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diff --git a/contrib/llvm/lib/Target/SystemZ/SystemZHazardRecognizer.cpp b/contrib/llvm/lib/Target/SystemZ/SystemZHazardRecognizer.cpp
new file mode 100644
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+++ b/contrib/llvm/lib/Target/SystemZ/SystemZHazardRecognizer.cpp
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+//=-- SystemZHazardRecognizer.h - SystemZ Hazard Recognizer -----*- C++ -*-===//
+//
+//                     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 hazard recognizer for the SystemZ scheduler.
+//
+// This class is used by the SystemZ scheduling strategy to maintain
+// the state during scheduling, and provide cost functions for
+// scheduling candidates. This includes:
+//
+// * Decoder grouping. A decoder group can maximally hold 3 uops, and
+// instructions that always begin a new group should be scheduled when
+// the current decoder group is empty.
+// * Processor resources usage. It is beneficial to balance the use of
+// resources.
+//
+// ===---------------------------------------------------------------------===//
+
+#include "SystemZHazardRecognizer.h"
+#include "llvm/ADT/Statistic.h"
+
+using namespace llvm;
+
+#define DEBUG_TYPE "misched"
+
+// This is the limit of processor resource usage at which the
+// scheduler should try to look for other instructions (not using the
+// critical resource).
+static cl::opt<int> ProcResCostLim("procres-cost-lim", cl::Hidden,
+                                   cl::desc("The OOO window for processor "
+                                            "resources during scheduling."),
+                                   cl::init(8));
+
+SystemZHazardRecognizer::
+SystemZHazardRecognizer(const MachineSchedContext *C) : DAG(nullptr),
+                                                        SchedModel(nullptr) {}
+
+unsigned SystemZHazardRecognizer::
+getNumDecoderSlots(SUnit *SU) const {
+  const MCSchedClassDesc *SC = DAG->getSchedClass(SU);
+  if (!SC->isValid())
+    return 0; // IMPLICIT_DEF / KILL -- will not make impact in output.
+
+  if (SC->BeginGroup) {
+    if (!SC->EndGroup)
+      return 2; // Cracked instruction
+    else
+      return 3; // Expanded/group-alone instruction
+  }
+    
+  return 1; // Normal instruction
+}
+
+unsigned SystemZHazardRecognizer::getCurrCycleIdx() {
+  unsigned Idx = CurrGroupSize;
+  if (GrpCount % 2)
+    Idx += 3;
+  return Idx;
+}
+
+ScheduleHazardRecognizer::HazardType SystemZHazardRecognizer::
+getHazardType(SUnit *m, int Stalls) {
+  return (fitsIntoCurrentGroup(m) ? NoHazard : Hazard);
+}
+
+void SystemZHazardRecognizer::Reset() {
+  CurrGroupSize = 0;
+  clearProcResCounters();
+  GrpCount = 0;
+  LastFPdOpCycleIdx = UINT_MAX;
+  DEBUG(CurGroupDbg = "";);
+}
+
+bool
+SystemZHazardRecognizer::fitsIntoCurrentGroup(SUnit *SU) const {
+  const MCSchedClassDesc *SC = DAG->getSchedClass(SU);
+  if (!SC->isValid())
+    return true;
+
+  // A cracked instruction only fits into schedule if the current
+  // group is empty.
+  if (SC->BeginGroup)
+    return (CurrGroupSize == 0);
+
+  // Since a full group is handled immediately in EmitInstruction(),
+  // SU should fit into current group. NumSlots should be 1 or 0,
+  // since it is not a cracked or expanded instruction.
+  assert ((getNumDecoderSlots(SU) <= 1) && (CurrGroupSize < 3) &&
+          "Expected normal instruction to fit in non-full group!");
+
+  return true;
+}
+
+void SystemZHazardRecognizer::nextGroup(bool DbgOutput) {
+  if (CurrGroupSize > 0) {
+    DEBUG(dumpCurrGroup("Completed decode group"));
+    DEBUG(CurGroupDbg = "";);
+
+    GrpCount++;
+
+    // Reset counter for next group.
+    CurrGroupSize = 0;
+
+    // Decrease counters for execution units by one.
+    for (unsigned i = 0; i < SchedModel->getNumProcResourceKinds(); ++i)
+      if (ProcResourceCounters[i] > 0)
+        ProcResourceCounters[i]--;
+
+    // Clear CriticalResourceIdx if it is now below the threshold.
