diff --git a/clang/lib/CodeGen/CGCleanup.cpp b/clang/lib/CodeGen/CGCleanup.cpp
--- a/clang/lib/CodeGen/CGCleanup.cpp
+++ b/clang/lib/CodeGen/CGCleanup.cpp
@@ -942,7 +942,7 @@
       // Append the prepared cleanup prologue from above.
       llvm::BasicBlock *NormalExit = Builder.GetInsertBlock();
       for (unsigned I = 0, E = InstsToAppend.size(); I != E; ++I)
-        NormalExit->getInstList().push_back(InstsToAppend[I]);
+        InstsToAppend[I]->insertAt(NormalExit, NormalExit->end());
 
       // Optimistically hope that any fixups will continue falling through.
       for (unsigned I = FixupDepth, E = EHStack.getNumBranchFixups();
diff --git a/llvm/include/llvm/IR/IRBuilder.h b/llvm/include/llvm/IR/IRBuilder.h
--- a/llvm/include/llvm/IR/IRBuilder.h
+++ b/llvm/include/llvm/IR/IRBuilder.h
@@ -65,7 +65,8 @@
   virtual void InsertHelper(Instruction *I, const Twine &Name,
                             BasicBlock *BB,
                             BasicBlock::iterator InsertPt) const {
-    if (BB) BB->getInstList().insert(InsertPt, I);
+    if (BB)
+      I->insertAt(BB, InsertPt);
     I->setName(Name);
   }
 };
diff --git a/llvm/include/llvm/Transforms/InstCombine/InstCombiner.h b/llvm/include/llvm/Transforms/InstCombine/InstCombiner.h
--- a/llvm/include/llvm/Transforms/InstCombine/InstCombiner.h
+++ b/llvm/include/llvm/Transforms/InstCombine/InstCombiner.h
@@ -397,7 +397,7 @@
     assert(New && !New->getParent() &&
            "New instruction already inserted into a basic block!");
     BasicBlock *BB = Old.getParent();
-    BB->getInstList().insert(Old.getIterator(), New); // Insert inst
+    New->insertAt(BB, Old.getIterator()); // Insert inst
     Worklist.push(New);
     return New;
   }
diff --git a/llvm/include/llvm/Transforms/Utils/BasicBlockUtils.h b/llvm/include/llvm/Transforms/Utils/BasicBlockUtils.h
--- a/llvm/include/llvm/Transforms/Utils/BasicBlockUtils.h
+++ b/llvm/include/llvm/Transforms/Utils/BasicBlockUtils.h
@@ -121,8 +121,8 @@
 /// Copies DebugLoc from BI to I, if I doesn't already have a DebugLoc. The
 /// original instruction is deleted and BI is updated to point to the new
 /// instruction.
-void ReplaceInstWithInst(BasicBlock::InstListType &BIL,
-                         BasicBlock::iterator &BI, Instruction *I);
+void ReplaceInstWithInst(BasicBlock *BB, BasicBlock::iterator &BI,
+                         Instruction *I);
 
 /// Replace the instruction specified by From with the instruction specified by
 /// To. Copies DebugLoc from BI to I, if I doesn't already have a DebugLoc.
diff --git a/llvm/lib/AsmParser/LLParser.cpp b/llvm/lib/AsmParser/LLParser.cpp
--- a/llvm/lib/AsmParser/LLParser.cpp
+++ b/llvm/lib/AsmParser/LLParser.cpp
@@ -6166,7 +6166,7 @@
       llvm_unreachable("Unknown parseInstruction result!");
     case InstError: return true;
     case InstNormal:
-      BB->getInstList().push_back(Inst);
+      Inst->insertAt(BB, BB->end());
 
       // With a normal result, we check to see if the instruction is followed by
       // a comma and metadata.
@@ -6175,7 +6175,7 @@
           return true;
       break;
     case InstExtraComma:
-      BB->getInstList().push_back(Inst);
+      Inst->insertAt(BB, BB->end());
 
