diff --git a/include/llvm/Analysis/TargetTransformInfo.h b/include/llvm/Analysis/TargetTransformInfo.h
index ba8b7754e85..89c7c979262 100644
--- a/include/llvm/Analysis/TargetTransformInfo.h
+++ b/include/llvm/Analysis/TargetTransformInfo.h
@@ -21,11 +21,6 @@
 #ifndef LLVM_ANALYSIS_TARGETTRANSFORMINFO_H
 #define LLVM_ANALYSIS_TARGETTRANSFORMINFO_H
 
-#include "llvm/ADT/Optional.h"
-#include "llvm/Analysis/AssumptionCache.h"
-#include "llvm/Analysis/LoopInfo.h"
-#include "llvm/Analysis/ScalarEvolution.h"
-#include "llvm/IR/Dominators.h"
 #include "llvm/IR/Operator.h"
 #include "llvm/IR/PassManager.h"
 #include "llvm/Pass.h"
@@ -41,6 +36,7 @@ typedef unsigned ID;
 
 class AssumptionCache;
 class BlockFrequencyInfo;
+class DominatorTree;
 class BranchInst;
 class Function;
 class GlobalValue;
@@ -48,6 +44,7 @@ class IntrinsicInst;
 class LoadInst;
 class LoopAccessInfo;
 class Loop;
+class LoopInfo;
 class ProfileSummaryInfo;
 class SCEV;
 class ScalarEvolution;
@@ -57,6 +54,7 @@ class TargetLibraryInfo;
 class Type;
 class User;
 class Value;
+template <typename T> class Optional;
 
 /// Information about a load/store intrinsic defined by the target.
 struct MemIntrinsicInfo {
@@ -835,10 +833,10 @@ public:
   };
 
   /// \return The size of the cache level in bytes, if available.
-  llvm::Optional<unsigned> getCacheSize(CacheLevel Level) const;
+  Optional<unsigned> getCacheSize(CacheLevel Level) const;
 
   /// \return The associativity of the cache level, if available.
-  llvm::Optional<unsigned> getCacheAssociativity(CacheLevel Level) const;
+  Optional<unsigned> getCacheAssociativity(CacheLevel Level) const;
 
   /// \return How much before a load we should place the prefetch
   /// instruction.  This is currently measured in number of
@@ -1301,9 +1299,8 @@ public:
   virtual bool shouldConsiderAddressTypePromotion(
       const Instruction &I, bool &AllowPromotionWithoutCommonHeader) = 0;
   virtual unsigned getCacheLineSize() const = 0;
-  virtual llvm::Optional<unsigned> getCacheSize(CacheLevel Level) const = 0;
-  virtual llvm::Optional<unsigned>
-  getCacheAssociativity(CacheLevel Level) const = 0;
+  virtual Optional<unsigned> getCacheSize(CacheLevel Level) const = 0;
+  virtual Optional<unsigned> getCacheAssociativity(CacheLevel Level) const = 0;
 
   /// \return How much before a load we should place the prefetch
   /// instruction.  This is currently measured in number of
@@ -1679,11 +1676,10 @@ public:
         I, AllowPromotionWithoutCommonHeader);
   }
   unsigned getCacheLineSize() const override { return Impl.getCacheLineSize(); }
-  llvm::Optional<unsigned> getCacheSize(CacheLevel Level) const override {
+  Optional<unsigned> getCacheSize(CacheLevel Level) const override {
     return Impl.getCacheSize(Level);
   }
-  llvm::Optional<unsigned>
-  getCacheAssociativity(CacheLevel Level) const override {
+  Optional<unsigned> getCacheAssociativity(CacheLevel Level) const override {
     return Impl.getCacheAssociativity(Level);
   }
 
diff --git a/include/llvm/Transforms/Utils/LoopUtils.h b/include/llvm/Transforms/Utils/LoopUtils.h
index ba06d635ac2..e1b541f624e 100644
--- a/include/llvm/Transforms/Utils/LoopUtils.h
+++ b/include/llvm/Transforms/Utils/LoopUtils.h
@@ -21,6 +21,8 @@
 
 namespace llvm {
 
+template <typename T> class DomTreeNodeBase;
+using DomTreeNode = DomTreeNodeBase<BasicBlock>;
 class AliasSet;
 class AliasSetTracker;
 class BasicBlock;
diff --git a/lib/Target/AMDGPU/AMDGPUCodeGenPrepare.cpp b/lib/Target/AMDGPU/AMDGPUCodeGenPrepare.cpp
index e8c32cb346e..fef649f6b3f 100644
--- a/lib/Target/AMDGPU/AMDGPUCodeGenPrepare.cpp
+++ b/lib/Target/AMDGPU/AMDGPUCodeGenPrepare.cpp
@@ -28,6 +28,7 @@
 #include "llvm/IR/BasicBlock.h"
 #include "llvm/IR/Constants.h"
 #include "llvm/IR/DerivedTypes.h"
+#include "llvm/IR/Dominators.h"
 #include "llvm/IR/Function.h"
 #include "llvm/IR/IRBuilder.h"
 #include "llvm/IR/InstVisitor.h"
@@ -40,10 +41,10 @@
 #include "llvm/IR/Operator.h"
 #include "llvm/IR/Type.h"
 #include "llvm/IR/Value.h"
-#include "llvm/Transforms/Utils/IntegerDivision.h"
 #include "llvm/InitializePasses.h"
 #include "llvm/Pass.h"
 #include "llvm/Support/Casting.h"
+#include "llvm/Transforms/Utils/IntegerDivision.h"
 #include <cassert>
 #include <iterator>
 
