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diff --git a/contrib/llvm/lib/CodeGen/SelectionDAG/ScheduleDAGList.cpp b/contrib/llvm/lib/CodeGen/SelectionDAG/ScheduleDAGList.cpp
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+++ b/contrib/llvm/lib/CodeGen/SelectionDAG/ScheduleDAGList.cpp
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+//===---- ScheduleDAGList.cpp - Implement a list scheduler for isel DAG ---===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This implements a top-down list scheduler, using standard algorithms.
+// The basic approach uses a priority queue of available nodes to schedule.
+// One at a time, nodes are taken from the priority queue (thus in priority
+// order), checked for legality to schedule, and emitted if legal.
+//
+// Nodes may not be legal to schedule either due to structural hazards (e.g.
+// pipeline or resource constraints) or because an input to the instruction has
+// not completed execution.
+//
+//===----------------------------------------------------------------------===//
+
+#define DEBUG_TYPE "pre-RA-sched"
+#include "ScheduleDAGSDNodes.h"
+#include "llvm/CodeGen/LatencyPriorityQueue.h"
+#include "llvm/CodeGen/ScheduleHazardRecognizer.h"
+#include "llvm/CodeGen/SchedulerRegistry.h"
+#include "llvm/CodeGen/SelectionDAGISel.h"
+#include "llvm/Target/TargetRegisterInfo.h"
+#include "llvm/Target/TargetData.h"
+#include "llvm/Target/TargetInstrInfo.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/ADT/Statistic.h"
+#include <climits>
+using namespace llvm;
+
+STATISTIC(NumNoops , "Number of noops inserted");
+STATISTIC(NumStalls, "Number of pipeline stalls");
+
+static RegisterScheduler
+  tdListDAGScheduler("list-td", "Top-down list scheduler",
+                     createTDListDAGScheduler);
+   
+namespace {
+//===----------------------------------------------------------------------===//
+/// ScheduleDAGList - The actual list scheduler implementation.  This supports
+/// top-down scheduling.
+///
+class ScheduleDAGList : public ScheduleDAGSDNodes {
+private:
+  /// AvailableQueue - The priority queue to use for the available SUnits.
+  ///
+  SchedulingPriorityQueue *AvailableQueue;
+  
+  /// PendingQueue - This contains all of the instructions whose operands have
+  /// been issued, but their results are not ready yet (due to the latency of
+  /// the operation).  Once the operands become available, the instruction is
+  /// added to the AvailableQueue.
+  std::vector<SUnit*> PendingQueue;
+
+  /// HazardRec - The hazard recognizer to use.
+  ScheduleHazardRecognizer *HazardRec;
+
+public:
+  ScheduleDAGList(MachineFunction &mf,
+                  SchedulingPriorityQueue *availqueue,
+                  ScheduleHazardRecognizer *HR)
+    : ScheduleDAGSDNodes(mf),
+      AvailableQueue(availqueue), HazardRec(HR) {
+    }
+
+  ~ScheduleDAGList() {
+    delete HazardRec;
+    delete AvailableQueue;
+  }
+
+  void Schedule();
+
+private:
+  void ReleaseSucc(SUnit *SU, const SDep &D);
+  void ReleaseSuccessors(SUnit *SU);
+  void ScheduleNodeTopDown(SUnit *SU, unsigned CurCycle);
+  void ListScheduleTopDown();
+};
+}  // end anonymous namespace
+
+/// Schedule - Schedule the DAG using list scheduling.
+void ScheduleDAGList::Schedule() {
+  DEBUG(dbgs() << "********** List Scheduling **********\n");
+  
+  // Build the scheduling graph.
+  BuildSchedGraph(NULL);
+
+  AvailableQueue->initNodes(SUnits);
+  
+  ListScheduleTopDown();
+  
+  AvailableQueue->releaseState();
+}
+
+//===----------------------------------------------------------------------===//
+//  Top-Down Scheduling
+//===----------------------------------------------------------------------===//
+
+/// ReleaseSucc - Decrement the NumPredsLeft count of a successor. Add it to
+/// the PendingQueue if the count reaches zero. Also update its cycle bound.
+void ScheduleDAGList::ReleaseSucc(SUnit *SU, const SDep &D) {
+  SUnit *SuccSU = D.getSUnit();
+
+#ifndef NDEBUG
+  if (SuccSU->NumPredsLeft == 0) {
+    dbgs() << "*** Scheduling failed! ***\n";
+    SuccSU->dump(this);
+    dbgs() << " has been released too many times!\n";
+    llvm_unreachable(0);
+  }
+#endif
+  --SuccSU->NumPredsLeft;
+
+  SuccSU->setDepthToAtLeast(SU->getDepth() + D.getLatency());
+  
+  // If all the node's predecessors are scheduled, this node is ready
+  // to be scheduled. Ignore the special ExitSU node.
+  if (SuccSU->NumPredsLeft == 0 && SuccSU != &ExitSU)
+    PendingQueue.push_back(SuccSU);
+}
+
+void ScheduleDAGList::ReleaseSuccessors(SUnit *SU) {
+  // Top down: release successors.
+  for (SUnit::succ_iterator I = SU->Succs.begin(), E = SU->Succs.end();
+       I != E; ++I) {
+    assert(!I->isAssignedRegDep() &&
+           "The list-td scheduler doesn't yet support physreg dependencies!");
+
+    ReleaseSucc(SU, *I);
+  }
+}
+
+/// ScheduleNodeTopDown - Add the node to the schedule. Decrement the pending
+/// count of its successors. If a successor pending count is zero, add it to
+/// the Available queue.
