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diff --git a/contrib/llvm/lib/CodeGen/StackProtector.cpp b/contrib/llvm/lib/CodeGen/StackProtector.cpp
deleted file mode 100644
index 809960c7fdf9..000000000000
--- a/contrib/llvm/lib/CodeGen/StackProtector.cpp
+++ /dev/null
@@ -1,507 +0,0 @@
-//===- StackProtector.cpp - Stack Protector Insertion ---------------------===//
-//
-// 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
-//
-//===----------------------------------------------------------------------===//
-//
-// This pass inserts stack protectors into functions which need them. A variable
-// with a random value in it is stored onto the stack before the local variables
-// are allocated. Upon exiting the block, the stored value is checked. If it's
-// changed, then there was some sort of violation and the program aborts.
-//
-//===----------------------------------------------------------------------===//
-
-#include "llvm/CodeGen/StackProtector.h"
-#include "llvm/ADT/SmallPtrSet.h"
-#include "llvm/ADT/Statistic.h"
-#include "llvm/Analysis/BranchProbabilityInfo.h"
-#include "llvm/Analysis/CaptureTracking.h"
-#include "llvm/Analysis/EHPersonalities.h"
-#include "llvm/Analysis/OptimizationRemarkEmitter.h"
-#include "llvm/CodeGen/Passes.h"
-#include "llvm/CodeGen/TargetLowering.h"
-#include "llvm/CodeGen/TargetPassConfig.h"
-#include "llvm/CodeGen/TargetSubtargetInfo.h"
-#include "llvm/IR/Attributes.h"
-#include "llvm/IR/BasicBlock.h"
-#include "llvm/IR/Constants.h"
-#include "llvm/IR/DataLayout.h"
-#include "llvm/IR/DebugInfo.h"
-#include "llvm/IR/DebugLoc.h"
-#include "llvm/IR/DerivedTypes.h"
-#include "llvm/IR/Dominators.h"
-#include "llvm/IR/Function.h"
-#include "llvm/IR/IRBuilder.h"
-#include "llvm/IR/Instruction.h"
-#include "llvm/IR/Instructions.h"
-#include "llvm/IR/IntrinsicInst.h"
-#include "llvm/IR/Intrinsics.h"
-#include "llvm/IR/MDBuilder.h"
-#include "llvm/IR/Module.h"
-#include "llvm/IR/Type.h"
-#include "llvm/IR/User.h"
-#include "llvm/Pass.h"
-#include "llvm/Support/Casting.h"
-#include "llvm/Support/CommandLine.h"
-#include "llvm/Target/TargetMachine.h"
-#include "llvm/Target/TargetOptions.h"
-#include <utility>
-
-using namespace llvm;
-
-#define DEBUG_TYPE "stack-protector"
-
-STATISTIC(NumFunProtected, "Number of functions protected");
-STATISTIC(NumAddrTaken, "Number of local variables that have their address"
-                        " taken.");
-
-static cl::opt<bool> EnableSelectionDAGSP("enable-selectiondag-sp",
-                                          cl::init(true), cl::Hidden);
-
-char StackProtector::ID = 0;
-
-INITIALIZE_PASS_BEGIN(StackProtector, DEBUG_TYPE,
-                      "Insert stack protectors", false, true)
-INITIALIZE_PASS_DEPENDENCY(TargetPassConfig)
-INITIALIZE_PASS_END(StackProtector, DEBUG_TYPE,
-                    "Insert stack protectors", false, true)
-
-FunctionPass *llvm::createStackProtectorPass() { return new StackProtector(); }
-
-void StackProtector::getAnalysisUsage(AnalysisUsage &AU) const {
-  AU.addRequired<TargetPassConfig>();
-  AU.addPreserved<DominatorTreeWrapperPass>();
-}
-
-bool StackProtector::runOnFunction(Function &Fn) {
-  F = &Fn;
-  M = F->getParent();
-  DominatorTreeWrapperPass *DTWP =
-      getAnalysisIfAvailable<DominatorTreeWrapperPass>();
-  DT = DTWP ? &DTWP->getDomTree() : nullptr;
-  TM = &getAnalysis<TargetPassConfig>().getTM<TargetMachine>();
-  Trip = TM->getTargetTriple();
-  TLI = TM->getSubtargetImpl(Fn)->getTargetLowering();
-  HasPrologue = false;
-  HasIRCheck = false;
-
-  Attribute Attr = Fn.getFnAttribute("stack-protector-buffer-size");
-  if (Attr.isStringAttribute() &&
-      Attr.getValueAsString().getAsInteger(10, SSPBufferSize))
-    return false; // Invalid integer string
-
-  if (!RequiresStackProtector())
-    return false;
-
-  // TODO(etienneb): Functions with funclets are not correctly supported now.
