diff --git a/lib/IR/AsmWriter.cpp b/lib/IR/AsmWriter.cpp
index 43aba4efb6e..3ae3bf430d2 100644
--- a/lib/IR/AsmWriter.cpp
+++ b/lib/IR/AsmWriter.cpp
@@ -4373,9 +4373,8 @@ void AssemblyWriter::writeMDNode(unsigned Slot, const MDNode *Node) {
 void AssemblyWriter::writeAllMDNodes() {
   SmallVector<const MDNode *, 16> Nodes;
   Nodes.resize(Machine.mdn_size());
-  for (SlotTracker::mdn_iterator I = Machine.mdn_begin(), E = Machine.mdn_end();
-       I != E; ++I)
-    Nodes[I->second] = cast<MDNode>(I->first);
+  for (auto &I : llvm::make_range(Machine.mdn_begin(), Machine.mdn_end()))
+    Nodes[I.second] = cast<MDNode>(I.first);
 
   for (unsigned i = 0, e = Nodes.size(); i != e; ++i) {
     writeMDNode(i, Nodes[i]);
diff --git a/lib/IR/Core.cpp b/lib/IR/Core.cpp
index 6631a4ac224..7398a7efd8c 100644
--- a/lib/IR/Core.cpp
+++ b/lib/IR/Core.cpp
@@ -3280,9 +3280,8 @@ unsigned LLVMGetNumHandlers(LLVMValueRef CatchSwitch) {
 
 void LLVMGetHandlers(LLVMValueRef CatchSwitch, LLVMBasicBlockRef *Handlers) {
   CatchSwitchInst *CSI = unwrap<CatchSwitchInst>(CatchSwitch);
-  for (CatchSwitchInst::handler_iterator I = CSI->handler_begin(),
-                                         E = CSI->handler_end(); I != E; ++I)
-    *Handlers++ = wrap(*I);
+  for (const BasicBlock *H : CSI->handlers())
+    *Handlers++ = wrap(H);
 }
 
 LLVMValueRef LLVMGetParentCatchSwitch(LLVMValueRef CatchPad) {
diff --git a/lib/IR/ModuleSummaryIndex.cpp b/lib/IR/ModuleSummaryIndex.cpp
index c2ded87c494..f4ac6caf4f9 100644
--- a/lib/IR/ModuleSummaryIndex.cpp
+++ b/lib/IR/ModuleSummaryIndex.cpp
@@ -292,10 +292,9 @@ void ModuleSummaryIndex::propagateAttributes(
     if (!IsDSOLocal)
       // Mark the flag in all summaries false so that we can do quick check
       // without going through the whole list.
-      llvm::for_each(P.second.SummaryList,
-                     [](const std::unique_ptr<GlobalValueSummary> &Summary) {
-                       return Summary->setDSOLocal(false);
-                     });
+      for (const std::unique_ptr<GlobalValueSummary> &Summary :
+           P.second.SummaryList)
+        Summary->setDSOLocal(false);
   }
   setWithAttributePropagation();
   setWithDSOLocalPropagation();
diff --git a/lib/IR/Verifier.cpp b/lib/IR/Verifier.cpp
index c382600683e..47bfbfb1952 100644
--- a/lib/IR/Verifier.cpp
+++ b/lib/IR/Verifier.cpp
@@ -3671,10 +3671,9 @@ void Verifier::visitStoreInst(StoreInst &SI) {
 /// Check that SwiftErrorVal is used as a swifterror argument in CS.
 void Verifier::verifySwiftErrorCall(CallBase &Call,
                                     const Value *SwiftErrorVal) {
-  unsigned Idx = 0;
-  for (auto I = Call.arg_begin(), E = Call.arg_end(); I != E; ++I, ++Idx) {
-    if (*I == SwiftErrorVal) {
-      Assert(Call.paramHasAttr(Idx, Attribute::SwiftError),
+  for (const auto &I : llvm::enumerate(Call.args())) {
+    if (I.value() == SwiftErrorVal) {
+      Assert(Call.paramHasAttr(I.index(), Attribute::SwiftError),
              "swifterror value when used in a callsite should be marked "
              "with swifterror attribute",
              SwiftErrorVal, Call);