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diff --git a/contrib/llvm/lib/Target/X86/X86CallFrameOptimization.cpp b/contrib/llvm/lib/Target/X86/X86CallFrameOptimization.cpp
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+++ b/contrib/llvm/lib/Target/X86/X86CallFrameOptimization.cpp
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+//===----- X86CallFrameOptimization.cpp - Optimize x86 call sequences -----===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines a pass that optimizes call sequences on x86.
+// Currently, it converts movs of function parameters onto the stack into 
+// pushes. This is beneficial for two main reasons:
+// 1) The push instruction encoding is much smaller than an esp-relative mov
+// 2) It is possible to push memory arguments directly. So, if the
+//    the transformation is preformed pre-reg-alloc, it can help relieve
+//    register pressure.
+//
+//===----------------------------------------------------------------------===//
+
+#include <algorithm>
+
+#include "X86.h"
+#include "X86InstrInfo.h"
+#include "X86Subtarget.h"
+#include "X86MachineFunctionInfo.h"
+#include "llvm/ADT/Statistic.h"
+#include "llvm/CodeGen/MachineFunctionPass.h"
+#include "llvm/CodeGen/MachineInstrBuilder.h"
+#include "llvm/CodeGen/MachineRegisterInfo.h"
+#include "llvm/CodeGen/Passes.h"
+#include "llvm/IR/Function.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/Target/TargetInstrInfo.h"
+
+using namespace llvm;
+
+#define DEBUG_TYPE "x86-cf-opt"
+
+cl::opt<bool> NoX86CFOpt("no-x86-call-frame-opt",
+              cl::desc("Avoid optimizing x86 call frames for size"),
+              cl::init(false), cl::Hidden);
+
+namespace {
+class X86CallFrameOptimization : public MachineFunctionPass {
+public:
+  X86CallFrameOptimization() : MachineFunctionPass(ID) {}
+
+  bool runOnMachineFunction(MachineFunction &MF) override;
+
+private:
+  bool shouldPerformTransformation(MachineFunction &MF);
+
+  bool adjustCallSequence(MachineFunction &MF, MachineBasicBlock &MBB,
+                          MachineBasicBlock::iterator I);
+
+  MachineInstr *canFoldIntoRegPush(MachineBasicBlock::iterator FrameSetup,
+                                   unsigned Reg);
+
+  const char *getPassName() const override {
+    return "X86 Optimize Call Frame";
+  }
+
+  const TargetInstrInfo *TII;
+  const TargetFrameLowering *TFL;
+  const MachineRegisterInfo *MRI;
+  static char ID;
+};
+
+char X86CallFrameOptimization::ID = 0;
+}
+
+FunctionPass *llvm::createX86CallFrameOptimization() {
+  return new X86CallFrameOptimization();
+}
+
+// This checks whether the transformation is legal and profitable
+bool X86CallFrameOptimization::shouldPerformTransformation(MachineFunction &MF) {
+  if (NoX86CFOpt.getValue())
+    return false;
+
+  // We currently only support call sequences where *all* parameters.
+  // are passed on the stack.
+  // No point in running this in 64-bit mode, since some arguments are
+  // passed in-register in all common calling conventions, so the pattern
+  // we're looking for will never match.
+  const X86Subtarget &STI = MF.getTarget().getSubtarget<X86Subtarget>();
+  if (STI.is64Bit())
+    return false;
+
+  // You would expect straight-line code between call-frame setup and
+  // call-frame destroy. You would be wrong. There are circumstances (e.g.
+  // CMOV_GR8 expansion of a select that feeds a function call!) where we can
+  // end up with the setup and the destroy in different basic blocks.
+  // This is bad, and breaks SP adjustment.
+  // So, check that all of the frames in the function are closed inside
+  // the same block, and, for good measure, that there are no nested frames.
+  int FrameSetupOpcode = TII->getCallFrameSetupOpcode();
+  int FrameDestroyOpcode = TII->getCallFrameDestroyOpcode();
+  for (MachineBasicBlock &BB : MF) {
+    bool InsideFrameSequence = false;
+    for (MachineInstr &MI : BB) {
+      if (MI.getOpcode() == FrameSetupOpcode) {
+        if (InsideFrameSequence)
+          return false;
+        InsideFrameSequence = true;
+      }
+      else if (MI.getOpcode() == FrameDestroyOpcode) {
+        if (!InsideFrameSequence)
+          return false;
+        InsideFrameSequence = false;
+      }
+    }
+
+    if (InsideFrameSequence)
+      return false;
+  }
+
+  // Now that we know the transformation is legal, check if it is
+  // profitable.
