICENSE.TXT for details.                                     //
@@ -49,65 +49,47 @@ const DxilViewIdState::InputsContributingToOutputType &DxilViewIdState::getInput
 const DxilViewIdState::InputsContributingToOutputType &DxilViewIdState::getInputsContributingToPCOutputs() const                { return m_InputsContributingToPCOutputs; }
 const DxilViewIdState::InputsContributingToOutputType &DxilViewIdState::getPCInputsContributingToOutputs() const                { return m_PCInputsContributingToOutputs; }
 
-void DxilViewIdState::Compute() {
-  Clear();
-
-  const ShaderModel *pSM = m_pModule->GetShaderModel();
-  m_bUsesViewId = m_pModule->m_ShaderFlags.GetViewID();
-
-  // 1. Traverse signature MD to determine max packed location.
-  DetermineMaxPackedLocation(m_pModule->GetInputSignature(), &m_NumInputSigScalars, 1);
-  DetermineMaxPackedLocation(m_pModule->GetOutputSignature(), &m_NumOutputSigScalars[0], pSM->IsGS() ? kNumStreams : 1);
-  DetermineMaxPackedLocation(m_pModule->GetPatchConstantSignature(), &m_NumPCSigScalars, 1);
-
-  // 2. Collect sets of functions reachable from main and pc entries.
-  CallGraphAnalysis CGA;
-  CallGraph CG = CGA.run(m_pModule->GetModule());
-  m_Entry.pEntryFunc = m_pModule->GetEntryFunction();
-  m_PCEntry.pEntryFunc = m_pModule->GetPatchConstantFunction();
-  ComputeReachableFunctionsRec(CG, CG[m_Entry.pEntryFunc], m_Entry.Functions);
-  if (m_PCEntry.pEntryFunc) {
-    DXASSERT_NOMSG(pSM->IsHS());
-    ComputeReachableFunctionsRec(CG, CG[m_PCEntry.pEntryFunc], m_PCEntry.Functions);
-  }
-
-  // 3. Determine shape components that are dynamically accesses and collect all sig outputs.
-  AnalyzeFunctions(m_Entry);
-  if (m_PCEntry.pEntryFunc) {
-    AnalyzeFunctions(m_PCEntry);
-  }
+namespace {
 
-  // 4. Collect sets of values contributing to outputs.
-  CollectValuesContributingToOutputs(m_Entry);
-  if (m_PCEntry.pEntryFunc) {
-    CollectValuesContributingToOutputs(m_PCEntry);
+void PrintOutputsDependentOnViewId(
+    llvm::raw_ostream &OS, llvm::StringRef SetName, unsigned NumOutputs,
+    const DxilViewIdState::OutputsDependentOnViewIdType
+        &OutputsDependentOnViewId) {
+  OS << SetName << " dependent on ViewId: { ";
+  bool bFirst = true;
+  for (unsigned i = 0; i < NumOutputs; i++) {
+    if (OutputsDependentOnViewId[i]) {
+      if (!bFirst)
+        OS << ", ";
+      OS << i;
+      bFirst = false;
+    }
   }
+  OS << " }\n";
+}
 
-  // 5. Construct dependency sets.
-  for (unsigned StreamId = 0; StreamId < (pSM->IsGS() ? kNumStreams : 1u); StreamId++) {
-    CreateViewIdSets(m_Entry.ContributingInstructions[StreamId],
-                     m_OutputsDependentOnViewId[StreamId],
-                     m_InputsContributingToOutputs[StreamId], false);
-  }
-  if (pSM->IsHS()) {
-    CreateViewIdSets(m_PCEntry.ContributingInstructions[0],
-                     m_PCOutputsDependentOnViewId,
-                     m_InputsContributingToPCOutputs, true);
-  } else if (pSM->IsDS()) {
-    OutputsDependentOnViewIdType OutputsDependentOnViewId;
-    CreateViewIdSets(m_Entry.ContributingInstructions[0],
-                     OutputsDependentOnViewId,
-                     m_PCInputsContributingToOutputs, true);
-    DXASSERT_NOMSG(OutputsDependentOnViewId == m_OutputsDependentOnViewId[0]);
+void PrintInputsContributingToOutputs(
+    llvm::raw_ostream &OS, llvm::StringRef InputSetName,
+    llvm::StringRef OutputSetName,
+    const DxilViewIdState::InputsContributingToOutputType
+        &InputsContributingToOutputs) {
+  OS << InputSetName << " contributing to computation of " << OutputSetName
+     << ":\n";
+  for (auto &it : InputsContributingToOutputs) {
+    unsigned outIdx = it.first;
+    auto &Inputs = it.second;
+    OS << "output " << outIdx << " depends on inputs: { ";
+    bool bFirst = true;
+    for (unsigned i : Inputs) {
+      if (!bFirst)
+        OS << ", ";
+      OS << i;
+      bFirst = false;
+    }
+    OS << " }\n";
   }
-
-  // 6. Update dynamically indexed input/output component masks.
-  UpdateDynamicIndexUsageState();
-
-#if DXILVIEWID_DBG
-  PrintSets(dbgs());
-#endif
 }
+} // namespace
 
 void DxilViewIdState::PrintSets(llvm::raw_ostream &OS) {
   const ShaderModel *pSM = m_pModule->GetShaderModel();
@@ -152,43 +134,7 @@ void DxilViewIdState::PrintSets(llvm::raw_ostream &OS) {
   OS << "\n";
 }
 
-void DxilViewIdState::PrintOutputsDependentOnViewId(llvm::raw_ostream &OS,
-                                                    llvm::StringRef SetName,
-                                                    unsigned NumOutputs,
-                                                    const OutputsDependentOnViewIdType &OutputsDependentOnViewId) {
-  OS << SetName << " dependent on ViewId: { ";
-  bool bFirst = true;
-  for (unsigned i = 0; i < NumOutputs; i++) {
-    if (OutputsDependentOnViewId[i]) {
-      if (!bFirst) OS << ", ";
-      OS << i;
-      bFirst = false;
-    }
-  }
-  OS << " }\n";
-}
-
-void DxilViewIdState::PrintInputsContributingToOutputs(llvm::raw_ostream &OS,
-                                                       llvm::StringRef InputSetName,
-                                                       llvm::StringRef OutputSetName,
-                                                       const InputsContributingToOutputType &InputsContributingToOutputs) {
-  OS << InputSetName << " contributing to computation of " << OutputSetName << ":\n";
-  for (auto &it : InputsContributingToOutputs) {
-    unsigned outIdx = it.first;
-    auto &Inputs = it.second;
-    OS << "output " << outIdx << " depends on inputs: { ";
-    bool bFirst = true;
-    for (unsigned i : Inputs) {
-      if (!bFirst) OS << ", ";
-      OS << i;
-      bFirst = false;
-    }
-    OS << " }\n";
-  }
-}
-
 void DxilViewIdState::Clear() {
-  m_bUsesViewId = false;
   m_NumInputSigScalars  = 0;
   for (unsigned i = 0; i < kNumStreams; i++) {
     m_NumOutputSigScalars[i] = 0;
@@ -196,602 +142,57 @@ void DxilViewIdState::Clear() {
     m_InputsContributingToOutputs[i].clear();
   }
   m_NumPCSigScalars     = 0;
-  m_InpSigDynIdxElems.clear();
-  m_OutSigDynIdxElems.clear();
-  m_PCSigDynIdxElems.clear();
   m_PCOutputsDependentOnViewId.reset();
   m_InputsContributingToPCOutputs.clear();
   m_PCInputsContributingToOutputs.clear();
-  m_Entry.Clear();
-  m_PCEntry.Clear();
-  m_FuncInfo.clear();
-  m_ReachingDeclsCache.clear();
   m_SerializedState.clear();
 }
 
