diff --git a/clang/lib/CodeGen/BackendUtil.cpp b/clang/lib/CodeGen/BackendUtil.cpp
--- a/clang/lib/CodeGen/BackendUtil.cpp
+++ b/clang/lib/CodeGen/BackendUtil.cpp
@@ -1069,16 +1069,16 @@
     DwoOS->keep();
 }
 
-static PassBuilder::OptimizationLevel mapToLevel(const CodeGenOptions &Opts) {
+static OptimizationLevel mapToLevel(const CodeGenOptions &Opts) {
   switch (Opts.OptimizationLevel) {
   default:
     llvm_unreachable("Invalid optimization level!");
 
   case 0:
-    return PassBuilder::OptimizationLevel::O0;
+    return OptimizationLevel::O0;
 
   case 1:
-    return PassBuilder::OptimizationLevel::O1;
+    return OptimizationLevel::O1;
 
   case 2:
     switch (Opts.OptimizeSize) {
@@ -1086,17 +1086,17 @@
       llvm_unreachable("Invalid optimization level for size!");
 
     case 0:
-      return PassBuilder::OptimizationLevel::O2;
+      return OptimizationLevel::O2;
 
     case 1:
-      return PassBuilder::OptimizationLevel::Os;
+      return OptimizationLevel::Os;
 
     case 2:
-      return PassBuilder::OptimizationLevel::Oz;
+      return OptimizationLevel::Oz;
     }
 
   case 3:
-    return PassBuilder::OptimizationLevel::O3;
+    return OptimizationLevel::O3;
   }
 }
 
@@ -1104,7 +1104,7 @@
                           const CodeGenOptions &CodeGenOpts,
                           const LangOptions &LangOpts, PassBuilder &PB) {
   PB.registerOptimizerLastEPCallback([&](ModulePassManager &MPM,
-                                         PassBuilder::OptimizationLevel Level) {
+                                         OptimizationLevel Level) {
     if (CodeGenOpts.hasSanitizeCoverage()) {
       auto SancovOpts = getSancovOptsFromCGOpts(CodeGenOpts);
       MPM.addPass(ModuleSanitizerCoveragePass(
@@ -1122,7 +1122,7 @@
         FunctionPassManager FPM;
         FPM.addPass(
             MemorySanitizerPass({TrackOrigins, Recover, CompileKernel}));
-        if (Level != PassBuilder::OptimizationLevel::O0) {
+        if (Level != OptimizationLevel::O0) {
           // MemorySanitizer inserts complex instrumentation that mostly
           // follows the logic of the original code, but operates on
           // "shadow" values. It can benefit from re-running some
@@ -1325,26 +1325,26 @@
   if (!CodeGenOpts.DisableLLVMPasses) {
     // Map our optimization levels into one of the distinct levels used to
     // configure the pipeline.
-    PassBuilder::OptimizationLevel Level = mapToLevel(CodeGenOpts);
+    OptimizationLevel Level = mapToLevel(CodeGenOpts);
 
     bool IsThinLTO = CodeGenOpts.PrepareForThinLTO;
     bool IsLTO = CodeGenOpts.PrepareForLTO;
 
     if (LangOpts.ObjCAutoRefCount) {
       PB.registerPipelineStartEPCallback(
-          [](ModulePassManager &MPM, PassBuilder::OptimizationLevel Level) {
-            if (Level != PassBuilder::OptimizationLevel::O0)
+          [](ModulePassManager &MPM, OptimizationLevel Level) {
+            if (Level != OptimizationLevel::O0)
               MPM.addPass(
                   createModuleToFunctionPassAdaptor(ObjCARCExpandPass()));
           });
       PB.registerPipelineEarlySimplificationEPCallback(
-          [](ModulePassManager &MPM, PassBuilder::OptimizationLevel Level) {
-            if (Level != PassBuilder::OptimizationLevel::O0)
+          [](ModulePassManager &MPM, OptimizationLevel Level) {
+            if (Level != OptimizationLevel::O0)
               MPM.addPass(ObjCARCAPElimPass());
           });
       PB.registerScalarOptimizerLateEPCallback(
-          [](FunctionPassManager &FPM, PassBuilder::OptimizationLevel Level) {
-            if (Level != PassBuilder::OptimizationLevel::O0)
+          [](FunctionPassManager &FPM, OptimizationLevel Level) {
+            if (Level != OptimizationLevel::O0)
               FPM.addPass(ObjCARCOptPass());
           });
     }
@@ -1357,7 +1357,7 @@
     // vtables so that codegen doesn't complain.
     if (IsThinLTOPostLink)
       PB.registerPipelineStartEPCallback(
-          [](ModulePassManager &MPM, PassBuilder::OptimizationLevel Level) {
+          [](ModulePassManager &MPM, OptimizationLevel Level) {
             MPM.addPass(LowerTypeTestsPass(/*ExportSummary=*/nullptr,
                                            /*ImportSummary=*/nullptr,
                                            /*DropTypeTests=*/true));
@@ -1368,12 +1368,12 @@
         CodeGenOpts.InstrumentFunctionsAfterInlining ||
         CodeGenOpts.InstrumentForProfiling) {
       PB.registerPipelineStartEPCallback(
-          [](ModulePassManager &MPM, PassBuilder::OptimizationLevel Level) {
+          [](ModulePassManager &MPM, OptimizationLevel Level) {
             MPM.addPass(createModuleToFunctionPassAdaptor(
                 EntryExitInstrumenterPass(/*PostInlining=*/false)));
           });
       PB.registerOptimizerLastEPCallback(
-          [](ModulePassManager &MPM, PassBuilder::OptimizationLevel Level) {
+          [](ModulePassManager &MPM, OptimizationLevel Level) {
             MPM.addPass(createModuleToFunctionPassAdaptor(
                 EntryExitInstrumenterPass(/*PostInlining=*/true)));
           });
@@ -1383,7 +1383,7 @@
     // of the pipeline.
     if (LangOpts.Sanitize.has(SanitizerKind::LocalBounds))
       PB.registerScalarOptimizerLateEPCallback(
-          [](FunctionPassManager &FPM, PassBuilder::OptimizationLevel Level) {
+          [](FunctionPassManager &FPM, OptimizationLevel Level) {
             FPM.addPass(BoundsCheckingPass());
           });
 