-  // Do nothing if this is funclet-based personality.
-  if (Fn.hasPersonalityFn()) {
-    EHPersonality Personality = classifyEHPersonality(Fn.getPersonalityFn());
-    if (isFuncletEHPersonality(Personality))
-      return false;
-  }
-
-  ++NumFunProtected;
-  return InsertStackProtectors();
-}
-
-/// \param [out] IsLarge is set to true if a protectable array is found and
-/// it is "large" ( >= ssp-buffer-size).  In the case of a structure with
-/// multiple arrays, this gets set if any of them is large.
-bool StackProtector::ContainsProtectableArray(Type *Ty, bool &IsLarge,
-                                              bool Strong,
-                                              bool InStruct) const {
-  if (!Ty)
-    return false;
-  if (ArrayType *AT = dyn_cast<ArrayType>(Ty)) {
-    if (!AT->getElementType()->isIntegerTy(8)) {
-      // If we're on a non-Darwin platform or we're inside of a structure, don't
-      // add stack protectors unless the array is a character array.
-      // However, in strong mode any array, regardless of type and size,
-      // triggers a protector.
-      if (!Strong && (InStruct || !Trip.isOSDarwin()))
-        return false;
-    }
-
-    // If an array has more than SSPBufferSize bytes of allocated space, then we
-    // emit stack protectors.
-    if (SSPBufferSize <= M->getDataLayout().getTypeAllocSize(AT)) {
-      IsLarge = true;
-      return true;
-    }
-
-    if (Strong)
-      // Require a protector for all arrays in strong mode
-      return true;
-  }
-
-  const StructType *ST = dyn_cast<StructType>(Ty);
-  if (!ST)
-    return false;
-
-  bool NeedsProtector = false;
-  for (StructType::element_iterator I = ST->element_begin(),
-                                    E = ST->element_end();
-       I != E; ++I)
-    if (ContainsProtectableArray(*I, IsLarge, Strong, true)) {
-      // If the element is a protectable array and is large (>= SSPBufferSize)
-      // then we are done.  If the protectable array is not large, then
-      // keep looking in case a subsequent element is a large array.
-      if (IsLarge)
-        return true;
-      NeedsProtector = true;
-    }
-
-  return NeedsProtector;
-}
-
-/// Search for the first call to the llvm.stackprotector intrinsic and return it
-/// if present.
-static const CallInst *findStackProtectorIntrinsic(Function &F) {
-  for (const BasicBlock &BB : F)
-    for (const Instruction &I : BB)
-      if (const CallInst *CI = dyn_cast<CallInst>(&I))
-        if (CI->getCalledFunction() ==
-            Intrinsic::getDeclaration(F.getParent(), Intrinsic::stackprotector))
-          return CI;
-  return nullptr;
-}
-
-/// Check whether or not this function needs a stack protector based
-/// upon the stack protector level.
-///
-/// We use two heuristics: a standard (ssp) and strong (sspstrong).
-/// The standard heuristic which will add a guard variable to functions that
-/// call alloca with a either a variable size or a size >= SSPBufferSize,
-/// functions with character buffers larger than SSPBufferSize, and functions
-/// with aggregates containing character buffers larger than SSPBufferSize. The
-/// strong heuristic will add a guard variables to functions that call alloca
-/// regardless of size, functions with any buffer regardless of type and size,
-/// functions with aggregates that contain any buffer regardless of type and
-/// size, and functions that contain stack-based variables that have had their
-/// address taken.
-bool StackProtector::RequiresStackProtector() {
-  bool Strong = false;
-  bool NeedsProtector = false;
-  HasPrologue = findStackProtectorIntrinsic(*F);
-
-  if (F->hasFnAttribute(Attribute::SafeStack))
-    return false;
-
-  // We are constructing the OptimizationRemarkEmitter on the fly rather than
-  // using the analysis pass to avoid building DominatorTree and LoopInfo which
-  // are not available this late in the IR pipeline.