-void DxilViewIdState::EntryInfo::Clear() {
-  pEntryFunc = nullptr;
-  Functions.clear();
-  Outputs.clear();
-  for (unsigned i = 0; i < kNumStreams; i++)
-    ContributingInstructions[i].clear();
-}
-
-void DxilViewIdState::FuncInfo::Clear() {
-  Returns.clear();
-  CtrlDep.Clear();
-  pDomTree.reset();
-}
-
-void DxilViewIdState::DetermineMaxPackedLocation(DxilSignature &DxilSig,
-                                                 unsigned *pMaxSigLoc,
-                                                 unsigned NumStreams) {
-  DXASSERT_NOMSG(NumStreams == 1 || NumStreams == kNumStreams);
-
-  for (unsigned i = 0; i < NumStreams; i++) {
-    pMaxSigLoc[i] = 0;
-  }
-
-  for (auto &E : DxilSig.GetElements()) {
-    if (E->GetStartRow() == Semantic::kUndefinedRow) continue;
-
-    unsigned StreamId = E->GetOutputStream();
-    unsigned endLoc = GetLinearIndex(*E, E->GetRows() - 1, E->GetCols() - 1);
-    pMaxSigLoc[StreamId] = std::max(pMaxSigLoc[StreamId], endLoc + 1);
-    E->GetCols();
-  }
-}
-
-void DxilViewIdState::ComputeReachableFunctionsRec(CallGraph &CG, CallGraphNode *pNode, FunctionSetType &FuncSet) {
-  Function *F = pNode->getFunction();
-  // Accumulate only functions with bodies.
-  if (F->empty()) return;
-  auto itIns = FuncSet.emplace(F);
-  DXASSERT_NOMSG(itIns.second);
-  (void)itIns;
-  for (auto it = pNode->begin(), itEnd = pNode->end(); it != itEnd; ++it) {
-    CallGraphNode *pSuccNode = it->second;
-    ComputeReachableFunctionsRec(CG, pSuccNode, FuncSet);
-  }
-}
-
-static bool GetUnsignedVal(Value *V, uint32_t *pValue) {
-  ConstantInt *CI = dyn_cast<ConstantInt>(V);
-  if (!CI) return false;
-  uint64_t u = CI->getZExtValue();
-  if (u > UINT32_MAX) return false;
-  *pValue = (uint32_t)u;
-  return true;
-}
-
-void DxilViewIdState::AnalyzeFunctions(EntryInfo &Entry) {
-  for (auto *F : Entry.Functions) {
-    DXASSERT_NOMSG(!F->empty());
-
-    auto itFI = m_FuncInfo.find(F);
-    FuncInfo *pFuncInfo = nullptr;
-    if (itFI != m_FuncInfo.end()) {
-      pFuncInfo = itFI->second.get();
-    } else {
-      m_FuncInfo[F] = make_unique<FuncInfo>();
-      pFuncInfo = m_FuncInfo[F].get();
-    }
-
-    for (auto itBB = F->begin(), endBB = F->end(); itBB != endBB; ++itBB) {
-      BasicBlock *BB = itBB;
-
-      for (auto itInst = BB->begin(), endInst = BB->end(); itInst != endInst; ++itInst) {
-        if (ReturnInst *RI = dyn_cast<ReturnInst>(itInst)) {
-          pFuncInfo->Returns.emplace(RI);
-          continue;
-        }
-
-        CallInst *CI = dyn_cast<CallInst>(itInst);
-        if (!CI) continue;
-
-        DynamicallyIndexedElemsType *pDynIdxElems = nullptr;
-        int row = Semantic::kUndefinedRow;
-        unsigned id, col;
-        if (DxilInst_LoadInput LI = DxilInst_LoadInput(CI)) {
-          pDynIdxElems = &m_InpSigDynIdxElems;
-          IFTBOOL(GetUnsignedVal(LI.get_inputSigId(), &id), DXC_E_GENERAL_INTERNAL_ERROR);
-          GetUnsignedVal(LI.get_rowIndex(), (uint32_t*)&row);
-          IFTBOOL(GetUnsignedVal(LI.get_colIndex(), &col), DXC_E_GENERAL_INTERNAL_ERROR);
-        } else if (DxilInst_StoreOutput SO = DxilInst_StoreOutput(CI)) {
-          pDynIdxElems = &m_OutSigDynIdxElems;
-          IFTBOOL(GetUnsignedVal(SO.get_outputSigId(), &id), DXC_E_GENERAL_INTERNAL_ERROR);
-          GetUnsignedVal(SO.get_rowIndex(), (uint32_t*)&row);
-          IFTBOOL(GetUnsignedVal(SO.get_colIndex(), &col), DXC_E_GENERAL_INTERNAL_ERROR);
-          Entry.Outputs.emplace(CI);
-        } else if (DxilInst_LoadPatchConstant LPC = DxilInst_LoadPatchConstant(CI)) {
-          if (m_pModule->GetShaderModel()->IsDS()) {
-            pDynIdxElems = &m_PCSigDynIdxElems;
-            IFTBOOL(GetUnsignedVal(LPC.get_inputSigId(), &id), DXC_E_GENERAL_INTERNAL_ERROR);
-            GetUnsignedVal(LPC.get_row(), (uint32_t*)&row);
-            IFTBOOL(GetUnsignedVal(LPC.get_col(), &col), DXC_E_GENERAL_INTERNAL_ERROR);
-          } else {
-            // Do nothing. This is an internal helper function for DXBC-2-DXIL converter.
-            DXASSERT_NOMSG(m_pModule->GetShaderModel()->IsHS());
-          }
-        } else if (DxilInst_StorePatchConstant SPC = DxilInst_StorePatchConstant(CI)) {
-          pDynIdxElems = &m_PCSigDynIdxElems;
-          IFTBOOL(GetUnsignedVal(SPC.get_outputSigID(), &id), DXC_E_GENERAL_INTERNAL_ERROR);
-          GetUnsignedVal(SPC.get_row(), (uint32_t*)&row);
-          IFTBOOL(GetUnsignedVal(SPC.get_col(), &col), DXC_E_GENERAL_INTERNAL_ERROR);
-          Entry.Outputs.emplace(CI);
-        } else if (DxilInst_LoadOutputControlPoint LOCP = DxilInst_LoadOutputControlPoint(CI)) {
-          if (m_pModule->GetShaderModel()->IsDS()) {
-            pDynIdxElems = &m_InpSigDynIdxElems;
-            IFTBOOL(GetUnsignedVal(LOCP.get_inputSigId(), &id), DXC_E_GENERAL_INTERNAL_ERROR);
-            GetUnsignedVal(LOCP.get_row(), (uint32_t*)&row);
-            IFTBOOL(GetUnsignedVal(LOCP.get_col(), &col), DXC_E_GENERAL_INTERNAL_ERROR);
-          } else if (m_pModule->GetShaderModel()->IsHS()) {
-            // Do nothings, as the information has been captured by the output signature of CP entry.
-          } else {
-            DXASSERT_NOMSG(false);
-          }
-        } else {
-          continue;
-        }
-
-        // Record dynamic index usage.
-        if (pDynIdxElems && row == Semantic::kUndefinedRow) {
-          (*pDynIdxElems)[id] |= (1 << col);
-        }
-      }
-    }
-
-    // Compute dominator relation.
-    pFuncInfo->pDomTree = make_unique<DominatorTreeBase<BasicBlock> >(false);
-    pFuncInfo->pDomTree->recalculate(*F);
-#if DXILVIEWID_DBG
-    pFuncInfo->pDomTree->print(dbgs());
-#endif
-
-    // Compute postdominator relation.
-    DominatorTreeBase<BasicBlock> PDR(true);
-    PDR.recalculate(*F);
-#if DXILVIEWID_DBG
-    PDR.print(dbgs());
-#endif
-    // Compute control dependence.
-    pFuncInfo->CtrlDep.Compute(F, PDR);
-#if DXILVIEWID_DBG
-    pFuncInfo->CtrlDep.print(dbgs());
-#endif
-  }
-}
-
-void DxilViewIdState::CollectValuesContributingToOutputs(EntryInfo &Entry) {
-  for (auto *CI : Entry.Outputs) {  // CI = call instruction
-    DxilSignature *pDxilSig = nullptr;
-    Value *pContributingValue = nullptr;
-    unsigned id = (unsigned)-1;
-    int startRow = Semantic::kUndefinedRow, endRow = Semantic::kUndefinedRow;
-    unsigned col = (unsigned)-1;
-    if (DxilInst_StoreOutput SO = DxilInst_StoreOutput(CI)) {
-      pDxilSig = &m_pModule->GetOutputSignature();
-      pContributingValue = SO.get_value();
-      GetUnsignedVal(SO.get_outputSigId(), &id);
-      GetUnsignedVal(SO.get_colIndex(), &col);
-      GetUnsignedVal(SO.get_rowIndex(), (uint32_t*)&startRow);
-    } else if (DxilInst_StorePatchConstant SPC = DxilInst_StorePatchConstant(CI)) {
-      pDxilSig = &m_pModule->GetPatchConstantSignature();
-      pContributingValue = SPC.get_value();
-      GetUnsignedVal(SPC.get_outputSigID(), &id);
-      GetUnsignedVal(SPC.get_row(), (uint32_t*)&startRow);
-      GetUnsignedVal(SPC.get_col(), &col);
-    } else {
-      IFT(DXC_E_GENERAL_INTERNAL_ERROR);
-    }
-
-    DxilSignatureElement &SigElem = pDxilSig->GetElement(id);
-    if (!SigElem.IsAllocated())
-      continue;
-
-    unsigned StreamId = SigElem.GetOutputStream();
-
-    if (startRow != Semantic::kUndefinedRow) {
-      endRow = startRow;
-    } else {
-      // The entire column is affected by value.
-      DXASSERT_NOMSG(SigElem.GetID() == id && SigElem.GetStartRow() != Semantic::kUndefinedRow);
-      startRow = 0;
-      endRow = SigElem.GetRows() - 1;
-    }
-
-    InstructionSetType ContributingInstructionsAllRows;
-    InstructionSetType *pContributingInstructions = &ContributingInstructionsAllRows;
-    if (startRow == endRow) {
-      // Scalar or indexable with known index.
-      unsigned index = GetLinearIndex(SigElem, startRow, col);
-      pContributingInstructions = &Entry.ContributingInstructions[StreamId][index];
-    }
-
-    CollectValuesContributingToOutputRec(Entry, pContributingValue, *pContributingInstructions);
-
-    // Handle control dependence of this instruction BB.
-    BasicBlock *pBB = CI->getParent();
-    Function *F = pBB->getParent();
-    FuncInfo *pFuncInfo = m_FuncInfo[F].get();
-    const BasicBlockSet &CtrlDepSet = pFuncInfo->CtrlDep.GetCDBlocks(pBB);
-    for (BasicBlock *B : CtrlDepSet) {
-      CollectValuesContributingToOutputRec(Entry, B->getTerminator(), *pContributingInstructions);
-    }
-
-    if (pContributingInstructions == &ContributingInstructionsAllRows) {
-      // Write dynamically indexed output contributions to all rows.
-      for (int row = startRow; row <= endRow; row++) {
-        unsigned index = GetLinearIndex(SigElem, row, col);
-        Entry.ContributingInstructions[StreamId][index].insert(ContributingInstructionsAllRows.begin(), ContributingInstructionsAllRows.end());
-      }
-    }
-  }
-}
-
-void DxilViewIdState::CollectValuesContributingToOutputRec(EntryInfo &Entry,
-                                                           Value *pContributingValue,
-                                                           InstructionSetType &ContributingInstructions) {
-  if (dyn_cast<Argument>(pContributingValue)) {
-    // This must be a leftover signature argument of an entry function.
-    DXASSERT_NOMSG(Entry.pEntryFunc == m_pModule->GetEntryFunction() ||
-                   Entry.pEntryFunc == m_pModule->GetPatchConstantFunction());
-    return;
-  }
+namespace {
 
-  Instruction *pContributingInst = dyn_cast<Instruction>(pContributingValue);
-  if (pContributingInst == nullptr) {
-    // Can be literal constant, global decl, branch target.
-    DXASSERT_NOMSG(isa<Constant>(pContributingValue) || isa<BasicBlock>(pContributingValue));
-    return;
-  }
+unsigned RoundUpToUINT(unsigned x) { return (x + 31) / 32; }
 
-  auto itInst = ContributingInstructions.emplace(pContributingInst);
-  // Already visited instruction.
-  if (!itInst.second) return;
-
-  // Handle special cases.
-  if (PHINode *phi = dyn_cast<PHINode>(pContributingInst)) {
-    CollectPhiCFValuesContributingToOutputRec(phi, Entry, ContributingInstructions);
-  } else if (isa<LoadInst>(pContributingInst) || 
-             isa<AtomicCmpXchgInst>(pContributingInst) ||
-             isa<AtomicRMWInst>(pContributingInst)) {
-    Value *pPtrValue = pContributingInst->getOperand(0);
-    DXASSERT_NOMSG(pPtrValue->getType()->isPointerTy());
-    const ValueSetType &ReachingDecls = CollectReachingDecls(pPtrValue);
-    DXASSERT_NOMSG(ReachingDecls.size() > 0);
-    for (Value *pDeclValue : ReachingDecls) {
-      const ValueSetType &Stores = CollectStores(pDeclValue);
-      for (Value *V : Stores) {
-        CollectValuesContributingToOutputRec(Entry, V, ContributingInstructions);
-      }
-    }
-  } else if (CallInst *CI = dyn_cast<CallInst>(pContributingInst)) {
-    if (!hlsl::OP::IsDxilOpFuncCallInst(CI)) {
-      Function *F = CI->getCalledFunction();
-      if (!F->empty()) {
-        // Return value of a user function.
-        if (Entry.Functions.find(F) != Entry.Functions.end()) {
-          const FuncInfo &FI = *m_FuncInfo[F];
-          for (ReturnInst *pRetInst : FI.Returns) {
-            CollectValuesContributingToOutputRec(Entry, pRetInst, ContributingInstructions);
-          }
-        }
-      }
-    }
-  }
-
-  // Handle instruction inputs.
-  unsigned NumOps = pContributingInst->getNumOperands();
-  for (unsigned i = 0; i < NumOps; i++) {
-    Value *O = pContributingInst->getOperand(i);
-    CollectValuesContributingToOutputRec(Entry, O, ContributingInstructions);
-  }
-
-  // Handle control dependence of this instruction BB.
-  BasicBlock *pBB = pContributingInst->getParent();
-  Function *F = pBB->getParent();
-  FuncInfo *pFuncInfo = m_FuncInfo[F].get();
-  const BasicBlockSet &CtrlDepSet = pFuncInfo->CtrlDep.GetCDBlocks(pBB);
-  for (BasicBlock *B : CtrlDepSet) {
-    CollectValuesContributingToOutputRec(Entry, B->getTerminator(), ContributingInstructions);
-  }
-}
-
-// Only process control-dependent basic blocks for constant operands of the phi-function.
-// An obvious "definition" point for a constant operand is the predecessor along corresponding edge.
-// However, this may be too conservative and, as such, pick up extra control dependent BBs.
-// A better "definition" point is the highest dominator where it is still legal to "insert" constant assignment.
-// In this context, "legal" means that only one value "leaves" the dominator and reaches Phi.
-void DxilViewIdState::CollectPhiCFValuesContributingToOutputRec(PHINode *pPhi,
-                                                                EntryInfo &Entry,
-                                                                InstructionSetType &ContributingInstructions) {
-  Function *F = pPhi->getParent()->getParent();
-  FuncInfo *pFuncInfo = m_FuncInfo[F].get();
-  unordered_map<DomTreeNodeBase<BasicBlock> *, Value *> DomTreeMarkers;
-
-  // Mark predecessors of each value, so that there is a legal "definition" point.
-  for (unsigned i = 0; i < pPhi->getNumOperands(); i++) {
-    Value *pValue = pPhi->getIncomingValue(i);
-    BasicBlock *pBB = pPhi->getIncomingBlock(i);
-    DomTreeNodeBase<BasicBlock> *pDomNode = pFuncInfo->pDomTree->getNode(pBB);
-    auto it = DomTreeMarkers.emplace(pDomNode, pValue);
-    DXASSERT_NOMSG(it.second || it.first->second == pValue); (void)it;
-  }
-  // Mark the dominator tree with "definition" values, walking up to the parent.
-  for (unsigned i = 0; i < pPhi->getNumOperands(); i++) {
-    Value *pValue = pPhi->getIncomingValue(i);
-    BasicBlock *pDefBB = &F->getEntryBlock();
-    if (Instruction *pDefInst = dyn_cast<Instruction>(pValue)) {
-      pDefBB = pDefInst->getParent();
-    }
-
-    BasicBlock *pBB = pPhi->getIncomingBlock(i);
-    if (pBB == pDefBB) {
-      continue; // we already handled the predecessor.
-    }
-    DomTreeNodeBase<BasicBlock> *pDomNode = pFuncInfo->pDomTree->getNode(pBB);
-    pDomNode = pDomNode->getIDom();
-    while (pDomNode) {
-      auto it = DomTreeMarkers.emplace(pDomNode, pValue);
-      if (!it.second) {
-        if (it.first->second != pValue && it.first->second != nullptr) {
-          if (!isa<Constant>(it.first->second) || !isa<Constant>(pValue)) {
-            // Unless both are different constants, mark the "definition" point as illegal.
-            it.first->second = nullptr;
-            // If both are constants, leave the marker of the first one.
-          }
-        }
-        break;
-      }
-
-      // Do not go higher than a legal definition point.
-      pBB = pDomNode->getBlock();
-      if (pBB == pDefBB)
-        break;
-
-      pDomNode = pDomNode->getIDom();
-    }
-  }
-
-  // Handle control dependence for Constant arguments of Phi.
-  for (unsigned i = 0; i < pPhi->getNumOperands(); i++) {
-    Value *pValue = pPhi->getIncomingValue(i);
-    if (!isa<Constant>(pValue))
-      continue;
+void SerializeOutputsDependentOnViewId(
+    unsigned NumOutputs,
+    const DxilViewIdState::OutputsDependentOnViewIdType
+        &OutputsDependentOnViewId,
+    unsigned *&pData) {
+  unsigned NumOutUINTs = RoundUpToUINT(NumOutputs);
 
