Update clang, llvm, lld, lldb, compiler-rt and libc++ to 4.0.0 release:

MFC r309142 (by emaste):

Add WITH_LLD_AS_LD build knob

If set it installs LLD as /usr/bin/ld.  LLD (as of version 3.9) is not
capable of linking the world and kernel, but can self-host and link many
substantial applications. GNU ld continues to be used for the world and
kernel build, regardless of how this knob is set.

It is on by default for arm64, and off for all other CPU architectures.

Sponsored by:	The FreeBSD Foundation

MFC r310840:

Reapply 310775, now it also builds correctly if lldb is disabled:

Move llvm-objdump from CLANG_EXTRAS to installed by default

We currently install three tools from binutils 2.17.50: as, ld, and
objdump. Work is underway to migrate to a permissively-licensed
tool-chain, with one goal being the retirement of binutils 2.17.50.

LLVM's llvm-objdump is intended to be compatible with GNU objdump
although it is currently missing some options and may have formatting
differences. Enable it by default for testing and further investigation.
It may later be changed to install as /usr/bin/objdump, it becomes a
fully viable replacement.

Reviewed by:	emaste
Differential Revision:	https://reviews.freebsd.org/D8879

MFC r312855 (by emaste):

Rename LLD_AS_LD to LLD_IS_LD, for consistency with CLANG_IS_CC

Reported by:	Dan McGregor <dan.mcgregor usask.ca>

MFC r313559 | glebius | 2017-02-10 18:34:48 +0100 (Fri, 10 Feb 2017) | 5 lines

Don't check struct rtentry on FreeBSD, it is an internal kernel structure.
On other systems it may be API structure for SIOCADDRT/SIOCDELRT.

Reviewed by:	emaste, dim

MFC r314152 (by jkim):

Remove an assembler flag, which is redundant since r309124.  The upstream
took care of it by introducing a macro NO_EXEC_STACK_DIRECTIVE.

http://llvm.org/viewvc/llvm-project?rev=273500&view=rev

Reviewed by:	dim

MFC r314564:

Upgrade our copies of clang, llvm, lld, lldb, compiler-rt and libc++ to
4.0.0 (branches/release_40 296509).  The release will follow soon.

Please note that from 3.5.0 onwards, clang, llvm and lldb require C++11
support to build; see UPDATING for more information.

Also note that as of 4.0.0, lld should be able to link the base system
on amd64 and aarch64.  See the WITH_LLD_IS_LLD setting in src.conf(5).
Though please be aware that this is work in progress.

Release notes for llvm, clang and lld will be available here:
<http://releases.llvm.org/4.0.0/docs/ReleaseNotes.html>
<http://releases.llvm.org/4.0.0/tools/clang/docs/ReleaseNotes.html>
<http://releases.llvm.org/4.0.0/tools/lld/docs/ReleaseNotes.html>

Thanks to Ed Maste, Jan Beich, Antoine Brodin and Eric Fiselier for
their help.

Relnotes:	yes
Exp-run:	antoine
PR:		215969, 216008

MFC r314708:

For now, revert r287232 from upstream llvm trunk (by Daniil Fukalov):

  [SCEV] limit recursion depth of CompareSCEVComplexity

  Summary:
  CompareSCEVComplexity goes too deep (50+ on a quite a big unrolled
  loop) and runs almost infinite time.

  Added cache of "equal" SCEV pairs to earlier cutoff of further
  estimation. Recursion depth limit was also introduced as a parameter.

  Reviewers: sanjoy

  Subscribers: mzolotukhin, tstellarAMD, llvm-commits

  Differential Revision: https://reviews.llvm.org/D26389

This commit is the cause of excessive compile times on skein_block.c
(and possibly other files) during kernel builds on amd64.

We never saw the problematic behavior described in this upstream commit,
so for now it is better to revert it.  An upstream bug has been filed
here: https://bugs.llvm.org/show_bug.cgi?id=32142

Reported by:	mjg

MFC r314795:

Reapply r287232 from upstream llvm trunk (by Daniil Fukalov):

  [SCEV] limit recursion depth of CompareSCEVComplexity

  Summary:
  CompareSCEVComplexity goes too deep (50+ on a quite a big unrolled
  loop) and runs almost infinite time.

  Added cache of "equal" SCEV pairs to earlier cutoff of further
  estimation. Recursion depth limit was also introduced as a parameter.