@@ -1394,15 +1394,13 @@
 
     if (Optional<GCOVOptions> Options = getGCOVOptions(CodeGenOpts, LangOpts))
       PB.registerPipelineStartEPCallback(
-          [Options](ModulePassManager &MPM,
-                    PassBuilder::OptimizationLevel Level) {
+          [Options](ModulePassManager &MPM, OptimizationLevel Level) {
             MPM.addPass(GCOVProfilerPass(*Options));
           });
     if (Optional<InstrProfOptions> Options =
             getInstrProfOptions(CodeGenOpts, LangOpts))
       PB.registerPipelineStartEPCallback(
-          [Options](ModulePassManager &MPM,
-                    PassBuilder::OptimizationLevel Level) {
+          [Options](ModulePassManager &MPM, OptimizationLevel Level) {
             MPM.addPass(InstrProfiling(*Options, false));
           });
 
diff --git a/llvm/examples/Bye/Bye.cpp b/llvm/examples/Bye/Bye.cpp
--- a/llvm/examples/Bye/Bye.cpp
+++ b/llvm/examples/Bye/Bye.cpp
@@ -55,8 +55,7 @@
   return {LLVM_PLUGIN_API_VERSION, "Bye", LLVM_VERSION_STRING,
           [](PassBuilder &PB) {
             PB.registerVectorizerStartEPCallback(
-                [](llvm::FunctionPassManager &PM,
-                   llvm::PassBuilder::OptimizationLevel Level) {
+                [](llvm::FunctionPassManager &PM, OptimizationLevel Level) {
                   PM.addPass(Bye());
                 });
             PB.registerPipelineParsingCallback(
diff --git a/llvm/include/llvm/Passes/OptimizationLevel.h b/llvm/include/llvm/Passes/OptimizationLevel.h
new file mode 100644
--- /dev/null
+++ b/llvm/include/llvm/Passes/OptimizationLevel.h
@@ -0,0 +1,127 @@
+//===-------- LLVM-provided High-Level Optimization levels -*- C++ -*------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+/// \file
+///
+/// This header enumerates the LLVM-provided high-level optimization levels.
+/// Each level has a specific goal and rationale.
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_PASSES_OPTIMIZATIONLEVEL_H
+#define LLVM_PASSES_OPTIMIZATIONLEVEL_H
+
+#include <assert.h>
+
+namespace llvm {
+
+class OptimizationLevel final {
+  unsigned SpeedLevel = 2;
+  unsigned SizeLevel = 0;
+  OptimizationLevel(unsigned SpeedLevel, unsigned SizeLevel)
+      : SpeedLevel(SpeedLevel), SizeLevel(SizeLevel) {
+    // Check that only valid combinations are passed.
+    assert(SpeedLevel <= 3 &&
+           "Optimization level for speed should be 0, 1, 2, or 3");
+    assert(SizeLevel <= 2 &&
+           "Optimization level for size should be 0, 1, or 2");
+    assert((SizeLevel == 0 || SpeedLevel == 2) &&
+           "Optimize for size should be encoded with speedup level == 2");
+  }
+
+public:
+  OptimizationLevel() = default;
+  /// Disable as many optimizations as possible. This doesn't completely
+  /// disable the optimizer in all cases, for example always_inline functions
+  /// can be required to be inlined for correctness.
+  static const OptimizationLevel O0;
+
+  /// Optimize quickly without destroying debuggability.
+  ///
+  /// This level is tuned to produce a result from the optimizer as quickly
+  /// as possible and to avoid destroying debuggability. This tends to result
+  /// in a very good development mode where the compiled code will be
+  /// immediately executed as part of testing. As a consequence, where
+  /// possible, we would like to produce efficient-to-execute code, but not
+  /// if it significantly slows down compilation or would prevent even basic
+  /// debugging of the resulting binary.
+  ///
+  /// As an example, complex loop transformations such as versioning,
+  /// vectorization, or fusion don't make sense here due to the degree to
+  /// which the executed code differs from the source code, and the compile
+  /// time cost.
+  static const OptimizationLevel O1;
+  /// Optimize for fast execution as much as possible without triggering