-    // Determine the higher legal "definition" point.
-    BasicBlock *pBB = pPhi->getIncomingBlock(i);
-    DomTreeNodeBase<BasicBlock> *pDomNode = pFuncInfo->pDomTree->getNode(pBB);
-    DomTreeNodeBase<BasicBlock> *pDefDomNode = pDomNode;
-    while (pDomNode) {
-      auto it = DomTreeMarkers.find(pDomNode);
-      DXASSERT_NOMSG(it != DomTreeMarkers.end());
-      if (it->second != pValue) {
-        DXASSERT_NOMSG(it->second == nullptr || isa<Constant>(it->second));
-        break;
+  // Serialize output dependence on ViewId.
+  for (unsigned i = 0; i < NumOutUINTs; i++) {
+    unsigned x = 0;
+    for (unsigned j = 0; j < std::min(32u, NumOutputs - 32u * i); j++) {
+      if (OutputsDependentOnViewId[i * 32 + j]) {
+        x |= (1u << j);
       }
-
-      pDefDomNode = pDomNode;
-      pDomNode = pDomNode->getIDom();
     }
-
-    // Handle control dependence of this constant argument highest legal "definition" point.
-    pBB = pDefDomNode->getBlock();
-    const BasicBlockSet &CtrlDepSet = pFuncInfo->CtrlDep.GetCDBlocks(pBB);
-    for (BasicBlock *B : CtrlDepSet) {
-      CollectValuesContributingToOutputRec(Entry, B->getTerminator(), ContributingInstructions);
-    }
-  }
-}
-
-const DxilViewIdState::ValueSetType &DxilViewIdState::CollectReachingDecls(Value *pValue) {
-  auto it = m_ReachingDeclsCache.emplace(pValue, ValueSetType());
-  if (it.second) {
-    // We have not seen this value before.
-    ValueSetType Visited;
-    CollectReachingDeclsRec(pValue, it.first->second, Visited);
-  }
-  return it.first->second;
-}
-
-void DxilViewIdState::CollectReachingDeclsRec(Value *pValue, ValueSetType &ReachingDecls, ValueSetType &Visited) {
-  if (Visited.find(pValue) != Visited.end())
-    return;
-
-  bool bInitialValue = Visited.size() == 0;
-  Visited.emplace(pValue);
-
-  if (!bInitialValue) {
-    auto it = m_ReachingDeclsCache.find(pValue);
-    if (it != m_ReachingDeclsCache.end()) {
-      ReachingDecls.insert(it->second.begin(), it->second.end());
-      return;
-    }
-  }
-
-  if (dyn_cast<GlobalVariable>(pValue)) {
-    ReachingDecls.emplace(pValue);
-    return;
-  }
-
-  if (GetElementPtrInst *pGepInst = dyn_cast<GetElementPtrInst>(pValue)) {
-    Value *pPtrValue = pGepInst->getPointerOperand();
-    CollectReachingDeclsRec(pPtrValue, ReachingDecls, Visited);
-  } else if (GEPOperator *pGepOp = dyn_cast<GEPOperator>(pValue)) {
-    Value *pPtrValue = pGepOp->getPointerOperand();
-    CollectReachingDeclsRec(pPtrValue, ReachingDecls, Visited);
-  } else if (dyn_cast<AllocaInst>(pValue)) {
-    ReachingDecls.emplace(pValue);
-  } else if (PHINode *phi = dyn_cast<PHINode>(pValue)) {
-    for (Value *pPtrValue : phi->operands()) {
-      CollectReachingDeclsRec(pPtrValue, ReachingDecls, Visited);
-    }
-  } else if (SelectInst *SelI = dyn_cast<SelectInst>(pValue)) {
-    CollectReachingDeclsRec(SelI->getTrueValue(), ReachingDecls, Visited);
-    CollectReachingDeclsRec(SelI->getFalseValue(), ReachingDecls, Visited);
-  } else if (dyn_cast<Argument>(pValue)) {
-    ReachingDecls.emplace(pValue);
-  } else {
-    IFT(DXC_E_GENERAL_INTERNAL_ERROR);
-  }
-}
-
-const DxilViewIdState::ValueSetType &DxilViewIdState::CollectStores(llvm::Value *pValue) {
-  auto it = m_StoresPerDeclCache.emplace(pValue, ValueSetType());
-  if (it.second) {
-    // We have not seen this value before.
-    ValueSetType Visited;
-    CollectStoresRec(pValue, it.first->second, Visited);
-  }
-  return it.first->second;
-}
-
-void DxilViewIdState::CollectStoresRec(llvm::Value *pValue, ValueSetType &Stores, ValueSetType &Visited) {
-  if (Visited.find(pValue) != Visited.end())
-    return;
-
-  bool bInitialValue = Visited.size() == 0;
-  Visited.emplace(pValue);
-
-  if (!bInitialValue) {
-    auto it = m_StoresPerDeclCache.find(pValue);
-    if (it != m_StoresPerDeclCache.end()) {
-      Stores.insert(it->second.begin(), it->second.end());
-      return;
-    }
-  }
-
-  if (isa<LoadInst>(pValue)) {
-    return;
-  } else if (isa<StoreInst>(pValue) ||
-             isa<AtomicCmpXchgInst>(pValue) ||
-             isa<AtomicRMWInst>(pValue)) {
-    Stores.emplace(pValue);
-    return;
-  }
-
-  for (auto *U : pValue->users()) {
-    CollectStoresRec(U, Stores, Visited);
+    *pData++ = x;
   }
 }
 
-void DxilViewIdState::CreateViewIdSets(const std::unordered_map<unsigned, InstructionSetType> &ContributingInstructions, 
-                                       OutputsDependentOnViewIdType &OutputsDependentOnViewId,
-                                       InputsContributingToOutputType &InputsContributingToOutputs,
-                                       bool bPC) {
-  const ShaderModel *pSM = m_pModule->GetShaderModel();
-
-  for (auto &itOut : ContributingInstructions) {
-    unsigned outIdx = itOut.first;
-    for (Instruction *pInst : itOut.second) {
-      // Set output dependence on ViewId.
-      if (DxilInst_ViewID VID = DxilInst_ViewID(pInst)) {
-        DXASSERT(m_bUsesViewId, "otherwise, DxilModule flag not set properly");
-        OutputsDependentOnViewId[outIdx] = true;
-        continue;
-      }
-
-      // Start setting output dependence on inputs.
-      DxilSignatureElement *pSigElem = nullptr;
-      bool bLoadOutputCPInHS = false;
-      unsigned inpId = (unsigned)-1;
-      int startRow = Semantic::kUndefinedRow, endRow = Semantic::kUndefinedRow;
-      unsigned col = (unsigned)-1;
-      if (DxilInst_LoadInput LI = DxilInst_LoadInput(pInst)) {
-        GetUnsignedVal(LI.get_inputSigId(), &inpId);
-        GetUnsignedVal(LI.get_colIndex(), &col);
-        GetUnsignedVal(LI.get_rowIndex(), (uint32_t*)&startRow);
-        pSigElem = &m_pModule->GetInputSignature().GetElement(inpId);
-        if (pSM->IsDS() && bPC) {
-          pSigElem = nullptr;
-        }
-      } else if (DxilInst_LoadOutputControlPoint LOCP = DxilInst_LoadOutputControlPoint(pInst)) {
-        GetUnsignedVal(LOCP.get_inputSigId(), &inpId);
-        GetUnsignedVal(LOCP.get_col(), &col);
-        GetUnsignedVal(LOCP.get_row(), (uint32_t*)&startRow);
-        if (pSM->IsHS()) {
-          pSigElem = &m_pModule->GetOutputSignature().GetElement(inpId);
-          bLoadOutputCPInHS = true;
-        } else if (pSM->IsDS()) {
-          if (!bPC) {
-            pSigElem = &m_pModule->GetInputSignature().GetElement(inpId);
-          }
-        } else {
-          DXASSERT_NOMSG(false);
-        }
-      } else if (DxilInst_LoadPatchConstant LPC = DxilInst_LoadPatchConstant(pInst)) {
-        if (pSM->IsDS() && bPC) {
-          GetUnsignedVal(LPC.get_inputSigId(), &inpId);
-          GetUnsignedVal(LPC.get_col(), &col);
-          GetUnsignedVal(LPC.get_row(), (uint32_t*)&startRow);
-          pSigElem = &m_pModule->GetPatchConstantSignature().GetElement(inpId);
-        }
-      } else {
-        continue;
-      }
-
-      // Finalize setting output dependence on inputs.
-      if (pSigElem && pSigElem->IsAllocated()) {
-        if (startRow != Semantic::kUndefinedRow) {
-          endRow = startRow;
-        } else {
-          // The entire column contributes to output.
-          startRow = 0;
-          endRow = pSigElem->GetRows() - 1;
-        }
-
-        auto &ContributingInputs = InputsContributingToOutputs[outIdx];
-        for (int row = startRow; row <= endRow; row++) {
-          unsigned index = GetLinearIndex(*pSigElem, row, col);
-          if (!bLoadOutputCPInHS) {
-            ContributingInputs.emplace(index);
-          } else {
-            // This HS patch-constant output depends on an input value of LoadOutputControlPoint
-            // that is the output value of the HS main (control-point) function.
-            // Transitively update this (patch-constant) output dependence on main (control-point) output.
-            DXASSERT_NOMSG(&OutputsDependentOnViewId == &m_PCOutputsDependentOnViewId);
-            OutputsDependentOnViewId[outIdx] = OutputsDependentOnViewId[outIdx] || m_OutputsDependentOnViewId[0][index];
+void SerializeInputsContributingToOutput(
+    unsigned NumInputs, unsigned NumOutputs,
+    const DxilViewIdState::InputsContributingToOutputType
+        &InputsContributingToOutputs,
+    unsigned *&pData) {
+  unsigned NumOutUINTs = RoundUpToUINT(NumOutputs);
 
