Update APIs that return a pair of iterators to return an iterator_range instead.

Convert uses of those APIs into ranged for loops. NFC.

llvm-svn: 228404

15 files changed, 98 insertions, 143 deletions

diff --git a/clang/lib/AST/CXXInheritance.cpp b/clang/lib/AST/CXXInheritance.cpp
index 6e80ee7c28a..3011e0cdd97 100644
--- a/clang/lib/AST/CXXInheritance.cpp
+++ b/clang/lib/AST/CXXInheritance.cpp
@@ -569,18 +569,14 @@ void FinalOverriderCollector::Collect(const CXXRecordDecl *RD,
     // overrider. To do so, we dig down to the original virtual
     // functions using data recursion and update all of the methods it
     // overrides.
-    typedef std::pair<CXXMethodDecl::method_iterator, 
-                      CXXMethodDecl::method_iterator> OverriddenMethods;
+    typedef llvm::iterator_range<CXXMethodDecl::method_iterator>
+        OverriddenMethods;
     SmallVector<OverriddenMethods, 4> Stack;
-    Stack.push_back(std::make_pair(CanonM->begin_overridden_methods(),
-                                   CanonM->end_overridden_methods()));
+    Stack.push_back(llvm::make_range(CanonM->begin_overridden_methods(),
+                                     CanonM->end_overridden_methods()));
     while (!Stack.empty()) {
-      OverriddenMethods OverMethods = Stack.back();
-      Stack.pop_back();
-
-      for (; OverMethods.first != OverMethods.second; ++OverMethods.first) {
-        const CXXMethodDecl *CanonOM
-          = cast<CXXMethodDecl>((*OverMethods.first)->getCanonicalDecl());
+      for (const CXXMethodDecl *OM : Stack.pop_back_val()) {
+        const CXXMethodDecl *CanonOM = OM->getCanonicalDecl();
 
         // C++ [class.virtual]p2:
         //   A virtual member function C::vf of a class object S is
@@ -601,8 +597,8 @@ void FinalOverriderCollector::Collect(const CXXRecordDecl *RD,
 
         // Continue recursion to the methods that this virtual method
         // overrides.
-        Stack.push_back(std::make_pair(CanonOM->begin_overridden_methods(),
-                                       CanonOM->end_overridden_methods()));
+        Stack.push_back(llvm::make_range(CanonOM->begin_overridden_methods(),
+                                         CanonOM->end_overridden_methods()));
       }
     }
 
diff --git a/clang/lib/AST/DeclCXX.cpp b/clang/lib/AST/DeclCXX.cpp
index 9af8c4b242a..a796e0b622f 100644
--- a/clang/lib/AST/DeclCXX.cpp
+++ b/clang/lib/AST/DeclCXX.cpp
@@ -1173,7 +1173,7 @@ static void CollectVisibleConversions(ASTContext &Context,
 
 /// getVisibleConversionFunctions - get all conversion functions visible
 /// in current class; including conversion function templates.
-std::pair<CXXRecordDecl::conversion_iterator,CXXRecordDecl::conversion_iterator>
+llvm::iterator_range<CXXRecordDecl::conversion_iterator>
 CXXRecordDecl::getVisibleConversionFunctions() {
   ASTContext &Ctx = getASTContext();
 
@@ -1189,7 +1189,7 @@ CXXRecordDecl::getVisibleConversionFunctions() {
       data().ComputedVisibleConversions = true;
     }
   }
-  return std::make_pair(Set->begin(), Set->end());
+  return llvm::make_range(Set->begin(), Set->end());
 }
 
 void CXXRecordDecl::removeConversion(const NamedDecl *ConvDecl) {
diff --git a/clang/lib/Analysis/AnalysisDeclContext.cpp b/clang/lib/Analysis/AnalysisDeclContext.cpp
index be66f32e77b..4e623c8d6c3 100644
--- a/clang/lib/Analysis/AnalysisDeclContext.cpp
+++ b/clang/lib/Analysis/AnalysisDeclContext.cpp
@@ -530,14 +530,14 @@ static DeclVec* LazyInitializeReferencedDecls(const BlockDecl *BD,
   return BV;
 }
 