+  // TODO: Add a heuristic that actually looks at the function,
+  //       and enable this for more cases.
+
+  // This transformation is always a win when we expected to have
+  // a reserved call frame. Under other circumstances, it may be either 
+  // a win or a loss, and requires a heuristic.
+  // For now, enable it only for the relatively clear win cases.
+  bool CannotReserveFrame = MF.getFrameInfo()->hasVarSizedObjects();
+  if (CannotReserveFrame)
+    return true;
+
+  // For now, don't even try to evaluate the profitability when
+  // not optimizing for size.
+  AttributeSet FnAttrs = MF.getFunction()->getAttributes();
+  bool OptForSize =
+    FnAttrs.hasAttribute(AttributeSet::FunctionIndex,
+    Attribute::OptimizeForSize) ||
+    FnAttrs.hasAttribute(AttributeSet::FunctionIndex, Attribute::MinSize);
+
+  if (!OptForSize)
+    return false;
+
+  // Stack re-alignment can make this unprofitable even in terms of size.
+  // As mentioned above, a better heuristic is needed. For now, don't do this
+  // when the required alignment is above 8. (4 would be the safe choice, but
+  // some experimentation showed 8 is generally good).
+  if (TFL->getStackAlignment() > 8)
+    return false;
+
+  return true;
+}
+
+bool X86CallFrameOptimization::runOnMachineFunction(MachineFunction &MF) {
+  TII = MF.getSubtarget().getInstrInfo();
+  TFL = MF.getSubtarget().getFrameLowering();
+  MRI = &MF.getRegInfo();
+
+  if (!shouldPerformTransformation(MF))
+    return false;
+
+  int FrameSetupOpcode = TII->getCallFrameSetupOpcode();
+
+  bool Changed = false;
+
+  for (MachineFunction::iterator BB = MF.begin(), E = MF.end(); BB != E; ++BB)
+    for (MachineBasicBlock::iterator I = BB->begin(); I != BB->end(); ++I)
+      if (I->getOpcode() == FrameSetupOpcode)
+        Changed |= adjustCallSequence(MF, *BB, I);
+
+  return Changed;
+}
+
+bool X86CallFrameOptimization::adjustCallSequence(MachineFunction &MF,
+                                                MachineBasicBlock &MBB,
+                                                MachineBasicBlock::iterator I) {
+
+  // Check that this particular call sequence is amenable to the
+  // transformation.
+  const X86RegisterInfo &RegInfo = *static_cast<const X86RegisterInfo *>(
+                                       MF.getSubtarget().getRegisterInfo());
+  unsigned StackPtr = RegInfo.getStackRegister();
+  int FrameDestroyOpcode = TII->getCallFrameDestroyOpcode();
+
+  // We expect to enter this at the beginning of a call sequence
+  assert(I->getOpcode() == TII->getCallFrameSetupOpcode());
+  MachineBasicBlock::iterator FrameSetup = I++;
+
+  
+  // For globals in PIC mode, we can have some LEAs here.
+  // Ignore them, they don't bother us.
+  // TODO: Extend this to something that covers more cases.
+  while (I->getOpcode() == X86::LEA32r)
+    ++I;
+  
+  // We expect a copy instruction here.
+  // TODO: The copy instruction is a lowering artifact.
+  //       We should also support a copy-less version, where the stack
+  //       pointer is used directly.
+  if (!I->isCopy() || !I->getOperand(0).isReg())
+    return false;
+  MachineBasicBlock::iterator SPCopy = I++;
+  StackPtr = SPCopy->getOperand(0).getReg();
+
+  // Scan the call setup sequence for the pattern we're looking for.
+  // We only handle a simple case - a sequence of MOV32mi or MOV32mr
+  // instructions, that push a sequence of 32-bit values onto the stack, with
+  // no gaps between them.