-  OptimizationRemarkEmitter ORE(F);
-
-  if (F->hasFnAttribute(Attribute::StackProtectReq)) {
-    ORE.emit([&]() {
-      return OptimizationRemark(DEBUG_TYPE, "StackProtectorRequested", F)
-             << "Stack protection applied to function "
-             << ore::NV("Function", F)
-             << " due to a function attribute or command-line switch";
-    });
-    NeedsProtector = true;
-    Strong = true; // Use the same heuristic as strong to determine SSPLayout
-  } else if (F->hasFnAttribute(Attribute::StackProtectStrong))
-    Strong = true;
-  else if (HasPrologue)
-    NeedsProtector = true;
-  else if (!F->hasFnAttribute(Attribute::StackProtect))
-    return false;
-
-  for (const BasicBlock &BB : *F) {
-    for (const Instruction &I : BB) {
-      if (const AllocaInst *AI = dyn_cast<AllocaInst>(&I)) {
-        if (AI->isArrayAllocation()) {
-          auto RemarkBuilder = [&]() {
-            return OptimizationRemark(DEBUG_TYPE, "StackProtectorAllocaOrArray",
-                                      &I)
-                   << "Stack protection applied to function "
-                   << ore::NV("Function", F)
-                   << " due to a call to alloca or use of a variable length "
-                      "array";
-          };
-          if (const auto *CI = dyn_cast<ConstantInt>(AI->getArraySize())) {
-            if (CI->getLimitedValue(SSPBufferSize) >= SSPBufferSize) {
-              // A call to alloca with size >= SSPBufferSize requires
-              // stack protectors.
-              Layout.insert(std::make_pair(AI,
-                                           MachineFrameInfo::SSPLK_LargeArray));
-              ORE.emit(RemarkBuilder);
-              NeedsProtector = true;
-            } else if (Strong) {
-              // Require protectors for all alloca calls in strong mode.
-              Layout.insert(std::make_pair(AI,
-                                           MachineFrameInfo::SSPLK_SmallArray));
-              ORE.emit(RemarkBuilder);
-              NeedsProtector = true;
-            }
-          } else {
-            // A call to alloca with a variable size requires protectors.
-            Layout.insert(std::make_pair(AI,
-                                         MachineFrameInfo::SSPLK_LargeArray));
-            ORE.emit(RemarkBuilder);
-            NeedsProtector = true;
-          }
-          continue;
-        }
-
-        bool IsLarge = false;
-        if (ContainsProtectableArray(AI->getAllocatedType(), IsLarge, Strong)) {
-          Layout.insert(std::make_pair(AI, IsLarge
-                                       ? MachineFrameInfo::SSPLK_LargeArray
-                                       : MachineFrameInfo::SSPLK_SmallArray));
-          ORE.emit([&]() {
-            return OptimizationRemark(DEBUG_TYPE, "StackProtectorBuffer", &I)
-                   << "Stack protection applied to function "
-                   << ore::NV("Function", F)
-                   << " due to a stack allocated buffer or struct containing a "
-                      "buffer";
-          });
-          NeedsProtector = true;
-          continue;
-        }
-
-        if (Strong && PointerMayBeCaptured(AI,
-                                           /* ReturnCaptures */ false,
-                                           /* StoreCaptures */ true)) {
-          ++NumAddrTaken;
-          Layout.insert(std::make_pair(AI, MachineFrameInfo::SSPLK_AddrOf));
-          ORE.emit([&]() {
-            return OptimizationRemark(DEBUG_TYPE, "StackProtectorAddressTaken",
-                                      &I)
-                   << "Stack protection applied to function "
-                   << ore::NV("Function", F)
-                   << " due to the address of a local variable being taken";
-          });
-          NeedsProtector = true;
-        }
-      }
-    }
-  }
-
-  return NeedsProtector;
-}
-
-/// Create a stack guard loading and populate whether SelectionDAG SSP is
-/// supported.
-static Value *getStackGuard(const TargetLoweringBase *TLI, Module *M,
-                            IRBuilder<> &B,
-                            bool *SupportsSelectionDAGSP = nullptr) {
-  if (Value *Guard = TLI->getIRStackGuard(B))
-    return B.CreateLoad(B.getInt8PtrTy(), Guard, true, "StackGuard");
-
-  // Use SelectionDAG SSP handling, since there isn't an IR guard.
-  //
-  // This is more or less weird, since we optionally output whether we
-  // should perform a SelectionDAG SP here. The reason is that it's strictly
-  // defined as !TLI->getIRStackGuard(B), where getIRStackGuard is also
-  // mutating. There is no way to get this bit without mutating the IR, so
-  // getting this bit has to happen in this right time.