       // If the instruction parser ate an extra comma at the end of it, it
       // *must* be followed by metadata.
diff --git a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
--- a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
+++ b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
@@ -4840,7 +4840,7 @@
         if (Temp) {
           InstructionList.push_back(Temp);
           assert(CurBB && "No current BB?");
-          CurBB->getInstList().push_back(Temp);
+          Temp->insertAt(CurBB, CurBB->end());
         }
       } else {
         auto CastOp = (Instruction::CastOps)Opc;
@@ -6088,7 +6088,7 @@
         // Before weak cmpxchgs existed, the instruction simply returned the
         // value loaded from memory, so bitcode files from that era will be
         // expecting the first component of a modern cmpxchg.
-        CurBB->getInstList().push_back(I);
+        I->insertAt(CurBB, CurBB->end());
         I = ExtractValueInst::Create(I, 0);
         ResTypeID = CmpTypeID;
       } else {
@@ -6412,7 +6412,7 @@
       I->deleteValue();
       return error("Operand bundles found with no consumer");
     }
-    CurBB->getInstList().push_back(I);
+    I->insertAt(CurBB, CurBB->end());
 
     // If this was a terminator instruction, move to the next block.
     if (I->isTerminator()) {
diff --git a/llvm/lib/CodeGen/WinEHPrepare.cpp b/llvm/lib/CodeGen/WinEHPrepare.cpp
--- a/llvm/lib/CodeGen/WinEHPrepare.cpp
+++ b/llvm/lib/CodeGen/WinEHPrepare.cpp
@@ -1212,8 +1212,8 @@
       BranchInst *Goto = cast<BranchInst>(IncomingBlock->getTerminator());
       Goto->removeFromParent();
       CatchRet->removeFromParent();
-      IncomingBlock->getInstList().push_back(CatchRet);
-      NewBlock->getInstList().push_back(Goto);
+      CatchRet->insertAt(IncomingBlock, IncomingBlock->end());
+      Goto->insertAt(NewBlock, NewBlock->end());
       Goto->setSuccessor(0, PHIBlock);
       CatchRet->setSuccessor(NewBlock);
       // Update the color mapping for the newly split edge.
diff --git a/llvm/lib/IR/Instruction.cpp b/llvm/lib/IR/Instruction.cpp
--- a/llvm/lib/IR/Instruction.cpp
+++ b/llvm/lib/IR/Instruction.cpp
@@ -28,7 +28,7 @@
   if (InsertBefore) {
     BasicBlock *BB = InsertBefore->getParent();
     assert(BB && "Instruction to insert before is not in a basic block!");
-    BB->getInstList().insert(InsertBefore->getIterator(), this);
+    insertAt(BB, InsertBefore->getIterator());
   }
 }
 
@@ -38,7 +38,7 @@
 
   // append this instruction into the basic block
   assert(InsertAtEnd && "Basic block to append to may not be NULL!");
-  InsertAtEnd->getInstList().push_back(this);
+  insertAt(InsertAtEnd, InsertAtEnd->end());
 }
 
 Instruction::~Instruction() {
@@ -85,14 +85,13 @@
 /// Insert an unlinked instruction into a basic block immediately before the
 /// specified instruction.
 void Instruction::insertBefore(Instruction *InsertPos) {
-  InsertPos->getParent()->getInstList().insert(InsertPos->getIterator(), this);
+  insertAt(InsertPos->getParent(), InsertPos->getIterator());
 }
 
 /// Insert an unlinked instruction into a basic block immediately after the
 /// specified instruction.
 void Instruction::insertAfter(Instruction *InsertPos) {
-  InsertPos->getParent()->getInstList().insertAfter(InsertPos->getIterator(),
-                                                    this);
+  insertAt(InsertPos->getParent(), std::next(InsertPos->getIterator()));
 }
 
 BasicBlock::iterator Instruction::insertAt(BasicBlock *BB,
diff --git a/llvm/lib/IR/Instructions.cpp b/llvm/lib/IR/Instructions.cpp
--- a/llvm/lib/IR/Instructions.cpp
+++ b/llvm/lib/IR/Instructions.cpp
@@ -824,7 +824,7 @@
     MCall = CallInst::Create(MallocFunc, AllocSize, OpB, "malloccall");
     Result = MCall;
     if (Result->getType() != AllocPtrType) {
-      InsertAtEnd->getInstList().push_back(MCall);
+      MCall->insertAt(InsertAtEnd, InsertAtEnd->end());
       // Create a cast instruction to convert to the right type...
       Result = new BitCastInst(MCall, AllocPtrType, Name);
     }
@@ -2815,7 +2815,7 @@
                                      const Twine &Name,
                                      BasicBlock *InsertAtEnd) {
   UnaryOperator *Res = Create(Op, S, Name);
-  InsertAtEnd->getInstList().push_back(Res);
+  Res->insertAt(InsertAtEnd, InsertAtEnd->end());
   return Res;
 }
 