+    if (CriticalResourceIdx != UINT_MAX &&
+        (ProcResourceCounters[CriticalResourceIdx] <=
+         ProcResCostLim))
+      CriticalResourceIdx = UINT_MAX;
+  }
+
+  DEBUG(if (DbgOutput)
+          dumpProcResourceCounters(););
+}
+
+#ifndef NDEBUG // Debug output
+void SystemZHazardRecognizer::dumpSU(SUnit *SU, raw_ostream &OS) const {
+  OS << "SU(" << SU->NodeNum << "):";
+  OS << SchedModel->getInstrInfo()->getName(SU->getInstr()->getOpcode());
+
+  const MCSchedClassDesc *SC = DAG->getSchedClass(SU);
+  if (!SC->isValid())
+    return;
+  
+  for (TargetSchedModel::ProcResIter
+         PI = SchedModel->getWriteProcResBegin(SC),
+         PE = SchedModel->getWriteProcResEnd(SC); PI != PE; ++PI) {
+    const MCProcResourceDesc &PRD =
+      *SchedModel->getProcResource(PI->ProcResourceIdx);
+    std::string FU(PRD.Name);
+    // trim e.g. Z13_FXaUnit -> FXa
+    FU = FU.substr(FU.find("_") + 1);
+    FU.resize(FU.find("Unit"));
+    OS << "/" << FU;
+
+    if (PI->Cycles > 1)
+      OS << "(" << PI->Cycles << "cyc)";
+  }
+
+  if (SC->NumMicroOps > 1)
+    OS << "/" << SC->NumMicroOps << "uops";
+  if (SC->BeginGroup && SC->EndGroup)
+    OS << "/GroupsAlone";
+  else if (SC->BeginGroup)
+    OS << "/BeginsGroup";
+  else if (SC->EndGroup)
+    OS << "/EndsGroup";
+  if (SU->isUnbuffered)
+    OS << "/Unbuffered";
+}
+
+void SystemZHazardRecognizer::dumpCurrGroup(std::string Msg) const {
+  dbgs() << "+++ " << Msg;
+  dbgs() << ": ";
+
+  if (CurGroupDbg.empty())
+    dbgs() << " <empty>\n";
+  else {
+    dbgs() << "{ " << CurGroupDbg << " }";
+    dbgs() << " (" << CurrGroupSize << " decoder slot"
+           << (CurrGroupSize > 1 ? "s":"")
+           << ")\n";
+  }
+}
+
+void SystemZHazardRecognizer::dumpProcResourceCounters() const {
+  bool any = false;
+
+  for (unsigned i = 0; i < SchedModel->getNumProcResourceKinds(); ++i)
+    if (ProcResourceCounters[i] > 0) {
+      any = true;
+      break;
+    }
+
+  if (!any)
+    return;
+
+  dbgs() << "+++ Resource counters:\n";
+  for (unsigned i = 0; i < SchedModel->getNumProcResourceKinds(); ++i)
+    if (ProcResourceCounters[i] > 0) {
+      dbgs() << "+++ Extra schedule for execution unit "
+             << SchedModel->getProcResource(i)->Name
+             << ": " << ProcResourceCounters[i] << "\n";
+      any = true;
+    }
+}
+#endif //NDEBUG
+
+void SystemZHazardRecognizer::clearProcResCounters() {
+  ProcResourceCounters.assign(SchedModel->getNumProcResourceKinds(), 0);
+  CriticalResourceIdx = UINT_MAX;
+}
+
+// Update state with SU as the next scheduled unit.
+void SystemZHazardRecognizer::
+EmitInstruction(SUnit *SU) {
+  const MCSchedClassDesc *SC = DAG->getSchedClass(SU);
+  DEBUG( dumpCurrGroup("Decode group before emission"););
+
+  // If scheduling an SU that must begin a new decoder group, move on
+  // to next group.
+  if (!fitsIntoCurrentGroup(SU))
+    nextGroup();
+
+  DEBUG( dbgs() << "+++ HazardRecognizer emitting "; dumpSU(SU, dbgs());
+         dbgs() << "\n";
+         raw_string_ostream cgd(CurGroupDbg);
+         if (CurGroupDbg.length())
+           cgd << ", ";
+         dumpSU(SU, cgd););
+
+  // After returning from a call, we don't know much about the state.
+  if (SU->getInstr()->isCall()) {
+    DEBUG (dbgs() << "+++ Clearing state after call.\n";);
+    clearProcResCounters();
+    LastFPdOpCycleIdx = UINT_MAX;
+    CurrGroupSize += getNumDecoderSlots(SU);
+    assert (CurrGroupSize <= 3);
+    nextGroup();
+    return;
+  }
+
+  // Increase counter for execution unit(s).
