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diff --git a/contrib/llvm/lib/Target/PowerPC/PPCHazardRecognizers.cpp b/contrib/llvm/lib/Target/PowerPC/PPCHazardRecognizers.cpp
new file mode 100644
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+++ b/contrib/llvm/lib/Target/PowerPC/PPCHazardRecognizers.cpp
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+//===-- PPCHazardRecognizers.cpp - PowerPC Hazard Recognizer Impls --------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements hazard recognizers for scheduling on PowerPC processors.
+//
+//===----------------------------------------------------------------------===//
+
+#include "PPCHazardRecognizers.h"
+#include "PPC.h"
+#include "PPCInstrInfo.h"
+#include "PPCTargetMachine.h"
+#include "llvm/CodeGen/ScheduleDAG.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/raw_ostream.h"
+using namespace llvm;
+
+#define DEBUG_TYPE "pre-RA-sched"
+
+bool PPCDispatchGroupSBHazardRecognizer::isLoadAfterStore(SUnit *SU) {
+  // FIXME: Move this.
+  if (isBCTRAfterSet(SU))
+    return true;
+
+  const MCInstrDesc *MCID = DAG->getInstrDesc(SU);
+  if (!MCID)
+    return false;
+
+  if (!MCID->mayLoad())
+    return false;
+
+  // SU is a load; for any predecessors in this dispatch group, that are stores,
+  // and with which we have an ordering dependency, return true.
+  for (unsigned i = 0, ie = (unsigned) SU->Preds.size(); i != ie; ++i) {
+    const MCInstrDesc *PredMCID = DAG->getInstrDesc(SU->Preds[i].getSUnit());
+    if (!PredMCID || !PredMCID->mayStore())
+      continue;
+
+    if (!SU->Preds[i].isNormalMemory() && !SU->Preds[i].isBarrier())
+      continue;
+
+    for (unsigned j = 0, je = CurGroup.size(); j != je; ++j)
+      if (SU->Preds[i].getSUnit() == CurGroup[j])
+        return true;
+  }
+
+  return false; 
+}
+
+bool PPCDispatchGroupSBHazardRecognizer::isBCTRAfterSet(SUnit *SU) {
+  const MCInstrDesc *MCID = DAG->getInstrDesc(SU);
+  if (!MCID)
+    return false;
+
+  if (!MCID->isBranch())
+    return false;
+
+  // SU is a branch; for any predecessors in this dispatch group, with which we
+  // have a data dependence and set the counter register, return true.
+  for (unsigned i = 0, ie = (unsigned) SU->Preds.size(); i != ie; ++i) {
+    const MCInstrDesc *PredMCID = DAG->getInstrDesc(SU->Preds[i].getSUnit());
+    if (!PredMCID || PredMCID->getSchedClass() != PPC::Sched::IIC_SprMTSPR)
+      continue;
+
+    if (SU->Preds[i].isCtrl())
+      continue;
+
+    for (unsigned j = 0, je = CurGroup.size(); j != je; ++j)
+      if (SU->Preds[i].getSUnit() == CurGroup[j])
+        return true;
+  }
+
+  return false; 
+}
+
+// FIXME: Remove this when we don't need this:
+namespace llvm { namespace PPC { extern int getNonRecordFormOpcode(uint16_t); } }
+
+// FIXME: A lot of code in PPCDispatchGroupSBHazardRecognizer is P7 specific.
+
+bool PPCDispatchGroupSBHazardRecognizer::mustComeFirst(const MCInstrDesc *MCID,
+                                                       unsigned &NSlots) {
+  // FIXME: Indirectly, this information is contained in the itinerary, and
+  // we should derive it from there instead of separately specifying it
+  // here.
+  unsigned IIC = MCID->getSchedClass();
+  switch (IIC) {
+  default:
+    NSlots = 1;
+    break;
+  case PPC::Sched::IIC_IntDivW:
+  case PPC::Sched::IIC_IntDivD:
+  case PPC::Sched::IIC_LdStLoadUpd:
+  case PPC::Sched::IIC_LdStLDU:
+  case PPC::Sched::IIC_LdStLFDU:
+  case PPC::Sched::IIC_LdStLFDUX:
+  case PPC::Sched::IIC_LdStLHA:
+  case PPC::Sched::IIC_LdStLHAU:
+  case PPC::Sched::IIC_LdStLWA:
+  case PPC::Sched::IIC_LdStSTDU:
+  case PPC::Sched::IIC_LdStSTFDU:
+    NSlots = 2;
+    break;
+  case PPC::Sched::IIC_LdStLoadUpdX:
+  case PPC::Sched::IIC_LdStLDUX:
+  case PPC::Sched::IIC_LdStLHAUX:
+  case PPC::Sched::IIC_LdStLWARX:
+  case PPC::Sched::IIC_LdStLDARX:
+  case PPC::Sched::IIC_LdStSTDUX:
+  case PPC::Sched::IIC_LdStSTDCX:
+  case PPC::Sched::IIC_LdStSTWCX:
+  case PPC::Sched::IIC_BrMCRX: // mtcr
+  // FIXME: Add sync/isync (here and in the itinerary).