+void ScheduleDAGList::ScheduleNodeTopDown(SUnit *SU, unsigned CurCycle) {
+  DEBUG(dbgs() << "*** Scheduling [" << CurCycle << "]: ");
+  DEBUG(SU->dump(this));
+  
+  Sequence.push_back(SU);
+  assert(CurCycle >= SU->getDepth() && "Node scheduled above its depth!");
+  SU->setDepthToAtLeast(CurCycle);
+
+  ReleaseSuccessors(SU);
+  SU->isScheduled = true;
+  AvailableQueue->ScheduledNode(SU);
+}
+
+/// ListScheduleTopDown - The main loop of list scheduling for top-down
+/// schedulers.
+void ScheduleDAGList::ListScheduleTopDown() {
+  unsigned CurCycle = 0;
+
+  // Release any successors of the special Entry node.
+  ReleaseSuccessors(&EntrySU);
+
+  // All leaves to Available queue.
+  for (unsigned i = 0, e = SUnits.size(); i != e; ++i) {
+    // It is available if it has no predecessors.
+    if (SUnits[i].Preds.empty()) {
+      AvailableQueue->push(&SUnits[i]);
+      SUnits[i].isAvailable = true;
+    }
+  }
+  
+  // While Available queue is not empty, grab the node with the highest
+  // priority. If it is not ready put it back.  Schedule the node.
+  std::vector<SUnit*> NotReady;
+  Sequence.reserve(SUnits.size());
+  while (!AvailableQueue->empty() || !PendingQueue.empty()) {
+    // Check to see if any of the pending instructions are ready to issue.  If
+    // so, add them to the available queue.
+    for (unsigned i = 0, e = PendingQueue.size(); i != e; ++i) {
+      if (PendingQueue[i]->getDepth() == CurCycle) {
+        AvailableQueue->push(PendingQueue[i]);
+        PendingQueue[i]->isAvailable = true;
+        PendingQueue[i] = PendingQueue.back();
+        PendingQueue.pop_back();
+        --i; --e;
+      } else {
+        assert(PendingQueue[i]->getDepth() > CurCycle && "Negative latency?");
+      }
+    }
+    
+    // If there are no instructions available, don't try to issue anything, and
+    // don't advance the hazard recognizer.
+    if (AvailableQueue->empty()) {
+      ++CurCycle;
+      continue;
+    }
+
+    SUnit *FoundSUnit = 0;
+    
+    bool HasNoopHazards = false;
+    while (!AvailableQueue->empty()) {
+      SUnit *CurSUnit = AvailableQueue->pop();
+      
+      ScheduleHazardRecognizer::HazardType HT =
+        HazardRec->getHazardType(CurSUnit);
+      if (HT == ScheduleHazardRecognizer::NoHazard) {
+        FoundSUnit = CurSUnit;
+        break;
+      }
+    
+      // Remember if this is a noop hazard.
+      HasNoopHazards |= HT == ScheduleHazardRecognizer::NoopHazard;
+      
+      NotReady.push_back(CurSUnit);
+    }
+    
+    // Add the nodes that aren't ready back onto the available list.
+    if (!NotReady.empty()) {
+      AvailableQueue->push_all(NotReady);
+      NotReady.clear();
+    }
+
+    // If we found a node to schedule, do it now.
+    if (FoundSUnit) {
+      ScheduleNodeTopDown(FoundSUnit, CurCycle);
+      HazardRec->EmitInstruction(FoundSUnit);
+
+      // If this is a pseudo-op node, we don't want to increment the current
+      // cycle.
+      if (FoundSUnit->Latency)  // Don't increment CurCycle for pseudo-ops!
+        ++CurCycle;        
+    } else if (!HasNoopHazards) {
+      // Otherwise, we have a pipeline stall, but no other problem, just advance
+      // the current cycle and try again.
+      DEBUG(dbgs() << "*** Advancing cycle, no work to do\n");
+      HazardRec->AdvanceCycle();
+      ++NumStalls;
+      ++CurCycle;
+    } else {
+      // Otherwise, we have no instructions to issue and we have instructions
+      // that will fault if we don't do this right.  This is the case for
+      // processors without pipeline interlocks and other cases.
+      DEBUG(dbgs() << "*** Emitting noop\n");
+      HazardRec->EmitNoop();
+      Sequence.push_back(0);   // NULL here means noop
+      ++NumNoops;
+      ++CurCycle;
+    }
+  }
+
+#ifndef NDEBUG
+  VerifySchedule(/*isBottomUp=*/false);
+#endif
+}
+
+//===----------------------------------------------------------------------===//
+//                         Public Constructor Functions
+//===----------------------------------------------------------------------===//
+
+/// createTDListDAGScheduler - This creates a top-down list scheduler with a
+/// new hazard recognizer. This scheduler takes ownership of the hazard
+/// recognizer and deletes it when done.
+ScheduleDAGSDNodes *
+llvm::createTDListDAGScheduler(SelectionDAGISel *IS, CodeGenOpt::Level) {
+  return new ScheduleDAGList(*IS->MF,
+                             new LatencyPriorityQueue(),
+                             IS->CreateTargetHazardRecognizer());
+}