-std::pair<AnalysisDeclContext::referenced_decls_iterator,
-          AnalysisDeclContext::referenced_decls_iterator>
+llvm::iterator_range<AnalysisDeclContext::referenced_decls_iterator>
 AnalysisDeclContext::getReferencedBlockVars(const BlockDecl *BD) {
   if (!ReferencedBlockVars)
     ReferencedBlockVars = new llvm::DenseMap<const BlockDecl*,void*>();
 
-  DeclVec *V = LazyInitializeReferencedDecls(BD, (*ReferencedBlockVars)[BD], A);
-  return std::make_pair(V->begin(), V->end());
+  const DeclVec *V =
+      LazyInitializeReferencedDecls(BD, (*ReferencedBlockVars)[BD], A);
+  return llvm::make_range(V->begin(), V->end());
 }
 
 ManagedAnalysis *&AnalysisDeclContext::getAnalysisImpl(const void *tag) {
diff --git a/clang/lib/Analysis/LiveVariables.cpp b/clang/lib/Analysis/LiveVariables.cpp
index 86b679cb155..0ab158036d8 100644
--- a/clang/lib/Analysis/LiveVariables.cpp
+++ b/clang/lib/Analysis/LiveVariables.cpp
@@ -356,11 +356,8 @@ void TransferFunctions::VisitBinaryOperator(BinaryOperator *B) {
 }
 
 void TransferFunctions::VisitBlockExpr(BlockExpr *BE) {
-  AnalysisDeclContext::referenced_decls_iterator I, E;
-  std::tie(I, E) =
-    LV.analysisContext.getReferencedBlockVars(BE->getBlockDecl());
-  for ( ; I != E ; ++I) {
-    const VarDecl *VD = *I;
+  for (const VarDecl *VD :
+       LV.analysisContext.getReferencedBlockVars(BE->getBlockDecl())) {
     if (isAlwaysAlive(VD))
       continue;
     val.liveDecls = LV.DSetFact.add(val.liveDecls, VD);
diff --git a/clang/lib/Frontend/ASTUnit.cpp b/clang/lib/Frontend/ASTUnit.cpp
index a3998fa351d..b4b9ccdcf1f 100644
--- a/clang/lib/Frontend/ASTUnit.cpp
+++ b/clang/lib/Frontend/ASTUnit.cpp
@@ -2736,7 +2736,7 @@ SourceLocation ASTUnit::getStartOfMainFileID() {
   return SourceMgr->getLocForStartOfFile(FID);
 }
 
-std::pair<PreprocessingRecord::iterator, PreprocessingRecord::iterator>
+llvm::iterator_range<PreprocessingRecord::iterator>
 ASTUnit::getLocalPreprocessingEntities() const {
   if (isMainFileAST()) {
     serialization::ModuleFile &
@@ -2745,20 +2745,18 @@ ASTUnit::getLocalPreprocessingEntities() const {
   }
 
   if (PreprocessingRecord *PPRec = PP->getPreprocessingRecord())
-    return std::make_pair(PPRec->local_begin(), PPRec->local_end());
+    return llvm::make_range(PPRec->local_begin(), PPRec->local_end());
 
-  return std::make_pair(PreprocessingRecord::iterator(),
-                        PreprocessingRecord::iterator());
+  return llvm::make_range(PreprocessingRecord::iterator(),
+                          PreprocessingRecord::iterator());
 }
 
 bool ASTUnit::visitLocalTopLevelDecls(void *context, DeclVisitorFn Fn) {
   if (isMainFileAST()) {
     serialization::ModuleFile &
       Mod = Reader->getModuleManager().getPrimaryModule();
-    ASTReader::ModuleDeclIterator MDI, MDE;
-    std::tie(MDI, MDE) = Reader->getModuleFileLevelDecls(Mod);
-    for (; MDI != MDE; ++MDI) {
-      if (!Fn(context, *MDI))
+    for (const Decl *D : Reader->getModuleFileLevelDecls(Mod)) {
+      if (!Fn(context, D))
         return false;
     }
 
