diff --git a/llvm/include/llvm/IR/DataLayout.h b/llvm/include/llvm/IR/DataLayout.h
index eb031613a9359..eae409e75293d 100644
--- a/llvm/include/llvm/IR/DataLayout.h
+++ b/llvm/include/llvm/IR/DataLayout.h
@@ -260,10 +260,7 @@ class DataLayout {
   ///
   /// The width is specified in bits.
   bool isLegalInteger(uint64_t Width) const {
-    for (unsigned LegalIntWidth : LegalIntWidths)
-      if (LegalIntWidth == Width)
-        return true;
-    return false;
+    return llvm::is_contained(LegalIntWidths, Width);
   }
 
   bool isIllegalInteger(uint64_t Width) const { return !isLegalInteger(Width); }
diff --git a/llvm/include/llvm/TableGen/Record.h b/llvm/include/llvm/TableGen/Record.h
index b79de83ac698c..e75b7f01c868a 100644
--- a/llvm/include/llvm/TableGen/Record.h
+++ b/llvm/include/llvm/TableGen/Record.h
@@ -1568,9 +1568,7 @@ class Record {
   void getDirectSuperClasses(SmallVectorImpl<Record *> &Classes) const;
 
   bool isTemplateArg(Init *Name) const {
-    for (Init *TA : TemplateArgs)
-      if (TA == Name) return true;
-    return false;
+    return llvm::is_contained(TemplateArgs, Name);
   }
 
   const RecordVal *getValue(const Init *Name) const {
diff --git a/llvm/lib/Analysis/AssumeBundleQueries.cpp b/llvm/lib/Analysis/AssumeBundleQueries.cpp
index 0084e2f13f5f9..273b38a9567e5 100644
--- a/llvm/lib/Analysis/AssumeBundleQueries.cpp
+++ b/llvm/lib/Analysis/AssumeBundleQueries.cpp
@@ -157,9 +157,8 @@ llvm::getKnowledgeFromUse(const Use *U,
     return RetainedKnowledge::none();
   RetainedKnowledge RK =
       getKnowledgeFromBundle(*cast<CallInst>(U->getUser()), *Bundle);
-  for (auto Attr : AttrKinds)
-    if (Attr == RK.AttrKind)
-      return RK;
+  if (llvm::is_contained(AttrKinds, RK.AttrKind))
+    return RK;
   return RetainedKnowledge::none();
 }
 
diff --git a/llvm/lib/Analysis/LoopInfo.cpp b/llvm/lib/Analysis/LoopInfo.cpp
index da894ef45bb25..b298c4285503f 100644
--- a/llvm/lib/Analysis/LoopInfo.cpp
+++ b/llvm/lib/Analysis/LoopInfo.cpp
@@ -616,15 +616,7 @@ bool Loop::isAnnotatedParallel() const {
       if (!LoopIdMD)
         return false;
 
-      bool LoopIdMDFound = false;
-      for (const MDOperand &MDOp : LoopIdMD->operands()) {
-        if (MDOp == DesiredLoopIdMetadata) {
-          LoopIdMDFound = true;
-          break;
-        }
-      }
-
-      if (!LoopIdMDFound)
+      if (!llvm::is_contained(LoopIdMD->operands(), DesiredLoopIdMetadata))
         return false;
     }
   }
diff --git a/llvm/lib/CodeGen/MachineModuleInfo.cpp b/llvm/lib/CodeGen/MachineModuleInfo.cpp
index 5565b9cededac..0379dbd0dcedc 100644
--- a/llvm/lib/CodeGen/MachineModuleInfo.cpp
+++ b/llvm/lib/CodeGen/MachineModuleInfo.cpp
@@ -222,10 +222,8 @@ MachineModuleInfo::getAddrLabelSymbolToEmit(const BasicBlock *BB) {
 /// \{
 
 void MachineModuleInfo::addPersonality(const Function *Personality) {
-  for (unsigned i = 0; i < Personalities.size(); ++i)
-    if (Personalities[i] == Personality)
-      return;
-  Personalities.push_back(Personality);
+  if (!llvm::is_contained(Personalities, Personality))
+    Personalities.push_back(Personality);
 }
 
 /// \}
diff --git a/llvm/lib/CodeGen/MachineVerifier.cpp b/llvm/lib/CodeGen/MachineVerifier.cpp
index ed16ca20acecd..dbdc20fb4f8fe 100644
--- a/llvm/lib/CodeGen/MachineVerifier.cpp
+++ b/llvm/lib/CodeGen/MachineVerifier.cpp
@@ -2181,12 +2181,8 @@ void MachineVerifier::checkLiveness(const MachineOperand *MO, unsigned MONum) {
             if (!Register::isPhysicalRegister(MOP.getReg()))
               continue;
 