+    NSlots = 4;
+    break;
+  }
+
+  // FIXME: record-form instructions need a different itinerary class.
+  if (NSlots == 1 && PPC::getNonRecordFormOpcode(MCID->getOpcode()) != -1)
+    NSlots = 2;
+
+  switch (IIC) {
+  default:
+    // All multi-slot instructions must come first.
+    return NSlots > 1;
+  case PPC::Sched::IIC_BrCR: // cr logicals
+  case PPC::Sched::IIC_SprMFCR:
+  case PPC::Sched::IIC_SprMFCRF:
+  case PPC::Sched::IIC_SprMTSPR:
+    return true;
+  }
+}
+
+ScheduleHazardRecognizer::HazardType
+PPCDispatchGroupSBHazardRecognizer::getHazardType(SUnit *SU, int Stalls) {
+  if (Stalls == 0 && isLoadAfterStore(SU))
+    return NoopHazard;
+
+  return ScoreboardHazardRecognizer::getHazardType(SU, Stalls);
+}
+
+bool PPCDispatchGroupSBHazardRecognizer::ShouldPreferAnother(SUnit *SU) {
+  const MCInstrDesc *MCID = DAG->getInstrDesc(SU);
+  unsigned NSlots;
+  if (MCID && mustComeFirst(MCID, NSlots) && CurSlots)
+    return true;
+
+  return ScoreboardHazardRecognizer::ShouldPreferAnother(SU);
+}
+
+unsigned PPCDispatchGroupSBHazardRecognizer::PreEmitNoops(SUnit *SU) {
+  // We only need to fill out a maximum of 5 slots here: The 6th slot could
+  // only be a second branch, and otherwise the next instruction will start a
+  // new group.
+  if (isLoadAfterStore(SU) && CurSlots < 6) {
+    unsigned Directive =
+        DAG->MF.getSubtarget<PPCSubtarget>().getDarwinDirective();
+    // If we're using a special group-terminating nop, then we need only one.
+    if (Directive == PPC::DIR_PWR6 || Directive == PPC::DIR_PWR7 ||
+        Directive == PPC::DIR_PWR8 )
+      return 1;
+
+    return 5 - CurSlots;
+  }
+
+  return ScoreboardHazardRecognizer::PreEmitNoops(SU);
+}
+
+void PPCDispatchGroupSBHazardRecognizer::EmitInstruction(SUnit *SU) {
+  const MCInstrDesc *MCID = DAG->getInstrDesc(SU);
+  if (MCID) {
+    if (CurSlots == 5 || (MCID->isBranch() && CurBranches == 1)) {
+      CurGroup.clear();
+      CurSlots = CurBranches = 0;
+    } else {
+      DEBUG(dbgs() << "**** Adding to dispatch group: SU(" <<
+                      SU->NodeNum << "): ");
+      DEBUG(DAG->dumpNode(SU));
+
+      unsigned NSlots;
+      bool MustBeFirst = mustComeFirst(MCID, NSlots);
+
+      // If this instruction must come first, but does not, then it starts a
+      // new group.
+      if (MustBeFirst && CurSlots) {
+        CurSlots = CurBranches = 0;
+        CurGroup.clear();
+      }
+
+      CurSlots += NSlots;
+      CurGroup.push_back(SU);
+
+      if (MCID->isBranch())
+        ++CurBranches;
+    }
+  }
+
+  return ScoreboardHazardRecognizer::EmitInstruction(SU);
+}
+
+void PPCDispatchGroupSBHazardRecognizer::AdvanceCycle() {
+  return ScoreboardHazardRecognizer::AdvanceCycle();
+}
+
+void PPCDispatchGroupSBHazardRecognizer::RecedeCycle() {
+  llvm_unreachable("Bottom-up scheduling not supported");
+}
+
+void PPCDispatchGroupSBHazardRecognizer::Reset() {
+  CurGroup.clear();
+  CurSlots = CurBranches = 0;
+  return ScoreboardHazardRecognizer::Reset();
+}
+
+void PPCDispatchGroupSBHazardRecognizer::EmitNoop() {
+  unsigned Directive =
+      DAG->MF.getSubtarget<PPCSubtarget>().getDarwinDirective();
+  // If the group has now filled all of its slots, or if we're using a special
+  // group-terminating nop, the group is complete.
