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diff --git a/contrib/llvm/lib/CodeGen/DFAPacketizer.cpp b/contrib/llvm/lib/CodeGen/DFAPacketizer.cpp
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+//=- llvm/CodeGen/DFAPacketizer.cpp - DFA Packetizer for VLIW -*- C++ -*-=====//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+// This class implements a deterministic finite automaton (DFA) based
+// packetizing mechanism for VLIW architectures. It provides APIs to
+// determine whether there exists a legal mapping of instructions to
+// functional unit assignments in a packet. The DFA is auto-generated from
+// the target's Schedule.td file.
+//
+// A DFA consists of 3 major elements: states, inputs, and transitions. For
+// the packetizing mechanism, the input is the set of instruction classes for
+// a target. The state models all possible combinations of functional unit
+// consumption for a given set of instructions in a packet. A transition
+// models the addition of an instruction to a packet. In the DFA constructed
+// by this class, if an instruction can be added to a packet, then a valid
+// transition exists from the corresponding state. Invalid transitions
+// indicate that the instruction cannot be added to the current packet.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/CodeGen/DFAPacketizer.h"
+#include "llvm/CodeGen/MachineInstr.h"
+#include "llvm/CodeGen/MachineInstrBundle.h"
+#include "llvm/CodeGen/ScheduleDAGInstrs.h"
+#include "llvm/MC/MCInstrItineraries.h"
+#include "llvm/Target/TargetInstrInfo.h"
+using namespace llvm;
+
+DFAPacketizer::DFAPacketizer(const InstrItineraryData *I, const int (*SIT)[2],
+                             const unsigned *SET):
+  InstrItins(I), CurrentState(0), DFAStateInputTable(SIT),
+  DFAStateEntryTable(SET) {}
+
+
+//
+// ReadTable - Read the DFA transition table and update CachedTable.
+//
+// Format of the transition tables:
+// DFAStateInputTable[][2] = pairs of <Input, Transition> for all valid
+//                           transitions
+// DFAStateEntryTable[i] = Index of the first entry in DFAStateInputTable
+//                         for the ith state
+//
+void DFAPacketizer::ReadTable(unsigned int state) {
+  unsigned ThisState = DFAStateEntryTable[state];
+  unsigned NextStateInTable = DFAStateEntryTable[state+1];
+  // Early exit in case CachedTable has already contains this
+  // state's transitions.
+  if (CachedTable.count(UnsignPair(state,
+                                   DFAStateInputTable[ThisState][0])))
+    return;
+
+  for (unsigned i = ThisState; i < NextStateInTable; i++)
+    CachedTable[UnsignPair(state, DFAStateInputTable[i][0])] =
+      DFAStateInputTable[i][1];
+}
+
+
+// canReserveResources - Check if the resources occupied by a MCInstrDesc
+// are available in the current state.
+bool DFAPacketizer::canReserveResources(const llvm::MCInstrDesc *MID) {
+  unsigned InsnClass = MID->getSchedClass();
+  const llvm::InstrStage *IS = InstrItins->beginStage(InsnClass);
+  unsigned FuncUnits = IS->getUnits();
+  UnsignPair StateTrans = UnsignPair(CurrentState, FuncUnits);
+  ReadTable(CurrentState);
+  return (CachedTable.count(StateTrans) != 0);
+}
+
+
+// reserveResources - Reserve the resources occupied by a MCInstrDesc and
+// change the current state to reflect that change.
+void DFAPacketizer::reserveResources(const llvm::MCInstrDesc *MID) {
+  unsigned InsnClass = MID->getSchedClass();
+  const llvm::InstrStage *IS = InstrItins->beginStage(InsnClass);
+  unsigned FuncUnits = IS->getUnits();
+  UnsignPair StateTrans = UnsignPair(CurrentState, FuncUnits);
+  ReadTable(CurrentState);
+  assert(CachedTable.count(StateTrans) != 0);
+  CurrentState = CachedTable[StateTrans];
+}
+
+
+// canReserveResources - Check if the resources occupied by a machine
+// instruction are available in the current state.
+bool DFAPacketizer::canReserveResources(llvm::MachineInstr *MI) {
+  const llvm::MCInstrDesc &MID = MI->getDesc();
+  return canReserveResources(&MID);
+}
+
+// reserveResources - Reserve the resources occupied by a machine
+// instruction and change the current state to reflect that change.
+void DFAPacketizer::reserveResources(llvm::MachineInstr *MI) {
+  const llvm::MCInstrDesc &MID = MI->getDesc();
+  reserveResources(&MID);
+}
+
+namespace llvm {
+// DefaultVLIWScheduler - This class extends ScheduleDAGInstrs and overrides
+// Schedule method to build the dependence graph.
+class DefaultVLIWScheduler : public ScheduleDAGInstrs {
+public:
+  DefaultVLIWScheduler(MachineFunction &MF, MachineLoopInfo &MLI,
+                   MachineDominatorTree &MDT, bool IsPostRA);
+  // Schedule - Actual scheduling work.