-            for (const MCPhysReg &SubReg : TRI->subregs(MOP.getReg())) {
-              if (SubReg == Reg) {
-                Bad = false;
-                break;
-              }
-            }
+            if (llvm::is_contained(TRI->subregs(MOP.getReg()), Reg))
+              Bad = false;
           }
         }
         if (Bad)
diff --git a/llvm/lib/ExecutionEngine/JITLink/ELF_x86_64.cpp b/llvm/lib/ExecutionEngine/JITLink/ELF_x86_64.cpp
index 2a6b3eb19dedb..5a0c8976cf516 100644
--- a/llvm/lib/ExecutionEngine/JITLink/ELF_x86_64.cpp
+++ b/llvm/lib/ExecutionEngine/JITLink/ELF_x86_64.cpp
@@ -204,10 +204,7 @@ static Error optimizeELF_x86_64_GOTAndStubs(LinkGraph &G) {
 }
 
 static bool isDwarfSection(StringRef SectionName) {
-  for (auto &DwarfSectionName : DwarfSectionNames)
-    if (SectionName == DwarfSectionName)
-      return true;
-  return false;
+  return llvm::is_contained(DwarfSectionNames, SectionName);
 }
 
 namespace llvm {
diff --git a/llvm/lib/Object/IRSymtab.cpp b/llvm/lib/Object/IRSymtab.cpp
index e39cb732add10..8e6b6a373a2e2 100644
--- a/llvm/lib/Object/IRSymtab.cpp
+++ b/llvm/lib/Object/IRSymtab.cpp
@@ -247,11 +247,7 @@ Error Builder::addSymbol(const ModuleSymbolTable &Msymtab,
 
   setStr(Sym.IRName, GV->getName());
 
-  bool IsBuiltinFunc = false;
-
-  for (const char *LibcallName : LibcallRoutineNames)
-    if (GV->getName() == LibcallName)
-      IsBuiltinFunc = true;
+  bool IsBuiltinFunc = llvm::is_contained(LibcallRoutineNames, GV->getName());
 
   if (Used.count(GV) || IsBuiltinFunc)
     Sym.Flags |= 1 << storage::Symbol::FB_used;
diff --git a/llvm/lib/Passes/StandardInstrumentations.cpp b/llvm/lib/Passes/StandardInstrumentations.cpp
index 86aaab5a8156d..601957034489e 100644
--- a/llvm/lib/Passes/StandardInstrumentations.cpp
+++ b/llvm/lib/Passes/StandardInstrumentations.cpp
@@ -782,11 +782,7 @@ bool PrintIRInstrumentation::shouldPrintBeforePass(StringRef PassID) {
     return true;
 
   StringRef PassName = PIC->getPassNameForClassName(PassID);
-  for (const auto &P : printBeforePasses()) {
-    if (PassName == P)
-      return true;
-  }
-  return false;
+  return llvm::is_contained(printBeforePasses(), PassName);
 }
 
 bool PrintIRInstrumentation::shouldPrintAfterPass(StringRef PassID) {
@@ -794,11 +790,7 @@ bool PrintIRInstrumentation::shouldPrintAfterPass(StringRef PassID) {
     return true;
 
   StringRef PassName = PIC->getPassNameForClassName(PassID);
-  for (const auto &P : printAfterPasses()) {
-    if (PassName == P)
-      return true;
-  }
-  return false;
+  return llvm::is_contained(printAfterPasses(), PassName);
 }
 
 void PrintIRInstrumentation::registerCallbacks(
diff --git a/llvm/lib/TableGen/Record.cpp b/llvm/lib/TableGen/Record.cpp
index 18348b4c96417..13212098514d3 100644
--- a/llvm/lib/TableGen/Record.cpp
+++ b/llvm/lib/TableGen/Record.cpp
@@ -2715,10 +2715,8 @@ Init *RecordResolver::resolve(Init *VarName) {
   if (Val)
     return Val;
 