+  /// significant incremental compile time or code size growth.
+  ///
+  /// The key idea is that optimizations at this level should "pay for
+  /// themselves". So if an optimization increases compile time by 5% or
+  /// increases code size by 5% for a particular benchmark, that benchmark
+  /// should also be one which sees a 5% runtime improvement. If the compile
+  /// time or code size penalties happen on average across a diverse range of
+  /// LLVM users' benchmarks, then the improvements should as well.
+  ///
+  /// And no matter what, the compile time needs to not grow superlinearly
+  /// with the size of input to LLVM so that users can control the runtime of
+  /// the optimizer in this mode.
+  ///
+  /// This is expected to be a good default optimization level for the vast
+  /// majority of users.
+  static const OptimizationLevel O2;
+  /// Optimize for fast execution as much as possible.
+  ///
+  /// This mode is significantly more aggressive in trading off compile time
+  /// and code size to get execution time improvements. The core idea is that
+  /// this mode should include any optimization that helps execution time on
+  /// balance across a diverse collection of benchmarks, even if it increases
+  /// code size or compile time for some benchmarks without corresponding
+  /// improvements to execution time.
+  ///
+  /// Despite being willing to trade more compile time off to get improved
+  /// execution time, this mode still tries to avoid superlinear growth in
+  /// order to make even significantly slower compile times at least scale
+  /// reasonably. This does not preclude very substantial constant factor
+  /// costs though.
+  static const OptimizationLevel O3;
+  /// Similar to \c O2 but tries to optimize for small code size instead of
+  /// fast execution without triggering significant incremental execution
+  /// time slowdowns.
+  ///
+  /// The logic here is exactly the same as \c O2, but with code size and
+  /// execution time metrics swapped.
+  ///
+  /// A consequence of the different core goal is that this should in general
+  /// produce substantially smaller executables that still run in
+  /// a reasonable amount of time.
+  static const OptimizationLevel Os;
+  /// A very specialized mode that will optimize for code size at any and all
+  /// costs.
+  ///
+  /// This is useful primarily when there are absolute size limitations and
+  /// any effort taken to reduce the size is worth it regardless of the
+  /// execution time impact. You should expect this level to produce rather
+  /// slow, but very small, code.
+  static const OptimizationLevel Oz;
+
+  bool isOptimizingForSpeed() const { return SizeLevel == 0 && SpeedLevel > 0; }
+
+  bool isOptimizingForSize() const { return SizeLevel > 0; }
+
+  bool operator==(const OptimizationLevel &Other) const {
+    return SizeLevel == Other.SizeLevel && SpeedLevel == Other.SpeedLevel;
+  }
+  bool operator!=(const OptimizationLevel &Other) const {
+    return SizeLevel != Other.SizeLevel || SpeedLevel != Other.SpeedLevel;
+  }
+
+  unsigned getSpeedupLevel() const { return SpeedLevel; }
+
+  unsigned getSizeLevel() const { return SizeLevel; }
+};
+} // namespace llvm
+
+#endif 
diff --git a/llvm/include/llvm/Passes/PassBuilder.h b/llvm/include/llvm/Passes/PassBuilder.h
--- a/llvm/include/llvm/Passes/PassBuilder.h
+++ b/llvm/include/llvm/Passes/PassBuilder.h
@@ -18,6 +18,7 @@
 #include "llvm/ADT/Optional.h"
 #include "llvm/Analysis/CGSCCPassManager.h"
 #include "llvm/IR/PassManager.h"
+#include "llvm/Passes/OptimizationLevel.h"
 #include "llvm/Support/Error.h"
 #include "llvm/Support/raw_ostream.h"
 #include "llvm/Transforms/IPO/Inliner.h"
@@ -150,116 +151,6 @@
     std::vector<PipelineElement> InnerPipeline;
   };
 
