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diff --git a/contrib/llvm/lib/Target/AVR/AVRRegisterInfo.cpp b/contrib/llvm/lib/Target/AVR/AVRRegisterInfo.cpp
new file mode 100644
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--- /dev/null
+++ b/contrib/llvm/lib/Target/AVR/AVRRegisterInfo.cpp
@@ -0,0 +1,256 @@
+//===-- AVRRegisterInfo.cpp - AVR Register Information --------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains the AVR implementation of the TargetRegisterInfo class.
+//
+//===----------------------------------------------------------------------===//
+
+#include "AVRRegisterInfo.h"
+
+#include "llvm/ADT/BitVector.h"
+#include "llvm/CodeGen/MachineFrameInfo.h"
+#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/CodeGen/MachineInstrBuilder.h"
+#include "llvm/IR/Function.h"
+#include "llvm/Target/TargetFrameLowering.h"
+
+#include "AVR.h"
+#include "AVRInstrInfo.h"
+#include "AVRTargetMachine.h"
+#include "MCTargetDesc/AVRMCTargetDesc.h"
+
+#define GET_REGINFO_TARGET_DESC
+#include "AVRGenRegisterInfo.inc"
+
+namespace llvm {
+
+AVRRegisterInfo::AVRRegisterInfo() : AVRGenRegisterInfo(0) {}
+
+const uint16_t *
+AVRRegisterInfo::getCalleeSavedRegs(const MachineFunction *MF) const {
+  CallingConv::ID CC = MF->getFunction()->getCallingConv();
+
+  return ((CC == CallingConv::AVR_INTR || CC == CallingConv::AVR_SIGNAL)
+              ? CSR_Interrupts_SaveList
+              : CSR_Normal_SaveList);
+}
+
+const uint32_t *
+AVRRegisterInfo::getCallPreservedMask(const MachineFunction &MF,
+                                      CallingConv::ID CC) const {
+  return ((CC == CallingConv::AVR_INTR || CC == CallingConv::AVR_SIGNAL)
+              ? CSR_Interrupts_RegMask
+              : CSR_Normal_RegMask);
+}
+
+BitVector AVRRegisterInfo::getReservedRegs(const MachineFunction &MF) const {
+  BitVector Reserved(getNumRegs());
+  const AVRTargetMachine &TM = static_cast<const AVRTargetMachine&>(MF.getTarget());
+  const TargetFrameLowering *TFI = TM.getSubtargetImpl()->getFrameLowering();
+
+  // Reserve the intermediate result registers r1 and r2
+  // The result of instructions like 'mul' is always stored here.
+  Reserved.set(AVR::R0);
+  Reserved.set(AVR::R1);
+  Reserved.set(AVR::R1R0);
+
+  //  Reserve the stack pointer.
+  Reserved.set(AVR::SPL);
+  Reserved.set(AVR::SPH);
+  Reserved.set(AVR::SP);
+
+  // Reserve the frame pointer registers r28 and r29 if the function requires one.
+  if (TFI->hasFP(MF)) {
+    Reserved.set(AVR::R28);
+    Reserved.set(AVR::R29);
+    Reserved.set(AVR::R29R28);
+  }
+
+  return Reserved;
+}
+
+const TargetRegisterClass *
+AVRRegisterInfo::getLargestLegalSuperClass(const TargetRegisterClass *RC,
+                                           const MachineFunction &MF) const {
+  if (RC->hasType(MVT::i16)) {
+    return &AVR::DREGSRegClass;
+  }
+
+  if (RC->hasType(MVT::i8)) {
+    return &AVR::GPR8RegClass;
+  }
+
+  llvm_unreachable("Invalid register size");
+}
+
+/// Fold a frame offset shared between two add instructions into a single one.
+static void foldFrameOffset(MachineInstr &MI, int &Offset, unsigned DstReg) {
+  int Opcode = MI.getOpcode();
+
+  // Don't bother trying if the next instruction is not an add or a sub.
+  if ((Opcode != AVR::SUBIWRdK) && (Opcode != AVR::ADIWRdK)) {
+    return;
+  }
+
+  // Check that DstReg matches with next instruction, otherwise the instruction
+  // is not related to stack address manipulation.
+  if (DstReg != MI.getOperand(0).getReg()) {
+    return;
+  }
+
+  // Add the offset in the next instruction to our offset.
+  switch (Opcode) {
+  case AVR::SUBIWRdK:
+    Offset += -MI.getOperand(2).getImm();
+    break;
+  case AVR::ADIWRdK:
+    Offset += MI.getOperand(2).getImm();
+    break;
+  }
+
+  // Finally remove the instruction.
+  MI.eraseFromParent();
+}
+
+void AVRRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II,
+                                          int SPAdj, unsigned FIOperandNum,
+                                          RegScavenger *RS) const {
+  assert(SPAdj == 0 && "Unexpected SPAdj value");
+
+  MachineInstr &MI = *II;
+  DebugLoc dl = MI.getDebugLoc();
+  MachineBasicBlock &MBB = *MI.getParent();
+  const MachineFunction &MF = *MBB.getParent();
+  const AVRTargetMachine &TM = (const AVRTargetMachine &)MF.getTarget();
+  const TargetInstrInfo &TII = *TM.getSubtargetImpl()->getInstrInfo();
+  const MachineFrameInfo *MFI = MF.getFrameInfo();
+  const TargetFrameLowering *TFI = TM.getSubtargetImpl()->getFrameLowering();
+  int FrameIndex = MI.getOperand(FIOperandNum).getIndex();
+  int Offset = MFI->getObjectOffset(FrameIndex);
+
+  // Add one to the offset because SP points to an empty slot.