@@ -2946,7 +2946,7 @@
                                        const Twine &Name,
                                        BasicBlock *InsertAtEnd) {
   BinaryOperator *Res = Create(Op, S1, S2, Name);
-  InsertAtEnd->getInstList().push_back(Res);
+  Res->insertAt(InsertAtEnd, InsertAtEnd->end());
   return Res;
 }
 
diff --git a/llvm/lib/Transforms/IPO/IROutliner.cpp b/llvm/lib/Transforms/IPO/IROutliner.cpp
--- a/llvm/lib/Transforms/IPO/IROutliner.cpp
+++ b/llvm/lib/Transforms/IPO/IROutliner.cpp
@@ -1872,7 +1872,7 @@
       StoreInst *NewI = cast<StoreInst>(I->clone());
       NewI->setDebugLoc(DebugLoc());
       BasicBlock *OutputBB = VBBIt->second;
-      OutputBB->getInstList().push_back(NewI);
+      NewI->insertAt(OutputBB, OutputBB->end());
       LLVM_DEBUG(dbgs() << "Move store for instruction " << *I << " to "
                         << *OutputBB << "\n");
 
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineInternal.h b/llvm/lib/Transforms/InstCombine/InstCombineInternal.h
--- a/llvm/lib/Transforms/InstCombine/InstCombineInternal.h
+++ b/llvm/lib/Transforms/InstCombine/InstCombineInternal.h
@@ -388,7 +388,7 @@
     assert(New && !New->getParent() &&
            "New instruction already inserted into a basic block!");
     BasicBlock *BB = Old.getParent();
-    BB->getInstList().insert(Old.getIterator(), New); // Insert inst
+    New->insertAt(BB, Old.getIterator()); // Insert inst
     Worklist.add(New);
     return New;
   }
diff --git a/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp b/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
--- a/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
@@ -2213,7 +2213,7 @@
         if (Instruction *I = visitBitCast(*BCI)) {
           if (I != BCI) {
             I->takeName(BCI);
-            BCI->getParent()->getInstList().insert(BCI->getIterator(), I);
+            I->insertAt(BCI->getParent(), BCI->getIterator());
             replaceInstUsesWith(*BCI, I);
           }
           return &GEP;
@@ -2419,8 +2419,7 @@
       NewGEP->setOperand(DI, NewPN);
     }
 
-    GEP.getParent()->getInstList().insert(
-        GEP.getParent()->getFirstInsertionPt(), NewGEP);
+    NewGEP->insertAt(GEP.getParent(), GEP.getParent()->getFirstInsertionPt());
     replaceOperand(GEP, 0, NewGEP);
     PtrOp = NewGEP;
   }
@@ -4333,7 +4332,7 @@
             InsertPos = InstParent->getFirstNonPHI()->getIterator();
         }
 
-        InstParent->getInstList().insert(InsertPos, Result);
+        Result->insertAt(InstParent, InsertPos);
 