-            const auto it = m_InputsContributingToOutputs[0].find(index);
-            if (it != m_InputsContributingToOutputs[0].end()) {
-              const std::set<unsigned> &LoadOutputCPInputsContributingToOutputs = it->second;
-              ContributingInputs.insert(LoadOutputCPInputsContributingToOutputs.begin(),
-                                        LoadOutputCPInputsContributingToOutputs.end());
-            }
-          }
-        }
+  // Serialize output dependence on inputs.
+  for (unsigned outputIdx = 0; outputIdx < NumOutputs; outputIdx++) {
+    auto it = InputsContributingToOutputs.find(outputIdx);
+    if (it != InputsContributingToOutputs.end()) {
+      for (unsigned inputIdx : it->second) {
+        unsigned w = outputIdx / 32;
+        unsigned b = outputIdx % 32;
+        pData[inputIdx * NumOutUINTs + w] |= (1u << b);
       }
     }
   }
-}
-
-unsigned DxilViewIdState::GetLinearIndex(DxilSignatureElement &SigElem, int row, unsigned col) const {
-  DXASSERT_NOMSG(row >= 0 && col < kNumComps && SigElem.GetStartRow() != Semantic::kUndefinedRow);
-  unsigned idx = (((unsigned)row) + SigElem.GetStartRow())*kNumComps + col + SigElem.GetStartCol();
-  DXASSERT_NOMSG(idx < kMaxSigScalars);
-  return idx;
-}
-
-void DxilViewIdState::UpdateDynamicIndexUsageState() const {
-  UpdateDynamicIndexUsageStateForSig(m_pModule->GetInputSignature(), m_InpSigDynIdxElems);
-  UpdateDynamicIndexUsageStateForSig(m_pModule->GetOutputSignature(), m_OutSigDynIdxElems);
-  UpdateDynamicIndexUsageStateForSig(m_pModule->GetPatchConstantSignature(), m_PCSigDynIdxElems);
-}
-
-void DxilViewIdState::UpdateDynamicIndexUsageStateForSig(DxilSignature &Sig,
-                                                         const DynamicallyIndexedElemsType &DynIdxElems) const {
-  for (auto it : DynIdxElems) {
-    unsigned id = it.first;
-    unsigned mask = it.second;
-    DxilSignatureElement &E = Sig.GetElement(id);
-    E.SetDynIdxCompMask(mask);
-  }
-}
 
-static unsigned RoundUpToUINT(unsigned x) {
-  return (x + 31)/32;
+  pData += NumInputs * NumOutUINTs;
 }
+} // namespace
 
 void DxilViewIdState::Serialize() {
   const ShaderModel *pSM = m_pModule->GetShaderModel();
@@ -799,31 +200,31 @@ void DxilViewIdState::Serialize() {
 
   // Compute serialized state size in UINTs.
   unsigned NumInputs = getNumInputSigScalars();
-  unsigned NumStreams = pSM->IsGS()? kNumStreams : 1;
+  unsigned NumStreams = pSM->IsGS() ? kNumStreams : 1;
   unsigned Size = 0;
-  Size += 1;  // #Inputs.
+  Size += 1; // #Inputs.
   for (unsigned StreamId = 0; StreamId < NumStreams; StreamId++) {
-    Size += 1;  // #Outputs for stream StreamId.
+    Size += 1; // #Outputs for stream StreamId.
     unsigned NumOutputs = getNumOutputSigScalars(StreamId);
     unsigned NumOutUINTs = RoundUpToUINT(NumOutputs);
     if (m_bUsesViewId) {
-      Size += NumOutUINTs;  // m_OutputsDependentOnViewId[StreamId]
+      Size += NumOutUINTs; // m_OutputsDependentOnViewId[StreamId]
     }
-    Size += NumInputs * NumOutUINTs;  // m_InputsContributingToOutputs[StreamId]
+    Size += NumInputs * NumOutUINTs; // m_InputsContributingToOutputs[StreamId]
   }
   if (pSM->IsHS() || pSM->IsDS()) {
-    Size += 1;  // #PatchConstant.
+    Size += 1; // #PatchConstant.
     unsigned NumPCs = getNumPCSigScalars();
     unsigned NumPCUINTs = RoundUpToUINT(NumPCs);
     if (pSM->IsHS()) {
       if (m_bUsesViewId) {
-        Size += NumPCUINTs;  // m_PCOutputsDependentOnViewId
+        Size += NumPCUINTs; // m_PCOutputsDependentOnViewId
       }
       Size += NumInputs * NumPCUINTs; // m_InputsContributingToPCOutputs
     } else {
       unsigned NumOutputs = getNumOutputSigScalars(0);
       unsigned NumOutUINTs = RoundUpToUINT(NumOutputs);
-      Size += NumPCs * NumOutUINTs;   // m_PCInputsContributingToOutputs
+      Size += NumPCs * NumOutUINTs; // m_PCInputsContributingToOutputs
     }
   }
 
@@ -837,21 +238,26 @@ void DxilViewIdState::Serialize() {
     unsigned NumOutputs = getNumOutputSigScalars(StreamId);
     *pData++ = NumOutputs;
     if (m_bUsesViewId) {
-      SerializeOutputsDependentOnViewId(NumOutputs, m_OutputsDependentOnViewId[StreamId], pData);
+      SerializeOutputsDependentOnViewId(
+          NumOutputs, m_OutputsDependentOnViewId[StreamId], pData);
     }
-    SerializeInputsContributingToOutput(NumInputs, NumOutputs, m_InputsContributingToOutputs[StreamId], pData);
+    SerializeInputsContributingToOutput(
+        NumInputs, NumOutputs, m_InputsContributingToOutputs[StreamId], pData);
   }
   if (pSM->IsHS() || pSM->IsDS()) {
     unsigned NumPCs = getNumPCSigScalars();
     *pData++ = NumPCs;
     if (pSM->IsHS()) {
       if (m_bUsesViewId) {
-        SerializeOutputsDependentOnViewId(NumPCs, m_PCOutputsDependentOnViewId, pData);
+        SerializeOutputsDependentOnViewId(NumPCs, m_PCOutputsDependentOnViewId,
+                                          pData);
       }
-      SerializeInputsContributingToOutput(NumInputs, NumPCs, m_InputsContributingToPCOutputs, pData);
+      SerializeInputsContributingToOutput(
+          NumInputs, NumPCs, m_InputsContributingToPCOutputs, pData);
     } else {
       unsigned NumOutputs = getNumOutputSigScalars(0);
-      SerializeInputsContributingToOutput(NumPCs, NumOutputs, m_PCInputsContributingToOutputs, pData);
+      SerializeInputsContributingToOutput(
+          NumPCs, NumOutputs, m_PCInputsContributingToOutputs, pData);
     }
   }
   DXASSERT_NOMSG(pData == (&m_SerializedState[0] + Size));
@@ -867,44 +273,53 @@ const vector<unsigned> &DxilViewIdState::GetSerialized() const {
   return m_SerializedState;
 }
 
-void DxilViewIdState::SerializeOutputsDependentOnViewId(unsigned NumOutputs, 
-                                                        const OutputsDependentOnViewIdType &OutputsDependentOnViewId,
-                                                        unsigned *&pData) {
+namespace {
+unsigned DeserializeOutputsDependentOnViewId(
+    unsigned NumOutputs,
+    DxilViewIdState::OutputsDependentOnViewIdType &OutputsDependentOnViewId,
+    const unsigned *pData, unsigned DataSize) {
   unsigned NumOutUINTs = RoundUpToUINT(NumOutputs);
+  IFTBOOL(NumOutUINTs <= DataSize, DXC_E_GENERAL_INTERNAL_ERROR);
 
-  // Serialize output dependence on ViewId.
+  // Deserialize output dependence on ViewId.
   for (unsigned i = 0; i < NumOutUINTs; i++) {
-    unsigned x = 0;
-    for (unsigned j = 0; j < std::min(32u, NumOutputs - 32u*i); j++) {
-      if (OutputsDependentOnViewId[i*32 + j]) {
-        x |= (1u << j);
+    unsigned x = *pData++;
+    for (unsigned j = 0; j < std::min(32u, NumOutputs - 32u * i); j++) {
+      if (x & (1u << j)) {
+        OutputsDependentOnViewId[i * 32 + j] = true;
       }
     }
-    *pData++ = x;
   }
+
+  return NumOutUINTs;
 }
 
-void DxilViewIdState::SerializeInputsContributingToOutput(unsigned NumInputs, unsigned NumOutputs,
-                                                          const InputsContributingToOutputType &InputsContributingToOutputs,
-                                                          unsigned *&pData) {
+unsigned DeserializeInputsContributingToOutput(
+    unsigned NumInputs, unsigned NumOutputs,
+    DxilViewIdState::InputsContributingToOutputType
+        &InputsContributingToOutputs,
+    const unsigned *pData, unsigned DataSize) {
   unsigned NumOutUINTs = RoundUpToUINT(NumOutputs);
+  unsigned Size = NumInputs * NumOutUINTs;
+  IFTBOOL(Size <= DataSize, DXC_E_GENERAL_INTERNAL_ERROR);
 
-  // Serialize output dependence on inputs.
-  for (unsigned outputIdx = 0; outputIdx < NumOutputs; outputIdx++) {
-    auto it = InputsContributingToOutputs.find(outputIdx);
-    if (it != InputsContributingToOutputs.end()) {
-      for (unsigned inputIdx : it->second) {
-        unsigned w = outputIdx / 32;
-        unsigned b = outputIdx % 32;
-        pData[inputIdx*NumOutUINTs + w] |= (1u << b);
+  // Deserialize output dependence on inputs.
+  for (unsigned inputIdx = 0; inputIdx < NumInputs; inputIdx++) {
+    for (unsigned outputIdx = 0; outputIdx < NumOutputs; outputIdx++) {
+      unsigned w = outputIdx / 32;
+      unsigned b = outputIdx % 32;
+      if (pData[inputIdx * NumOutUINTs + w] & (1u << b)) {
+        InputsContributingToOutputs[outputIdx].insert(inputIdx);
       }
     }
   }
 
-  pData += NumInputs * NumOutUINTs;
+  return Size;
 }
+} // namespace
 
-void DxilViewIdState::Deserialize(const unsigned *pData, unsigned DataSizeInUINTs) {
+void DxilViewIdState::Deserialize(const unsigned *pData,
+                                  unsigned DataSizeInUINTs) {
   Clear();
   m_SerializedState.resize(DataSizeInUINTs);
   memcpy(m_SerializedState.data(), pData, DataSizeInUINTs * sizeof(unsigned));
@@ -913,125 +328,46 @@ void DxilViewIdState::Deserialize(const unsigned *pData, unsigned DataSizeInUINT
   m_bUsesViewId = m_pModule->m_ShaderFlags.GetViewID();
   unsigned ConsumedUINTs = 0;
 
-  IFTBOOL(DataSizeInUINTs-ConsumedUINTs >= 1, DXC_E_GENERAL_INTERNAL_ERROR);
+  IFTBOOL(DataSizeInUINTs - ConsumedUINTs >= 1, DXC_E_GENERAL_INTERNAL_ERROR);
   unsigned NumInputs = pData[ConsumedUINTs++];
   m_NumInputSigScalars = NumInputs;
 
