C++ Register::getKind方法代码示例

TR::Register *IA32LinkageUtils::pushFloatArg(
      TR::Node *child,
      TR::CodeGenerator *cg)
   {
   TR::Register *pushRegister;
   if (child->getRegister() == NULL)
      {
      if (child->getOpCodeValue() == TR::fconst)
         {
         int32_t value = child->getFloatBits();
         TR_X86OpCodes pushOp;
         if (value >= -128 && value <= 127)
            {
            pushOp = PUSHImms;
            }
         else
            {
            pushOp = PUSHImm4;
            }
         generateImmInstruction(pushOp, child, value, cg);
         cg->decReferenceCount(child);
         return NULL;
         }
      else if (child->getReferenceCount() == 1)
         {
         if (child->getOpCode().isLoad())
            {
            TR::MemoryReference  *tempMR = generateX86MemoryReference(child, cg);
            generateMemInstruction(PUSHMem, child, tempMR, cg);
            tempMR->decNodeReferenceCounts(cg);
            cg->decReferenceCount(child);
            return NULL;
            }
      else if (child->getOpCodeValue() == TR::ibits2f)
         {
         pushRegister = pushIntegerWordArg(child->getFirstChild(), cg);
         cg->decReferenceCount(child);
         return pushRegister;
         }
      }
   }

   pushRegister = cg->evaluate(child);
   TR::RealRegister *espReal = cg->machine()->getRealRegister(TR::RealRegister::esp);
   generateRegImmInstruction(SUB4RegImms, child, espReal, 4, cg);

   if (cg->useSSEForSinglePrecision() && pushRegister->getKind() == TR_FPR)
      generateMemRegInstruction(MOVSSMemReg, child, generateX86MemoryReference(espReal, 0, cg), pushRegister, cg);
   else
      generateFPMemRegInstruction(FSTMemReg, child, generateX86MemoryReference(espReal, 0, cg), pushRegister, cg);

   cg->decReferenceCount(child);
   return pushRegister;
   }

void
TR_S390BinaryAnalyser::genericAnalyser(TR::Node * root,
                                       TR::InstOpCode::Mnemonic regToRegOpCode,
                                       TR::InstOpCode::Mnemonic memToRegOpCode,
                                       TR::InstOpCode::Mnemonic copyOpCode)
   {
   TR::Node * firstChild;
   TR::Node * secondChild;
   firstChild = root->getFirstChild();
   secondChild = root->getSecondChild();
   TR::Register * firstRegister = firstChild->getRegister();
   TR::Register * secondRegister = secondChild->getRegister();
   TR::Compilation *comp = TR::comp();

   TR::SymbolReference * firstReference = firstChild->getOpCode().hasSymbolReference() ? firstChild->getSymbolReference() : NULL;
   TR::SymbolReference * secondReference = secondChild->getOpCode().hasSymbolReference() ? secondChild->getSymbolReference() : NULL;

   setInputs(firstChild, firstRegister, secondChild, secondRegister,
             false, false, comp,
             (cg()->isAddressOfStaticSymRefWithLockedReg(firstReference) ||
              cg()->isAddressOfPrivateStaticSymRefWithLockedReg(firstReference)),
             (cg()->isAddressOfStaticSymRefWithLockedReg(secondReference) ||
              cg()->isAddressOfPrivateStaticSymRefWithLockedReg(secondReference)));

   /*
    * Check if SH or CH can be used to evaluate this integer subtract/compare node.
    * The second operand of SH/CH is a 16-bit number from memory. And using
    * these directly can save a load instruction.
    */
   bool is16BitMemory2Operand = false;
   if (secondChild->getOpCodeValue() == TR::s2i &&
       secondChild->getFirstChild()->getOpCodeValue() == TR::sloadi &&
       secondChild->isSingleRefUnevaluated() &&
       secondChild->getFirstChild()->isSingleRefUnevaluated())
      {
      bool supported = true;

      if (memToRegOpCode == TR::InstOpCode::S)
         {
         memToRegOpCode = TR::InstOpCode::SH;
         }
      else if (memToRegOpCode == TR::InstOpCode::C)
         {
         memToRegOpCode = TR::InstOpCode::CH;
         }
      else
         {
         supported = false;
         }

