YQ Connector: support managed ClickHouse

Со стороны dqrun можно обратиться к инстансу коннектора, который работает на streaming стенде, и извлечь данные из облачного CH.

1 files changed, 619 insertions, 0 deletions

diff --git a/contrib/libs/llvm14/lib/CodeGen/StackProtector.cpp b/contrib/libs/llvm14/lib/CodeGen/StackProtector.cpp
new file mode 100644
index 0000000000..6765fd2746
--- /dev/null
+++ b/contrib/libs/llvm14/lib/CodeGen/StackProtector.cpp
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+//===- 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/EHPersonalities.h"
+#include "llvm/Analysis/MemoryLocation.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/InitializePasses.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;
+
+StackProtector::StackProtector() : FunctionPass(ID), SSPBufferSize(8) {
+  initializeStackProtectorPass(*PassRegistry::getPassRegistry());
+}
+
+INITIALIZE_PASS_BEGIN(StackProtector, DEBUG_TYPE,
+                      "Insert stack protectors", false, true)
+INITIALIZE_PASS_DEPENDENCY(TargetPassConfig)
+INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass)
+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 (Type *ET : ST->elements())
+    if (ContainsProtectableArray(ET, 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;
+}
+
+bool StackProtector::HasAddressTaken(const Instruction *AI,
+                                     TypeSize AllocSize) {
+  const DataLayout &DL = M->getDataLayout();
+  for (const User *U : AI->users()) {
+    const auto *I = cast<Instruction>(U);
+    // If this instruction accesses memory make sure it doesn't access beyond
+    // the bounds of the allocated object.
+    Optional<MemoryLocation> MemLoc = MemoryLocation::getOrNone(I);
+    if (MemLoc.hasValue() && MemLoc->Size.hasValue() &&
+        !TypeSize::isKnownGE(AllocSize,
+                             TypeSize::getFixed(MemLoc->Size.getValue())))
+      return true;
+    switch (I->getOpcode()) {
+    case Instruction::Store:
+      if (AI == cast<StoreInst>(I)->getValueOperand())
+        return true;
+      break;
+    case Instruction::AtomicCmpXchg:
+      // cmpxchg conceptually includes both a load and store from the same
+      // location. So, like store, the value being stored is what matters.
+      if (AI == cast<AtomicCmpXchgInst>(I)->getNewValOperand())
+        return true;
+      break;
+    case Instruction::PtrToInt:
+      if (AI == cast<PtrToIntInst>(I)->getOperand(0))
+        return true;
+      break;
+    case Instruction::Call: {
+      // Ignore intrinsics that do not become real instructions.
+      // TODO: Narrow this to intrinsics that have store-like effects.
+      const auto *CI = cast<CallInst>(I);
+      if (!CI->isDebugOrPseudoInst() && !CI->isLifetimeStartOrEnd())
+        return true;
+      break;
+    }
+    case Instruction::Invoke:
+      return true;
+    case Instruction::GetElementPtr: {
+      // If the GEP offset is out-of-bounds, or is non-constant and so has to be
+      // assumed to be potentially out-of-bounds, then any memory access that
+      // would use it could also be out-of-bounds meaning stack protection is
+      // required.
+      const GetElementPtrInst *GEP = cast<GetElementPtrInst>(I);
+      unsigned IndexSize = DL.getIndexTypeSizeInBits(I->getType());
+      APInt Offset(IndexSize, 0);
+      if (!GEP->accumulateConstantOffset(DL, Offset))
+        return true;
+      TypeSize OffsetSize = TypeSize::Fixed(Offset.getLimitedValue());
+      if (!TypeSize::isKnownGT(AllocSize, OffsetSize))
+        return true;
+      // Adjust AllocSize to be the space remaining after this offset.
+      // We can't subtract a fixed size from a scalable one, so in that case
+      // assume the scalable value is of minimum size.
+      TypeSize NewAllocSize =
+          TypeSize::Fixed(AllocSize.getKnownMinValue()) - OffsetSize;
+      if (HasAddressTaken(I, NewAllocSize))
+        return true;
+      break;
+    }
+    case Instruction::BitCast:
+    case Instruction::Select:
+    case Instruction::AddrSpaceCast:
+      if (HasAddressTaken(I, AllocSize))
+        return true;
+      break;
+    case Instruction::PHI: {
+      // Keep track of what PHI nodes we have already visited to ensure
+      // they are only visited once.
+      const auto *PN = cast<PHINode>(I);
+      if (VisitedPHIs.insert(PN).second)
+        if (HasAddressTaken(PN, AllocSize))
+          return true;
+      break;
+    }
+    case Instruction::Load:
+    case Instruction::AtomicRMW:
+    case Instruction::Ret:
+      // These instructions take an address operand, but have load-like or
+      // other innocuous behavior that should not trigger a stack protector.
+      // atomicrmw conceptually has both load and store semantics, but the
+      // value being stored must be integer; so if a pointer is being stored,
+      // we'll catch it in the PtrToInt case above.
+      break;
+    default:
+      // Conservatively return true for any instruction that takes an address
+      // operand, but is not handled above.
+      return true;
+    }
+  }
+  return false;
+}
+
+/// 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 auto *II = dyn_cast<IntrinsicInst>(&I))
+        if (II->getIntrinsicID() == Intrinsic::stackprotector)
+          return II;
+  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;
+
+  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 (!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 && HasAddressTaken(AI, M->getDataLayout().getTypeAllocSize(
+                                              AI->getAllocatedType()))) {
+          ++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;
+        }
+        // Clear any PHIs that we visited, to make sure we examine all uses of
+        // any subsequent allocas that we look at.
+        VisitedPHIs.clear();
+      }
+    }
+  }
+
+  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) {
+  Value *Guard = TLI->getIRStackGuard(B);
+  StringRef GuardMode = M->getStackProtectorGuard();
+  if ((GuardMode == "tls" || GuardMode.empty()) && Guard)
+    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);
+  AllocaInst *AI = nullptr; // Place on stack that stores the stack guard.
+
+  for (BasicBlock &BB : llvm::make_early_inc_range(*F)) {
+    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;
+
+    // If we're instrumenting a block with a musttail call, the check has to be
+    // inserted before the call rather than between it and the return. The
+    // verifier guarantees that a musttail call is either directly before the
+    // return or with a single correct bitcast of the return value in between so
+    // we don't need to worry about many situations here.
+    Instruction *CheckLoc = RI;
+    Instruction *Prev = RI->getPrevNonDebugInstruction();
+    if (Prev && isa<CallInst>(Prev) && cast<CallInst>(Prev)->isMustTailCall())
+      CheckLoc = Prev;
+    else if (Prev) {
+      Prev = Prev->getPrevNonDebugInstruction();
+      if (Prev && isa<CallInst>(Prev) && cast<CallInst>(Prev)->isMustTailCall())
+        CheckLoc = Prev;
+    }
+
+    // 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(CheckLoc);
+      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 calls, generate IR level
+      // 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(CheckLoc->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);
+  if (F->getSubprogram())
+    B.SetCurrentDebugLocation(
+        DILocation::get(Context, 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);
+  }
+}