-  unsigned NumStreams = pSM->IsGS()? kNumStreams : 1;
+  unsigned NumStreams = pSM->IsGS() ? kNumStreams : 1;
   for (unsigned StreamId = 0; StreamId < NumStreams; StreamId++) {
-    IFTBOOL(DataSizeInUINTs-ConsumedUINTs >= 1, DXC_E_GENERAL_INTERNAL_ERROR);
+    IFTBOOL(DataSizeInUINTs - ConsumedUINTs >= 1, DXC_E_GENERAL_INTERNAL_ERROR);
     unsigned NumOutputs = pData[ConsumedUINTs++];
     m_NumOutputSigScalars[StreamId] = NumOutputs;
 
     if (m_bUsesViewId) {
-      ConsumedUINTs += DeserializeOutputsDependentOnViewId(NumOutputs, 
-                                                           m_OutputsDependentOnViewId[StreamId],
-                                                           &pData[ConsumedUINTs],
-                                                           DataSizeInUINTs-ConsumedUINTs);
+      ConsumedUINTs += DeserializeOutputsDependentOnViewId(
+          NumOutputs, m_OutputsDependentOnViewId[StreamId],
+          &pData[ConsumedUINTs], DataSizeInUINTs - ConsumedUINTs);
     }
-    ConsumedUINTs += DeserializeInputsContributingToOutput(NumInputs, NumOutputs,
-                                                           m_InputsContributingToOutputs[StreamId],
-                                                           &pData[ConsumedUINTs],
-                                                           DataSizeInUINTs-ConsumedUINTs);
+    ConsumedUINTs += DeserializeInputsContributingToOutput(
+        NumInputs, NumOutputs, m_InputsContributingToOutputs[StreamId],
+        &pData[ConsumedUINTs], DataSizeInUINTs - ConsumedUINTs);
   }
 
   if (pSM->IsHS() || pSM->IsDS()) {
-    IFTBOOL(DataSizeInUINTs-ConsumedUINTs >= 1, DXC_E_GENERAL_INTERNAL_ERROR);
+    IFTBOOL(DataSizeInUINTs - ConsumedUINTs >= 1, DXC_E_GENERAL_INTERNAL_ERROR);
     unsigned NumPCs = pData[ConsumedUINTs++];
     m_NumPCSigScalars = NumPCs;
     if (pSM->IsHS()) {
       if (m_bUsesViewId) {
-        ConsumedUINTs += DeserializeOutputsDependentOnViewId(NumPCs, 
-                                                             m_PCOutputsDependentOnViewId,
-                                                             &pData[ConsumedUINTs],
-                                                             DataSizeInUINTs-ConsumedUINTs);
+        ConsumedUINTs += DeserializeOutputsDependentOnViewId(
+            NumPCs, m_PCOutputsDependentOnViewId, &pData[ConsumedUINTs],
+            DataSizeInUINTs - ConsumedUINTs);
       }
-      ConsumedUINTs += DeserializeInputsContributingToOutput(NumInputs, NumPCs,
-                                                             m_InputsContributingToPCOutputs,
-                                                             &pData[ConsumedUINTs],
-                                                             DataSizeInUINTs-ConsumedUINTs);
+      ConsumedUINTs += DeserializeInputsContributingToOutput(
+          NumInputs, NumPCs, m_InputsContributingToPCOutputs,
+          &pData[ConsumedUINTs], DataSizeInUINTs - ConsumedUINTs);
     } else {
       unsigned NumOutputs = getNumOutputSigScalars(0);
-      ConsumedUINTs += DeserializeInputsContributingToOutput(NumPCs, NumOutputs,
-                                                             m_PCInputsContributingToOutputs,
-                                                             &pData[ConsumedUINTs],
-                                                             DataSizeInUINTs-ConsumedUINTs);
+      ConsumedUINTs += DeserializeInputsContributingToOutput(
+          NumPCs, NumOutputs, m_PCInputsContributingToOutputs,
+          &pData[ConsumedUINTs], DataSizeInUINTs - ConsumedUINTs);
     }
   }
 
   DXASSERT_NOMSG(ConsumedUINTs == DataSizeInUINTs);
 }
-
-unsigned DxilViewIdState::DeserializeOutputsDependentOnViewId(unsigned NumOutputs, 
-                                                              OutputsDependentOnViewIdType &OutputsDependentOnViewId,
-                                                              const unsigned *pData, unsigned DataSize) {
-  unsigned NumOutUINTs = RoundUpToUINT(NumOutputs);
-  IFTBOOL(NumOutUINTs <= DataSize, DXC_E_GENERAL_INTERNAL_ERROR);
-
-  // Deserialize output dependence on ViewId.
-  for (unsigned i = 0; i < NumOutUINTs; i++) {
-    unsigned x = *pData++;
-    for (unsigned j = 0; j < std::min(32u, NumOutputs - 32u*i); j++) {
-      if (x & (1u << j)) {
-        OutputsDependentOnViewId[i*32 + j] = true;
-      }
-    }
-  }
-
-  return NumOutUINTs;
-}
-
-unsigned DxilViewIdState::DeserializeInputsContributingToOutput(unsigned NumInputs, unsigned NumOutputs,
-                                                                InputsContributingToOutputType &InputsContributingToOutputs,
-                                                                const unsigned *pData, unsigned DataSize) {
-  unsigned NumOutUINTs = RoundUpToUINT(NumOutputs);
-  unsigned Size = NumInputs * NumOutUINTs;
-  IFTBOOL(Size <= DataSize, DXC_E_GENERAL_INTERNAL_ERROR);
-
-  // Deserialize output dependence on inputs.
-  for (unsigned inputIdx = 0; inputIdx < NumInputs; inputIdx++) {
-    for (unsigned outputIdx = 0; outputIdx < NumOutputs; outputIdx++) {
-      unsigned w = outputIdx / 32;
-      unsigned b = outputIdx % 32;
-      if (pData[inputIdx*NumOutUINTs + w] & (1u << b)) {
-        InputsContributingToOutputs[outputIdx].insert(inputIdx);
-      }
-    }
-  }
-
-  return Size;
-}
-
-char ComputeViewIdState::ID = 0;
-
-INITIALIZE_PASS_BEGIN(ComputeViewIdState, "viewid-state",
-                "Compute information related to ViewID", true, true)
-INITIALIZE_PASS_END(ComputeViewIdState, "viewid-state",
-                "Compute information related to ViewID", true, true)
-
-ComputeViewIdState::ComputeViewIdState() : ModulePass(ID) {
-}
-
-bool ComputeViewIdState::runOnModule(Module &M) {
-  DxilModule &DxilModule = M.GetOrCreateDxilModule();
-  const ShaderModel *pSM = DxilModule.GetShaderModel();
-  if (!pSM->IsCS() && !pSM->IsLib()) {
-    DxilViewIdState &ViewIdState = DxilModule.GetViewIdState();
-    ViewIdState.Compute();
-    return true;
-  }
-  return false;
-}
-
-void ComputeViewIdState::getAnalysisUsage(AnalysisUsage &AU) const {
-  AU.setPreservesAll();
-}
-
-
-namespace llvm {
-
-ModulePass *createComputeViewIdStatePass() {
-  return new ComputeViewIdState();
-}
-
-} // end of namespace llvm