      if (supported)
         {
         setMem2();
         is16BitMemory2Operand = true;
         }
      }

   if (getEvalChild1())
      {
      firstRegister = cg()->evaluate(firstChild);
      }

   if (getEvalChild2())
      {
      secondRegister = cg()->evaluate(secondChild);
      }

   remapInputs(firstChild, firstRegister, secondChild, secondRegister);

   if (getCopyReg1())
      {
      TR::Register * thirdReg;
      bool done = false;

      if (firstRegister->getKind() == TR_GPR64)
         {
         thirdReg = cg()->allocate64bitRegister();
         }
      else if (firstRegister->getKind() == TR_VRF)
         {
         TR_ASSERT(false,"VRF: genericAnalyser unimplemented");
         }
      else if (firstRegister->getKind() != TR_FPR && firstRegister->getKind() != TR_VRF)
         {
         thirdReg = cg()->allocateRegister();
         }
      else
         {
         thirdReg = cg()->allocateRegister(TR_FPR);
         }

      if (cg()->getS390ProcessorInfo()->supportsArch(TR_S390ProcessorInfo::TR_z196))
         {
         if (getBinaryReg3Reg2() || secondRegister != NULL)
            {
            if (regToRegOpCode == TR::InstOpCode::SR)
               {
               generateRRRInstruction(cg(), TR::InstOpCode::SRK, root, thirdReg, firstRegister, secondRegister);
               done = true;
               }
//.........这里部分代码省略.........

rcount_t
OMR::CodeGenerator::decReferenceCount(TR::Node * node)
   {
   TR::Register *reg = node->getRegister();

   // restricted registers go dead when ref count==2 because
   // their ref count was inced in prepareNodeForInstructionSelection
   if ((node->getReferenceCount() == 1) &&
       reg && self()->getLiveRegisters(reg->getKind()))
       {
      TR_ASSERT(reg->isLive() ||
                (diagnostic("\n*** Error: Register %s for node "
                             "[%s] died prematurely\n",
                             reg->getRegisterName(self()->comp()),
                             node->getName(self()->comp()->getDebug())),
                 0),
             "Node %s register should be live",self()->getDebug()->getName(node));

      TR_LiveRegisterInfo *liveRegister = reg->getLiveRegisterInfo();
      TR::Register *pair = reg->getRegisterPair();
      if (pair)
         {
         pair->getHighOrder()->getLiveRegisterInfo()->decNodeCount();
         pair->getLowOrder()->getLiveRegisterInfo()->decNodeCount();
         }

      if (liveRegister && liveRegister->decNodeCount() == 0)
         {
         // The register is now dead
         //
         self()->getLiveRegisters(reg->getKind())->registerIsDead(reg);
         }
      }

#ifdef J9_PROJECT_SPECIFIC
#if defined(TR_TARGET_S390)
   if (reg && reg->getOpaquePseudoRegister())
      {
      TR_OpaquePseudoRegister *pseudoReg = reg->getOpaquePseudoRegister();
      TR_StorageReference *storageReference = pseudoReg->getStorageReference();
      TR_ASSERT(storageReference,"the pseudoReg should have a non-null storage reference\n");
      storageReference->decrementTemporaryReferenceCount();
      if (node->getReferenceCount() == 1)
         {
         storageReference->decOwningRegisterCount();
         if (self()->traceBCDCodeGen())
            traceMsg(self()->comp(),"\tdecrement owningRegisterCount %d->%d on ref #%d (%s) for reg %s as %s (%p) refCount == 1 (going to 0)\n",
               storageReference->getOwningRegisterCount()+1,
               storageReference->getOwningRegisterCount(),
               storageReference->getReferenceNumber(),
               self()->getDebug()->getName(storageReference->getSymbol()),
               self()->getDebug()->getName(reg),
               node->getOpCode().getName(),
               node);
         }
      }
   else if (node->getOpCode().hasSymbolReference() && node->getSymbolReference() && node->getSymbolReference()->isTempVariableSizeSymRef())
      {
      TR_ASSERT(false,"tempMemSlots should only be attached to pseudoRegisters and not node %p\n",node);
      }
#endif
#endif