diff --git a/clang/lib/Lex/PreprocessingRecord.cpp b/clang/lib/Lex/PreprocessingRecord.cpp
index 41bb581bb0a..7abd34014d4 100644
--- a/clang/lib/Lex/PreprocessingRecord.cpp
+++ b/clang/lib/Lex/PreprocessingRecord.cpp
@@ -45,22 +45,23 @@ PreprocessingRecord::PreprocessingRecord(SourceManager &SM)
 
 /// \brief Returns a pair of [Begin, End) iterators of preprocessed entities
 /// that source range \p Range encompasses.
-std::pair<PreprocessingRecord::iterator, PreprocessingRecord::iterator>
+llvm::iterator_range<PreprocessingRecord::iterator>
 PreprocessingRecord::getPreprocessedEntitiesInRange(SourceRange Range) {
   if (Range.isInvalid())
-    return std::make_pair(iterator(), iterator());
+    return llvm::make_range(iterator(), iterator());
 
   if (CachedRangeQuery.Range == Range) {
-    return std::make_pair(iterator(this, CachedRangeQuery.Result.first),
-                          iterator(this, CachedRangeQuery.Result.second));
+    return llvm::make_range(iterator(this, CachedRangeQuery.Result.first),
+                            iterator(this, CachedRangeQuery.Result.second));
   }
 
   std::pair<int, int> Res = getPreprocessedEntitiesInRangeSlow(Range);
   
   CachedRangeQuery.Range = Range;
   CachedRangeQuery.Result = Res;
-  
-  return std::make_pair(iterator(this, Res.first), iterator(this, Res.second));
+
+  return llvm::make_range(iterator(this, Res.first),
+                          iterator(this, Res.second));
 }
 
 static bool isPreprocessedEntityIfInFileID(PreprocessedEntity *PPE, FileID FID,
diff --git a/clang/lib/Sema/SemaInit.cpp b/clang/lib/Sema/SemaInit.cpp
index 911b428fbf8..b35110a1e28 100644
--- a/clang/lib/Sema/SemaInit.cpp
+++ b/clang/lib/Sema/SemaInit.cpp
@@ -3634,11 +3634,8 @@ static OverloadingResult TryRefInitWithConversionFunction(Sema &S,
     // functions.
     CXXRecordDecl *T2RecordDecl = cast<CXXRecordDecl>(T2RecordType->getDecl());
 
-    std::pair<CXXRecordDecl::conversion_iterator,
-              CXXRecordDecl::conversion_iterator>
-      Conversions = T2RecordDecl->getVisibleConversionFunctions();
-    for (CXXRecordDecl::conversion_iterator
-           I = Conversions.first, E = Conversions.second; I != E; ++I) {
+    const auto &Conversions = T2RecordDecl->getVisibleConversionFunctions();
+    for (auto I = Conversions.begin(), E = Conversions.end(); I != E; ++I) {
       NamedDecl *D = *I;
       CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(D->getDeclContext());
       if (isa<UsingShadowDecl>(D))
@@ -4266,11 +4263,9 @@ static void TryUserDefinedConversion(Sema &S,
       CXXRecordDecl *SourceRecordDecl
         = cast<CXXRecordDecl>(SourceRecordType->getDecl());
 
-      std::pair<CXXRecordDecl::conversion_iterator,
-                CXXRecordDecl::conversion_iterator>
-        Conversions = SourceRecordDecl->getVisibleConversionFunctions();
-      for (CXXRecordDecl::conversion_iterator
-             I = Conversions.first, E = Conversions.second; I != E; ++I) {
+      const auto &Conversions =
+          SourceRecordDecl->getVisibleConversionFunctions();
+      for (auto I = Conversions.begin(), E = Conversions.end(); I != E; ++I) {
         NamedDecl *D = *I;
         CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(D->getDeclContext());
         if (isa<UsingShadowDecl>(D))
diff --git a/clang/lib/Sema/SemaLookup.cpp b/clang/lib/Sema/SemaLookup.cpp
index d75eb2c2429..8edbc1871b4 100644
--- a/clang/lib/Sema/SemaLookup.cpp
+++ b/clang/lib/Sema/SemaLookup.cpp
@@ -194,10 +194,11 @@ namespace {
     const_iterator begin() const { return list.begin(); }
     const_iterator end() const { return list.end(); }
 