-  /// LLVM-provided high-level optimization levels.
-  ///
-  /// This enumerates the LLVM-provided high-level optimization levels. Each
-  /// level has a specific goal and rationale.
-  class OptimizationLevel final {
-    unsigned SpeedLevel = 2;
-    unsigned SizeLevel = 0;
-    OptimizationLevel(unsigned SpeedLevel, unsigned SizeLevel)
-        : SpeedLevel(SpeedLevel), SizeLevel(SizeLevel) {
-      // Check that only valid combinations are passed.
-      assert(SpeedLevel <= 3 &&
-             "Optimization level for speed should be 0, 1, 2, or 3");
-      assert(SizeLevel <= 2 &&
-             "Optimization level for size should be 0, 1, or 2");
-      assert((SizeLevel == 0 || SpeedLevel == 2) &&
-             "Optimize for size should be encoded with speedup level == 2");
-    }
-
-  public:
-    OptimizationLevel() = default;
-    /// Disable as many optimizations as possible. This doesn't completely
-    /// disable the optimizer in all cases, for example always_inline functions
-    /// can be required to be inlined for correctness.
-    static const OptimizationLevel O0;
-
-    /// Optimize quickly without destroying debuggability.
-    ///
-    /// This level is tuned to produce a result from the optimizer as quickly
-    /// as possible and to avoid destroying debuggability. This tends to result
-    /// in a very good development mode where the compiled code will be
-    /// immediately executed as part of testing. As a consequence, where
-    /// possible, we would like to produce efficient-to-execute code, but not
-    /// if it significantly slows down compilation or would prevent even basic
-    /// debugging of the resulting binary.
-    ///
-    /// As an example, complex loop transformations such as versioning,
-    /// vectorization, or fusion don't make sense here due to the degree to
-    /// which the executed code differs from the source code, and the compile
-    /// time cost.
-    static const OptimizationLevel O1;
-    /// Optimize for fast execution as much as possible without triggering
-    /// significant incremental compile time or code size growth.
-    ///
-    /// The key idea is that optimizations at this level should "pay for
-    /// themselves". So if an optimization increases compile time by 5% or
-    /// increases code size by 5% for a particular benchmark, that benchmark
-    /// should also be one which sees a 5% runtime improvement. If the compile
-    /// time or code size penalties happen on average across a diverse range of
-    /// LLVM users' benchmarks, then the improvements should as well.
-    ///
-    /// And no matter what, the compile time needs to not grow superlinearly
-    /// with the size of input to LLVM so that users can control the runtime of
-    /// the optimizer in this mode.
-    ///
-    /// This is expected to be a good default optimization level for the vast
-    /// majority of users.
-    static const OptimizationLevel O2;
-    /// Optimize for fast execution as much as possible.
-    ///
-    /// This mode is significantly more aggressive in trading off compile time
-    /// and code size to get execution time improvements. The core idea is that
-    /// this mode should include any optimization that helps execution time on
-    /// balance across a diverse collection of benchmarks, even if it increases
-    /// code size or compile time for some benchmarks without corresponding
-    /// improvements to execution time.
-    ///
-    /// Despite being willing to trade more compile time off to get improved
-    /// execution time, this mode still tries to avoid superlinear growth in
-    /// order to make even significantly slower compile times at least scale
-    /// reasonably. This does not preclude very substantial constant factor
-    /// costs though.
-    static const OptimizationLevel O3;
-    /// Similar to \c O2 but tries to optimize for small code size instead of
-    /// fast execution without triggering significant incremental execution
-    /// time slowdowns.
-    ///
-    /// The logic here is exactly the same as \c O2, but with code size and
-    /// execution time metrics swapped.
-    ///
-    /// A consequence of the different core goal is that this should in general
-    /// produce substantially smaller executables that still run in
-    /// a reasonable amount of time.
-    static const OptimizationLevel Os;
-    /// A very specialized mode that will optimize for code size at any and all
-    /// costs.
-    ///
-    /// This is useful primarily when there are absolute size limitations and
-    /// any effort taken to reduce the size is worth it regardless of the
-    /// execution time impact. You should expect this level to produce rather
-    /// slow, but very small, code.
-    static const OptimizationLevel Oz;
-
-    bool isOptimizingForSpeed() const {
-      return SizeLevel == 0 && SpeedLevel > 0;
-    }
-
-    bool isOptimizingForSize() const { return SizeLevel > 0; }
-
-    bool operator==(const OptimizationLevel &Other) const {
-      return SizeLevel == Other.SizeLevel && SpeedLevel == Other.SpeedLevel;
-    }
-    bool operator!=(const OptimizationLevel &Other) const {
-      return SizeLevel != Other.SizeLevel || SpeedLevel != Other.SpeedLevel;
-    }
-
-    unsigned getSpeedupLevel() const { return SpeedLevel; }
-
-    unsigned getSizeLevel() const { return SizeLevel; }
-  };
-
   explicit PassBuilder(TargetMachine *TM = nullptr,
                        PipelineTuningOptions PTO = PipelineTuningOptions(),
                        Optional<PGOOptions> PGOOpt = None,
diff --git a/llvm/lib/LTO/LTOBackend.cpp b/llvm/lib/LTO/LTOBackend.cpp
--- a/llvm/lib/LTO/LTOBackend.cpp
+++ b/llvm/lib/LTO/LTOBackend.cpp
@@ -269,22 +269,22 @@
   if (!Conf.DisableVerify)
     MPM.addPass(VerifierPass());
 