  Reviewers: sanjoy

  Subscribers: mzolotukhin, tstellarAMD, llvm-commits

  Differential Revision: https://reviews.llvm.org/D26389

Pull in r296992 from upstream llvm trunk (by Sanjoy Das):

  [SCEV] Decrease the recursion threshold for CompareValueComplexity

  Fixes PR32142.

  r287232 accidentally increased the recursion threshold for
  CompareValueComplexity from 2 to 32.  This change reverses that
  change by introducing a separate flag for CompareValueComplexity's
  threshold.

The latter revision fixes the excessive compile times for skein_block.c.

MFC r314907 | mmel | 2017-03-08 12:40:27 +0100 (Wed, 08 Mar 2017) | 7 lines

Unbreak ARMv6 world.

The new compiler_rt library imported with clang 4.0.0 have several fatal
issues (non-functional __udivsi3 for example) with ARM specific instrict
functions. As temporary workaround, until upstream solve these problems,
disable all thumb[1][2] related feature.

MFC r315016:

Update clang, llvm, lld, lldb, compiler-rt and libc++ to 4.0.0 release.
We were already very close to the last release candidate, so this is a
pretty minor update.

Relnotes:	yes

MFC r316005:

Revert r314907, and pull in r298713 from upstream compiler-rt trunk (by
Weiming Zhao):

  builtins: Select correct code fragments when compiling for Thumb1/Thum2/ARM ISA.

  Summary:
  Value of __ARM_ARCH_ISA_THUMB isn't based on the actual compilation
  mode (-mthumb, -marm), it reflect's capability of given CPU.

  Due to this:
   - use  __tbumb__ and __thumb2__ insteand of __ARM_ARCH_ISA_THUMB
   - use '.thumb' directive consistently  in all affected files
   - decorate all thumb functions using
     DEFINE_COMPILERRT_THUMB_FUNCTION()

  ---------
  Note: This patch doesn't fix broken Thumb1 variant of __udivsi3 !