lib/HLSL/ComputeViewIdStateBuilder.cpp

@@ -0,0 +1,882 @@
+///////////////////////////////////////////////////////////////////////////////
+//                                                                           //
+// ComputeViewIdStateBuilder.cpp                                             //
+// Copyright (C) Microsoft Corporation. All rights reserved.                 //
+// This file is distributed under the University of Illinois Open Source     //
+// License. See LICENSE.TXT for details.                                     //
+//                                                                           //
+///////////////////////////////////////////////////////////////////////////////
+
+#include "dxc/HLSL/ComputeViewIdState.h"
+#include "dxc/Support/Global.h"
+#include "dxc/HLSL/DxilModule.h"
+#include "dxc/HLSL/DxilOperations.h"
+#include "dxc/HLSL/DxilInstructions.h"
+
+#include "llvm/IR/LLVMContext.h"
+#include "llvm/IR/Module.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/Operator.h"
+#include "llvm/Pass.h"
+#include "llvm/IR/LegacyPassManager.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/IR/CFG.h"
+#include "llvm/Analysis/CallGraph.h"
+
+#include <algorithm>
+
+using namespace llvm;
+using namespace llvm::legacy;
+using namespace hlsl;
+using llvm::legacy::PassManager;
+using llvm::legacy::FunctionPassManager;
+using std::vector;
+using std::unordered_set;
+using std::unordered_map;
+
+#define DXILVIEWID_DBG   0
+
+#define DEBUG_TYPE "viewid_builder"
+
+namespace {
+class DxilViewIdStateBuilder {
+  static const unsigned kNumComps = 4;
+  static const unsigned kMaxSigScalars = 32 * 4;
+
+public:
+  using OutputsDependentOnViewIdType = DxilViewIdStateData::OutputsDependentOnViewIdType;
+  using InputsContributingToOutputType = DxilViewIdStateData::InputsContributingToOutputType;
+
+  DxilViewIdStateBuilder(DxilViewIdStateData &state, DxilModule *pDxilModule)
+      : m_pModule(pDxilModule),
+        m_NumInputSigScalars(state.m_NumInputSigScalars),
+        m_NumOutputSigScalars(state.m_NumOutputSigScalars,
+                              DxilViewIdStateData::kNumStreams),
+        m_NumPCSigScalars(state.m_NumPCSigScalars),
+        m_OutputsDependentOnViewId(state.m_OutputsDependentOnViewId,
+                                   DxilViewIdStateData::kNumStreams),
+        m_PCOutputsDependentOnViewId(state.m_PCOutputsDependentOnViewId),
+        m_InputsContributingToOutputs(state.m_InputsContributingToOutputs,
+                                      DxilViewIdStateData::kNumStreams),
+        m_InputsContributingToPCOutputs(state.m_InputsContributingToPCOutputs),
+        m_PCInputsContributingToOutputs(state.m_PCInputsContributingToOutputs),
+        m_SerializedState(state.m_SerializedState),
+        m_bUsesViewId(state.m_bUsesViewId) {}
+
+  void Compute();
+
+private:
+  static const unsigned kNumStreams = 4;
+
+  DxilModule *m_pModule;
+
+  unsigned &m_NumInputSigScalars;
+  MutableArrayRef<unsigned> m_NumOutputSigScalars;
+  unsigned &m_NumPCSigScalars;
+
+  // Set of scalar outputs dependent on ViewID.
+  MutableArrayRef<OutputsDependentOnViewIdType> m_OutputsDependentOnViewId;
+  OutputsDependentOnViewIdType &m_PCOutputsDependentOnViewId;
+
+  // Set of scalar inputs contributing to computation of scalar outputs.
+  MutableArrayRef<InputsContributingToOutputType> m_InputsContributingToOutputs;
+  InputsContributingToOutputType &m_InputsContributingToPCOutputs; // HS PC only.
+  InputsContributingToOutputType &m_PCInputsContributingToOutputs; // DS only.
+
+  // Serialized form.
+  std::vector<unsigned> &m_SerializedState;
+
+  bool &m_bUsesViewId;
+
+  // Members for build ViewIdState.
+
+  // Dynamically indexed components of signature elements.
+  using DynamicallyIndexedElemsType = std::unordered_map<unsigned, unsigned>;
+  DynamicallyIndexedElemsType m_InpSigDynIdxElems;
+  DynamicallyIndexedElemsType m_OutSigDynIdxElems;
+  DynamicallyIndexedElemsType m_PCSigDynIdxElems;
+
+  // Information per entry point.
+  using FunctionSetType = std::unordered_set<llvm::Function *>;
+  using InstructionSetType = std::unordered_set<llvm::Instruction *>;
+  struct EntryInfo {
+    llvm::Function *pEntryFunc = nullptr;
+    // Sets of functions that may be reachable from an entry.
+    FunctionSetType Functions;
+    // Outputs to analyze.
+    InstructionSetType Outputs;
+    // Contributing instructions per output.
+    std::unordered_map<unsigned, InstructionSetType>
+        ContributingInstructions[kNumStreams];
+
+    void Clear();
+  };
+
+  EntryInfo m_Entry;
+  EntryInfo m_PCEntry;
+
+  // Information per function.
+  using FunctionReturnSet = std::unordered_set<llvm::ReturnInst *>;
+  struct FuncInfo {
+    FunctionReturnSet Returns;
+    ControlDependence CtrlDep;
+    std::unique_ptr<llvm::DominatorTreeBase<llvm::BasicBlock>> pDomTree;
+    void Clear();
+  };
+
+  std::unordered_map<llvm::Function *, std::unique_ptr<FuncInfo>> m_FuncInfo;
+
+  // Cache of decls (global/alloca) reaching a pointer value.
+  using ValueSetType = std::unordered_set<llvm::Value *>;
+  std::unordered_map<llvm::Value *, ValueSetType> m_ReachingDeclsCache;
+  // Cache of stores for each decl.
+  std::unordered_map<llvm::Value *, ValueSetType> m_StoresPerDeclCache;
+
+
+  void Clear();
+  void DetermineMaxPackedLocation(DxilSignature &DxilSig, unsigned *pMaxSigLoc,
+                                  unsigned NumStreams);
+  void ComputeReachableFunctionsRec(llvm::CallGraph &CG,
+                                    llvm::CallGraphNode *pNode,
+                                    FunctionSetType &FuncSet);
+  void AnalyzeFunctions(EntryInfo &Entry);
+  void CollectValuesContributingToOutputs(EntryInfo &Entry);
+  void CollectValuesContributingToOutputRec(
+      EntryInfo &Entry, llvm::Value *pContributingValue,
+      InstructionSetType &ContributingInstructions);
+  void CollectPhiCFValuesContributingToOutputRec(
+      llvm::PHINode *pPhi, EntryInfo &Entry,
+      InstructionSetType &ContributingInstructions);
+  const ValueSetType &CollectReachingDecls(llvm::Value *pValue);
+  void CollectReachingDeclsRec(llvm::Value *pValue, ValueSetType &ReachingDecls,
+                               ValueSetType &Visited);
+  const ValueSetType &CollectStores(llvm::Value *pValue);
+  void CollectStoresRec(llvm::Value *pValue, ValueSetType &Stores,
+                        ValueSetType &Visited);
+  void UpdateDynamicIndexUsageState() const;
+  void
+  CreateViewIdSets(const std::unordered_map<unsigned, InstructionSetType>
+                       &ContributingInstructions,
+                   OutputsDependentOnViewIdType &OutputsDependentOnViewId,
+                   InputsContributingToOutputType &InputsContributingToOutputs,
+                   bool bPC);
+
+  void UpdateDynamicIndexUsageStateForSig(
+      DxilSignature &Sig, const DynamicallyIndexedElemsType &DynIdxElems) const;
+  unsigned GetLinearIndex(DxilSignatureElement &SigElem, int row,
+                          unsigned col) const;
+
+};
+} // namespace
+
+void DxilViewIdStateBuilder::Compute() {
+  Clear();
+
+  const ShaderModel *pSM = m_pModule->GetShaderModel();
+  m_bUsesViewId = m_pModule->m_ShaderFlags.GetViewID();
+
+  // 1. Traverse signature MD to determine max packed location.
+  DetermineMaxPackedLocation(m_pModule->GetInputSignature(), &m_NumInputSigScalars, 1);
+  DetermineMaxPackedLocation(m_pModule->GetOutputSignature(), &m_NumOutputSigScalars[0], pSM->IsGS() ? kNumStreams : 1);
+  DetermineMaxPackedLocation(m_pModule->GetPatchConstantSignature(), &m_NumPCSigScalars, 1);
+
+  // 2. Collect sets of functions reachable from main and pc entries.
+  CallGraphAnalysis CGA;
+  CallGraph CG = CGA.run(m_pModule->GetModule());
+  m_Entry.pEntryFunc = m_pModule->GetEntryFunction();
+  m_PCEntry.pEntryFunc = m_pModule->GetPatchConstantFunction();
+  ComputeReachableFunctionsRec(CG, CG[m_Entry.pEntryFunc], m_Entry.Functions);
+  if (m_PCEntry.pEntryFunc) {
+    DXASSERT_NOMSG(pSM->IsHS());
+    ComputeReachableFunctionsRec(CG, CG[m_PCEntry.pEntryFunc], m_PCEntry.Functions);
+  }
+
+  // 3. Determine shape components that are dynamically accesses and collect all sig outputs.
+  AnalyzeFunctions(m_Entry);
+  if (m_PCEntry.pEntryFunc) {
+    AnalyzeFunctions(m_PCEntry);
+  }
+
+  // 4. Collect sets of values contributing to outputs.
+  CollectValuesContributingToOutputs(m_Entry);
+  if (m_PCEntry.pEntryFunc) {
+    CollectValuesContributingToOutputs(m_PCEntry);
+  }
+
+  // 5. Construct dependency sets.
+  for (unsigned StreamId = 0; StreamId < (pSM->IsGS() ? kNumStreams : 1u); StreamId++) {
+    CreateViewIdSets(m_Entry.ContributingInstructions[StreamId],
+                     m_OutputsDependentOnViewId[StreamId],
+                     m_InputsContributingToOutputs[StreamId], false);
+  }
+  if (pSM->IsHS()) {
+    CreateViewIdSets(m_PCEntry.ContributingInstructions[0],
+                     m_PCOutputsDependentOnViewId,
+                     m_InputsContributingToPCOutputs, true);
+  } else if (pSM->IsDS()) {
+    OutputsDependentOnViewIdType OutputsDependentOnViewId;
+    CreateViewIdSets(m_Entry.ContributingInstructions[0],
+                     OutputsDependentOnViewId,
+                     m_PCInputsContributingToOutputs, true);
+    DXASSERT_NOMSG(OutputsDependentOnViewId == m_OutputsDependentOnViewId[0]);
+  }
+
+  // 6. Update dynamically indexed input/output component masks.
+  UpdateDynamicIndexUsageState();
+
+#if DXILVIEWID_DBG
+  PrintSets(dbgs());
+#endif
+}
+
+void DxilViewIdStateBuilder::Clear() {
+  m_bUsesViewId = false;
+  m_NumInputSigScalars  = 0;
+  for (unsigned i = 0; i < kNumStreams; i++) {
+    m_NumOutputSigScalars[i] = 0;
+    m_OutputsDependentOnViewId[i].reset();
+    m_InputsContributingToOutputs[i].clear();
+  }
+  m_NumPCSigScalars     = 0;
+  m_InpSigDynIdxElems.clear();
+  m_OutSigDynIdxElems.clear();
+  m_PCSigDynIdxElems.clear();
+  m_PCOutputsDependentOnViewId.reset();
+  m_InputsContributingToPCOutputs.clear();
+  m_PCInputsContributingToOutputs.clear();
+  m_Entry.Clear();
+  m_PCEntry.Clear();
+  m_FuncInfo.clear();
+  m_ReachingDeclsCache.clear();
+  m_SerializedState.clear();
+}
+
+void DxilViewIdStateBuilder::EntryInfo::Clear() {
+  pEntryFunc = nullptr;
+  Functions.clear();
+  Outputs.clear();
+  for (unsigned i = 0; i < kNumStreams; i++)
+    ContributingInstructions[i].clear();
+}
+
+void DxilViewIdStateBuilder::FuncInfo::Clear() {
+  Returns.clear();
+  CtrlDep.Clear();
+  pDomTree.reset();
+}
+
+void DxilViewIdStateBuilder::DetermineMaxPackedLocation(DxilSignature &DxilSig,
+                                                 unsigned *pMaxSigLoc,
+                                                 unsigned NumStreams) {
+  DXASSERT_NOMSG(NumStreams == 1 || NumStreams == kNumStreams);
+
+  for (unsigned i = 0; i < NumStreams; i++) {
+    pMaxSigLoc[i] = 0;
+  }
+
+  for (auto &E : DxilSig.GetElements()) {
+    if (E->GetStartRow() == Semantic::kUndefinedRow) continue;
+
+    unsigned StreamId = E->GetOutputStream();
+    unsigned endLoc = GetLinearIndex(*E, E->GetRows() - 1, E->GetCols() - 1);
+    pMaxSigLoc[StreamId] = std::max(pMaxSigLoc[StreamId], endLoc + 1);
+    E->GetCols();
+  }
+}
+
+void DxilViewIdStateBuilder::ComputeReachableFunctionsRec(CallGraph &CG, CallGraphNode *pNode, FunctionSetType &FuncSet) {
+  Function *F = pNode->getFunction();
+  // Accumulate only functions with bodies.
+  if (F->empty()) return;
+  auto itIns = FuncSet.emplace(F);
+  DXASSERT_NOMSG(itIns.second);
+  (void)itIns;
+  for (auto it = pNode->begin(), itEnd = pNode->end(); it != itEnd; ++it) {
+    CallGraphNode *pSuccNode = it->second;
+    ComputeReachableFunctionsRec(CG, pSuccNode, FuncSet);
+  }
+}
+
+static bool GetUnsignedVal(Value *V, uint32_t *pValue) {
+  ConstantInt *CI = dyn_cast<ConstantInt>(V);
+  if (!CI) return false;
+  uint64_t u = CI->getZExtValue();
+  if (u > UINT32_MAX) return false;
+  *pValue = (uint32_t)u;
+  return true;
+}
+