-  PassBuilder::OptimizationLevel OL;
+  OptimizationLevel OL;
 
   switch (OptLevel) {
   default:
     llvm_unreachable("Invalid optimization level");
   case 0:
-    OL = PassBuilder::OptimizationLevel::O0;
+    OL = OptimizationLevel::O0;
     break;
   case 1:
-    OL = PassBuilder::OptimizationLevel::O1;
+    OL = OptimizationLevel::O1;
     break;
   case 2:
-    OL = PassBuilder::OptimizationLevel::O2;
+    OL = OptimizationLevel::O2;
     break;
   case 3:
-    OL = PassBuilder::OptimizationLevel::O3;
+    OL = OptimizationLevel::O3;
     break;
   }
 
diff --git a/llvm/lib/LTO/ThinLTOCodeGenerator.cpp b/llvm/lib/LTO/ThinLTOCodeGenerator.cpp
--- a/llvm/lib/LTO/ThinLTOCodeGenerator.cpp
+++ b/llvm/lib/LTO/ThinLTOCodeGenerator.cpp
@@ -303,22 +303,22 @@
 
   ModulePassManager MPM;
 
-  PassBuilder::OptimizationLevel OL;
+  OptimizationLevel OL;
 
   switch (OptLevel) {
   default:
     llvm_unreachable("Invalid optimization level");
   case 0:
-    OL = PassBuilder::OptimizationLevel::O0;
+    OL = OptimizationLevel::O0;
     break;
   case 1:
-    OL = PassBuilder::OptimizationLevel::O1;
+    OL = OptimizationLevel::O1;
     break;
   case 2:
-    OL = PassBuilder::OptimizationLevel::O2;
+    OL = OptimizationLevel::O2;
     break;
   case 3:
-    OL = PassBuilder::OptimizationLevel::O3;
+    OL = OptimizationLevel::O3;
     break;
   }
 
diff --git a/llvm/lib/Passes/PassBuilder.cpp b/llvm/lib/Passes/PassBuilder.cpp
--- a/llvm/lib/Passes/PassBuilder.cpp
+++ b/llvm/lib/Passes/PassBuilder.cpp
@@ -319,22 +319,22 @@
 extern cl::opt<int> PreInlineThreshold;
 } // namespace llvm
 
-const PassBuilder::OptimizationLevel PassBuilder::OptimizationLevel::O0 = {
+const OptimizationLevel OptimizationLevel::O0 = {
     /*SpeedLevel*/ 0,
     /*SizeLevel*/ 0};
-const PassBuilder::OptimizationLevel PassBuilder::OptimizationLevel::O1 = {
+const OptimizationLevel OptimizationLevel::O1 = {
     /*SpeedLevel*/ 1,
     /*SizeLevel*/ 0};
-const PassBuilder::OptimizationLevel PassBuilder::OptimizationLevel::O2 = {
+const OptimizationLevel OptimizationLevel::O2 = {
     /*SpeedLevel*/ 2,
     /*SizeLevel*/ 0};
-const PassBuilder::OptimizationLevel PassBuilder::OptimizationLevel::O3 = {
+const OptimizationLevel OptimizationLevel::O3 = {
     /*SpeedLevel*/ 3,
     /*SizeLevel*/ 0};
-const PassBuilder::OptimizationLevel PassBuilder::OptimizationLevel::Os = {
+const OptimizationLevel OptimizationLevel::Os = {
     /*SpeedLevel*/ 2,
     /*SizeLevel*/ 1};
-const PassBuilder::OptimizationLevel PassBuilder::OptimizationLevel::Oz = {
+const OptimizationLevel OptimizationLevel::Oz = {
     /*SpeedLevel*/ 2,
     /*SizeLevel*/ 2};
 
@@ -475,8 +475,8 @@
   }
 }
 
-void PassBuilder::invokePeepholeEPCallbacks(
-    FunctionPassManager &FPM, PassBuilder::OptimizationLevel Level) {
+void PassBuilder::invokePeepholeEPCallbacks(FunctionPassManager &FPM,
+                                            OptimizationLevel Level) {
   for (auto &C : PeepholeEPCallbacks)
     C(FPM, Level);
 }
@@ -874,9 +874,8 @@
 }
 
 void PassBuilder::addPGOInstrPasses(ModulePassManager &MPM,
-                                    PassBuilder::OptimizationLevel Level,
-                                    bool RunProfileGen, bool IsCS,
-                                    std::string ProfileFile,
+                                    OptimizationLevel Level, bool RunProfileGen,
+                                    bool IsCS, std::string ProfileFile,
                                     std::string ProfileRemappingFile) {
   assert(Level != OptimizationLevel::O0 && "Not expecting O0 here!");
   if (!IsCS && !DisablePreInliner) {
@@ -963,8 +962,7 @@
   MPM.addPass(InstrProfiling(Options, IsCS));
 }
 