+  SmallVector<MachineInstr*, 4> MovVector(4, nullptr);
+  unsigned int MaxAdjust = FrameSetup->getOperand(0).getImm() / 4;
+  if (MaxAdjust > 4)
+    MovVector.resize(MaxAdjust, nullptr);
+
+  do {
+    int Opcode = I->getOpcode();
+    if (Opcode != X86::MOV32mi && Opcode != X86::MOV32mr)
+      break;
+
+    // We only want movs of the form:
+    // movl imm/r32, k(%esp)
+    // If we run into something else, bail.
+    // Note that AddrBaseReg may, counter to its name, not be a register,
+    // but rather a frame index.
+    // TODO: Support the fi case. This should probably work now that we
+    // have the infrastructure to track the stack pointer within a call
+    // sequence.
+    if (!I->getOperand(X86::AddrBaseReg).isReg() ||
+        (I->getOperand(X86::AddrBaseReg).getReg() != StackPtr) ||
+        !I->getOperand(X86::AddrScaleAmt).isImm() ||
+        (I->getOperand(X86::AddrScaleAmt).getImm() != 1) ||
+        (I->getOperand(X86::AddrIndexReg).getReg() != X86::NoRegister) ||
+        (I->getOperand(X86::AddrSegmentReg).getReg() != X86::NoRegister) ||
+        !I->getOperand(X86::AddrDisp).isImm())
+      return false;
+
+    int64_t StackDisp = I->getOperand(X86::AddrDisp).getImm();
+    assert(StackDisp >= 0 && "Negative stack displacement when passing parameters");
+
+    // We really don't want to consider the unaligned case.
+    if (StackDisp % 4)
+      return false;
+    StackDisp /= 4;
+
+    assert((size_t)StackDisp < MovVector.size() &&
+      "Function call has more parameters than the stack is adjusted for.");
+
+    // If the same stack slot is being filled twice, something's fishy.
+    if (MovVector[StackDisp] != nullptr)
+      return false;
+    MovVector[StackDisp] = I;
+
+    ++I;
+  } while (I != MBB.end());
+
+  // We now expect the end of the sequence - a call and a stack adjust.
+  if (I == MBB.end())
+    return false;
+
+  // For PCrel calls, we expect an additional COPY of the basereg.
+  // If we find one, skip it.
+  if (I->isCopy()) {
+    if (I->getOperand(1).getReg() ==
+      MF.getInfo<X86MachineFunctionInfo>()->getGlobalBaseReg())
+      ++I;
+    else
+      return false;
+  }
+
+  if (!I->isCall())
+    return false;
+  MachineBasicBlock::iterator Call = I;
+  if ((++I)->getOpcode() != FrameDestroyOpcode)
+    return false;
+
+  // Now, go through the vector, and see that we don't have any gaps,
+  // but only a series of 32-bit MOVs.
+  
+  int64_t ExpectedDist = 0;
+  auto MMI = MovVector.begin(), MME = MovVector.end();
+  for (; MMI != MME; ++MMI, ExpectedDist += 4)
+    if (*MMI == nullptr)
+      break;
+  
+  // If the call had no parameters, do nothing
+  if (!ExpectedDist)
+    return false;
+
+  // We are either at the last parameter, or a gap. 
+  // Make sure it's not a gap
+  for (; MMI != MME; ++MMI)
+    if (*MMI != nullptr)
+      return false;
+
+  // Ok, we can in fact do the transformation for this call.
+  // Do not remove the FrameSetup instruction, but adjust the parameters.
+  // PEI will end up finalizing the handling of this.
+  FrameSetup->getOperand(1).setImm(ExpectedDist);
+
+  DebugLoc DL = I->getDebugLoc();
+  // Now, iterate through the vector in reverse order, and replace the movs
+  // with pushes. MOVmi/MOVmr doesn't have any defs, so no need to 
+  // replace uses.
+  for (int Idx = (ExpectedDist / 4) - 1; Idx >= 0; --Idx) {
+    MachineBasicBlock::iterator MOV = *MovVector[Idx];
+    MachineOperand PushOp = MOV->getOperand(X86::AddrNumOperands);
+    if (MOV->getOpcode() == X86::MOV32mi) {
+      unsigned PushOpcode = X86::PUSHi32;
+      // If the operand is a small (8-bit) immediate, we can use a
+      // PUSH instruction with a shorter encoding.