-    std::pair<const_iterator,const_iterator>
+    llvm::iterator_range<const_iterator>
     getNamespacesFor(DeclContext *DC) const {
-      return std::equal_range(begin(), end(), DC->getPrimaryContext(),
-                              UnqualUsingEntry::Comparator());
+      return llvm::make_range(std::equal_range(begin(), end(),
+                                               DC->getPrimaryContext(),
+                                               UnqualUsingEntry::Comparator()));
     }
   };
 }
@@ -765,11 +766,8 @@ CppNamespaceLookup(Sema &S, LookupResult &R, ASTContext &Context,
 
   // Perform direct name lookup into the namespaces nominated by the
   // using directives whose common ancestor is this namespace.
-  UnqualUsingDirectiveSet::const_iterator UI, UEnd;
-  std::tie(UI, UEnd) = UDirs.getNamespacesFor(NS);
-
-  for (; UI != UEnd; ++UI)
-    if (LookupDirect(S, R, UI->getNominatedNamespace()))
+  for (const UnqualUsingEntry &UUE : UDirs.getNamespacesFor(NS))
+    if (LookupDirect(S, R, UUE.getNominatedNamespace()))
       Found = true;
 
   R.resolveKind();
@@ -3199,10 +3197,8 @@ static void LookupVisibleDecls(Scope *S, LookupResult &Result,
   if (Entity) {
     // Lookup visible declarations in any namespaces found by using
     // directives.
-    UnqualUsingDirectiveSet::const_iterator UI, UEnd;
-    std::tie(UI, UEnd) = UDirs.getNamespacesFor(Entity);
-    for (; UI != UEnd; ++UI)
-      LookupVisibleDecls(const_cast<DeclContext *>(UI->getNominatedNamespace()),
+    for (const UnqualUsingEntry &UUE : UDirs.getNamespacesFor(Entity))
+      LookupVisibleDecls(const_cast<DeclContext *>(UUE.getNominatedNamespace()),
                          Result, /*QualifiedNameLookup=*/false,
                          /*InBaseClass=*/false, Consumer, Visited);
   }
diff --git a/clang/lib/Sema/SemaOverload.cpp b/clang/lib/Sema/SemaOverload.cpp
index d364f8d1154..134c88fd9de 100644
--- a/clang/lib/Sema/SemaOverload.cpp
+++ b/clang/lib/Sema/SemaOverload.cpp
@@ -3099,11 +3099,8 @@ IsUserDefinedConversion(Sema &S, Expr *From, QualType ToType,
     if (CXXRecordDecl *FromRecordDecl
          = dyn_cast<CXXRecordDecl>(FromRecordType->getDecl())) {
       // Add all of the conversion functions as candidates.
-      std::pair<CXXRecordDecl::conversion_iterator,
-                CXXRecordDecl::conversion_iterator>
-        Conversions = FromRecordDecl->getVisibleConversionFunctions();
-      for (CXXRecordDecl::conversion_iterator
-             I = Conversions.first, E = Conversions.second; I != E; ++I) {
+      const auto &Conversions = FromRecordDecl->getVisibleConversionFunctions();
+      for (auto I = Conversions.begin(), E = Conversions.end(); I != E; ++I) {
         DeclAccessPair FoundDecl = I.getPair();
         NamedDecl *D = FoundDecl.getDecl();
         CXXRecordDecl *ActingContext = cast<CXXRecordDecl>(D->getDeclContext());
@@ -4045,11 +4042,8 @@ FindConversionForRefInit(Sema &S, ImplicitConversionSequence &ICS,
     = dyn_cast<CXXRecordDecl>(T2->getAs<RecordType>()->getDecl());
 