  Reviewers: weimingz, rengolin, compnerd

  Subscribers: aemerson, dim

  Differential Revision: https://reviews.llvm.org/D30938

Discussed with:	mmel

1 files changed, 565 insertions, 0 deletions

diff --git a/contrib/llvm/lib/Target/AVR/AVRISelDAGToDAG.cpp b/contrib/llvm/lib/Target/AVR/AVRISelDAGToDAG.cpp
new file mode 100644
index 0000000..462a7d5
--- /dev/null
+++ b/contrib/llvm/lib/Target/AVR/AVRISelDAGToDAG.cpp
@@ -0,0 +1,565 @@
+//===-- AVRISelDAGToDAG.cpp - A dag to dag inst selector for AVR ----------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines an instruction selector for the AVR target.
+//
+//===----------------------------------------------------------------------===//
+
+#include "AVR.h"
+#include "AVRTargetMachine.h"
+#include "MCTargetDesc/AVRMCTargetDesc.h"
+
+#include "llvm/CodeGen/MachineRegisterInfo.h"
+#include "llvm/CodeGen/SelectionDAGISel.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/raw_ostream.h"
+
+#define DEBUG_TYPE "avr-isel"
+
+namespace llvm {
+
+/// Lowers LLVM IR (in DAG form) to AVR MC instructions (in DAG form).
+class AVRDAGToDAGISel : public SelectionDAGISel {
+public:
+  AVRDAGToDAGISel(AVRTargetMachine &TM, CodeGenOpt::Level OptLevel)
+      : SelectionDAGISel(TM, OptLevel), Subtarget(nullptr) {}
+
+  StringRef getPassName() const override {
+    return "AVR DAG->DAG Instruction Selection";
+  }
+
+  bool runOnMachineFunction(MachineFunction &MF) override;
+
+  bool SelectAddr(SDNode *Op, SDValue N, SDValue &Base, SDValue &Disp);
+
+  bool selectIndexedLoad(SDNode *N);
+  unsigned selectIndexedProgMemLoad(const LoadSDNode *LD, MVT VT);
+
+  bool SelectInlineAsmMemoryOperand(const SDValue &Op, unsigned ConstraintCode,
+                                    std::vector<SDValue> &OutOps) override;
+
+// Include the pieces autogenerated from the target description.
+#include "AVRGenDAGISel.inc"
+
+private:
+  void Select(SDNode *N) override;
+  bool trySelect(SDNode *N);
+
+  template <unsigned NodeType> bool select(SDNode *N);
+  bool selectMultiplication(SDNode *N);
+
+  const AVRSubtarget *Subtarget;
+};
+
+bool AVRDAGToDAGISel::runOnMachineFunction(MachineFunction &MF) {
+  Subtarget = &MF.getSubtarget<AVRSubtarget>();
+  return SelectionDAGISel::runOnMachineFunction(MF);
+}
+
+bool AVRDAGToDAGISel::SelectAddr(SDNode *Op, SDValue N, SDValue &Base,
+                                 SDValue &Disp) {
+  SDLoc dl(Op);
+  auto DL = CurDAG->getDataLayout();
+  MVT PtrVT = getTargetLowering()->getPointerTy(DL);
+
+  // if the address is a frame index get the TargetFrameIndex.
+  if (const FrameIndexSDNode *FIN = dyn_cast<FrameIndexSDNode>(N)) {
+    Base = CurDAG->getTargetFrameIndex(FIN->getIndex(), PtrVT);
+    Disp = CurDAG->getTargetConstant(0, dl, MVT::i8);
+
+    return true;
+  }
+
+  // Match simple Reg + uimm6 operands.
+  if (N.getOpcode() != ISD::ADD && N.getOpcode() != ISD::SUB &&
+      !CurDAG->isBaseWithConstantOffset(N)) {
+    return false;
+  }
+
+  if (const ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(N.getOperand(1))) {
+    int RHSC = (int)RHS->getZExtValue();
+
+    // Convert negative offsets into positives ones.
+    if (N.getOpcode() == ISD::SUB) {
+      RHSC = -RHSC;
+    }
+
+    // <#Frame index + const>
+    // Allow folding offsets bigger than 63 so the frame pointer can be used
+    // directly instead of copying it around by adjusting and restoring it for
+    // each access.
+    if (N.getOperand(0).getOpcode() == ISD::FrameIndex) {
+      int FI = cast<FrameIndexSDNode>(N.getOperand(0))->getIndex();
+
+      Base = CurDAG->getTargetFrameIndex(FI, PtrVT);