-  //
-  // We could have define a new function TLI::supportsSelectionDAGSP(), but that
-  // will put more burden on the backends' overriding work, especially when it
-  // actually conveys the same information getIRStackGuard() already gives.
-  if (SupportsSelectionDAGSP)
-    *SupportsSelectionDAGSP = true;
-  TLI->insertSSPDeclarations(*M);
-  return B.CreateCall(Intrinsic::getDeclaration(M, Intrinsic::stackguard));
-}
-
-/// Insert code into the entry block that stores the stack guard
-/// variable onto the stack:
-///
-///   entry:
-///     StackGuardSlot = alloca i8*
-///     StackGuard = <stack guard>
-///     call void @llvm.stackprotector(StackGuard, StackGuardSlot)
-///
-/// Returns true if the platform/triple supports the stackprotectorcreate pseudo
-/// node.
-static bool CreatePrologue(Function *F, Module *M, ReturnInst *RI,
-                           const TargetLoweringBase *TLI, AllocaInst *&AI) {
-  bool SupportsSelectionDAGSP = false;
-  IRBuilder<> B(&F->getEntryBlock().front());
-  PointerType *PtrTy = Type::getInt8PtrTy(RI->getContext());
-  AI = B.CreateAlloca(PtrTy, nullptr, "StackGuardSlot");
-
-  Value *GuardSlot = getStackGuard(TLI, M, B, &SupportsSelectionDAGSP);
-  B.CreateCall(Intrinsic::getDeclaration(M, Intrinsic::stackprotector),
-               {GuardSlot, AI});
-  return SupportsSelectionDAGSP;
-}
-
-/// InsertStackProtectors - Insert code into the prologue and epilogue of the
-/// function.
-///
-///  - The prologue code loads and stores the stack guard onto the stack.
-///  - The epilogue checks the value stored in the prologue against the original
-///    value. It calls __stack_chk_fail if they differ.
-bool StackProtector::InsertStackProtectors() {
-  // If the target wants to XOR the frame pointer into the guard value, it's
-  // impossible to emit the check in IR, so the target *must* support stack
-  // protection in SDAG.
-  bool SupportsSelectionDAGSP =
-      TLI->useStackGuardXorFP() ||
-      (EnableSelectionDAGSP && !TM->Options.EnableFastISel &&
-       !TM->Options.EnableGlobalISel);
-  AllocaInst *AI = nullptr;       // Place on stack that stores the stack guard.
-
-  for (Function::iterator I = F->begin(), E = F->end(); I != E;) {
-    BasicBlock *BB = &*I++;
-    ReturnInst *RI = dyn_cast<ReturnInst>(BB->getTerminator());
-    if (!RI)
-      continue;
-
-    // Generate prologue instrumentation if not already generated.
-    if (!HasPrologue) {
-      HasPrologue = true;
-      SupportsSelectionDAGSP &= CreatePrologue(F, M, RI, TLI, AI);
-    }
-
-    // SelectionDAG based code generation. Nothing else needs to be done here.
-    // The epilogue instrumentation is postponed to SelectionDAG.
-    if (SupportsSelectionDAGSP)
-      break;
-
-    // Find the stack guard slot if the prologue was not created by this pass
-    // itself via a previous call to CreatePrologue().
-    if (!AI) {
-      const CallInst *SPCall = findStackProtectorIntrinsic(*F);
-      assert(SPCall && "Call to llvm.stackprotector is missing");
-      AI = cast<AllocaInst>(SPCall->getArgOperand(1));
-    }
-
-    // Set HasIRCheck to true, so that SelectionDAG will not generate its own
-    // version. SelectionDAG called 'shouldEmitSDCheck' to check whether
-    // instrumentation has already been generated.
-    HasIRCheck = true;
-
-    // Generate epilogue instrumentation. The epilogue intrumentation can be
-    // function-based or inlined depending on which mechanism the target is
-    // providing.
-    if (Function *GuardCheck = TLI->getSSPStackGuardCheck(*M)) {
-      // Generate the function-based epilogue instrumentation.
-      // The target provides a guard check function, generate a call to it.
-      IRBuilder<> B(RI);
-      LoadInst *Guard = B.CreateLoad(B.getInt8PtrTy(), AI, true, "Guard");
-      CallInst *Call = B.CreateCall(GuardCheck, {Guard});
-      Call->setAttributes(GuardCheck->getAttributes());
-      Call->setCallingConv(GuardCheck->getCallingConv());
-    } else {
-      // Generate the epilogue with inline instrumentation.