-static InlineParams
-getInlineParamsFromOptLevel(PassBuilder::OptimizationLevel Level) {
+static InlineParams getInlineParamsFromOptLevel(OptimizationLevel Level) {
   return getInlineParams(Level.getSpeedupLevel(), Level.getSizeLevel());
 }
 
diff --git a/llvm/lib/Target/AMDGPU/AMDGPUTargetMachine.cpp b/llvm/lib/Target/AMDGPU/AMDGPUTargetMachine.cpp
--- a/llvm/lib/Target/AMDGPU/AMDGPUTargetMachine.cpp
+++ b/llvm/lib/Target/AMDGPU/AMDGPUTargetMachine.cpp
@@ -690,19 +690,18 @@
   });
 
   PB.registerPipelineStartEPCallback(
-      [this](ModulePassManager &PM, PassBuilder::OptimizationLevel Level) {
+      [this](ModulePassManager &PM, OptimizationLevel Level) {
         FunctionPassManager FPM;
         FPM.addPass(AMDGPUPropagateAttributesEarlyPass(*this));
         FPM.addPass(AMDGPUUseNativeCallsPass());
-        if (EnableLibCallSimplify &&
-            Level != PassBuilder::OptimizationLevel::O0)
+        if (EnableLibCallSimplify && Level != OptimizationLevel::O0)
           FPM.addPass(AMDGPUSimplifyLibCallsPass(*this));
         PM.addPass(createModuleToFunctionPassAdaptor(std::move(FPM)));
       });
 
   PB.registerPipelineEarlySimplificationEPCallback(
-      [this](ModulePassManager &PM, PassBuilder::OptimizationLevel Level) {
-        if (Level == PassBuilder::OptimizationLevel::O0)
+      [this](ModulePassManager &PM, OptimizationLevel Level) {
+        if (Level == OptimizationLevel::O0)
           return;
 
         PM.addPass(AMDGPUUnifyMetadataPass());
@@ -720,8 +719,8 @@
       });
 
   PB.registerCGSCCOptimizerLateEPCallback(
-      [this](CGSCCPassManager &PM, PassBuilder::OptimizationLevel Level) {
-        if (Level == PassBuilder::OptimizationLevel::O0)
+      [this](CGSCCPassManager &PM, OptimizationLevel Level) {
+        if (Level == OptimizationLevel::O0)
           return;
 
         FunctionPassManager FPM;
@@ -734,7 +733,7 @@
         // anything, and before other cleanup optimizations.
         FPM.addPass(AMDGPULowerKernelAttributesPass());
 
-        if (Level != PassBuilder::OptimizationLevel::O0) {
+        if (Level != OptimizationLevel::O0) {
           // Promote alloca to vector before SROA and loop unroll. If we
           // manage to eliminate allocas before unroll we may choose to unroll
           // less.
diff --git a/llvm/lib/Target/BPF/BPFTargetMachine.cpp b/llvm/lib/Target/BPF/BPFTargetMachine.cpp
--- a/llvm/lib/Target/BPF/BPFTargetMachine.cpp
+++ b/llvm/lib/Target/BPF/BPFTargetMachine.cpp
@@ -124,18 +124,18 @@
 
 void BPFTargetMachine::registerPassBuilderCallbacks(PassBuilder &PB) {
   PB.registerPipelineStartEPCallback(
-      [=](ModulePassManager &MPM, PassBuilder::OptimizationLevel) {
+      [=](ModulePassManager &MPM, OptimizationLevel) {
         FunctionPassManager FPM;
         FPM.addPass(BPFAbstractMemberAccessPass(this));
         FPM.addPass(BPFPreserveDITypePass());
         MPM.addPass(createModuleToFunctionPassAdaptor(std::move(FPM)));
       });
   PB.registerPeepholeEPCallback([=](FunctionPassManager &FPM,
-                                    PassBuilder::OptimizationLevel Level) {
+                                    OptimizationLevel Level) {
     FPM.addPass(SimplifyCFGPass(SimplifyCFGOptions().hoistCommonInsts(true)));
   });
   PB.registerPipelineEarlySimplificationEPCallback(
-      [=](ModulePassManager &MPM, PassBuilder::OptimizationLevel) {
+      [=](ModulePassManager &MPM, OptimizationLevel) {
         MPM.addPass(BPFAdjustOptPass());
       });
 }
diff --git a/llvm/lib/Target/Hexagon/HexagonTargetMachine.cpp b/llvm/lib/Target/Hexagon/HexagonTargetMachine.cpp
--- a/llvm/lib/Target/Hexagon/HexagonTargetMachine.cpp
+++ b/llvm/lib/Target/Hexagon/HexagonTargetMachine.cpp
@@ -280,11 +280,11 @@
 
 void HexagonTargetMachine::registerPassBuilderCallbacks(PassBuilder &PB) {
   PB.registerLateLoopOptimizationsEPCallback(
-      [=](LoopPassManager &LPM, PassBuilder::OptimizationLevel Level) {
+      [=](LoopPassManager &LPM, OptimizationLevel Level) {
         LPM.addPass(HexagonLoopIdiomRecognitionPass());
       });
   PB.registerLoopOptimizerEndEPCallback(
-      [=](LoopPassManager &LPM, PassBuilder::OptimizationLevel Level) {
+      [=](LoopPassManager &LPM, OptimizationLevel Level) {
         LPM.addPass(HexagonVectorLoopCarriedReusePass());
       });
 }
diff --git a/llvm/lib/Target/NVPTX/NVPTXTargetMachine.cpp b/llvm/lib/Target/NVPTX/NVPTXTargetMachine.cpp
--- a/llvm/lib/Target/NVPTX/NVPTXTargetMachine.cpp
+++ b/llvm/lib/Target/NVPTX/NVPTXTargetMachine.cpp
@@ -225,7 +225,7 @@
       });
 
