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diff --git a/gnu/llvm/lib/Target/XCore/XCoreLowerThreadLocal.cpp b/gnu/llvm/lib/Target/XCore/XCoreLowerThreadLocal.cpp
new file mode 100644
index 00000000000..f0b720151b1
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+++ b/gnu/llvm/lib/Target/XCore/XCoreLowerThreadLocal.cpp
@@ -0,0 +1,238 @@
+//===-- XCoreLowerThreadLocal - Lower thread local variables --------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// \brief This file contains a pass that lowers thread local variables on the
+///        XCore.
+///
+//===----------------------------------------------------------------------===//
+
+#include "XCore.h"
+#include "llvm/IR/Constants.h"
+#include "llvm/IR/DerivedTypes.h"
+#include "llvm/IR/GlobalVariable.h"
+#include "llvm/IR/IRBuilder.h"
+#include "llvm/IR/Intrinsics.h"
+#include "llvm/IR/Module.h"
+#include "llvm/IR/NoFolder.h"
+#include "llvm/IR/ValueHandle.h"
+#include "llvm/Pass.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Transforms/Utils/BasicBlockUtils.h"
+
+#define DEBUG_TYPE "xcore-lower-thread-local"
+
+using namespace llvm;
+
+static cl::opt<unsigned> MaxThreads(
+  "xcore-max-threads", cl::Optional,
+  cl::desc("Maximum number of threads (for emulation thread-local storage)"),
+  cl::Hidden, cl::value_desc("number"), cl::init(8));
+
+namespace {
+  /// Lowers thread local variables on the XCore. Each thread local variable is
+  /// expanded to an array of n elements indexed by the thread ID where n is the
+  /// fixed number hardware threads supported by the device.
+  struct XCoreLowerThreadLocal : public ModulePass {
+    static char ID;
+
+    XCoreLowerThreadLocal() : ModulePass(ID) {
+      initializeXCoreLowerThreadLocalPass(*PassRegistry::getPassRegistry());
+    }
+
+    bool lowerGlobal(GlobalVariable *GV);
+
+    bool runOnModule(Module &M) override;
+  };
+}
+
+char XCoreLowerThreadLocal::ID = 0;
+
+INITIALIZE_PASS(XCoreLowerThreadLocal, "xcore-lower-thread-local",
+                "Lower thread local variables", false, false)
+
+ModulePass *llvm::createXCoreLowerThreadLocalPass() {
+  return new XCoreLowerThreadLocal();
+}
+
+static ArrayType *createLoweredType(Type *OriginalType) {
+  return ArrayType::get(OriginalType, MaxThreads);
+}
+
+static Constant *
+createLoweredInitializer(ArrayType *NewType, Constant *OriginalInitializer) {
+  SmallVector<Constant *, 8> Elements(MaxThreads);
+  for (unsigned i = 0; i != MaxThreads; ++i) {
+    Elements[i] = OriginalInitializer;
+  }
+  return ConstantArray::get(NewType, Elements);
+}
+
+static Instruction *
+createReplacementInstr(ConstantExpr *CE, Instruction *Instr) {
+  IRBuilder<true,NoFolder> Builder(Instr);
+  unsigned OpCode = CE->getOpcode();
+  switch (OpCode) {
+    case Instruction::GetElementPtr: {
+      SmallVector<Value *,4> CEOpVec(CE->op_begin(), CE->op_end());
+      ArrayRef<Value *> CEOps(CEOpVec);
+      return dyn_cast<Instruction>(Builder.CreateInBoundsGEP(
+          cast<GEPOperator>(CE)->getSourceElementType(), CEOps[0],
+          CEOps.slice(1)));
+    }
+    case Instruction::Add:
+    case Instruction::Sub:
+    case Instruction::Mul:
+    case Instruction::UDiv:
+    case Instruction::SDiv:
+    case Instruction::FDiv:
+    case Instruction::URem:
+    case Instruction::SRem:
+    case Instruction::FRem:
+    case Instruction::Shl:
+    case Instruction::LShr:
+    case Instruction::AShr:
+    case Instruction::And:
+    case Instruction::Or:
+    case Instruction::Xor:
+      return dyn_cast<Instruction>(
+                  Builder.CreateBinOp((Instruction::BinaryOps)OpCode,
+                                      CE->getOperand(0), CE->getOperand(1),
+                                      CE->getName()));
+    case Instruction::Trunc:
+    case Instruction::ZExt:
+    case Instruction::SExt:
+    case Instruction::FPToUI:
+    case Instruction::FPToSI:
+    case Instruction::UIToFP:
+    case Instruction::SIToFP:
+    case Instruction::FPTrunc:
+    case Instruction::FPExt:
+    case Instruction::PtrToInt:
+    case Instruction::IntToPtr:
+    case Instruction::BitCast:
+      return dyn_cast<Instruction>(
+                  Builder.CreateCast((Instruction::CastOps)OpCode,
+                                     CE->getOperand(0), CE->getType(),
+                                     CE->getName()));
+    default:
+      llvm_unreachable("Unhandled constant expression!\n");
+  }
+}
+
+static bool replaceConstantExprOp(ConstantExpr *CE, Pass *P) {
+  do {
+    SmallVector<WeakVH,8> WUsers(CE->user_begin(), CE->user_end());
+    std::sort(WUsers.begin(), WUsers.end());
+    WUsers.erase(std::unique(WUsers.begin(), WUsers.end()), WUsers.end());
+    while (!WUsers.empty())
+      if (WeakVH WU = WUsers.pop_back_val()) {
+        if (PHINode *PN = dyn_cast<PHINode>(WU)) {
+          for (int I = 0, E = PN->getNumIncomingValues(); I < E; ++I)
+            if (PN->getIncomingValue(I) == CE) {
+              BasicBlock *PredBB = PN->getIncomingBlock(I);
+              if (PredBB->getTerminator()->getNumSuccessors() > 1)
+                PredBB = SplitEdge(PredBB, PN->getParent());
+              Instruction *InsertPos = PredBB->getTerminator();
+              Instruction *NewInst = createReplacementInstr(CE, InsertPos);
+              PN->setOperand(I, NewInst);
+            }
+        } else if (Instruction *Instr = dyn_cast<Instruction>(WU)) {
+          Instruction *NewInst = createReplacementInstr(CE, Instr);
+          Instr->replaceUsesOfWith(CE, NewInst);
+        } else {
+          ConstantExpr *CExpr = dyn_cast<ConstantExpr>(WU);
+          if (!CExpr || !replaceConstantExprOp(CExpr, P))
+            return false;
+        }
+      }
+  } while (CE->hasNUsesOrMore(1)); // We need to check because a recursive
+  // sibling may have used 'CE' when createReplacementInstr was called.
+  CE->destroyConstant();
+  return true;
+}
+
+static bool rewriteNonInstructionUses(GlobalVariable *GV, Pass *P) {
+  SmallVector<WeakVH,8> WUsers;
+  for (User *U : GV->users())
+    if (!isa<Instruction>(U))
+      WUsers.push_back(WeakVH(U));
+  while (!WUsers.empty())
+    if (WeakVH WU = WUsers.pop_back_val()) {
+      ConstantExpr *CE = dyn_cast<ConstantExpr>(WU);
+      if (!CE || !replaceConstantExprOp(CE, P))
+        return false;
+    }
+  return true;
+}
+
+static bool isZeroLengthArray(Type *Ty) {
+  ArrayType *AT = dyn_cast<ArrayType>(Ty);
+  return AT && (AT->getNumElements() == 0);
+}
+
+bool XCoreLowerThreadLocal::lowerGlobal(GlobalVariable *GV) {
+  Module *M = GV->getParent();
+  LLVMContext &Ctx = M->getContext();
+  if (!GV->isThreadLocal())
+    return false;
+
+  // Skip globals that we can't lower and leave it for the backend to error.
+  if (!rewriteNonInstructionUses(GV, this) ||
+      !GV->getType()->isSized() || isZeroLengthArray(GV->getType()))
+    return false;
+
+  // Create replacement global.
+  ArrayType *NewType = createLoweredType(GV->getType()->getElementType());
+  Constant *NewInitializer = nullptr;
+  if (GV->hasInitializer())
+    NewInitializer = createLoweredInitializer(NewType,
+                                              GV->getInitializer());
+  GlobalVariable *NewGV =
+    new GlobalVariable(*M, NewType, GV->isConstant(), GV->getLinkage(),
+                       NewInitializer, "", nullptr,
+                       GlobalVariable::NotThreadLocal,
+                       GV->getType()->getAddressSpace(),
+                       GV->isExternallyInitialized());
+
+  // Update uses.
+  SmallVector<User *, 16> Users(GV->user_begin(), GV->user_end());
+  for (unsigned I = 0, E = Users.size(); I != E; ++I) {
+    User *U = Users[I];
+    Instruction *Inst = cast<Instruction>(U);
+    IRBuilder<> Builder(Inst);
+    Function *GetID = Intrinsic::getDeclaration(GV->getParent(),
+                                                Intrinsic::xcore_getid);
+    Value *ThreadID = Builder.CreateCall(GetID, {});
+    SmallVector<Value *, 2> Indices;
+    Indices.push_back(Constant::getNullValue(Type::getInt64Ty(Ctx)));
+    Indices.push_back(ThreadID);
+    Value *Addr =
+        Builder.CreateInBoundsGEP(NewGV->getValueType(), NewGV, Indices);
+    U->replaceUsesOfWith(GV, Addr);
+  }
+
+  // Remove old global.
+  NewGV->takeName(GV);
+  GV->eraseFromParent();
+  return true;
+}
+
+bool XCoreLowerThreadLocal::runOnModule(Module &M) {
+  // Find thread local globals.
+  bool MadeChange = false;
+  SmallVector<GlobalVariable *, 16> ThreadLocalGlobals;
+  for (GlobalVariable &GV : M.globals())
+    if (GV.isThreadLocal())
+      ThreadLocalGlobals.push_back(&GV);
+  for (unsigned I = 0, E = ThreadLocalGlobals.size(); I != E; ++I) {
+    MadeChange |= lowerGlobal(ThreadLocalGlobals[I]);
+  }
+  return MadeChange;
+}