+      // Note that isImm() may fail even though this is a MOVmi, because
+      // the operand can also be a symbol.
+      if (PushOp.isImm()) {
+        int64_t Val = PushOp.getImm();
+        if (isInt<8>(Val))
+          PushOpcode = X86::PUSH32i8;
+      }
+      BuildMI(MBB, Call, DL, TII->get(PushOpcode)).addOperand(PushOp);
+    } else {
+      unsigned int Reg = PushOp.getReg();
+
+      // If PUSHrmm is not slow on this target, try to fold the source of the
+      // push into the instruction.
+      const X86Subtarget &ST = MF.getTarget().getSubtarget<X86Subtarget>();
+      bool SlowPUSHrmm = ST.isAtom() || ST.isSLM();
+
+      // Check that this is legal to fold. Right now, we're extremely
+      // conservative about that.
+      MachineInstr *DefMov = nullptr;
+      if (!SlowPUSHrmm && (DefMov = canFoldIntoRegPush(FrameSetup, Reg))) {
+        MachineInstr *Push = BuildMI(MBB, Call, DL, TII->get(X86::PUSH32rmm));
+
+        unsigned NumOps = DefMov->getDesc().getNumOperands();
+        for (unsigned i = NumOps - X86::AddrNumOperands; i != NumOps; ++i)
+          Push->addOperand(DefMov->getOperand(i));
+
+        DefMov->eraseFromParent();
+      } else {
+        BuildMI(MBB, Call, DL, TII->get(X86::PUSH32r)).addReg(Reg).getInstr();
+      }
+    }
+
+    MBB.erase(MOV);
+  }
+
+  // The stack-pointer copy is no longer used in the call sequences.
+  // There should not be any other users, but we can't commit to that, so:
+  if (MRI->use_empty(SPCopy->getOperand(0).getReg()))
+    SPCopy->eraseFromParent();
+
+  // Once we've done this, we need to make sure PEI doesn't assume a reserved
+  // frame.
+  X86MachineFunctionInfo *FuncInfo = MF.getInfo<X86MachineFunctionInfo>();
+  FuncInfo->setHasPushSequences(true);
+
+  return true;
+}
+
+MachineInstr *X86CallFrameOptimization::canFoldIntoRegPush(
+    MachineBasicBlock::iterator FrameSetup, unsigned Reg) {
+  // Do an extremely restricted form of load folding.
+  // ISel will often create patterns like:
+  // movl    4(%edi), %eax
+  // movl    8(%edi), %ecx
+  // movl    12(%edi), %edx
+  // movl    %edx, 8(%esp)
+  // movl    %ecx, 4(%esp)
+  // movl    %eax, (%esp)
+  // call
+  // Get rid of those with prejudice.
+  if (!TargetRegisterInfo::isVirtualRegister(Reg))
+    return nullptr;
+
+  // Make sure this is the only use of Reg.
+  if (!MRI->hasOneNonDBGUse(Reg))
+    return nullptr;
+
+  MachineBasicBlock::iterator DefMI = MRI->getVRegDef(Reg);
+
+  // Make sure the def is a MOV from memory.
+  // If the def is an another block, give up.
+  if (DefMI->getOpcode() != X86::MOV32rm ||
+      DefMI->getParent() != FrameSetup->getParent())
+    return nullptr;
+
+  // Be careful with movs that load from a stack slot, since it may get
+  // resolved incorrectly.
+  // TODO: Again, we already have the infrastructure, so this should work.
+  if (!DefMI->getOperand(1).isReg())
+    return nullptr;
+
+  // Now, make sure everything else up until the ADJCALLSTACK is a sequence
+  // of MOVs. To be less conservative would require duplicating a lot of the
+  // logic from PeepholeOptimizer.
+  // FIXME: A possibly better approach would be to teach the PeepholeOptimizer
+  // to be smarter about folding into pushes. 
+  for (auto I = DefMI; I != FrameSetup; ++I)
+    if (I->getOpcode() != X86::MOV32rm)
+      return nullptr;
+
+  return DefMI;
+}