+      Disp = CurDAG->getTargetConstant(RHSC, dl, MVT::i16);
+
+      return true;
+    }
+
+    // The value type of the memory instruction determines what is the maximum
+    // offset allowed.
+    MVT VT = cast<MemSDNode>(Op)->getMemoryVT().getSimpleVT();
+
+    // We only accept offsets that fit in 6 bits (unsigned).
+    if (isUInt<6>(RHSC) && (VT == MVT::i8 || VT == MVT::i16)) {
+      Base = N.getOperand(0);
+      Disp = CurDAG->getTargetConstant(RHSC, dl, MVT::i8);
+
+      return true;
+    }
+  }
+
+  return false;
+}
+
+bool AVRDAGToDAGISel::selectIndexedLoad(SDNode *N) {
+  const LoadSDNode *LD = cast<LoadSDNode>(N);
+  ISD::MemIndexedMode AM = LD->getAddressingMode();
+  MVT VT = LD->getMemoryVT().getSimpleVT();
+  auto PtrVT = getTargetLowering()->getPointerTy(CurDAG->getDataLayout());
+
+  // We only care if this load uses a POSTINC or PREDEC mode.
+  if ((LD->getExtensionType() != ISD::NON_EXTLOAD) ||
+      (AM != ISD::POST_INC && AM != ISD::PRE_DEC)) {
+
+    return false;
+  }
+
+  unsigned Opcode = 0;
+  bool isPre = (AM == ISD::PRE_DEC);
+  int Offs = cast<ConstantSDNode>(LD->getOffset())->getSExtValue();
+
+  switch (VT.SimpleTy) {
+  case MVT::i8: {
+    if ((!isPre && Offs != 1) || (isPre && Offs != -1)) {
+      return false;
+    }
+
+    Opcode = (isPre) ? AVR::LDRdPtrPd : AVR::LDRdPtrPi;
+    break;
+  }
+  case MVT::i16: {
+    if ((!isPre && Offs != 2) || (isPre && Offs != -2)) {
+      return false;
+    }
+
+    Opcode = (isPre) ? AVR::LDWRdPtrPd : AVR::LDWRdPtrPi;
+    break;
+  }
+  default:
+    return false;
+  }
+
+  SDNode *ResNode = CurDAG->getMachineNode(Opcode, SDLoc(N), VT,
+                                           PtrVT, MVT::Other,
+                                           LD->getBasePtr(), LD->getChain());
+  ReplaceUses(N, ResNode);
+  CurDAG->RemoveDeadNode(N);
+
+  return true;
+}
+
+unsigned AVRDAGToDAGISel::selectIndexedProgMemLoad(const LoadSDNode *LD,
+                                                   MVT VT) {
+  ISD::MemIndexedMode AM = LD->getAddressingMode();
+
+  // Progmem indexed loads only work in POSTINC mode.
+  if (LD->getExtensionType() != ISD::NON_EXTLOAD || AM != ISD::POST_INC) {
+    return 0;
+  }
+
+  unsigned Opcode = 0;
+  int Offs = cast<ConstantSDNode>(LD->getOffset())->getSExtValue();
+
+  switch (VT.SimpleTy) {
+  case MVT::i8: {
+    if (Offs != 1) {
+      return 0;
+    }
+    Opcode = AVR::LPMRdZPi;
+    break;
+  }
+  case MVT::i16: {
+    if (Offs != 2) {
+      return 0;
+    }
+    Opcode = AVR::LPMWRdZPi;
+    break;
+  }
+  default:
+    return 0;
+  }
+
+  return Opcode;
+}
+
+bool AVRDAGToDAGISel::SelectInlineAsmMemoryOperand(const SDValue &Op,
+                                                   unsigned ConstraintCode,
+                                                   std::vector<SDValue> &OutOps) {
+  assert((ConstraintCode == InlineAsm::Constraint_m ||
+         ConstraintCode == InlineAsm::Constraint_Q) &&
+      "Unexpected asm memory constraint");
+
+  MachineRegisterInfo &RI = MF->getRegInfo();
+  const AVRSubtarget &STI = MF->getSubtarget<AVRSubtarget>();
+  const TargetLowering &TL = *STI.getTargetLowering();
+  SDLoc dl(Op);
+  auto DL = CurDAG->getDataLayout();
+
+  const RegisterSDNode *RegNode = dyn_cast<RegisterSDNode>(Op);
+
+  // If address operand is of PTRDISPREGS class, all is OK, then.
+  if (RegNode &&
+      RI.getRegClass(RegNode->getReg()) == &AVR::PTRDISPREGSRegClass) {
+    OutOps.push_back(Op);
+    return false;
+  }
+
+  if (Op->getOpcode() == ISD::FrameIndex) {
+    SDValue Base, Disp;
+
+    if (SelectAddr(Op.getNode(), Op, Base, Disp)) {
