Iterate over StringMaps using structured bindings. NFCI.

clang/lib/Serialization/GlobalModuleIndex.cpp

@@ -815,10 +815,8 @@ bool GlobalModuleIndexBuilder::writeIndex(llvm::BitstreamWriter &Stream) {
     IdentifierIndexWriterTrait Trait;
 
     // Populate the hash table.
-    for (InterestingIdentifierMap::iterator I = InterestingIdentifiers.begin(),
+    for (auto &[Identifier, IDs] : InterestingIdentifiers) {
-                                            IEnd = InterestingIdentifiers.end();
+      Generator.insert(Identifier, IDs, Trait);
-         I != IEnd; ++I) {
-      Generator.insert(I->first(), I->second, Trait);
     }
 
     // Create the on-disk hash table in a buffer.

llvm/include/llvm/ProfileData/SampleProf.h

@@ -405,8 +405,8 @@ public:
   /// Sort call targets in descending order of call frequency.
   static const SortedCallTargetSet SortCallTargets(const CallTargetMap &Targets) {
     SortedCallTargetSet SortedTargets;
-    for (const auto &I : Targets) {
+    for (const auto &[Target, Frequency] : Targets) {
-      SortedTargets.emplace(I.first(), I.second);
+      SortedTargets.emplace(Target, Frequency);
     }
     return SortedTargets;
   }
@@ -415,8 +415,8 @@ public:
   static const CallTargetMap adjustCallTargets(const CallTargetMap &Targets,
                                                float DistributionFactor) {
     CallTargetMap AdjustedTargets;
-    for (const auto &I : Targets) {
+    for (const auto &[Target, Frequency] : Targets) {
-      AdjustedTargets[I.first()] = I.second * DistributionFactor;
+      AdjustedTargets[Target] = Frequency * DistributionFactor;
     }
     return AdjustedTargets;
   }

llvm/include/llvm/Transforms/IPO/ProfiledCallGraph.h

@@ -159,9 +159,9 @@ private:
     addProfiledFunction(Samples.getFuncName());
 
     for (const auto &Sample : Samples.getBodySamples()) {
-      for (const auto &Target : Sample.second.getCallTargets()) {
+      for (const auto &[Target, Frequency] : Sample.second.getCallTargets()) {
-        addProfiledFunction(Target.first());
+        addProfiledFunction(Target);
-        addProfiledCall(Samples.getFuncName(), Target.first(), Target.second);
+        addProfiledCall(Samples.getFuncName(), Target, Frequency);
       }
     }
 

llvm/lib/CodeGen/CommandFlags.cpp

@@ -592,8 +592,8 @@ std::string codegen::getFeaturesStr() {
   if (getMCPU() == "native") {
     StringMap<bool> HostFeatures;
     if (sys::getHostCPUFeatures(HostFeatures))
-      for (auto &F : HostFeatures)
+      for (const auto &[Feature, IsEnabled] : HostFeatures)
-        Features.AddFeature(F.first(), F.second);
+        Features.AddFeature(Feature, IsEnabled);
   }
 
   for (auto const &MAttr : getMAttrs())
@@ -612,8 +612,8 @@ std::vector<std::string> codegen::getFeatureList() {
   if (getMCPU() == "native") {
     StringMap<bool> HostFeatures;
     if (sys::getHostCPUFeatures(HostFeatures))
-      for (auto &F : HostFeatures)
+      for (const auto &[Feature, IsEnabled] : HostFeatures)
-        Features.AddFeature(F.first(), F.second);
+        Features.AddFeature(Feature, IsEnabled);
   }
 
   for (auto const &MAttr : getMAttrs())

llvm/lib/IR/AsmWriter.cpp

@@ -1059,8 +1059,8 @@ int SlotTracker::processIndex() {
   // assigned consecutively. Since the StringMap iteration order isn't
   // guaranteed, use a std::map to order by module ID before assigning slots.
   std::map<uint64_t, StringRef> ModuleIdToPathMap;
-  for (auto &ModPath : TheIndex->modulePaths())
+  for (auto &[ModPath, ModId] : TheIndex->modulePaths())
-    ModuleIdToPathMap[ModPath.second.first] = ModPath.first();
+    ModuleIdToPathMap[ModId.first] = ModPath;
   for (auto &ModPair : ModuleIdToPathMap)
     CreateModulePathSlot(ModPair.second);
 
@@ -2875,13 +2875,12 @@ void AssemblyWriter::printModuleSummaryIndex() {
   std::string RegularLTOModuleName =
       ModuleSummaryIndex::getRegularLTOModuleName();
   moduleVec.resize(TheIndex->modulePaths().size());
-  for (auto &ModPath : TheIndex->modulePaths())
+  for (auto &[ModPath, ModId] : TheIndex->modulePaths())
-    moduleVec[Machine.getModulePathSlot(ModPath.first())] = std::make_pair(
+    moduleVec[Machine.getModulePathSlot(ModPath)] = std::make_pair(
         // A module id of -1 is a special entry for a regular LTO module created
         // during the thin link.
-        ModPath.second.first == -1u ? RegularLTOModuleName
+        ModId.first == -1u ? RegularLTOModuleName : std::string(ModPath),
-                                    : (std::string)std::string(ModPath.first()),
+        ModId.second);
-        ModPath.second.second);
 
   unsigned i = 0;
   for (auto &ModPair : moduleVec) {

llvm/lib/Target/TargetMachineC.cpp

@@ -258,8 +258,8 @@ char *LLVMGetHostCPUFeatures(void) {
   StringMap<bool> HostFeatures;
 
   if (sys::getHostCPUFeatures(HostFeatures))
-    for (auto &F : HostFeatures)
+    for (const auto &[Feature, IsEnabled] : HostFeatures)
-      Features.AddFeature(F.first(), F.second);
+      Features.AddFeature(Feature, IsEnabled);
 
   return strdup(Features.getString().c_str());
 }

mlir/lib/Dialect/Transform/IR/TransformOps.cpp

@@ -88,8 +88,8 @@ LogicalResult PatternApplicatorExtension::findAllMatches(
     // also used by the following operations.
     auto *dialect =
         root->getContext()->getLoadedDialect<transform::TransformDialect>();
-    for (const auto &pair : dialect->getPDLConstraintHooks())
+    for (const auto &[name, constraintFn] : dialect->getPDLConstraintHooks())
-      patternModule.registerConstraintFunction(pair.first(), pair.second);
+      patternModule.registerConstraintFunction(name, constraintFn);
 
     // Register a noop rewriter because PDL requires patterns to end with some
     // rewrite call.

mlir/lib/ExecutionEngine/ExecutionEngine.cpp

@@ -145,8 +145,8 @@ bool ExecutionEngine::setupTargetTriple(Module *llvmModule) {
   llvm::StringMap<bool> hostFeatures;
 
   if (llvm::sys::getHostCPUFeatures(hostFeatures))
-    for (auto &f : hostFeatures)
+    for (const auto &[feature, isEnabled] : hostFeatures)
-      features.AddFeature(f.first(), f.second);
+      features.AddFeature(feature, isEnabled);
 
   std::unique_ptr<llvm::TargetMachine> machine(target->createTargetMachine(
       targetTriple, cpu, features.getString(), {}, {}));