-  for (Init *S : Stack) {
-    if (S == VarName)
-      return nullptr; // prevent infinite recursion
-  }
+  if (llvm::is_contained(Stack, VarName))
+    return nullptr; // prevent infinite recursion
 
   if (RecordVal *RV = getCurrentRecord()->getValue(VarName)) {
     if (!isa<UnsetInit>(RV->getValue())) {
diff --git a/llvm/lib/Target/AMDGPU/AMDGPUMachineCFGStructurizer.cpp b/llvm/lib/Target/AMDGPU/AMDGPUMachineCFGStructurizer.cpp
index b6a69b2819ee0..4a9d5cded732d 100644
--- a/llvm/lib/Target/AMDGPU/AMDGPUMachineCFGStructurizer.cpp
+++ b/llvm/lib/Target/AMDGPU/AMDGPUMachineCFGStructurizer.cpp
@@ -1419,11 +1419,7 @@ void AMDGPUMachineCFGStructurizer::extractKilledPHIs(MachineBasicBlock *MBB) {
 
 static bool isPHIRegionIndex(SmallVector<unsigned, 2> PHIRegionIndices,
                              unsigned Index) {
-  for (auto i : PHIRegionIndices) {
-    if (i == Index)
-      return true;
-  }
-  return false;
+  llvm::is_contained(PHIRegionIndices, Index);
 }
 
 bool AMDGPUMachineCFGStructurizer::shrinkPHI(MachineInstr &PHI,
diff --git a/llvm/lib/Target/Hexagon/HexagonHardwareLoops.cpp b/llvm/lib/Target/Hexagon/HexagonHardwareLoops.cpp
index 2f23e8643720c..7d5880de18460 100644
--- a/llvm/lib/Target/Hexagon/HexagonHardwareLoops.cpp
+++ b/llvm/lib/Target/Hexagon/HexagonHardwareLoops.cpp
@@ -1370,10 +1370,8 @@ bool HexagonHardwareLoops::isLoopFeeder(MachineLoop *L, MachineBasicBlock *A,
     LLVM_DEBUG(dbgs() << "\nhw_loop head, "
                       << printMBBReference(**L->block_begin()));
     // Ignore all BBs that form Loop.
-    for (MachineBasicBlock *MBB : L->getBlocks()) {
-      if (A == MBB)
-        return false;
-    }
+    if (llvm::is_contained(L->getBlocks(), A))
+      return false;
     MachineInstr *Def = MRI->getVRegDef(MO->getReg());
     LoopFeederPhi.insert(std::make_pair(MO->getReg(), Def));
     return true;
diff --git a/llvm/lib/Target/Mips/MipsLegalizerInfo.cpp b/llvm/lib/Target/Mips/MipsLegalizerInfo.cpp
index 2692c08b93def..03aa88d31e6e4 100644
--- a/llvm/lib/Target/Mips/MipsLegalizerInfo.cpp
+++ b/llvm/lib/Target/Mips/MipsLegalizerInfo.cpp
@@ -60,10 +60,7 @@ CheckTy0Ty1MemSizeAlign(const LegalityQuery &Query,
 
 static bool CheckTyN(unsigned N, const LegalityQuery &Query,
                      std::initializer_list<LLT> SupportedValues) {
-  for (auto &Val : SupportedValues)
-    if (Val == Query.Types[N])
-      return true;
-  return false;
+  return llvm::is_contained(SupportedValues, Query.Types[N]);
 }
 
 MipsLegalizerInfo::MipsLegalizerInfo(const MipsSubtarget &ST) {
diff --git a/llvm/lib/Target/X86/X86SelectionDAGInfo.cpp b/llvm/lib/Target/X86/X86SelectionDAGInfo.cpp
index e76908ef4bc40..a3238e6317a09 100644
--- a/llvm/lib/Target/X86/X86SelectionDAGInfo.cpp
+++ b/llvm/lib/Target/X86/X86SelectionDAGInfo.cpp
@@ -41,11 +41,7 @@ bool X86SelectionDAGInfo::isBaseRegConflictPossible(
 
   const X86RegisterInfo *TRI = static_cast<const X86RegisterInfo *>(
       DAG.getSubtarget().getRegisterInfo());
-  Register BaseReg = TRI->getBaseRegister();
-  for (unsigned R : ClobberSet)
-    if (BaseReg == R)
-      return true;
-  return false;
+  return llvm::is_contained(ClobberSet, TRI->getBaseRegister());
 }
 