         // Push the new instruction and any users onto the worklist.
         Worklist.pushUsersToWorkList(*Result);
diff --git a/llvm/lib/Transforms/Instrumentation/ControlHeightReduction.cpp b/llvm/lib/Transforms/Instrumentation/ControlHeightReduction.cpp
--- a/llvm/lib/Transforms/Instrumentation/ControlHeightReduction.cpp
+++ b/llvm/lib/Transforms/Instrumentation/ControlHeightReduction.cpp
@@ -1838,7 +1838,7 @@
   BranchInst *NewBR = BranchInst::Create(NewEntryBlock,
                                          cast<BasicBlock>(VMap[NewEntryBlock]),
                                          ConstantInt::getTrue(F.getContext()));
-  PreEntryBlock->getInstList().push_back(NewBR);
+  NewBR->insertAt(PreEntryBlock, PreEntryBlock->end());
   assert(NewEntryBlock->getSinglePredecessor() == EntryBlock &&
          "NewEntryBlock's only pred must be EntryBlock");
   return NewBR;
diff --git a/llvm/lib/Transforms/Instrumentation/PGOMemOPSizeOpt.cpp b/llvm/lib/Transforms/Instrumentation/PGOMemOPSizeOpt.cpp
--- a/llvm/lib/Transforms/Instrumentation/PGOMemOPSizeOpt.cpp
+++ b/llvm/lib/Transforms/Instrumentation/PGOMemOPSizeOpt.cpp
@@ -422,7 +422,7 @@
     assert(SizeType && "Expected integer type size argument.");
     ConstantInt *CaseSizeId = ConstantInt::get(SizeType, SizeId);
     NewMO.setLength(CaseSizeId);
-    CaseBB->getInstList().push_back(NewMO.I);
+    NewMO.I->insertAt(CaseBB, CaseBB->end());
     IRBuilder<> IRBCase(CaseBB);
     IRBCase.CreateBr(MergeBB);
     SI->addCase(CaseSizeId, CaseBB);
diff --git a/llvm/lib/Transforms/Scalar/JumpThreading.cpp b/llvm/lib/Transforms/Scalar/JumpThreading.cpp
--- a/llvm/lib/Transforms/Scalar/JumpThreading.cpp
+++ b/llvm/lib/Transforms/Scalar/JumpThreading.cpp
@@ -2108,7 +2108,7 @@
   for (; BI != BE; ++BI) {
     Instruction *New = BI->clone();
     New->setName(BI->getName());
-    NewBB->getInstList().push_back(New);
+    New->insertAt(NewBB, NewBB->end());
     ValueMapping[&*BI] = New;
     adaptNoAliasScopes(New, ClonedScopes, Context);
 
@@ -2701,7 +2701,7 @@
     if (New) {
       // Otherwise, insert the new instruction into the block.
       New->setName(BI->getName());
-      PredBB->getInstList().insert(OldPredBranch->getIterator(), New);
+      New->insertAt(PredBB, OldPredBranch->getIterator());
       // Update Dominance from simplified New instruction operands.
       for (unsigned i = 0, e = New->getNumOperands(); i != e; ++i)
         if (BasicBlock *SuccBB = dyn_cast<BasicBlock>(New->getOperand(i)))
@@ -2755,7 +2755,7 @@
                                          BB->getParent(), BB);
   // Move the unconditional branch to NewBB.
   PredTerm->removeFromParent();
-  NewBB->getInstList().insert(NewBB->end(), PredTerm);
+  PredTerm->insertAt(NewBB, NewBB->end());
   // Create a conditional branch and update PHI nodes.
   auto *BI = BranchInst::Create(NewBB, BB, SI->getCondition(), Pred);
   BI->applyMergedLocation(PredTerm->getDebugLoc(), SI->getDebugLoc());
diff --git a/llvm/lib/Transforms/Scalar/LICM.cpp b/llvm/lib/Transforms/Scalar/LICM.cpp
--- a/llvm/lib/Transforms/Scalar/LICM.cpp
+++ b/llvm/lib/Transforms/Scalar/LICM.cpp
@@ -1430,7 +1430,7 @@
     New = I.clone();
   }
 
-  ExitBlock.getInstList().insert(ExitBlock.getFirstInsertionPt(), New);
+  New->insertAt(&ExitBlock, ExitBlock.getFirstInsertionPt());
   if (!I.getName().empty())
     New->setName(I.getName() + ".le");
 
diff --git a/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp b/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp
--- a/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp
@@ -2535,7 +2535,7 @@
         ICmpInst *OldCond = Cond;
         Cond = cast<ICmpInst>(Cond->clone());
         Cond->setName(L->getHeader()->getName() + ".termcond");
-        ExitingBlock->getInstList().insert(TermBr->getIterator(), Cond);
+        Cond->insertAt(ExitingBlock, TermBr->getIterator());
 