+void DxilViewIdStateBuilder::AnalyzeFunctions(EntryInfo &Entry) {
+  for (auto *F : Entry.Functions) {
+    DXASSERT_NOMSG(!F->empty());
+
+    auto itFI = m_FuncInfo.find(F);
+    FuncInfo *pFuncInfo = nullptr;
+    if (itFI != m_FuncInfo.end()) {
+      pFuncInfo = itFI->second.get();
+    } else {
+      m_FuncInfo[F] = make_unique<FuncInfo>();
+      pFuncInfo = m_FuncInfo[F].get();
+    }
+
+    for (auto itBB = F->begin(), endBB = F->end(); itBB != endBB; ++itBB) {
+      BasicBlock *BB = itBB;
+
+      for (auto itInst = BB->begin(), endInst = BB->end(); itInst != endInst; ++itInst) {
+        if (ReturnInst *RI = dyn_cast<ReturnInst>(itInst)) {
+          pFuncInfo->Returns.emplace(RI);
+          continue;
+        }
+
+        CallInst *CI = dyn_cast<CallInst>(itInst);
+        if (!CI) continue;
+
+        DynamicallyIndexedElemsType *pDynIdxElems = nullptr;
+        int row = Semantic::kUndefinedRow;
+        unsigned id, col;
+        if (DxilInst_LoadInput LI = DxilInst_LoadInput(CI)) {
+          pDynIdxElems = &m_InpSigDynIdxElems;
+          IFTBOOL(GetUnsignedVal(LI.get_inputSigId(), &id), DXC_E_GENERAL_INTERNAL_ERROR);
+          GetUnsignedVal(LI.get_rowIndex(), (uint32_t*)&row);
+          IFTBOOL(GetUnsignedVal(LI.get_colIndex(), &col), DXC_E_GENERAL_INTERNAL_ERROR);
+        } else if (DxilInst_StoreOutput SO = DxilInst_StoreOutput(CI)) {
+          pDynIdxElems = &m_OutSigDynIdxElems;
+          IFTBOOL(GetUnsignedVal(SO.get_outputSigId(), &id), DXC_E_GENERAL_INTERNAL_ERROR);
+          GetUnsignedVal(SO.get_rowIndex(), (uint32_t*)&row);
+          IFTBOOL(GetUnsignedVal(SO.get_colIndex(), &col), DXC_E_GENERAL_INTERNAL_ERROR);
+          Entry.Outputs.emplace(CI);
+        } else if (DxilInst_LoadPatchConstant LPC = DxilInst_LoadPatchConstant(CI)) {
+          if (m_pModule->GetShaderModel()->IsDS()) {
+            pDynIdxElems = &m_PCSigDynIdxElems;
+            IFTBOOL(GetUnsignedVal(LPC.get_inputSigId(), &id), DXC_E_GENERAL_INTERNAL_ERROR);
+            GetUnsignedVal(LPC.get_row(), (uint32_t*)&row);
+            IFTBOOL(GetUnsignedVal(LPC.get_col(), &col), DXC_E_GENERAL_INTERNAL_ERROR);
+          } else {
+            // Do nothing. This is an internal helper function for DXBC-2-DXIL converter.
+            DXASSERT_NOMSG(m_pModule->GetShaderModel()->IsHS());
+          }
+        } else if (DxilInst_StorePatchConstant SPC = DxilInst_StorePatchConstant(CI)) {
+          pDynIdxElems = &m_PCSigDynIdxElems;
+          IFTBOOL(GetUnsignedVal(SPC.get_outputSigID(), &id), DXC_E_GENERAL_INTERNAL_ERROR);
+          GetUnsignedVal(SPC.get_row(), (uint32_t*)&row);
+          IFTBOOL(GetUnsignedVal(SPC.get_col(), &col), DXC_E_GENERAL_INTERNAL_ERROR);
+          Entry.Outputs.emplace(CI);
+        } else if (DxilInst_LoadOutputControlPoint LOCP = DxilInst_LoadOutputControlPoint(CI)) {
+          if (m_pModule->GetShaderModel()->IsDS()) {
+            pDynIdxElems = &m_InpSigDynIdxElems;
+            IFTBOOL(GetUnsignedVal(LOCP.get_inputSigId(), &id), DXC_E_GENERAL_INTERNAL_ERROR);
+            GetUnsignedVal(LOCP.get_row(), (uint32_t*)&row);
+            IFTBOOL(GetUnsignedVal(LOCP.get_col(), &col), DXC_E_GENERAL_INTERNAL_ERROR);
+          } else if (m_pModule->GetShaderModel()->IsHS()) {
+            // Do nothings, as the information has been captured by the output signature of CP entry.
+          } else {
+            DXASSERT_NOMSG(false);
+          }
+        } else {
+          continue;
+        }
+
+        // Record dynamic index usage.
+        if (pDynIdxElems && row == Semantic::kUndefinedRow) {
+          (*pDynIdxElems)[id] |= (1 << col);
+        }
+      }
+    }
+
+    // Compute dominator relation.
+    pFuncInfo->pDomTree = make_unique<DominatorTreeBase<BasicBlock> >(false);
+    pFuncInfo->pDomTree->recalculate(*F);
+#if DXILVIEWID_DBG
+    pFuncInfo->pDomTree->print(dbgs());
+#endif
+
+    // Compute postdominator relation.
+    DominatorTreeBase<BasicBlock> PDR(true);
+    PDR.recalculate(*F);
+#if DXILVIEWID_DBG
+    PDR.print(dbgs());
+#endif
+    // Compute control dependence.
+    pFuncInfo->CtrlDep.Compute(F, PDR);
+#if DXILVIEWID_DBG
+    pFuncInfo->CtrlDep.print(dbgs());
+#endif
+  }
+}
+
+void DxilViewIdStateBuilder::CollectValuesContributingToOutputs(EntryInfo &Entry) {
+  for (auto *CI : Entry.Outputs) {  // CI = call instruction
+    DxilSignature *pDxilSig = nullptr;
+    Value *pContributingValue = nullptr;
+    unsigned id = (unsigned)-1;
+    int startRow = Semantic::kUndefinedRow, endRow = Semantic::kUndefinedRow;
+    unsigned col = (unsigned)-1;
+    if (DxilInst_StoreOutput SO = DxilInst_StoreOutput(CI)) {
+      pDxilSig = &m_pModule->GetOutputSignature();
+      pContributingValue = SO.get_value();
+      GetUnsignedVal(SO.get_outputSigId(), &id);
+      GetUnsignedVal(SO.get_colIndex(), &col);
+      GetUnsignedVal(SO.get_rowIndex(), (uint32_t*)&startRow);
+    } else if (DxilInst_StorePatchConstant SPC = DxilInst_StorePatchConstant(CI)) {
+      pDxilSig = &m_pModule->GetPatchConstantSignature();
+      pContributingValue = SPC.get_value();
+      GetUnsignedVal(SPC.get_outputSigID(), &id);
+      GetUnsignedVal(SPC.get_row(), (uint32_t*)&startRow);
+      GetUnsignedVal(SPC.get_col(), &col);
+    } else {
+      IFT(DXC_E_GENERAL_INTERNAL_ERROR);
+    }
+
+    DxilSignatureElement &SigElem = pDxilSig->GetElement(id);
+    if (!SigElem.IsAllocated())
+      continue;
+
+    unsigned StreamId = SigElem.GetOutputStream();
+
+    if (startRow != Semantic::kUndefinedRow) {
+      endRow = startRow;
+    } else {
+      // The entire column is affected by value.
+      DXASSERT_NOMSG(SigElem.GetID() == id && SigElem.GetStartRow() != Semantic::kUndefinedRow);
+      startRow = 0;
+      endRow = SigElem.GetRows() - 1;
+    }
+
+    InstructionSetType ContributingInstructionsAllRows;
+    InstructionSetType *pContributingInstructions = &ContributingInstructionsAllRows;
+    if (startRow == endRow) {
+      // Scalar or indexable with known index.
+      unsigned index = GetLinearIndex(SigElem, startRow, col);
+      pContributingInstructions = &Entry.ContributingInstructions[StreamId][index];
+    }
+
+    CollectValuesContributingToOutputRec(Entry, pContributingValue, *pContributingInstructions);
+
+    // Handle control dependence of this instruction BB.
+    BasicBlock *pBB = CI->getParent();
+    Function *F = pBB->getParent();
+    FuncInfo *pFuncInfo = m_FuncInfo[F].get();
+    const BasicBlockSet &CtrlDepSet = pFuncInfo->CtrlDep.GetCDBlocks(pBB);
+    for (BasicBlock *B : CtrlDepSet) {
+      CollectValuesContributingToOutputRec(Entry, B->getTerminator(), *pContributingInstructions);
+    }
+
+    if (pContributingInstructions == &ContributingInstructionsAllRows) {
+      // Write dynamically indexed output contributions to all rows.
+      for (int row = startRow; row <= endRow; row++) {
+        unsigned index = GetLinearIndex(SigElem, row, col);
+        Entry.ContributingInstructions[StreamId][index].insert(ContributingInstructionsAllRows.begin(), ContributingInstructionsAllRows.end());
+      }
+    }
+  }
+}
+
+void DxilViewIdStateBuilder::CollectValuesContributingToOutputRec(EntryInfo &Entry,
+                                                           Value *pContributingValue,
+                                                           InstructionSetType &ContributingInstructions) {
+  if (dyn_cast<Argument>(pContributingValue)) {
+    // This must be a leftover signature argument of an entry function.
+    DXASSERT_NOMSG(Entry.pEntryFunc == m_pModule->GetEntryFunction() ||
+                   Entry.pEntryFunc == m_pModule->GetPatchConstantFunction());
+    return;
+  }
+
+  Instruction *pContributingInst = dyn_cast<Instruction>(pContributingValue);
+  if (pContributingInst == nullptr) {
+    // Can be literal constant, global decl, branch target.
+    DXASSERT_NOMSG(isa<Constant>(pContributingValue) || isa<BasicBlock>(pContributingValue));
+    return;
+  }
+
+  auto itInst = ContributingInstructions.emplace(pContributingInst);
+  // Already visited instruction.
+  if (!itInst.second) return;
+
+  // Handle special cases.
+  if (PHINode *phi = dyn_cast<PHINode>(pContributingInst)) {
+    CollectPhiCFValuesContributingToOutputRec(phi, Entry, ContributingInstructions);
+  } else if (isa<LoadInst>(pContributingInst) || 
+             isa<AtomicCmpXchgInst>(pContributingInst) ||
+             isa<AtomicRMWInst>(pContributingInst)) {
+    Value *pPtrValue = pContributingInst->getOperand(0);
+    DXASSERT_NOMSG(pPtrValue->getType()->isPointerTy());
+    const ValueSetType &ReachingDecls = CollectReachingDecls(pPtrValue);
+    DXASSERT_NOMSG(ReachingDecls.size() > 0);
+    for (Value *pDeclValue : ReachingDecls) {
+      const ValueSetType &Stores = CollectStores(pDeclValue);
+      for (Value *V : Stores) {
+        CollectValuesContributingToOutputRec(Entry, V, ContributingInstructions);
+      }
+    }
+  } else if (CallInst *CI = dyn_cast<CallInst>(pContributingInst)) {
+    if (!hlsl::OP::IsDxilOpFuncCallInst(CI)) {
+      Function *F = CI->getCalledFunction();
+      if (!F->empty()) {
+        // Return value of a user function.
+        if (Entry.Functions.find(F) != Entry.Functions.end()) {
+          const FuncInfo &FI = *m_FuncInfo[F];
+          for (ReturnInst *pRetInst : FI.Returns) {
+            CollectValuesContributingToOutputRec(Entry, pRetInst, ContributingInstructions);
+          }
+        }
+      }
+    }
+  }
+
+  // Handle instruction inputs.
+  unsigned NumOps = pContributingInst->getNumOperands();
+  for (unsigned i = 0; i < NumOps; i++) {
+    Value *O = pContributingInst->getOperand(i);
+    CollectValuesContributingToOutputRec(Entry, O, ContributingInstructions);
+  }
+
+  // Handle control dependence of this instruction BB.
+  BasicBlock *pBB = pContributingInst->getParent();
+  Function *F = pBB->getParent();
+  FuncInfo *pFuncInfo = m_FuncInfo[F].get();
+  const BasicBlockSet &CtrlDepSet = pFuncInfo->CtrlDep.GetCDBlocks(pBB);
+  for (BasicBlock *B : CtrlDepSet) {
+    CollectValuesContributingToOutputRec(Entry, B->getTerminator(), ContributingInstructions);
+  }
+}
+
+// Only process control-dependent basic blocks for constant operands of the phi-function.
+// An obvious "definition" point for a constant operand is the predecessor along corresponding edge.
+// However, this may be too conservative and, as such, pick up extra control dependent BBs.
+// A better "definition" point is the highest dominator where it is still legal to "insert" constant assignment.
+// In this context, "legal" means that only one value "leaves" the dominator and reaches Phi.
+void DxilViewIdStateBuilder::CollectPhiCFValuesContributingToOutputRec(PHINode *pPhi,
+                                                                EntryInfo &Entry,
+                                                                InstructionSetType &ContributingInstructions) {
+  Function *F = pPhi->getParent()->getParent();
+  FuncInfo *pFuncInfo = m_FuncInfo[F].get();
+  unordered_map<DomTreeNodeBase<BasicBlock> *, Value *> DomTreeMarkers;
+
+  // Mark predecessors of each value, so that there is a legal "definition" point.
+  for (unsigned i = 0; i < pPhi->getNumOperands(); i++) {
+    Value *pValue = pPhi->getIncomingValue(i);
+    BasicBlock *pBB = pPhi->getIncomingBlock(i);
+    DomTreeNodeBase<BasicBlock> *pDomNode = pFuncInfo->pDomTree->getNode(pBB);
+    auto it = DomTreeMarkers.emplace(pDomNode, pValue);
+    DXASSERT_NOMSG(it.second || it.first->second == pValue); (void)it;
+  }
+  // Mark the dominator tree with "definition" values, walking up to the parent.
+  for (unsigned i = 0; i < pPhi->getNumOperands(); i++) {
+    Value *pValue = pPhi->getIncomingValue(i);
+    BasicBlock *pDefBB = &F->getEntryBlock();
+    if (Instruction *pDefInst = dyn_cast<Instruction>(pValue)) {
+      pDefBB = pDefInst->getParent();
+    }
+
+    BasicBlock *pBB = pPhi->getIncomingBlock(i);
+    if (pBB == pDefBB) {