 SDValue X86SelectionDAGInfo::EmitTargetCodeForMemset(
diff --git a/llvm/lib/Transforms/IPO/ArgumentPromotion.cpp b/llvm/lib/Transforms/IPO/ArgumentPromotion.cpp
index d34634111ecf0..7dd9e71aedce4 100644
--- a/llvm/lib/Transforms/IPO/ArgumentPromotion.cpp
+++ b/llvm/lib/Transforms/IPO/ArgumentPromotion.cpp
@@ -986,13 +986,8 @@ promoteArguments(Function *F, function_ref<AAResults &(Function &F)> AARGetter,
     // function, we could end up infinitely peeling the function argument.
     if (isSelfRecursive) {
       if (StructType *STy = dyn_cast<StructType>(AgTy)) {
-        bool RecursiveType = false;
-        for (const auto *EltTy : STy->elements()) {
-          if (EltTy == PtrArg->getType()) {
-            RecursiveType = true;
-            break;
-          }
-        }
+        bool RecursiveType =
+            llvm::is_contained(STy->elements(), PtrArg->getType());
         if (RecursiveType)
           continue;
       }
diff --git a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
index 0057c35570cc8..df44e5010c61a 100644
--- a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
+++ b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
@@ -207,9 +207,8 @@ bool llvm::MergeBlockIntoPredecessor(BasicBlock *BB, DomTreeUpdater *DTU,
 
   // Can't merge if there is PHI loop.
   for (PHINode &PN : BB->phis())
-    for (Value *IncValue : PN.incoming_values())
-      if (IncValue == &PN)
-        return false;
+    if (llvm::is_contained(PN.incoming_values(), &PN))
+      return false;
 
   LLVM_DEBUG(dbgs() << "Merging: " << BB->getName() << " into "
                     << PredBB->getName() << "\n");
diff --git a/llvm/lib/Transforms/Utils/ScalarEvolutionExpander.cpp b/llvm/lib/Transforms/Utils/ScalarEvolutionExpander.cpp
index 6dbfb0b61fea2..518238d59e27e 100644
--- a/llvm/lib/Transforms/Utils/ScalarEvolutionExpander.cpp
+++ b/llvm/lib/Transforms/Utils/ScalarEvolutionExpander.cpp
@@ -2675,9 +2675,8 @@ bool isSafeToExpandAt(const SCEV *S, const Instruction *InsertionPoint,
     if (InsertionPoint->getParent()->getTerminator() == InsertionPoint)
       return true;
     if (const SCEVUnknown *U = dyn_cast<SCEVUnknown>(S))
-      for (const Value *V : InsertionPoint->operand_values())
-        if (V == U->getValue())
-          return true;
+      if (llvm::is_contained(InsertionPoint->operand_values(), U->getValue()))
+        return true;
   }
   return false;
 }
diff --git a/llvm/tools/llvm-xray/xray-graph-diff.cpp b/llvm/tools/llvm-xray/xray-graph-diff.cpp
index 11210e2004a7a..9ff84f22d8245 100644
--- a/llvm/tools/llvm-xray/xray-graph-diff.cpp
+++ b/llvm/tools/llvm-xray/xray-graph-diff.cpp
@@ -294,10 +294,7 @@ static Twine truncateString(const StringRef &S, size_t n) {
 }
 
 template <typename T> static bool containsNullptr(const T &Collection) {
-  for (const auto &E : Collection)
-    if (E == nullptr)
-      return true;
-  return false;
+  return llvm::is_contained(Collection, nullptr);
 }
 
 static std::string getLabel(const GraphDiffRenderer::GraphT::EdgeValueType &E,
diff --git a/llvm/tools/opt/opt.cpp b/llvm/tools/opt/opt.cpp
index 765581bc46209..e7ba330bb6179 100644
--- a/llvm/tools/opt/opt.cpp
+++ b/llvm/tools/opt/opt.cpp
@@ -484,9 +484,8 @@ static bool shouldPinPassToLegacyPM(StringRef Pass) {
       "amdgpu-unify-metadata",
       "amdgpu-printf-runtime-binding",
       "amdgpu-always-inline"};
-  for (const auto &P : PassNameExactToIgnore)
-    if (Pass == P)
-      return false;
+  if (llvm::is_contained(PassNameExactToIgnore, Pass))
+    return false;
 
   std::vector<StringRef> PassNamePrefix = {
       "x86-",  "xcore-", "wasm-",    "systemz-", "ppc-",    "nvvm-",   "nvptx-",
@@ -511,10 +510,7 @@ static bool shouldPinPassToLegacyPM(StringRef Pass) {
   for (const auto &P : PassNameContain)
     if (Pass.contains(P))
       return true;
-  for (const auto &P : PassNameExact)
-    if (Pass == P)
-      return true;
-  return false;
+  return llvm::is_contained(PassNameExact, Pass);
 }
 
 // For use in NPM transition.