   rcount_t count = node->decReferenceCount();
   if (self()->comp()->getOptions()->getTraceCGOption(TR_TraceCGEvaluation))
      {
      self()->getDebug()->printNodeEvaluation(node, "-- ", reg);
      }
   return count;
   }

void TR_PPCRegisterDependencyGroup::assignRegisters(TR::Instruction   *currentInstruction,
                                                    TR_RegisterKinds  kindToBeAssigned,
                                                    uint32_t          numberOfRegisters,
                                                    TR::CodeGenerator *cg)
   {
   // *this    swipeable for debugging purposes
   TR::Machine *machine = cg->machine();
   TR::Register   *virtReg;
   TR::RealRegister::RegNum dependentRegNum;
   TR::RealRegister *dependentRealReg, *assignedRegister, *realReg;
   int i, j;
   TR::Compilation *comp = cg->comp();

   int num_gprs = 0;
   int num_fprs = 0;
   int num_vrfs = 0;

   // Use to do lookups using real register numbers
   TR_PPCRegisterDependencyMap map(_dependencies, numberOfRegisters);

   if (!comp->getOption(TR_DisableOOL))
      {
      for (i = 0; i< numberOfRegisters; i++)
         {
         virtReg = _dependencies[i].getRegister();
         dependentRegNum = _dependencies[i].getRealRegister();
         if (dependentRegNum == TR::RealRegister::SpilledReg)
            {
            TR_ASSERT(virtReg->getBackingStorage(),"should have a backing store if dependentRegNum == spillRegIndex()\n");
            if (virtReg->getAssignedRealRegister())
               {
               // this happens when the register was first spilled in main line path then was reverse spilled
               // and assigned to a real register in OOL path. We protected the backing store when doing
               // the reverse spill so we could re-spill to the same slot now
               traceMsg (comp,"\nOOL: Found register spilled in main line and re-assigned inside OOL");
               TR::Node *currentNode = currentInstruction->getNode();
               TR::RealRegister *assignedReg    = toRealRegister(virtReg->getAssignedRegister());
               TR::MemoryReference *tempMR = new (cg->trHeapMemory()) TR::MemoryReference(currentNode, (TR::SymbolReference*)virtReg->getBackingStorage()->getSymbolReference(), sizeof(uintptr_t), cg);
               TR::InstOpCode::Mnemonic opCode;
               TR_RegisterKinds rk = virtReg->getKind();
               switch (rk)
                  {
                  case TR_GPR:
                     opCode =TR::InstOpCode::Op_load;
                     break;
                  case TR_FPR:
                     opCode = virtReg->isSinglePrecision() ? TR::InstOpCode::lfs : TR::InstOpCode::lfd;
                     break;
                  default:
                     TR_ASSERT(0, "\nRegister kind not supported in OOL spill\n");
                     break;
                  }

               TR::Instruction *inst = generateTrg1MemInstruction(cg, opCode, currentNode, assignedReg, tempMR, currentInstruction);

               assignedReg->setAssignedRegister(NULL);
               virtReg->setAssignedRegister(NULL);
               assignedReg->setState(TR::RealRegister::Free);
               if (comp->getDebug())
                  cg->traceRegisterAssignment("Generate reload of virt %s due to spillRegIndex dep at inst %p\n",comp->getDebug()->getName(virtReg),currentInstruction);
               cg->traceRAInstruction(inst);
               }

            if (!(std::find(cg->getSpilledRegisterList()->begin(), cg->getSpilledRegisterList()->end(), virtReg) != cg->getSpilledRegisterList()->end()))
               cg->getSpilledRegisterList()->push_front(virtReg);
            }
         // we also need to free up all locked backing storage if we are exiting the OOL during backwards RA assignment
         else if (currentInstruction->isLabel() && virtReg->getAssignedRealRegister())
            {
            TR::PPCLabelInstruction *labelInstr = (TR::PPCLabelInstruction *)currentInstruction;
            TR_BackingStore * location = virtReg->getBackingStorage();
            TR_RegisterKinds rk = virtReg->getKind();
            int32_t dataSize;
            if (labelInstr->getLabelSymbol()->isStartOfColdInstructionStream() && location)
               {
               traceMsg (comp,"\nOOL: Releasing backing storage (%p)\n", location);
               if (rk == TR_GPR)
                  dataSize = TR::Compiler->om.sizeofReferenceAddress();
               else
                  dataSize = 8;
               location->setMaxSpillDepth(0);
               cg->freeSpill(location,dataSize,0);
               virtReg->setBackingStorage(NULL);
               }
            }
         }
      }