-      // If we do not support SelectionDAG based tail calls, generate IR level
-      // tail calls.
-      //
-      // For each block with a return instruction, convert this:
-      //
-      //   return:
-      //     ...
-      //     ret ...
-      //
-      // into this:
-      //
-      //   return:
-      //     ...
-      //     %1 = <stack guard>
-      //     %2 = load StackGuardSlot
-      //     %3 = cmp i1 %1, %2
-      //     br i1 %3, label %SP_return, label %CallStackCheckFailBlk
-      //
-      //   SP_return:
-      //     ret ...
-      //
-      //   CallStackCheckFailBlk:
-      //     call void @__stack_chk_fail()
-      //     unreachable
-
-      // Create the FailBB. We duplicate the BB every time since the MI tail
-      // merge pass will merge together all of the various BB into one including
-      // fail BB generated by the stack protector pseudo instruction.
-      BasicBlock *FailBB = CreateFailBB();
-
-      // Split the basic block before the return instruction.
-      BasicBlock *NewBB = BB->splitBasicBlock(RI->getIterator(), "SP_return");
-
-      // Update the dominator tree if we need to.
-      if (DT && DT->isReachableFromEntry(BB)) {
-        DT->addNewBlock(NewBB, BB);
-        DT->addNewBlock(FailBB, BB);
-      }
-
-      // Remove default branch instruction to the new BB.
-      BB->getTerminator()->eraseFromParent();
-
-      // Move the newly created basic block to the point right after the old
-      // basic block so that it's in the "fall through" position.
-      NewBB->moveAfter(BB);
-
-      // Generate the stack protector instructions in the old basic block.
-      IRBuilder<> B(BB);
-      Value *Guard = getStackGuard(TLI, M, B);
-      LoadInst *LI2 = B.CreateLoad(B.getInt8PtrTy(), AI, true);
-      Value *Cmp = B.CreateICmpEQ(Guard, LI2);
-      auto SuccessProb =
-          BranchProbabilityInfo::getBranchProbStackProtector(true);
-      auto FailureProb =
-          BranchProbabilityInfo::getBranchProbStackProtector(false);
-      MDNode *Weights = MDBuilder(F->getContext())
-                            .createBranchWeights(SuccessProb.getNumerator(),
-                                                 FailureProb.getNumerator());
-      B.CreateCondBr(Cmp, NewBB, FailBB, Weights);
-    }
-  }
-
-  // Return if we didn't modify any basic blocks. i.e., there are no return
-  // statements in the function.
-  return HasPrologue;
-}
-
-/// CreateFailBB - Create a basic block to jump to when the stack protector
-/// check fails.
-BasicBlock *StackProtector::CreateFailBB() {
-  LLVMContext &Context = F->getContext();
-  BasicBlock *FailBB = BasicBlock::Create(Context, "CallStackCheckFailBlk", F);
-  IRBuilder<> B(FailBB);
-  B.SetCurrentDebugLocation(DebugLoc::get(0, 0, F->getSubprogram()));
-  if (Trip.isOSOpenBSD()) {
-    FunctionCallee StackChkFail = M->getOrInsertFunction(
-        "__stack_smash_handler", Type::getVoidTy(Context),
-        Type::getInt8PtrTy(Context));
-
-    B.CreateCall(StackChkFail, B.CreateGlobalStringPtr(F->getName(), "SSH"));
-  } else {
-    FunctionCallee StackChkFail =
-        M->getOrInsertFunction("__stack_chk_fail", Type::getVoidTy(Context));
-
-    B.CreateCall(StackChkFail, {});
-  }
-  B.CreateUnreachable();
-  return FailBB;
-}
-
-bool StackProtector::shouldEmitSDCheck(const BasicBlock &BB) const {
-  return HasPrologue && !HasIRCheck && isa<ReturnInst>(BB.getTerminator());
-}
-
-void StackProtector::copyToMachineFrameInfo(MachineFrameInfo &MFI) const {
-  if (Layout.empty())
-    return;
-
-  for (int I = 0, E = MFI.getObjectIndexEnd(); I != E; ++I) {
-    if (MFI.isDeadObjectIndex(I))
-      continue;
-
-    const AllocaInst *AI = MFI.getObjectAllocation(I);
-    if (!AI)
-      continue;
-
-    SSPLayoutMap::const_iterator LI = Layout.find(AI);
-    if (LI == Layout.end())
-      continue;
-
-    MFI.setObjectSSPLayout(I, LI->second);
-  }
-}