         // Clone the IVUse, as the old use still exists!
         CondUse = &IU.AddUser(Cond, CondUse->getOperandValToReplace());
diff --git a/llvm/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp b/llvm/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp
--- a/llvm/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp
+++ b/llvm/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp
@@ -254,7 +254,7 @@
   for (auto *Val : reverse(ToDuplicate)) {
     Instruction *Inst = cast<Instruction>(Val);
     Instruction *NewInst = Inst->clone();
-    BB.getInstList().insert(BB.end(), NewInst);
+    NewInst->insertAt(&BB, BB.end());
     RemapInstruction(NewInst, VMap,
                      RF_NoModuleLevelChanges | RF_IgnoreMissingLocals);
     VMap[Val] = NewInst;
@@ -584,7 +584,7 @@
     if (MSSAU) {
       // Temporarily clone the terminator, to make MSSA update cheaper by
       // separating "insert edge" updates from "remove edge" ones.
-      ParentBB->getInstList().push_back(BI.clone());
+      BI.clone()->insertAt(ParentBB, ParentBB->end());
     } else {
       // Create a new unconditional branch that will continue the loop as a new
       // terminator.
@@ -2254,7 +2254,7 @@
 
     // Keep a clone of the terminator for MSSA updates.
     Instruction *NewTI = TI.clone();
-    ParentBB->getInstList().push_back(NewTI);
+    NewTI->insertAt(ParentBB, ParentBB->end());
 
     // First wire up the moved terminator to the preheaders.
     if (BI) {
diff --git a/llvm/lib/Transforms/Scalar/SimplifyCFGPass.cpp b/llvm/lib/Transforms/Scalar/SimplifyCFGPass.cpp
--- a/llvm/lib/Transforms/Scalar/SimplifyCFGPass.cpp
+++ b/llvm/lib/Transforms/Scalar/SimplifyCFGPass.cpp
@@ -108,12 +108,12 @@
       std::get<1>(I) = PHINode::Create(std::get<0>(I)->getType(),
                                        /*NumReservedValues=*/BBs.size(),
                                        CanonicalBB->getName() + ".op");
-      CanonicalBB->getInstList().push_back(std::get<1>(I));
+      std::get<1>(I)->insertAt(CanonicalBB, CanonicalBB->end());
     }
     // Make it so that this canonical block actually has the right
     // terminator.
     CanonicalTerm = Term->clone();
-    CanonicalBB->getInstList().push_back(CanonicalTerm);
+    CanonicalTerm->insertAt(CanonicalBB, CanonicalBB->end());
     // If the canonical terminator has operands, rewrite it to take PHI's.
     for (auto I : zip(NewOps, CanonicalTerm->operands()))
       std::get<1>(I) = std::get<0>(I);
diff --git a/llvm/lib/Transforms/Scalar/TLSVariableHoist.cpp b/llvm/lib/Transforms/Scalar/TLSVariableHoist.cpp
--- a/llvm/lib/Transforms/Scalar/TLSVariableHoist.cpp
+++ b/llvm/lib/Transforms/Scalar/TLSVariableHoist.cpp
@@ -234,7 +234,7 @@
   BasicBlock::iterator Iter = findInsertPos(Fn, GV, PosBB);
   Type *Ty = GV->getType();
   auto *CastInst = new BitCastInst(GV, Ty, "tls_bitcast");
-  PosBB->getInstList().insert(Iter, CastInst);
+  CastInst->insertAt(PosBB, Iter);
   return CastInst;
 }
 
diff --git a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
--- a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
+++ b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
@@ -555,8 +555,8 @@
   BI = BIL.erase(BI);
 }
 
-void llvm::ReplaceInstWithInst(BasicBlock::InstListType &BIL,
-                               BasicBlock::iterator &BI, Instruction *I) {
+void llvm::ReplaceInstWithInst(BasicBlock *BB, BasicBlock::iterator &BI,
+                               Instruction *I) {
   assert(I->getParent() == nullptr &&
          "ReplaceInstWithInst: Instruction already inserted into basic block!");
 
@@ -566,10 +566,10 @@
     I->setDebugLoc(BI->getDebugLoc());
 
   // Insert the new instruction into the basic block...
-  BasicBlock::iterator New = BIL.insert(BI, I);
+  BasicBlock::iterator New = I->insertAt(BB, BI);
 
   // Replace all uses of the old instruction, and delete it.
-  ReplaceInstWithValue(BIL, BI, I);
+  ReplaceInstWithValue(BB->getInstList(), BI, I);
 
   // Move BI back to point to the newly inserted instruction
   BI = New;
@@ -591,7 +591,7 @@
 
 void llvm::ReplaceInstWithInst(Instruction *From, Instruction *To) {
   BasicBlock::iterator BI(From);
-  ReplaceInstWithInst(From->getParent()->getInstList(), BI, To);
+  ReplaceInstWithInst(From->getParent(), BI, To);
 }
 