   PB.registerPipelineStartEPCallback(
-      [this](ModulePassManager &PM, PassBuilder::OptimizationLevel Level) {
+      [this](ModulePassManager &PM, OptimizationLevel Level) {
         FunctionPassManager FPM;
         FPM.addPass(NVVMReflectPass(Subtarget.getSmVersion()));
         // FIXME: NVVMIntrRangePass is causing numerical discrepancies,
diff --git a/llvm/tools/opt/NewPMDriver.cpp b/llvm/tools/opt/NewPMDriver.cpp
--- a/llvm/tools/opt/NewPMDriver.cpp
+++ b/llvm/tools/opt/NewPMDriver.cpp
@@ -173,58 +173,58 @@
 static void registerEPCallbacks(PassBuilder &PB) {
   if (tryParsePipelineText<FunctionPassManager>(PB, PeepholeEPPipeline))
     PB.registerPeepholeEPCallback(
-        [&PB](FunctionPassManager &PM, PassBuilder::OptimizationLevel Level) {
+        [&PB](FunctionPassManager &PM, OptimizationLevel Level) {
           ExitOnError Err("Unable to parse PeepholeEP pipeline: ");
           Err(PB.parsePassPipeline(PM, PeepholeEPPipeline));
         });
   if (tryParsePipelineText<LoopPassManager>(PB,
                                             LateLoopOptimizationsEPPipeline))
     PB.registerLateLoopOptimizationsEPCallback(
-        [&PB](LoopPassManager &PM, PassBuilder::OptimizationLevel Level) {
+        [&PB](LoopPassManager &PM, OptimizationLevel Level) {
           ExitOnError Err("Unable to parse LateLoopOptimizationsEP pipeline: ");
           Err(PB.parsePassPipeline(PM, LateLoopOptimizationsEPPipeline));
         });
   if (tryParsePipelineText<LoopPassManager>(PB, LoopOptimizerEndEPPipeline))
     PB.registerLoopOptimizerEndEPCallback(
-        [&PB](LoopPassManager &PM, PassBuilder::OptimizationLevel Level) {
+        [&PB](LoopPassManager &PM, OptimizationLevel Level) {
           ExitOnError Err("Unable to parse LoopOptimizerEndEP pipeline: ");
           Err(PB.parsePassPipeline(PM, LoopOptimizerEndEPPipeline));
         });
   if (tryParsePipelineText<FunctionPassManager>(PB,
                                                 ScalarOptimizerLateEPPipeline))
     PB.registerScalarOptimizerLateEPCallback(
-        [&PB](FunctionPassManager &PM, PassBuilder::OptimizationLevel Level) {
+        [&PB](FunctionPassManager &PM, OptimizationLevel Level) {
           ExitOnError Err("Unable to parse ScalarOptimizerLateEP pipeline: ");
           Err(PB.parsePassPipeline(PM, ScalarOptimizerLateEPPipeline));
         });
   if (tryParsePipelineText<CGSCCPassManager>(PB, CGSCCOptimizerLateEPPipeline))
     PB.registerCGSCCOptimizerLateEPCallback(
-        [&PB](CGSCCPassManager &PM, PassBuilder::OptimizationLevel Level) {
+        [&PB](CGSCCPassManager &PM, OptimizationLevel Level) {
           ExitOnError Err("Unable to parse CGSCCOptimizerLateEP pipeline: ");
           Err(PB.parsePassPipeline(PM, CGSCCOptimizerLateEPPipeline));
         });
   if (tryParsePipelineText<FunctionPassManager>(PB, VectorizerStartEPPipeline))
     PB.registerVectorizerStartEPCallback(
-        [&PB](FunctionPassManager &PM, PassBuilder::OptimizationLevel Level) {
+        [&PB](FunctionPassManager &PM, OptimizationLevel Level) {
           ExitOnError Err("Unable to parse VectorizerStartEP pipeline: ");
           Err(PB.parsePassPipeline(PM, VectorizerStartEPPipeline));
         });
   if (tryParsePipelineText<ModulePassManager>(PB, PipelineStartEPPipeline))
     PB.registerPipelineStartEPCallback(
-        [&PB](ModulePassManager &PM, PassBuilder::OptimizationLevel) {
+        [&PB](ModulePassManager &PM, OptimizationLevel) {
           ExitOnError Err("Unable to parse PipelineStartEP pipeline: ");
           Err(PB.parsePassPipeline(PM, PipelineStartEPPipeline));
         });
   if (tryParsePipelineText<ModulePassManager>(
           PB, PipelineEarlySimplificationEPPipeline))
     PB.registerPipelineEarlySimplificationEPCallback(
-        [&PB](ModulePassManager &PM, PassBuilder::OptimizationLevel) {
+        [&PB](ModulePassManager &PM, OptimizationLevel) {
           ExitOnError Err("Unable to parse EarlySimplification pipeline: ");
           Err(PB.parsePassPipeline(PM, PipelineEarlySimplificationEPPipeline));
         });
   if (tryParsePipelineText<FunctionPassManager>(PB, OptimizerLastEPPipeline))
     PB.registerOptimizerLastEPCallback(
-        [&PB](ModulePassManager &PM, PassBuilder::OptimizationLevel) {
+        [&PB](ModulePassManager &PM, OptimizationLevel) {
           ExitOnError Err("Unable to parse OptimizerLastEP pipeline: ");
           Err(PB.parsePassPipeline(PM, OptimizerLastEPPipeline));
         });
diff --git a/polly/include/polly/Canonicalization.h b/polly/include/polly/Canonicalization.h
--- a/polly/include/polly/Canonicalization.h
+++ b/polly/include/polly/Canonicalization.h
@@ -30,7 +30,7 @@
 