diff --git a/lib/Target/ARM/MVEGatherScatterLowering.cpp b/lib/Target/ARM/MVEGatherScatterLowering.cpp
index e4f6d1200a8..580b5d5881f 100644
--- a/lib/Target/ARM/MVEGatherScatterLowering.cpp
+++ b/lib/Target/ARM/MVEGatherScatterLowering.cpp
@@ -15,26 +15,27 @@
 #include "ARM.h"
 #include "ARMBaseInstrInfo.h"
 #include "ARMSubtarget.h"
+#include "llvm/Analysis/LoopInfo.h"
 #include "llvm/Analysis/TargetTransformInfo.h"
 #include "llvm/CodeGen/TargetLowering.h"
 #include "llvm/CodeGen/TargetPassConfig.h"
 #include "llvm/CodeGen/TargetSubtargetInfo.h"
-#include "llvm/InitializePasses.h"
 #include "llvm/IR/BasicBlock.h"
 #include "llvm/IR/Constant.h"
 #include "llvm/IR/Constants.h"
 #include "llvm/IR/DerivedTypes.h"
 #include "llvm/IR/Function.h"
+#include "llvm/IR/IRBuilder.h"
 #include "llvm/IR/InstrTypes.h"
 #include "llvm/IR/Instruction.h"
 #include "llvm/IR/Instructions.h"
 #include "llvm/IR/IntrinsicInst.h"
 #include "llvm/IR/Intrinsics.h"
 #include "llvm/IR/IntrinsicsARM.h"
-#include "llvm/IR/IRBuilder.h"
 #include "llvm/IR/PatternMatch.h"
 #include "llvm/IR/Type.h"
 #include "llvm/IR/Value.h"
+#include "llvm/InitializePasses.h"
 #include "llvm/Pass.h"
 #include "llvm/Support/Casting.h"
 #include "llvm/Transforms/Utils/Local.h"
diff --git a/lib/Transforms/IPO/AttributorAttributes.cpp b/lib/Transforms/IPO/AttributorAttributes.cpp
index fb9a3e2e6f9..ee91aff67ee 100644
--- a/lib/Transforms/IPO/AttributorAttributes.cpp
+++ b/lib/Transforms/IPO/AttributorAttributes.cpp
@@ -18,6 +18,7 @@
 #include "llvm/Analysis/CaptureTracking.h"
 #include "llvm/Analysis/LazyValueInfo.h"
 #include "llvm/Analysis/MemoryBuiltins.h"
+#include "llvm/Analysis/ScalarEvolution.h"
 #include "llvm/Analysis/ValueTracking.h"
 #include "llvm/IR/IRBuilder.h"
 #include "llvm/IR/IntrinsicInst.h"
diff --git a/lib/Transforms/Scalar/WarnMissedTransforms.cpp b/lib/Transforms/Scalar/WarnMissedTransforms.cpp
index c8461fdc160..7c81e6352de 100644
--- a/lib/Transforms/Scalar/WarnMissedTransforms.cpp
+++ b/lib/Transforms/Scalar/WarnMissedTransforms.cpp
@@ -11,6 +11,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/Transforms/Scalar/WarnMissedTransforms.h"
+#include "llvm/Analysis/LoopInfo.h"
 #include "llvm/Analysis/OptimizationRemarkEmitter.h"
 #include "llvm/InitializePasses.h"
 #include "llvm/Transforms/Utils/LoopUtils.h"
diff --git a/unittests/Transforms/Utils/LoopUtilsTest.cpp b/unittests/Transforms/Utils/LoopUtilsTest.cpp
index 35fd97a50d0..847049d8c29 100644
--- a/unittests/Transforms/Utils/LoopUtilsTest.cpp
+++ b/unittests/Transforms/Utils/LoopUtilsTest.cpp
@@ -7,7 +7,10 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/Transforms/Utils/LoopUtils.h"
+#include "llvm/Analysis/AssumptionCache.h"
+#include "llvm/Analysis/ScalarEvolution.h"
 #include "llvm/AsmParser/Parser.h"
+#include "llvm/IR/Dominators.h"
 #include "llvm/Support/SourceMgr.h"
 #include "gtest/gtest.h"