+  if (Directive == PPC::DIR_PWR6 || Directive == PPC::DIR_PWR7 ||
+      Directive == PPC::DIR_PWR8 || CurSlots == 6)  {
+    CurGroup.clear();
+    CurSlots = CurBranches = 0;
+  } else {
+    CurGroup.push_back(nullptr);
+    ++CurSlots;
+  }
+}
+
+//===----------------------------------------------------------------------===//
+// PowerPC 970 Hazard Recognizer
+//
+// This models the dispatch group formation of the PPC970 processor.  Dispatch
+// groups are bundles of up to five instructions that can contain various mixes
+// of instructions.  The PPC970 can dispatch a peak of 4 non-branch and one
+// branch instruction per-cycle.
+//
+// There are a number of restrictions to dispatch group formation: some
+// instructions can only be issued in the first slot of a dispatch group, & some
+// instructions fill an entire dispatch group.  Additionally, only branches can
+// issue in the 5th (last) slot.
+//
+// Finally, there are a number of "structural" hazards on the PPC970.  These
+// conditions cause large performance penalties due to misprediction, recovery,
+// and replay logic that has to happen.  These cases include setting a CTR and
+// branching through it in the same dispatch group, and storing to an address,
+// then loading from the same address within a dispatch group.  To avoid these
+// conditions, we insert no-op instructions when appropriate.
+//
+// FIXME: This is missing some significant cases:
+//   1. Modeling of microcoded instructions.
+//   2. Handling of serialized operations.
+//   3. Handling of the esoteric cases in "Resource-based Instruction Grouping".
+//
+
+PPCHazardRecognizer970::PPCHazardRecognizer970(const ScheduleDAG &DAG)
+    : DAG(DAG) {
+  EndDispatchGroup();
+}
+
+void PPCHazardRecognizer970::EndDispatchGroup() {
+  DEBUG(errs() << "=== Start of dispatch group\n");
+  NumIssued = 0;
+
+  // Structural hazard info.
+  HasCTRSet = false;
+  NumStores = 0;
+}
+
+
+PPCII::PPC970_Unit
+PPCHazardRecognizer970::GetInstrType(unsigned Opcode,
+                                     bool &isFirst, bool &isSingle,
+                                     bool &isCracked,
+                                     bool &isLoad, bool &isStore) {
+  const MCInstrDesc &MCID = DAG.TII->get(Opcode);
+
+  isLoad  = MCID.mayLoad();
+  isStore = MCID.mayStore();
+
+  uint64_t TSFlags = MCID.TSFlags;
+
+  isFirst   = TSFlags & PPCII::PPC970_First;
+  isSingle  = TSFlags & PPCII::PPC970_Single;
+  isCracked = TSFlags & PPCII::PPC970_Cracked;
+  return (PPCII::PPC970_Unit)(TSFlags & PPCII::PPC970_Mask);
+}
+
+/// isLoadOfStoredAddress - If we have a load from the previously stored pointer
+/// as indicated by StorePtr1/StorePtr2/StoreSize, return true.
+bool PPCHazardRecognizer970::
+isLoadOfStoredAddress(uint64_t LoadSize, int64_t LoadOffset,
+  const Value *LoadValue) const {
+  for (unsigned i = 0, e = NumStores; i != e; ++i) {
+    // Handle exact and commuted addresses.
+    if (LoadValue == StoreValue[i] && LoadOffset == StoreOffset[i])
+      return true;
+
+    // Okay, we don't have an exact match, if this is an indexed offset, see if
+    // we have overlap (which happens during fp->int conversion for example).
+    if (StoreValue[i] == LoadValue) {
+      // Okay the base pointers match, so we have [c1+r] vs [c2+r].  Check
+      // to see if the load and store actually overlap.
+      if (StoreOffset[i] < LoadOffset) {
+        if (int64_t(StoreOffset[i]+StoreSize[i]) > LoadOffset) return true;
+      } else {
+        if (int64_t(LoadOffset+LoadSize) > StoreOffset[i]) return true;
+      }
+    }
+  }
+  return false;
+}
+
+/// getHazardType - We return hazard for any non-branch instruction that would
+/// terminate the dispatch group.  We turn NoopHazard for any
+/// instructions that wouldn't terminate the dispatch group that would cause a
+/// pipeline flush.