   OverloadCandidateSet CandidateSet(DeclLoc, OverloadCandidateSet::CSK_Normal);
-  std::pair<CXXRecordDecl::conversion_iterator,
-            CXXRecordDecl::conversion_iterator>
-    Conversions = T2RecordDecl->getVisibleConversionFunctions();
-  for (CXXRecordDecl::conversion_iterator
-         I = Conversions.first, E = Conversions.second; I != E; ++I) {
+  const auto &Conversions = T2RecordDecl->getVisibleConversionFunctions();
+  for (auto I = Conversions.begin(), E = Conversions.end(); I != E; ++I) {
     NamedDecl *D = *I;
     CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(D->getDeclContext());
     if (isa<UsingShadowDecl>(D))
@@ -5399,21 +5393,18 @@ ExprResult Sema::PerformContextualImplicitConversion(
   UnresolvedSet<4>
       ViableConversions; // These are *potentially* viable in C++1y.
   UnresolvedSet<4> ExplicitConversions;
-  std::pair<CXXRecordDecl::conversion_iterator,
-            CXXRecordDecl::conversion_iterator> Conversions =
+  const auto &Conversions =
       cast<CXXRecordDecl>(RecordTy->getDecl())->getVisibleConversionFunctions();
 
   bool HadMultipleCandidates =
-      (std::distance(Conversions.first, Conversions.second) > 1);
+      (std::distance(Conversions.begin(), Conversions.end()) > 1);
 
   // To check that there is only one target type, in C++1y:
   QualType ToType;
   bool HasUniqueTargetType = true;
 
   // Collect explicit or viable (potentially in C++1y) conversions.
-  for (CXXRecordDecl::conversion_iterator I = Conversions.first,
-                                          E = Conversions.second;
-       I != E; ++I) {
+  for (auto I = Conversions.begin(), E = Conversions.end(); I != E; ++I) {
     NamedDecl *D = (*I)->getUnderlyingDecl();
     CXXConversionDecl *Conversion;
     FunctionTemplateDecl *ConvTemplate = dyn_cast<FunctionTemplateDecl>(D);
@@ -6944,12 +6935,7 @@ BuiltinCandidateTypeSet::AddTypesConvertedFrom(QualType Ty,
       return;
 
     CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(TyRec->getDecl());
-    std::pair<CXXRecordDecl::conversion_iterator,
-              CXXRecordDecl::conversion_iterator>
-      Conversions = ClassDecl->getVisibleConversionFunctions();
-    for (CXXRecordDecl::conversion_iterator
-           I = Conversions.first, E = Conversions.second; I != E; ++I) {
-      NamedDecl *D = I.getDecl();
+    for (NamedDecl *D : ClassDecl->getVisibleConversionFunctions()) {
       if (isa<UsingShadowDecl>(D))
         D = cast<UsingShadowDecl>(D)->getTargetDecl();
 
@@ -7013,13 +6999,7 @@ static  Qualifiers CollectVRQualifiers(ASTContext &Context, Expr* ArgExpr) {
     if (!ClassDecl->hasDefinition())
       return VRQuals;
 