 BasicBlock *llvm::SplitEdge(BasicBlock *BB, BasicBlock *Succ, DominatorTree *DT,
@@ -1344,12 +1344,12 @@
   LandingPadInst *LPad = OrigBB->getLandingPadInst();
   Instruction *Clone1 = LPad->clone();
   Clone1->setName(Twine("lpad") + Suffix1);
-  NewBB1->getInstList().insert(NewBB1->getFirstInsertionPt(), Clone1);
+  Clone1->insertAt(NewBB1, NewBB1->getFirstInsertionPt());
 
   if (NewBB2) {
     Instruction *Clone2 = LPad->clone();
     Clone2->setName(Twine("lpad") + Suffix2);
-    NewBB2->getInstList().insert(NewBB2->getFirstInsertionPt(), Clone2);
+    Clone2->insertAt(NewBB2, NewBB2->getFirstInsertionPt());
 
     // Create a PHI node for the two cloned landingpad instructions only
     // if the original landingpad instruction has some uses.
@@ -1400,7 +1400,7 @@
   Instruction *UncondBranch = Pred->getTerminator();
   // Clone the return and add it to the end of the predecessor.
   Instruction *NewRet = RI->clone();
-  Pred->getInstList().push_back(NewRet);
+  NewRet->insertAt(Pred, Pred->end());
 
   // If the return instruction returns a value, and if the value was a
   // PHI node in "BB", propagate the right value into the return.
@@ -1412,7 +1412,7 @@
       // return instruction.
       V = BCI->getOperand(0);
       NewBC = BCI->clone();
-      Pred->getInstList().insert(NewRet->getIterator(), NewBC);
+      NewBC->insertAt(Pred, NewRet->getIterator());
       Op = NewBC;
     }
 
@@ -1422,9 +1422,9 @@
       NewEV = EVI->clone();
       if (NewBC) {
         NewBC->setOperand(0, NewEV);
-        Pred->getInstList().insert(NewBC->getIterator(), NewEV);
+        NewEV->insertAt(Pred, NewBC->getIterator());
       } else {
-        Pred->getInstList().insert(NewRet->getIterator(), NewEV);
+        NewEV->insertAt(Pred, NewRet->getIterator());
         Op = NewEV;
       }
     }
diff --git a/llvm/lib/Transforms/Utils/CloneFunction.cpp b/llvm/lib/Transforms/Utils/CloneFunction.cpp
--- a/llvm/lib/Transforms/Utils/CloneFunction.cpp
+++ b/llvm/lib/Transforms/Utils/CloneFunction.cpp
@@ -58,7 +58,7 @@
     Instruction *NewInst = I.clone();
     if (I.hasName())
       NewInst->setName(I.getName() + NameSuffix);
-    NewBB->getInstList().push_back(NewInst);
+    NewInst->insertAt(NewBB, NewBB->end());
     VMap[&I] = NewInst; // Add instruction map to value.
 
     if (isa<CallInst>(I) && !I.isDebugOrPseudoInst()) {
@@ -521,7 +521,7 @@
     if (II->hasName())
       NewInst->setName(II->getName() + NameSuffix);
     VMap[&*II] = NewInst; // Add instruction map to value.
-    NewBB->getInstList().push_back(NewInst);
+    NewInst->insertAt(NewBB, NewBB->end());
     if (isa<CallInst>(II) && !II->isDebugOrPseudoInst()) {
       hasCalls = true;
       hasMemProfMetadata |= II->hasMetadata(LLVMContext::MD_memprof);
@@ -583,7 +583,7 @@
     Instruction *NewInst = OldTI->clone();
     if (OldTI->hasName())
       NewInst->setName(OldTI->getName() + NameSuffix);
-    NewBB->getInstList().push_back(NewInst);
+    NewInst->insertAt(NewBB, NewBB->end());
     VMap[OldTI] = NewInst; // Add instruction map to value.
 