+      OutOps.push_back(Base);
+      OutOps.push_back(Disp);
+
+      return false;
+    }
+
+    return true;
+  }
+
+  // If Op is add 'register, immediate' and
+  // register is either virtual register or register of PTRDISPREGSRegClass
+  if (Op->getOpcode() == ISD::ADD || Op->getOpcode() == ISD::SUB) {
+    SDValue CopyFromRegOp = Op->getOperand(0);
+    SDValue ImmOp = Op->getOperand(1);
+    ConstantSDNode *ImmNode = dyn_cast<ConstantSDNode>(ImmOp);
+
+    unsigned Reg;
+    bool CanHandleRegImmOpt = true;
+
+    CanHandleRegImmOpt &= ImmNode != 0;
+    CanHandleRegImmOpt &= ImmNode->getAPIntValue().getZExtValue() < 64;
+
+    if (CopyFromRegOp->getOpcode() == ISD::CopyFromReg) {
+      RegisterSDNode *RegNode =
+          cast<RegisterSDNode>(CopyFromRegOp->getOperand(1));
+      Reg = RegNode->getReg();
+      CanHandleRegImmOpt &= (TargetRegisterInfo::isVirtualRegister(Reg) ||
+                             AVR::PTRDISPREGSRegClass.contains(Reg));
+    } else {
+      CanHandleRegImmOpt = false;
+    }
+
+    // If we detect proper case - correct virtual register class
+    // if needed and go to another inlineasm operand.
+    if (CanHandleRegImmOpt) {
+      SDValue Base, Disp;
+
+      if (RI.getRegClass(Reg) != &AVR::PTRDISPREGSRegClass) {
+        SDLoc dl(CopyFromRegOp);
+
+        unsigned VReg = RI.createVirtualRegister(&AVR::PTRDISPREGSRegClass);
+
+        SDValue CopyToReg =
+            CurDAG->getCopyToReg(CopyFromRegOp, dl, VReg, CopyFromRegOp);
+
+        SDValue NewCopyFromRegOp =
+            CurDAG->getCopyFromReg(CopyToReg, dl, VReg, TL.getPointerTy(DL));
+
+        Base = NewCopyFromRegOp;
+      } else {
+        Base = CopyFromRegOp;
+      }
+
+      if (ImmNode->getValueType(0) != MVT::i8) {
+        Disp = CurDAG->getTargetConstant(ImmNode->getAPIntValue().getZExtValue(), dl, MVT::i8);
+      } else {
+        Disp = ImmOp;
+      }
+
+      OutOps.push_back(Base);
+      OutOps.push_back(Disp);
+
+      return false;
+    }
+  }
+
+  // More generic case.
+  // Create chain that puts Op into pointer register
+  // and return that register.
+  unsigned VReg = RI.createVirtualRegister(&AVR::PTRDISPREGSRegClass);
+
+  SDValue CopyToReg = CurDAG->getCopyToReg(Op, dl, VReg, Op);
+  SDValue CopyFromReg =
+      CurDAG->getCopyFromReg(CopyToReg, dl, VReg, TL.getPointerTy(DL));
+
+  OutOps.push_back(CopyFromReg);
+
+  return false;
+}
+
+template <> bool AVRDAGToDAGISel::select<ISD::FrameIndex>(SDNode *N) {
+  auto DL = CurDAG->getDataLayout();
+
+  // Convert the frameindex into a temp instruction that will hold the
+  // effective address of the final stack slot.
+  int FI = cast<FrameIndexSDNode>(N)->getIndex();
+  SDValue TFI =
+    CurDAG->getTargetFrameIndex(FI, getTargetLowering()->getPointerTy(DL));
+
+  CurDAG->SelectNodeTo(N, AVR::FRMIDX,
+                       getTargetLowering()->getPointerTy(DL), TFI,
+                       CurDAG->getTargetConstant(0, SDLoc(N), MVT::i16));
+  return true;
+}
+
+template <> bool AVRDAGToDAGISel::select<ISD::STORE>(SDNode *N) {
+  // Use the STD{W}SPQRr pseudo instruction when passing arguments through
+  // the stack on function calls for further expansion during the PEI phase.
+  const StoreSDNode *ST = cast<StoreSDNode>(N);
+  SDValue BasePtr = ST->getBasePtr();
+
+  // Early exit when the base pointer is a frame index node or a constant.
+  if (isa<FrameIndexSDNode>(BasePtr) || isa<ConstantSDNode>(BasePtr) ||
+      BasePtr.isUndef()) {
+    return false;
+  }
+
+  const RegisterSDNode *RN = dyn_cast<RegisterSDNode>(BasePtr.getOperand(0));
+  // Only stores where SP is the base pointer are valid.