+      continue; // we already handled the predecessor.
+    }
+    DomTreeNodeBase<BasicBlock> *pDomNode = pFuncInfo->pDomTree->getNode(pBB);
+    pDomNode = pDomNode->getIDom();
+    while (pDomNode) {
+      auto it = DomTreeMarkers.emplace(pDomNode, pValue);
+      if (!it.second) {
+        if (it.first->second != pValue && it.first->second != nullptr) {
+          if (!isa<Constant>(it.first->second) || !isa<Constant>(pValue)) {
+            // Unless both are different constants, mark the "definition" point as illegal.
+            it.first->second = nullptr;
+            // If both are constants, leave the marker of the first one.
+          }
+        }
+        break;
+      }
+
+      // Do not go higher than a legal definition point.
+      pBB = pDomNode->getBlock();
+      if (pBB == pDefBB)
+        break;
+
+      pDomNode = pDomNode->getIDom();
+    }
+  }
+
+  // Handle control dependence for Constant arguments of Phi.
+  for (unsigned i = 0; i < pPhi->getNumOperands(); i++) {
+    Value *pValue = pPhi->getIncomingValue(i);
+    if (!isa<Constant>(pValue))
+      continue;
+
+    // Determine the higher legal "definition" point.
+    BasicBlock *pBB = pPhi->getIncomingBlock(i);
+    DomTreeNodeBase<BasicBlock> *pDomNode = pFuncInfo->pDomTree->getNode(pBB);
+    DomTreeNodeBase<BasicBlock> *pDefDomNode = pDomNode;
+    while (pDomNode) {
+      auto it = DomTreeMarkers.find(pDomNode);
+      DXASSERT_NOMSG(it != DomTreeMarkers.end());
+      if (it->second != pValue) {
+        DXASSERT_NOMSG(it->second == nullptr || isa<Constant>(it->second));
+        break;
+      }
+
+      pDefDomNode = pDomNode;
+      pDomNode = pDomNode->getIDom();
+    }
+
+    // Handle control dependence of this constant argument highest legal "definition" point.
+    pBB = pDefDomNode->getBlock();
+    const BasicBlockSet &CtrlDepSet = pFuncInfo->CtrlDep.GetCDBlocks(pBB);
+    for (BasicBlock *B : CtrlDepSet) {
+      CollectValuesContributingToOutputRec(Entry, B->getTerminator(), ContributingInstructions);
+    }
+  }
+}
+
+const DxilViewIdStateBuilder::ValueSetType &DxilViewIdStateBuilder::CollectReachingDecls(Value *pValue) {
+  auto it = m_ReachingDeclsCache.emplace(pValue, ValueSetType());
+  if (it.second) {
+    // We have not seen this value before.
+    ValueSetType Visited;
+    CollectReachingDeclsRec(pValue, it.first->second, Visited);
+  }
+  return it.first->second;
+}
+
+void DxilViewIdStateBuilder::CollectReachingDeclsRec(Value *pValue, ValueSetType &ReachingDecls, ValueSetType &Visited) {
+  if (Visited.find(pValue) != Visited.end())
+    return;
+
+  bool bInitialValue = Visited.size() == 0;
+  Visited.emplace(pValue);
+
+  if (!bInitialValue) {
+    auto it = m_ReachingDeclsCache.find(pValue);
+    if (it != m_ReachingDeclsCache.end()) {
+      ReachingDecls.insert(it->second.begin(), it->second.end());
+      return;
+    }
+  }
+
+  if (dyn_cast<GlobalVariable>(pValue)) {
+    ReachingDecls.emplace(pValue);
+    return;
+  }
+
+  if (GetElementPtrInst *pGepInst = dyn_cast<GetElementPtrInst>(pValue)) {
+    Value *pPtrValue = pGepInst->getPointerOperand();
+    CollectReachingDeclsRec(pPtrValue, ReachingDecls, Visited);
+  } else if (GEPOperator *pGepOp = dyn_cast<GEPOperator>(pValue)) {
+    Value *pPtrValue = pGepOp->getPointerOperand();
+    CollectReachingDeclsRec(pPtrValue, ReachingDecls, Visited);
+  } else if (dyn_cast<AllocaInst>(pValue)) {
+    ReachingDecls.emplace(pValue);
+  } else if (PHINode *phi = dyn_cast<PHINode>(pValue)) {
+    for (Value *pPtrValue : phi->operands()) {
+      CollectReachingDeclsRec(pPtrValue, ReachingDecls, Visited);
+    }
+  } else if (SelectInst *SelI = dyn_cast<SelectInst>(pValue)) {
+    CollectReachingDeclsRec(SelI->getTrueValue(), ReachingDecls, Visited);
+    CollectReachingDeclsRec(SelI->getFalseValue(), ReachingDecls, Visited);
+  } else if (dyn_cast<Argument>(pValue)) {
+    ReachingDecls.emplace(pValue);
+  } else {
+    IFT(DXC_E_GENERAL_INTERNAL_ERROR);
+  }
+}
+
+const DxilViewIdStateBuilder::ValueSetType &DxilViewIdStateBuilder::CollectStores(llvm::Value *pValue) {
+  auto it = m_StoresPerDeclCache.emplace(pValue, ValueSetType());
+  if (it.second) {
+    // We have not seen this value before.
+    ValueSetType Visited;
+    CollectStoresRec(pValue, it.first->second, Visited);
+  }
+  return it.first->second;
+}
+
+void DxilViewIdStateBuilder::CollectStoresRec(llvm::Value *pValue, ValueSetType &Stores, ValueSetType &Visited) {
+  if (Visited.find(pValue) != Visited.end())
+    return;
+
+  bool bInitialValue = Visited.size() == 0;
+  Visited.emplace(pValue);
+
+  if (!bInitialValue) {
+    auto it = m_StoresPerDeclCache.find(pValue);
+    if (it != m_StoresPerDeclCache.end()) {
+      Stores.insert(it->second.begin(), it->second.end());
+      return;
+    }
+  }
+
+  if (isa<LoadInst>(pValue)) {
+    return;
+  } else if (isa<StoreInst>(pValue) ||
+             isa<AtomicCmpXchgInst>(pValue) ||
+             isa<AtomicRMWInst>(pValue)) {
+    Stores.emplace(pValue);
+    return;
+  }
+
+  for (auto *U : pValue->users()) {
+    CollectStoresRec(U, Stores, Visited);
+  }
+}
+
+void DxilViewIdStateBuilder::CreateViewIdSets(const std::unordered_map<unsigned, InstructionSetType> &ContributingInstructions, 
+                                       OutputsDependentOnViewIdType &OutputsDependentOnViewId,
+                                       InputsContributingToOutputType &InputsContributingToOutputs,
+                                       bool bPC) {
+  const ShaderModel *pSM = m_pModule->GetShaderModel();
+
+  for (auto &itOut : ContributingInstructions) {
+    unsigned outIdx = itOut.first;
+    for (Instruction *pInst : itOut.second) {
+      // Set output dependence on ViewId.
+      if (DxilInst_ViewID VID = DxilInst_ViewID(pInst)) {
+        DXASSERT(m_bUsesViewId, "otherwise, DxilModule flag not set properly");
+        OutputsDependentOnViewId[outIdx] = true;
+        continue;
+      }
+
+      // Start setting output dependence on inputs.
+      DxilSignatureElement *pSigElem = nullptr;
+      bool bLoadOutputCPInHS = false;
+      unsigned inpId = (unsigned)-1;
+      int startRow = Semantic::kUndefinedRow, endRow = Semantic::kUndefinedRow;
+      unsigned col = (unsigned)-1;
+      if (DxilInst_LoadInput LI = DxilInst_LoadInput(pInst)) {
+        GetUnsignedVal(LI.get_inputSigId(), &inpId);
+        GetUnsignedVal(LI.get_colIndex(), &col);
+        GetUnsignedVal(LI.get_rowIndex(), (uint32_t*)&startRow);
+        pSigElem = &m_pModule->GetInputSignature().GetElement(inpId);
+        if (pSM->IsDS() && bPC) {
+          pSigElem = nullptr;
+        }
+      } else if (DxilInst_LoadOutputControlPoint LOCP = DxilInst_LoadOutputControlPoint(pInst)) {
+        GetUnsignedVal(LOCP.get_inputSigId(), &inpId);
+        GetUnsignedVal(LOCP.get_col(), &col);
+        GetUnsignedVal(LOCP.get_row(), (uint32_t*)&startRow);
+        if (pSM->IsHS()) {
+          pSigElem = &m_pModule->GetOutputSignature().GetElement(inpId);
+          bLoadOutputCPInHS = true;
+        } else if (pSM->IsDS()) {
+          if (!bPC) {
+            pSigElem = &m_pModule->GetInputSignature().GetElement(inpId);
+          }
+        } else {
+          DXASSERT_NOMSG(false);
+        }
+      } else if (DxilInst_LoadPatchConstant LPC = DxilInst_LoadPatchConstant(pInst)) {
+        if (pSM->IsDS() && bPC) {
+          GetUnsignedVal(LPC.get_inputSigId(), &inpId);
+          GetUnsignedVal(LPC.get_col(), &col);
+          GetUnsignedVal(LPC.get_row(), (uint32_t*)&startRow);
+          pSigElem = &m_pModule->GetPatchConstantSignature().GetElement(inpId);
+        }
+      } else {
+        continue;
+      }
+
+      // Finalize setting output dependence on inputs.
+      if (pSigElem && pSigElem->IsAllocated()) {
+        if (startRow != Semantic::kUndefinedRow) {
+          endRow = startRow;
+        } else {
+          // The entire column contributes to output.
+          startRow = 0;
+          endRow = pSigElem->GetRows() - 1;
+        }
+
+        auto &ContributingInputs = InputsContributingToOutputs[outIdx];
+        for (int row = startRow; row <= endRow; row++) {
+          unsigned index = GetLinearIndex(*pSigElem, row, col);
+          if (!bLoadOutputCPInHS) {
+            ContributingInputs.emplace(index);
+          } else {
+            // This HS patch-constant output depends on an input value of LoadOutputControlPoint
+            // that is the output value of the HS main (control-point) function.
+            // Transitively update this (patch-constant) output dependence on main (control-point) output.
+            DXASSERT_NOMSG(&OutputsDependentOnViewId == &m_PCOutputsDependentOnViewId);
+            OutputsDependentOnViewId[outIdx] = OutputsDependentOnViewId[outIdx] || m_OutputsDependentOnViewId[0][index];
+
+            const auto it = m_InputsContributingToOutputs[0].find(index);
+            if (it != m_InputsContributingToOutputs[0].end()) {
+              const std::set<unsigned> &LoadOutputCPInputsContributingToOutputs = it->second;
+              ContributingInputs.insert(LoadOutputCPInputsContributingToOutputs.begin(),
+                                        LoadOutputCPInputsContributingToOutputs.end());
+            }
+          }
+        }
+      }
+    }
+  }
+}
+
+unsigned DxilViewIdStateBuilder::GetLinearIndex(DxilSignatureElement &SigElem, int row, unsigned col) const {
+  DXASSERT_NOMSG(row >= 0 && col < kNumComps && SigElem.GetStartRow() != Semantic::kUndefinedRow);
+  unsigned idx = (((unsigned)row) + SigElem.GetStartRow())*kNumComps + col + SigElem.GetStartCol();
+  DXASSERT_NOMSG(idx < kMaxSigScalars);
+  return idx;
+}
+
+void DxilViewIdStateBuilder::UpdateDynamicIndexUsageState() const {
+  UpdateDynamicIndexUsageStateForSig(m_pModule->GetInputSignature(), m_InpSigDynIdxElems);
+  UpdateDynamicIndexUsageStateForSig(m_pModule->GetOutputSignature(), m_OutSigDynIdxElems);
+  UpdateDynamicIndexUsageStateForSig(m_pModule->GetPatchConstantSignature(), m_PCSigDynIdxElems);
+}
+
+void DxilViewIdStateBuilder::UpdateDynamicIndexUsageStateForSig(DxilSignature &Sig,
+                                                         const DynamicallyIndexedElemsType &DynIdxElems) const {
+  for (auto it : DynIdxElems) {
+    unsigned id = it.first;
+    unsigned mask = it.second;
+    DxilSignatureElement &E = Sig.GetElement(id);
+    E.SetDynIdxCompMask(mask);
+  }
+}
+
+
+
+namespace {
+class ComputeViewIdState : public ModulePass {
+public:
+  static char ID; // Pass ID, replacement for typeid
+
+  ComputeViewIdState();
+
+  bool runOnModule(Module &M) override;
+
+  void getAnalysisUsage(AnalysisUsage &AU) const override;
+};
+} // namespace
+
+char ComputeViewIdState::ID = 0;
+
+INITIALIZE_PASS_BEGIN(ComputeViewIdState, "viewid-state",
+                "Compute information related to ViewID", true, true)
+INITIALIZE_PASS_END(ComputeViewIdState, "viewid-state",
+                "Compute information related to ViewID", true, true)
+
+ComputeViewIdState::ComputeViewIdState() : ModulePass(ID) {
+}
+
+bool ComputeViewIdState::runOnModule(Module &M) {
+  DxilModule &DxilModule = M.GetOrCreateDxilModule();
+  const ShaderModel *pSM = DxilModule.GetShaderModel();
+  if (!pSM->IsCS() && !pSM->IsLib()) {
+    DxilViewIdState &ViewIdState = DxilModule.GetViewIdState();
+    DxilViewIdStateBuilder Builder(ViewIdState, &DxilModule);
+    Builder.Compute();
+    return true;
+  }
+  return false;
+}
+
+void ComputeViewIdState::getAnalysisUsage(AnalysisUsage &AU) const {
+  AU.setPreservesAll();
+}
+
+
+namespace llvm {
+
+ModulePass *createComputeViewIdStatePass() {
+  return new ComputeViewIdState();
+}
+
+} // end of namespace llvm

lib/HLSL/DxilModule.cpp

@@ -1373,8 +1373,6 @@ MDTuple *DxilModule::EmitDxilResources() {
 
 void DxilModule::ReEmitDxilResources() {
   ClearDxilMetadata(*m_pModule);
-  if (!m_pSM->IsCS() && !m_pSM->IsLib())
-    m_pViewIdState->Compute();
   EmitDxilMetadata();
 }