     if (CodeInfo) {
diff --git a/llvm/lib/Transforms/Utils/CodeExtractor.cpp b/llvm/lib/Transforms/Utils/CodeExtractor.cpp
--- a/llvm/lib/Transforms/Utils/CodeExtractor.cpp
+++ b/llvm/lib/Transforms/Utils/CodeExtractor.cpp
@@ -1208,7 +1208,7 @@
         Idx[1] = ConstantInt::get(Type::getInt32Ty(Context), i);
         GetElementPtrInst *GEP = GetElementPtrInst::Create(
             StructArgTy, Struct, Idx, "gep_" + StructValues[i]->getName());
-        codeReplacer->getInstList().push_back(GEP);
+        GEP->insertAt(codeReplacer, codeReplacer->end());
         new StoreInst(StructValues[i], GEP, codeReplacer);
         NumAggregatedInputs++;
       }
@@ -1226,7 +1226,7 @@
     if (auto DL = newFunction->getEntryBlock().getTerminator()->getDebugLoc())
       call->setDebugLoc(DL);
   }
-  codeReplacer->getInstList().push_back(call);
+  call->insertAt(codeReplacer, codeReplacer->end());
 
   // Set swifterror parameter attributes.
   for (unsigned SwiftErrArgNo : SwiftErrorArgs) {
@@ -1246,7 +1246,7 @@
       Idx[1] = ConstantInt::get(Type::getInt32Ty(Context), aggIdx);
       GetElementPtrInst *GEP = GetElementPtrInst::Create(
           StructArgTy, Struct, Idx, "gep_reload_" + outputs[i]->getName());
-      codeReplacer->getInstList().push_back(GEP);
+      GEP->insertAt(codeReplacer, codeReplacer->end());
       Output = GEP;
       ++aggIdx;
     } else {
@@ -1739,7 +1739,7 @@
       });
     });
   }
-  newFuncRoot->getInstList().push_back(BranchI);
+  BranchI->insertAt(newFuncRoot, newFuncRoot->end());
 
   ValueSet SinkingCands, HoistingCands;
   BasicBlock *CommonExit = nullptr;
diff --git a/llvm/lib/Transforms/Utils/LibCallsShrinkWrap.cpp b/llvm/lib/Transforms/Utils/LibCallsShrinkWrap.cpp
--- a/llvm/lib/Transforms/Utils/LibCallsShrinkWrap.cpp
+++ b/llvm/lib/Transforms/Utils/LibCallsShrinkWrap.cpp
@@ -496,7 +496,7 @@
   assert(SuccBB && "The split block should have a single successor");
   SuccBB->setName("cdce.end");
   CI->removeFromParent();
-  CallBB->getInstList().insert(CallBB->getFirstInsertionPt(), CI);
+  CI->insertAt(CallBB, CallBB->getFirstInsertionPt());
   LLVM_DEBUG(dbgs() << "== Basic Block After ==");
   LLVM_DEBUG(dbgs() << *CallBB->getSinglePredecessor() << *CallBB
                     << *CallBB->getSingleSuccessor() << "\n");
diff --git a/llvm/lib/Transforms/Utils/LowerSwitch.cpp b/llvm/lib/Transforms/Utils/LowerSwitch.cpp
--- a/llvm/lib/Transforms/Utils/LowerSwitch.cpp
+++ b/llvm/lib/Transforms/Utils/LowerSwitch.cpp
@@ -301,7 +301,7 @@
                     NewNode, OrigBlock, Default, UnreachableRanges);
 
   F->getBasicBlockList().insert(++OrigBlock->getIterator(), NewNode);
-  NewNode->getInstList().push_back(Comp);
+  Comp->insertAt(NewNode, NewNode->end());
 
   BranchInst::Create(LBranch, RBranch, Comp, NewNode);
   return NewNode;
diff --git a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp b/llvm/lib/Transforms/Utils/SimplifyCFG.cpp
--- a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp
+++ b/llvm/lib/Transforms/Utils/SimplifyCFG.cpp
@@ -1129,7 +1129,7 @@
     NewBonusInst->dropUndefImplyingAttrsAndUnknownMetadata(
         LLVMContext::MD_annotation);
 
-    PredBlock->getInstList().insert(PTI->getIterator(), NewBonusInst);
+    NewBonusInst->insertAt(PredBlock, PTI->getIterator());
     NewBonusInst->takeName(&BonusInst);
     BonusInst.setName(NewBonusInst->getName() + ".old");
 