+  if (!RN || (RN->getReg() != AVR::SP)) {
+    return false;
+  }
+
+  int CST = (int)cast<ConstantSDNode>(BasePtr.getOperand(1))->getZExtValue();
+  SDValue Chain = ST->getChain();
+  EVT VT = ST->getValue().getValueType();
+  SDLoc DL(N);
+  SDValue Offset = CurDAG->getTargetConstant(CST, DL, MVT::i16);
+  SDValue Ops[] = {BasePtr.getOperand(0), Offset, ST->getValue(), Chain};
+  unsigned Opc = (VT == MVT::i16) ? AVR::STDWSPQRr : AVR::STDSPQRr;
+
+  SDNode *ResNode = CurDAG->getMachineNode(Opc, DL, MVT::Other, Ops);
+
+  // Transfer memory operands.
+  MachineSDNode::mmo_iterator MemOp = MF->allocateMemRefsArray(1);
+  MemOp[0] = ST->getMemOperand();
+  cast<MachineSDNode>(ResNode)->setMemRefs(MemOp, MemOp + 1);
+
+  ReplaceUses(SDValue(N, 0), SDValue(ResNode, 0));
+  CurDAG->RemoveDeadNode(N);
+
+  return true;
+}
+
+template <> bool AVRDAGToDAGISel::select<ISD::LOAD>(SDNode *N) {
+  const LoadSDNode *LD = cast<LoadSDNode>(N);
+  if (!AVR::isProgramMemoryAccess(LD)) {
+    // Check if the opcode can be converted into an indexed load.
+    return selectIndexedLoad(N);
+  }
+
+  assert(Subtarget->hasLPM() && "cannot load from program memory on this mcu");
+
+  // This is a flash memory load, move the pointer into R31R30 and emit
+  // the lpm instruction.
+  MVT VT = LD->getMemoryVT().getSimpleVT();
+  SDValue Chain = LD->getChain();
+  SDValue Ptr = LD->getBasePtr();
+  SDNode *ResNode;
+  SDLoc DL(N);
+
+  Chain = CurDAG->getCopyToReg(Chain, DL, AVR::R31R30, Ptr, SDValue());
+  Ptr = CurDAG->getCopyFromReg(Chain, DL, AVR::R31R30, MVT::i16,
+                               Chain.getValue(1));
+
+  SDValue RegZ = CurDAG->getRegister(AVR::R31R30, MVT::i16);
+
+  // Check if the opcode can be converted into an indexed load.
+  if (unsigned LPMOpc = selectIndexedProgMemLoad(LD, VT)) {
+    // It is legal to fold the load into an indexed load.
+    ResNode = CurDAG->getMachineNode(LPMOpc, DL, VT, MVT::i16, MVT::Other, Ptr,
+                                     RegZ);
+    ReplaceUses(SDValue(N, 1), SDValue(ResNode, 1));
+  } else {
+    // Selecting an indexed load is not legal, fallback to a normal load.
+    switch (VT.SimpleTy) {
+    case MVT::i8:
+      ResNode = CurDAG->getMachineNode(AVR::LPMRdZ, DL, MVT::i8, MVT::Other,
+                                       Ptr, RegZ);
+      break;
+    case MVT::i16:
+      ResNode = CurDAG->getMachineNode(AVR::LPMWRdZ, DL, MVT::i16,
+                                       MVT::Other, Ptr, RegZ);
+      ReplaceUses(SDValue(N, 1), SDValue(ResNode, 1));
+      break;
+    default:
+      llvm_unreachable("Unsupported VT!");
+    }
+  }
+
+  // Transfer memory operands.
+  MachineSDNode::mmo_iterator MemOp = MF->allocateMemRefsArray(1);
+  MemOp[0] = LD->getMemOperand();
+  cast<MachineSDNode>(ResNode)->setMemRefs(MemOp, MemOp + 1);
+
+  ReplaceUses(SDValue(N, 0), SDValue(ResNode, 0));
+  ReplaceUses(SDValue(N, 1), SDValue(ResNode, 1));
+  CurDAG->RemoveDeadNode(N);
+
+  return true;
+}
+
+template <> bool AVRDAGToDAGISel::select<AVRISD::CALL>(SDNode *N) {
+  SDValue InFlag;
+  SDValue Chain = N->getOperand(0);
+  SDValue Callee = N->getOperand(1);
+  unsigned LastOpNum = N->getNumOperands() - 1;
+
+  // Direct calls are autogenerated.
+  unsigned Op = Callee.getOpcode();
+  if (Op == ISD::TargetGlobalAddress || Op == ISD::TargetExternalSymbol) {
+    return false;
+  }
+
+  // Skip the incoming flag if present
+  if (N->getOperand(LastOpNum).getValueType() == MVT::Glue) {
+    --LastOpNum;
+  }
+
+  SDLoc DL(N);
+  Chain = CurDAG->getCopyToReg(Chain, DL, AVR::R31R30, Callee, InFlag);
+  SmallVector<SDValue, 8> Ops;