-    std::pair<CXXRecordDecl::conversion_iterator,
-              CXXRecordDecl::conversion_iterator>
-      Conversions = ClassDecl->getVisibleConversionFunctions();
-
-    for (CXXRecordDecl::conversion_iterator
-           I = Conversions.first, E = Conversions.second; I != E; ++I) {
-      NamedDecl *D = I.getDecl();
+    for (NamedDecl *D : ClassDecl->getVisibleConversionFunctions()) {
       if (isa<UsingShadowDecl>(D))
         D = cast<UsingShadowDecl>(D)->getTargetDecl();
       if (CXXConversionDecl *Conv = dyn_cast<CXXConversionDecl>(D)) {
@@ -11868,11 +11848,9 @@ Sema::BuildCallToObjectOfClassType(Scope *S, Expr *Obj,
   //   functions for each conversion function declared in an
   //   accessible base class provided the function is not hidden
   //   within T by another intervening declaration.
-  std::pair<CXXRecordDecl::conversion_iterator,
-            CXXRecordDecl::conversion_iterator> Conversions
-    = cast<CXXRecordDecl>(Record->getDecl())->getVisibleConversionFunctions();
-  for (CXXRecordDecl::conversion_iterator
-         I = Conversions.first, E = Conversions.second; I != E; ++I) {
+  const auto &Conversions =
+      cast<CXXRecordDecl>(Record->getDecl())->getVisibleConversionFunctions();
+  for (auto I = Conversions.begin(), E = Conversions.end(); I != E; ++I) {
     NamedDecl *D = *I;
     CXXRecordDecl *ActingContext = cast<CXXRecordDecl>(D->getDeclContext());
     if (isa<UsingShadowDecl>(D))
diff --git a/clang/lib/Sema/SemaPseudoObject.cpp b/clang/lib/Sema/SemaPseudoObject.cpp
index 5e92d5d07c5..89fb76cfceb 100644
--- a/clang/lib/Sema/SemaPseudoObject.cpp
+++ b/clang/lib/Sema/SemaPseudoObject.cpp
@@ -1051,17 +1051,13 @@ Sema::ObjCSubscriptKind
   
   // Look for a conversion to an integral, enumeration type, or
   // objective-C pointer type.
-  std::pair<CXXRecordDecl::conversion_iterator,
-            CXXRecordDecl::conversion_iterator> Conversions
-    = cast<CXXRecordDecl>(RecordTy->getDecl())->getVisibleConversionFunctions();
-  
   int NoIntegrals=0, NoObjCIdPointers=0;
   SmallVector<CXXConversionDecl *, 4> ConversionDecls;
-    
-  for (CXXRecordDecl::conversion_iterator
-         I = Conversions.first, E = Conversions.second; I != E; ++I) {
-    if (CXXConversionDecl *Conversion
-        = dyn_cast<CXXConversionDecl>((*I)->getUnderlyingDecl())) {
+
+  for (NamedDecl *D : cast<CXXRecordDecl>(RecordTy->getDecl())
+                          ->getVisibleConversionFunctions()) {
+    if (CXXConversionDecl *Conversion =
+            dyn_cast<CXXConversionDecl>(D->getUnderlyingDecl())) {
       QualType CT = Conversion->getConversionType().getNonReferenceType();
       if (CT->isIntegralOrEnumerationType()) {
         ++NoIntegrals;
diff --git a/clang/lib/Serialization/ASTReader.cpp b/clang/lib/Serialization/ASTReader.cpp
index 5b9ad12a3c5..aa1cdc080ee 100644
--- a/clang/lib/Serialization/ASTReader.cpp
+++ b/clang/lib/Serialization/ASTReader.cpp
@@ -4823,21 +4823,22 @@ ASTReader::getModulePreprocessedEntity(unsigned GlobalIndex) {
   return std::make_pair(M, LocalIndex);
 }
 
-std::pair<PreprocessingRecord::iterator, PreprocessingRecord::iterator>
+llvm::iterator_range<PreprocessingRecord::iterator>
 ASTReader::getModulePreprocessedEntities(ModuleFile &Mod) const {
   if (PreprocessingRecord *PPRec = PP.getPreprocessingRecord())
     return PPRec->getIteratorsForLoadedRange(Mod.BasePreprocessedEntityID,
                                              Mod.NumPreprocessedEntities);
 
-  return std::make_pair(PreprocessingRecord::iterator(),
-                        PreprocessingRecord::iterator());
+  return llvm::make_range(PreprocessingRecord::iterator(),
+                          PreprocessingRecord::iterator());
 }
 