+ScheduleHazardRecognizer::HazardType PPCHazardRecognizer970::
+getHazardType(SUnit *SU, int Stalls) {
+  assert(Stalls == 0 && "PPC hazards don't support scoreboard lookahead");
+
+  MachineInstr *MI = SU->getInstr();
+
+  if (MI->isDebugValue())
+    return NoHazard;
+
+  unsigned Opcode = MI->getOpcode();
+  bool isFirst, isSingle, isCracked, isLoad, isStore;
+  PPCII::PPC970_Unit InstrType =
+    GetInstrType(Opcode, isFirst, isSingle, isCracked,
+                 isLoad, isStore);
+  if (InstrType == PPCII::PPC970_Pseudo) return NoHazard;
+
+  // We can only issue a PPC970_First/PPC970_Single instruction (such as
+  // crand/mtspr/etc) if this is the first cycle of the dispatch group.
+  if (NumIssued != 0 && (isFirst || isSingle))
+    return Hazard;
+
+  // If this instruction is cracked into two ops by the decoder, we know that
+  // it is not a branch and that it cannot issue if 3 other instructions are
+  // already in the dispatch group.
+  if (isCracked && NumIssued > 2)
+    return Hazard;
+
+  switch (InstrType) {
+  default: llvm_unreachable("Unknown instruction type!");
+  case PPCII::PPC970_FXU:
+  case PPCII::PPC970_LSU:
+  case PPCII::PPC970_FPU:
+  case PPCII::PPC970_VALU:
+  case PPCII::PPC970_VPERM:
+    // We can only issue a branch as the last instruction in a group.
+    if (NumIssued == 4) return Hazard;
+    break;
+  case PPCII::PPC970_CRU:
+    // We can only issue a CR instruction in the first two slots.
+    if (NumIssued >= 2) return Hazard;
+    break;
+  case PPCII::PPC970_BRU:
+    break;
+  }
+
+  // Do not allow MTCTR and BCTRL to be in the same dispatch group.
+  if (HasCTRSet && Opcode == PPC::BCTRL)
+    return NoopHazard;
+
+  // If this is a load following a store, make sure it's not to the same or
+  // overlapping address.
+  if (isLoad && NumStores && !MI->memoperands_empty()) {
+    MachineMemOperand *MO = *MI->memoperands_begin();
+    if (isLoadOfStoredAddress(MO->getSize(),
+                              MO->getOffset(), MO->getValue()))
+      return NoopHazard;
+  }
+
+  return NoHazard;
+}
+
+void PPCHazardRecognizer970::EmitInstruction(SUnit *SU) {
+  MachineInstr *MI = SU->getInstr();
+
+  if (MI->isDebugValue())
+    return;
+
+  unsigned Opcode = MI->getOpcode();
+  bool isFirst, isSingle, isCracked, isLoad, isStore;
+  PPCII::PPC970_Unit InstrType =
+    GetInstrType(Opcode, isFirst, isSingle, isCracked,
+                 isLoad, isStore);
+  if (InstrType == PPCII::PPC970_Pseudo) return;
+
+  // Update structural hazard information.
+  if (Opcode == PPC::MTCTR || Opcode == PPC::MTCTR8) HasCTRSet = true;
+
+  // Track the address stored to.
+  if (isStore && NumStores < 4 && !MI->memoperands_empty()) {
+    MachineMemOperand *MO = *MI->memoperands_begin();
+    StoreSize[NumStores] = MO->getSize();
+    StoreOffset[NumStores] = MO->getOffset();
+    StoreValue[NumStores] = MO->getValue();
+    ++NumStores;
+  }
+
+  if (InstrType == PPCII::PPC970_BRU || isSingle)
+    NumIssued = 4;  // Terminate a d-group.
+  ++NumIssued;
+
+  // If this instruction is cracked into two ops by the decoder, remember that
+  // we issued two pieces.
+  if (isCracked)
+    ++NumIssued;
+
+  if (NumIssued == 5)
+    EndDispatchGroup();
+}
+
+void PPCHazardRecognizer970::AdvanceCycle() {
+  assert(NumIssued < 5 && "Illegal dispatch group!");
+  ++NumIssued;
+  if (NumIssued == 5)
+    EndDispatchGroup();
+}
+
+void PPCHazardRecognizer970::Reset() {
+  EndDispatchGroup();
+}
+