+  Ops.push_back(CurDAG->getRegister(AVR::R31R30, MVT::i16));
+
+  // Map all operands into the new node.
+  for (unsigned i = 2, e = LastOpNum + 1; i != e; ++i) {
+    Ops.push_back(N->getOperand(i));
+  }
+
+  Ops.push_back(Chain);
+  Ops.push_back(Chain.getValue(1));
+
+  SDNode *ResNode =
+    CurDAG->getMachineNode(AVR::ICALL, DL, MVT::Other, MVT::Glue, Ops);
+
+  ReplaceUses(SDValue(N, 0), SDValue(ResNode, 0));
+  ReplaceUses(SDValue(N, 1), SDValue(ResNode, 1));
+  CurDAG->RemoveDeadNode(N);
+
+  return true;
+}
+
+template <> bool AVRDAGToDAGISel::select<ISD::BRIND>(SDNode *N) {
+  SDValue Chain = N->getOperand(0);
+  SDValue JmpAddr = N->getOperand(1);
+
+  SDLoc DL(N);
+  // Move the destination address of the indirect branch into R31R30.
+  Chain = CurDAG->getCopyToReg(Chain, DL, AVR::R31R30, JmpAddr);
+  SDNode *ResNode = CurDAG->getMachineNode(AVR::IJMP, DL, MVT::Other, Chain);
+
+  ReplaceUses(SDValue(N, 0), SDValue(ResNode, 0));
+  CurDAG->RemoveDeadNode(N);
+
+  return true;
+}
+
+bool AVRDAGToDAGISel::selectMultiplication(llvm::SDNode *N) {
+  SDLoc DL(N);
+  MVT Type = N->getSimpleValueType(0);
+
+  assert(Type == MVT::i8 && "unexpected value type");
+
+  bool isSigned = N->getOpcode() == ISD::SMUL_LOHI;
+  unsigned MachineOp = isSigned ? AVR::MULSRdRr : AVR::MULRdRr;
+
+  SDValue Lhs = N->getOperand(0);
+  SDValue Rhs = N->getOperand(1);
+  SDNode *Mul = CurDAG->getMachineNode(MachineOp, DL, MVT::Glue, Lhs, Rhs);
+  SDValue InChain = CurDAG->getEntryNode();
+  SDValue InGlue = SDValue(Mul, 0);
+
+  // Copy the low half of the result, if it is needed.
+  if (N->hasAnyUseOfValue(0)) {
+    SDValue CopyFromLo =
+        CurDAG->getCopyFromReg(InChain, DL, AVR::R0, Type, InGlue);
+
+    ReplaceUses(SDValue(N, 0), CopyFromLo);
+
+    InChain = CopyFromLo.getValue(1);
+    InGlue = CopyFromLo.getValue(2);
+  }
+
+  // Copy the high half of the result, if it is needed.
+  if (N->hasAnyUseOfValue(1)) {
+    SDValue CopyFromHi =
+        CurDAG->getCopyFromReg(InChain, DL, AVR::R1, Type, InGlue);
+
+    ReplaceUses(SDValue(N, 1), CopyFromHi);
+
+    InChain = CopyFromHi.getValue(1);
+    InGlue = CopyFromHi.getValue(2);
+  }
+
+  CurDAG->RemoveDeadNode(N);
+
+  // We need to clear R1. This is currently done (dirtily)
+  // using a custom inserter.
+
+  return true;
+}
+
+void AVRDAGToDAGISel::Select(SDNode *N) {
+  // Dump information about the Node being selected
+  DEBUG(errs() << "Selecting: "; N->dump(CurDAG); errs() << "\n");
+
+  // If we have a custom node, we already have selected!
+  if (N->isMachineOpcode()) {
+    DEBUG(errs() << "== "; N->dump(CurDAG); errs() << "\n");
+    N->setNodeId(-1);
+    return;
+  }
+
+  // See if subclasses can handle this node.
+  if (trySelect(N))
+    return;
+
+  // Select the default instruction
+  SelectCode(N);
+}
+
+bool AVRDAGToDAGISel::trySelect(SDNode *N) {
+  unsigned Opcode = N->getOpcode();
+  SDLoc DL(N);
+
+  switch (Opcode) {
+  // Nodes we fully handle.
+  case ISD::FrameIndex: return select<ISD::FrameIndex>(N);
+  case ISD::BRIND:      return select<ISD::BRIND>(N);
+  case ISD::UMUL_LOHI:
+  case ISD::SMUL_LOHI:  return selectMultiplication(N);
+
+  // Nodes we handle partially. Other cases are autogenerated
+  case ISD::STORE:   return select<ISD::STORE>(N);
+  case ISD::LOAD:    return select<ISD::LOAD>(N);
+  case AVRISD::CALL: return select<AVRISD::CALL>(N);
+  default:           return false;
+  }
+}
+
+FunctionPass *createAVRISelDag(AVRTargetMachine &TM,
+                               CodeGenOpt::Level OptLevel) {
+  return new AVRDAGToDAGISel(TM, OptLevel);
+}
+
+} // end of namespace llvm
+