-std::pair<ASTReader::ModuleDeclIterator, ASTReader::ModuleDeclIterator>
+llvm::iterator_range<ASTReader::ModuleDeclIterator>
 ASTReader::getModuleFileLevelDecls(ModuleFile &Mod) {
-  return std::make_pair(ModuleDeclIterator(this, &Mod, Mod.FileSortedDecls),
-                        ModuleDeclIterator(this, &Mod,
-                                 Mod.FileSortedDecls + Mod.NumFileSortedDecls));
+  return llvm::make_range(
+      ModuleDeclIterator(this, &Mod, Mod.FileSortedDecls),
+      ModuleDeclIterator(this, &Mod,
+                         Mod.FileSortedDecls + Mod.NumFileSortedDecls));
 }
 
 PreprocessedEntity *ASTReader::ReadPreprocessedEntity(unsigned Index) {
diff --git a/clang/lib/StaticAnalyzer/Checkers/RetainCountChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/RetainCountChecker.cpp
index ac74ecd0f49..fee8e766f6c 100644
--- a/clang/lib/StaticAnalyzer/Checkers/RetainCountChecker.cpp
+++ b/clang/lib/StaticAnalyzer/Checkers/RetainCountChecker.cpp
@@ -1788,12 +1788,11 @@ namespace {
       addGCModeDescription(LOpts, GCEnabled);
     }
 
-    std::pair<ranges_iterator, ranges_iterator> getRanges() override {
+    llvm::iterator_range<ranges_iterator> getRanges() override {
       const CFRefBug& BugTy = static_cast<CFRefBug&>(getBugType());
       if (!BugTy.isLeak())
         return BugReport::getRanges();
-      else
-        return std::make_pair(ranges_iterator(), ranges_iterator());
+      return llvm::make_range(ranges_iterator(), ranges_iterator());
     }
   };
 
diff --git a/clang/lib/StaticAnalyzer/Core/BugReporter.cpp b/clang/lib/StaticAnalyzer/Core/BugReporter.cpp
index dff81e383ea..0a58e3effec 100644
--- a/clang/lib/StaticAnalyzer/Core/BugReporter.cpp
+++ b/clang/lib/StaticAnalyzer/Core/BugReporter.cpp
@@ -2702,22 +2702,22 @@ const Stmt *BugReport::getStmt() const {
   return S;
 }
 
-std::pair<BugReport::ranges_iterator, BugReport::ranges_iterator>
-BugReport::getRanges() {
-    // If no custom ranges, add the range of the statement corresponding to
-    // the error node.
-    if (Ranges.empty()) {
-      if (const Expr *E = dyn_cast_or_null<Expr>(getStmt()))
-        addRange(E->getSourceRange());
-      else
-        return std::make_pair(ranges_iterator(), ranges_iterator());
-    }
+llvm::iterator_range<BugReport::ranges_iterator> BugReport::getRanges() {
+  // If no custom ranges, add the range of the statement corresponding to
+  // the error node.
+  if (Ranges.empty()) {
+    if (const Expr *E = dyn_cast_or_null<Expr>(getStmt()))
+      addRange(E->getSourceRange());
+    else
+      return llvm::make_range(ranges_iterator(), ranges_iterator());
+  }
 
-    // User-specified absence of range info.
-    if (Ranges.size() == 1 && !Ranges.begin()->isValid())
-      return std::make_pair(ranges_iterator(), ranges_iterator());
+  // User-specified absence of range info.
+  if (Ranges.size() == 1 && !Ranges.begin()->isValid())
+    return llvm::make_range(ranges_iterator(), ranges_iterator());
 
-    return std::make_pair(Ranges.begin(), Ranges.end());
+  return llvm::iterator_range<BugReport::ranges_iterator>(Ranges.begin(),
+                                                          Ranges.end());
 }
 