+  for (TargetSchedModel::ProcResIter
+         PI = SchedModel->getWriteProcResBegin(SC),
+         PE = SchedModel->getWriteProcResEnd(SC); PI != PE; ++PI) {
+    // Don't handle FPd together with the other resources.
+    if (SchedModel->getProcResource(PI->ProcResourceIdx)->BufferSize == 1)
+      continue;
+    int &CurrCounter =
+      ProcResourceCounters[PI->ProcResourceIdx];
+    CurrCounter += PI->Cycles;
+    // Check if this is now the new critical resource.
+    if ((CurrCounter > ProcResCostLim) &&
+        (CriticalResourceIdx == UINT_MAX ||
+         (PI->ProcResourceIdx != CriticalResourceIdx &&
+          CurrCounter >
+          ProcResourceCounters[CriticalResourceIdx]))) {
+      DEBUG( dbgs() << "+++ New critical resource: "
+             << SchedModel->getProcResource(PI->ProcResourceIdx)->Name
+             << "\n";);
+      CriticalResourceIdx = PI->ProcResourceIdx;
+    }
+  }
+
+  // Make note of an instruction that uses a blocking resource (FPd).
+  if (SU->isUnbuffered) {
+    LastFPdOpCycleIdx = getCurrCycleIdx();
+    DEBUG (dbgs() << "+++ Last FPd cycle index: "
+           << LastFPdOpCycleIdx << "\n";);
+  }
+
+  // Insert SU into current group by increasing number of slots used
+  // in current group.
+  CurrGroupSize += getNumDecoderSlots(SU);
+  assert (CurrGroupSize <= 3);
+
+  // Check if current group is now full/ended. If so, move on to next
+  // group to be ready to evaluate more candidates.
+  if (CurrGroupSize == 3 || SC->EndGroup)
+    nextGroup();
+}
+
+int SystemZHazardRecognizer::groupingCost(SUnit *SU) const {
+  const MCSchedClassDesc *SC = DAG->getSchedClass(SU);
+  if (!SC->isValid())
+    return 0;
+  
+  // If SU begins new group, it can either break a current group early
+  // or fit naturally if current group is empty (negative cost).
+  if (SC->BeginGroup) {
+    if (CurrGroupSize)
+      return 3 - CurrGroupSize;
+    return -1;
+  }
+
+  // Similarly, a group-ending SU may either fit well (last in group), or
+  // end the group prematurely.
+  if (SC->EndGroup) {
+    unsigned resultingGroupSize =
+      (CurrGroupSize + getNumDecoderSlots(SU));
+    if (resultingGroupSize < 3)
+      return (3 - resultingGroupSize);
+    return -1;
+  }
+
+  // Most instructions can be placed in any decoder slot.
+  return 0;
+}
+
+bool SystemZHazardRecognizer::isFPdOpPreferred_distance(const SUnit *SU) {
+  assert (SU->isUnbuffered);
+  // If this is the first FPd op, it should be scheduled high.
+  if (LastFPdOpCycleIdx == UINT_MAX)
+    return true;
+  // If this is not the first PFd op, it should go into the other side
+  // of the processor to use the other FPd unit there. This should
+  // generally happen if two FPd ops are placed with 2 other
+  // instructions between them (modulo 6).
+  if (LastFPdOpCycleIdx > getCurrCycleIdx())
+    return ((LastFPdOpCycleIdx - getCurrCycleIdx()) == 3);
+  return ((getCurrCycleIdx() - LastFPdOpCycleIdx) == 3);
+}
+
+int SystemZHazardRecognizer::
+resourcesCost(SUnit *SU) {
+  int Cost = 0;
+
+  const MCSchedClassDesc *SC = DAG->getSchedClass(SU);
+  if (!SC->isValid())
+    return 0;
+
+  // For a FPd op, either return min or max value as indicated by the
+  // distance to any prior FPd op.
+  if (SU->isUnbuffered)
+    Cost = (isFPdOpPreferred_distance(SU) ? INT_MIN : INT_MAX);
+  // For other instructions, give a cost to the use of the critical resource.
+  else if (CriticalResourceIdx != UINT_MAX) {
+    for (TargetSchedModel::ProcResIter
+           PI = SchedModel->getWriteProcResBegin(SC),
+           PE = SchedModel->getWriteProcResEnd(SC); PI != PE; ++PI)
+      if (PI->ProcResourceIdx == CriticalResourceIdx)
+        Cost = PI->Cycles;
+  }
+
+  return Cost;
+}
+