+  Offset += MFI->getStackSize() - TFI->getOffsetOfLocalArea() + 1;
+  // Fold incoming offset.
+  Offset += MI.getOperand(FIOperandNum + 1).getImm();
+
+  // This is actually "load effective address" of the stack slot
+  // instruction. We have only two-address instructions, thus we need to
+  // expand it into move + add.
+  if (MI.getOpcode() == AVR::FRMIDX) {
+    MI.setDesc(TII.get(AVR::MOVWRdRr));
+    MI.getOperand(FIOperandNum).ChangeToRegister(AVR::R29R28, false);
+
+    assert(Offset > 0 && "Invalid offset");
+
+    // We need to materialize the offset via an add instruction.
+    unsigned Opcode;
+    unsigned DstReg = MI.getOperand(0).getReg();
+    assert(DstReg != AVR::R29R28 && "Dest reg cannot be the frame pointer");
+
+    // Generally, to load a frame address two add instructions are emitted that
+    // could get folded into a single one:
+    //  movw    r31:r30, r29:r28
+    //  adiw    r31:r30, 29
+    //  adiw    r31:r30, 16
+    // to:
+    //  movw    r31:r30, r29:r28
+    //  adiw    r31:r30, 45
+    foldFrameOffset(*std::next(II), Offset, DstReg);
+
+    // Select the best opcode based on DstReg and the offset size.
+    switch (DstReg) {
+    case AVR::R25R24:
+    case AVR::R27R26:
+    case AVR::R31R30: {
+      if (isUInt<6>(Offset)) {
+        Opcode = AVR::ADIWRdK;
+        break;
+      }
+      // Fallthrough
+    }
+    default: {
+      // This opcode will get expanded into a pair of subi/sbci.
+      Opcode = AVR::SUBIWRdK;
+      Offset = -Offset;
+      break;
+    }
+    }
+
+    MachineInstr *New = BuildMI(MBB, std::next(II), dl, TII.get(Opcode), DstReg)
+                            .addReg(DstReg, RegState::Kill)
+                            .addImm(Offset);
+    New->getOperand(3).setIsDead();
+
+    return;
+  }
+
+  // If the offset is too big we have to adjust and restore the frame pointer
+  // to materialize a valid load/store with displacement.
+  //:TODO: consider using only one adiw/sbiw chain for more than one frame index
+  if (Offset >= 63) {
+    unsigned AddOpc = AVR::ADIWRdK, SubOpc = AVR::SBIWRdK;
+    int AddOffset = Offset - 63 + 1;
+
+    // For huge offsets where adiw/sbiw cannot be used use a pair of subi/sbci.
+    if ((Offset - 63 + 1) > 63) {
+      AddOpc = AVR::SUBIWRdK;
+      SubOpc = AVR::SUBIWRdK;
+      AddOffset = -AddOffset;
+    }
+
+    // It is possible that the spiller places this frame instruction in between
+    // a compare and branch, invalidating the contents of SREG set by the
+    // compare instruction because of the add/sub pairs. Conservatively save and
+    // restore SREG before and after each add/sub pair.
+    BuildMI(MBB, II, dl, TII.get(AVR::INRdA), AVR::R0).addImm(0x3f);
+
+    MachineInstr *New = BuildMI(MBB, II, dl, TII.get(AddOpc), AVR::R29R28)
+                            .addReg(AVR::R29R28, RegState::Kill)
+                            .addImm(AddOffset);
+    New->getOperand(3).setIsDead();
+
+    // Restore SREG.
+    BuildMI(MBB, std::next(II), dl, TII.get(AVR::OUTARr))
+        .addImm(0x3f)
+        .addReg(AVR::R0, RegState::Kill);
+
+    // No need to set SREG as dead here otherwise if the next instruction is a
+    // cond branch it will be using a dead register.
+    New = BuildMI(MBB, std::next(II), dl, TII.get(SubOpc), AVR::R29R28)
+              .addReg(AVR::R29R28, RegState::Kill)
+              .addImm(Offset - 63 + 1);
+
+    Offset = 62;
+  }
+
+  MI.getOperand(FIOperandNum).ChangeToRegister(AVR::R29R28, false);
+  assert(isUInt<6>(Offset) && "Offset is out of range");
+  MI.getOperand(FIOperandNum + 1).ChangeToImmediate(Offset);
+}
+
+unsigned AVRRegisterInfo::getFrameRegister(const MachineFunction &MF) const {
+  const TargetFrameLowering *TFI = MF.getSubtarget().getFrameLowering();
+  if (TFI->hasFP(MF)) {
+    // The Y pointer register
+    return AVR::R28;
+  }
+
+  return AVR::SP;
+}
+
+const TargetRegisterClass *
+AVRRegisterInfo::getPointerRegClass(const MachineFunction &MF,
+                                    unsigned Kind) const {
+  // FIXME: Currently we're using avr-gcc as reference, so we restrict
+  // ptrs to Y and Z regs. Though avr-gcc has buggy implementation
+  // of memory constraint, so we can fix it and bit avr-gcc here ;-)
+  return &AVR::PTRDISPREGSRegClass;
+}
+
+} // end of namespace llvm