 PathDiagnosticLocation BugReport::getLocation(const SourceManager &SM) const {
@@ -3434,10 +3434,8 @@ void BugReporter::FlushReport(BugReport *exampleReport,
     PathDiagnosticLocation L = exampleReport->getLocation(getSourceManager());
     auto piece = llvm::make_unique<PathDiagnosticEventPiece>(
         L, exampleReport->getDescription());
-    BugReport::ranges_iterator Beg, End;
-    std::tie(Beg, End) = exampleReport->getRanges();
-    for ( ; Beg != End; ++Beg)
-      piece->addRange(*Beg);
+    for (const SourceRange &Range : exampleReport->getRanges())
+      piece->addRange(Range);
     D->setEndOfPath(std::move(piece));
   }
 
diff --git a/clang/lib/StaticAnalyzer/Core/BugReporterVisitors.cpp b/clang/lib/StaticAnalyzer/Core/BugReporterVisitors.cpp
index 2d56bd08849..b906cc9e762 100644
--- a/clang/lib/StaticAnalyzer/Core/BugReporterVisitors.cpp
+++ b/clang/lib/StaticAnalyzer/Core/BugReporterVisitors.cpp
@@ -111,15 +111,14 @@ std::unique_ptr<PathDiagnosticPiece> BugReporterVisitor::getDefaultEndPath(
   PathDiagnosticLocation L =
     PathDiagnosticLocation::createEndOfPath(EndPathNode,BRC.getSourceManager());
 
-  BugReport::ranges_iterator Beg, End;
-  std::tie(Beg, End) = BR.getRanges();
+  const auto &Ranges = BR.getRanges();
 
   // Only add the statement itself as a range if we didn't specify any
   // special ranges for this report.
-  auto P = llvm::make_unique<PathDiagnosticEventPiece>(L, BR.getDescription(),
-                                                       Beg == End);
-  for (; Beg != End; ++Beg)
-    P->addRange(*Beg);
+  auto P = llvm::make_unique<PathDiagnosticEventPiece>(
+      L, BR.getDescription(), Ranges.begin() == Ranges.end());
+  for (const SourceRange &Range : Ranges)
+    P->addRange(Range);
 
   return std::move(P);
 }
diff --git a/clang/lib/StaticAnalyzer/Core/MemRegion.cpp b/clang/lib/StaticAnalyzer/Core/MemRegion.cpp
index 76cead62329..1fa675433b5 100644
--- a/clang/lib/StaticAnalyzer/Core/MemRegion.cpp
+++ b/clang/lib/StaticAnalyzer/Core/MemRegion.cpp
@@ -1372,10 +1372,11 @@ void BlockDataRegion::LazyInitializeReferencedVars() {
     return;
 
   AnalysisDeclContext *AC = getCodeRegion()->getAnalysisDeclContext();
-  AnalysisDeclContext::referenced_decls_iterator I, E;
-  std::tie(I, E) = AC->getReferencedBlockVars(BC->getDecl());
+  const auto &ReferencedBlockVars = AC->getReferencedBlockVars(BC->getDecl());
+  auto NumBlockVars =
+      std::distance(ReferencedBlockVars.begin(), ReferencedBlockVars.end());
 
-  if (I == E) {
+  if (NumBlockVars == 0) {
     ReferencedVars = (void*) 0x1;
     return;
   }
@@ -1386,14 +1387,14 @@ void BlockDataRegion::LazyInitializeReferencedVars() {
 
   typedef BumpVector<const MemRegion*> VarVec;
   VarVec *BV = (VarVec*) A.Allocate<VarVec>();
-  new (BV) VarVec(BC, E - I);
+  new (BV) VarVec(BC, NumBlockVars);
   VarVec *BVOriginal = (VarVec*) A.Allocate<VarVec>();
-  new (BVOriginal) VarVec(BC, E - I);
+  new (BVOriginal) VarVec(BC, NumBlockVars);
 
-  for ( ; I != E; ++I) {
+  for (const VarDecl *VD : ReferencedBlockVars) {
     const VarRegion *VR = nullptr;
     const VarRegion *OriginalVR = nullptr;
-    std::tie(VR, OriginalVR) = getCaptureRegions(*I);
+    std::tie(VR, OriginalVR) = getCaptureRegions(VD);
     assert(VR);
     assert(OriginalVR);
     BV->push_back(VR, BC);