 llvm::FunctionPassManager
 buildCanonicalicationPassesForNPM(llvm::ModulePassManager &MPM,
-                                  llvm::PassBuilder::OptimizationLevel Level);
+                                  llvm::OptimizationLevel Level);
 
 } // namespace polly
 
diff --git a/polly/lib/Support/RegisterPasses.cpp b/polly/lib/Support/RegisterPasses.cpp
--- a/polly/lib/Support/RegisterPasses.cpp
+++ b/polly/lib/Support/RegisterPasses.cpp
@@ -474,7 +474,7 @@
 ///                     the analysis passes are added, skipping Polly itself.
 ///                     The IR may still be modified.
 static void buildCommonPollyPipeline(FunctionPassManager &PM,
-                                     PassBuilder::OptimizationLevel Level,
+                                     OptimizationLevel Level,
                                      bool EnableForOpt) {
   PassBuilder PB;
   ScopPassManager SPM;
@@ -574,7 +574,7 @@
 }
 
 static void buildEarlyPollyPipeline(ModulePassManager &MPM,
-                                    PassBuilder::OptimizationLevel Level) {
+                                    OptimizationLevel Level) {
   bool EnableForOpt =
       shouldEnablePollyForOptimization() && Level.isOptimizingForSpeed();
   if (!shouldEnablePollyForDiagnostic() && !EnableForOpt)
@@ -603,7 +603,7 @@
 }
 
 static void buildLatePollyPipeline(FunctionPassManager &PM,
-                                   PassBuilder::OptimizationLevel Level) {
+                                   OptimizationLevel Level) {
   bool EnableForOpt =
       shouldEnablePollyForOptimization() && Level.isOptimizingForSpeed();
   if (!shouldEnablePollyForDiagnostic() && !EnableForOpt)
diff --git a/polly/lib/Transform/Canonicalization.cpp b/polly/lib/Transform/Canonicalization.cpp
--- a/polly/lib/Transform/Canonicalization.cpp
+++ b/polly/lib/Transform/Canonicalization.cpp
@@ -64,7 +64,7 @@
 
 /// Adapted from llvm::PassBuilder::buildInlinerPipeline
 static ModuleInlinerWrapperPass
-buildInlinePasses(llvm::PassBuilder::OptimizationLevel Level) {
+buildInlinePasses(llvm::OptimizationLevel Level) {
   InlineParams IP = getInlineParams(200);
   ModuleInlinerWrapperPass MIWP(IP);
 
@@ -92,8 +92,9 @@
   return MIWP;
 }
 
-FunctionPassManager polly::buildCanonicalicationPassesForNPM(
-    llvm::ModulePassManager &MPM, llvm::PassBuilder::OptimizationLevel Level) {
+FunctionPassManager
+polly::buildCanonicalicationPassesForNPM(llvm::ModulePassManager &MPM,
+                                         llvm::OptimizationLevel Level) {
   FunctionPassManager FPM;
 
   bool UseMemSSA = true;
@@ -107,7 +108,7 @@
   FPM.addPass(ReassociatePass());
   {
     LoopPassManager LPM;
-    LPM.addPass(LoopRotatePass(Level != PassBuilder::OptimizationLevel::Oz));
+    LPM.addPass(LoopRotatePass(Level != OptimizationLevel::Oz));
     FPM.addPass(createFunctionToLoopPassAdaptor<LoopPassManager>(
         std::move(LPM), /*UseMemorySSA=*/false,
         /*UseBlockFrequencyInfo=*/false));