@@ -1694,7 +1694,7 @@
 
   // Okay, it is safe to hoist the terminator.
   Instruction *NT = I1->clone();
-  BIParent->getInstList().insert(BI->getIterator(), NT);
+  NT->insertAt(BIParent, BI->getIterator());
   if (!NT->getType()->isVoidTy()) {
     I1->replaceAllUsesWith(NT);
     I2->replaceAllUsesWith(NT);
@@ -2498,7 +2498,7 @@
 
     auto *MergedInvoke = cast<InvokeInst>(II0->clone());
     // NOTE: all invokes have the same attributes, so no handling needed.
-    MergedInvokeBB->getInstList().push_back(MergedInvoke);
+    MergedInvoke->insertAt(MergedInvokeBB, MergedInvokeBB->end());
 
     if (!HasNormalDest) {
       // This set does not have a normal destination,
@@ -3245,7 +3245,7 @@
       }
       if (N) {
         // Insert the new instruction into its new home.
-        EdgeBB->getInstList().insert(InsertPt, N);
+        N->insertAt(EdgeBB, InsertPt);
 
         // Register the new instruction with the assumption cache if necessary.
         if (auto *Assume = dyn_cast<AssumeInst>(N))
diff --git a/llvm/lib/Transforms/Utils/UnifyFunctionExitNodes.cpp b/llvm/lib/Transforms/Utils/UnifyFunctionExitNodes.cpp
--- a/llvm/lib/Transforms/Utils/UnifyFunctionExitNodes.cpp
+++ b/llvm/lib/Transforms/Utils/UnifyFunctionExitNodes.cpp
@@ -90,7 +90,7 @@
     // If the function doesn't return void... add a PHI node to the block...
     PN = PHINode::Create(F.getReturnType(), ReturningBlocks.size(),
                          "UnifiedRetVal");
-    NewRetBlock->getInstList().push_back(PN);
+    PN->insertAt(NewRetBlock, NewRetBlock->end());
     ReturnInst::Create(F.getContext(), PN, NewRetBlock);
   }
 
diff --git a/llvm/unittests/Analysis/AssumeBundleQueriesTest.cpp b/llvm/unittests/Analysis/AssumeBundleQueriesTest.cpp
--- a/llvm/unittests/Analysis/AssumeBundleQueriesTest.cpp
+++ b/llvm/unittests/Analysis/AssumeBundleQueriesTest.cpp
@@ -429,7 +429,7 @@
   BasicBlock *BB = BasicBlock::Create(C);
   BB->insertInto(F);
   Instruction *Ret = ReturnInst::Create(C);
-  BB->getInstList().insert(BB->begin(), Ret);
+  Ret->insertAt(BB, BB->begin());
   Function *FnAssume = Intrinsic::getDeclaration(Mod.get(), Intrinsic::assume);
 
   std::vector<Argument *> ShuffledArgs;
diff --git a/llvm/unittests/Analysis/MemorySSATest.cpp b/llvm/unittests/Analysis/MemorySSATest.cpp
--- a/llvm/unittests/Analysis/MemorySSATest.cpp
+++ b/llvm/unittests/Analysis/MemorySSATest.cpp
@@ -282,7 +282,7 @@
   // - remove from original block
 
   LoadInst *LoadInstClone = cast<LoadInst>(LoadInst1->clone());
-  Merge->getInstList().insert(Merge->begin(), LoadInstClone);
+  LoadInstClone->insertAt(Merge, Merge->begin());
   MemoryAccess * NewLoadAccess =
       Updater.createMemoryAccessInBB(LoadInstClone, nullptr,
                                      LoadInstClone->getParent(),
diff --git a/llvm/unittests/Analysis/ValueTrackingTest.cpp b/llvm/unittests/Analysis/ValueTrackingTest.cpp
--- a/llvm/unittests/Analysis/ValueTrackingTest.cpp
+++ b/llvm/unittests/Analysis/ValueTrackingTest.cpp
@@ -1624,7 +1624,7 @@
   EXPECT_EQ(Known.Zero.getZExtValue(), 0u);
 
   BasicBlock *BB = BasicBlock::Create(Context);
-  BB->getInstList().push_back(CI);
+  CI->insertAt(BB, BB->end());
   Known = computeKnownBits(CI, M.getDataLayout(), /* Depth */ 0);
   // There is no parent function so we cannot look up the vscale_range
   // attribute to determine the number of bits.