+  void schedule();
+};
+}
+
+DefaultVLIWScheduler::DefaultVLIWScheduler(
+  MachineFunction &MF, MachineLoopInfo &MLI, MachineDominatorTree &MDT,
+  bool IsPostRA) :
+  ScheduleDAGInstrs(MF, MLI, MDT, IsPostRA) {
+  CanHandleTerminators = true;
+}
+
+void DefaultVLIWScheduler::schedule() {
+  // Build the scheduling graph.
+  buildSchedGraph(0);
+}
+
+// VLIWPacketizerList Ctor
+VLIWPacketizerList::VLIWPacketizerList(
+  MachineFunction &MF, MachineLoopInfo &MLI, MachineDominatorTree &MDT,
+  bool IsPostRA) : TM(MF.getTarget()), MF(MF)  {
+  TII = TM.getInstrInfo();
+  ResourceTracker = TII->CreateTargetScheduleState(&TM, 0);
+  VLIWScheduler = new DefaultVLIWScheduler(MF, MLI, MDT, IsPostRA);
+}
+
+// VLIWPacketizerList Dtor
+VLIWPacketizerList::~VLIWPacketizerList() {
+  if (VLIWScheduler)
+    delete VLIWScheduler;
+
+  if (ResourceTracker)
+    delete ResourceTracker;
+}
+
+// endPacket - End the current packet, bundle packet instructions and reset
+// DFA state.
+void VLIWPacketizerList::endPacket(MachineBasicBlock *MBB,
+                                         MachineInstr *MI) {
+  if (CurrentPacketMIs.size() > 1) {
+    MachineInstr *MIFirst = CurrentPacketMIs.front();
+    finalizeBundle(*MBB, MIFirst, MI);
+  }
+  CurrentPacketMIs.clear();
+  ResourceTracker->clearResources();
+}
+
+// PacketizeMIs - Bundle machine instructions into packets.
+void VLIWPacketizerList::PacketizeMIs(MachineBasicBlock *MBB,
+                                      MachineBasicBlock::iterator BeginItr,
+                                      MachineBasicBlock::iterator EndItr) {
+  assert(VLIWScheduler && "VLIW Scheduler is not initialized!");
+  VLIWScheduler->startBlock(MBB);
+  VLIWScheduler->enterRegion(MBB, BeginItr, EndItr,
+                             std::distance(BeginItr, EndItr));
+  VLIWScheduler->schedule();
+
+  // Generate MI -> SU map.
+  MIToSUnit.clear();
+  for (unsigned i = 0, e = VLIWScheduler->SUnits.size(); i != e; ++i) {
+    SUnit *SU = &VLIWScheduler->SUnits[i];
+    MIToSUnit[SU->getInstr()] = SU;
+  }
+
+  // The main packetizer loop.
+  for (; BeginItr != EndItr; ++BeginItr) {
+    MachineInstr *MI = BeginItr;
+
+    this->initPacketizerState();
+
+    // End the current packet if needed.
+    if (this->isSoloInstruction(MI)) {
+      endPacket(MBB, MI);
+      continue;
+    }
+
+    // Ignore pseudo instructions.
+    if (this->ignorePseudoInstruction(MI, MBB))
+      continue;
+
+    SUnit *SUI = MIToSUnit[MI];
+    assert(SUI && "Missing SUnit Info!");
+
+    // Ask DFA if machine resource is available for MI.
+    bool ResourceAvail = ResourceTracker->canReserveResources(MI);
+    if (ResourceAvail) {
+      // Dependency check for MI with instructions in CurrentPacketMIs.
+      for (std::vector<MachineInstr*>::iterator VI = CurrentPacketMIs.begin(),
+           VE = CurrentPacketMIs.end(); VI != VE; ++VI) {
+        MachineInstr *MJ = *VI;
+        SUnit *SUJ = MIToSUnit[MJ];
+        assert(SUJ && "Missing SUnit Info!");
+
+        // Is it legal to packetize SUI and SUJ together.
+        if (!this->isLegalToPacketizeTogether(SUI, SUJ)) {
+          // Allow packetization if dependency can be pruned.
+          if (!this->isLegalToPruneDependencies(SUI, SUJ)) {
+            // End the packet if dependency cannot be pruned.
+            endPacket(MBB, MI);
+            break;
+          } // !isLegalToPruneDependencies.
+        } // !isLegalToPacketizeTogether.
+      } // For all instructions in CurrentPacketMIs.
+    } else {
+      // End the packet if resource is not available.
+      endPacket(MBB, MI);
+    }
+
+    // Add MI to the current packet.
+    BeginItr = this->addToPacket(MI);
+  } // For all instructions in BB.
+
+  // End any packet left behind.
+  endPacket(MBB, EndItr);
+  VLIWScheduler->exitRegion();
+  VLIWScheduler->finishBlock();
+}