   for (i = 0; i < numberOfRegisters; i++)
      {
      map.addDependency(_dependencies[i], i);

      virtReg = _dependencies[i].getRegister();
      dependentRegNum = _dependencies[i].getRealRegister();

      if (dependentRegNum != TR::RealRegister::SpilledReg)
         {
         if (virtReg->getKind() == TR_GPR)
            num_gprs++;
         else if (virtReg->getKind() == TR_FPR)
//.........这里部分代码省略.........

static void assignContendedRegisters(TR::Instruction              *currentInstruction,
                                     TR::RegisterDependency    *dep,
                                     TR_PPCRegisterDependencyMap& map,
                                     bool                         depsBlocked,
                                     TR::CodeGenerator            *cg)
   {
   // *this    swipeable for debugging purposes
   TR::Machine *machine = cg->machine();

   dep = findDependencyChainHead(dep, map);


   TR::Register *virtReg = dep->getRegister();
   TR::RealRegister::RegNum targetRegNum = dep->getRealRegister();
   TR::RealRegister *targetReg = machine->getPPCRealRegister(targetRegNum);
   TR::RealRegister *assignedReg = virtReg->getAssignedRealRegister() ?
      toRealRegister(virtReg->getAssignedRealRegister()) :  NULL;


   // Chain of length 1
   if (!assignedReg || !map.getDependencyWithTarget(assignedReg->getRegisterNumber()))
      {
      machine->coerceRegisterAssignment(currentInstruction, virtReg, targetRegNum);
      virtReg->block();
      return;
      }
   // Chain of length 2, handled here instead of below to get 3*xor exchange on GPRs
   if (map.getDependencyWithTarget(assignedReg->getRegisterNumber()) == map.getDependencyWithAssigned(targetRegNum))
      {
      TR::Register *targetVirtReg = targetReg->getAssignedRegister();
      machine->coerceRegisterAssignment(currentInstruction, virtReg, targetRegNum);
      virtReg->block();
      targetVirtReg->block();
      return;
      }

   // Grab a spare reg in order to free the target of the first dep
   // At this point the first dep's target could be blocked, assigned, or NoReg
   // If it's blocked or assigned we allocate a spare and assign the target's virtual to it
   // If it's NoReg, the spare reg will be used as the first dep's actual target
   TR::RealRegister *spareReg = machine->findBestFreeRegister(currentInstruction, virtReg->getKind(),
                                                                targetRegNum == TR::RealRegister::NoReg ? dep->getExcludeGPR0() : false, false,
                                                                targetRegNum == TR::RealRegister::NoReg ? virtReg : targetReg->getAssignedRegister());
   bool                haveFreeSpare = spareReg != NULL;
   if (!spareReg)
      {
      // If the regs in this dep group are not blocked we need to make sure we don't spill a reg that's in the middle of the chain
      if (!depsBlocked)
         {
         if (targetRegNum == TR::RealRegister::NoReg)
            spareReg = machine->freeBestRegister(currentInstruction,
                                                 map.getDependencyWithTarget(assignedReg->getRegisterNumber())->getRegister(),
                                                 assignedReg, false);
         else
            spareReg = machine->freeBestRegister(currentInstruction, virtReg, targetReg, false);
         }
      else
         {
         if (targetRegNum == TR::RealRegister::NoReg)
            spareReg = machine->freeBestRegister(currentInstruction, virtReg, NULL, dep->getExcludeGPR0());
         else
            spareReg = machine->freeBestRegister(currentInstruction, targetReg->getAssignedRegister(), NULL, false);
         }
      }

   if (targetRegNum != TR::RealRegister::NoReg && spareReg != targetReg)
      {
      machine->coerceRegisterAssignment(currentInstruction, targetReg->getAssignedRegister(), spareReg->getRegisterNumber());
      }

   TR_ASSERT(targetRegNum == TR::RealRegister::NoReg ||
          targetReg->getState() == TR::RealRegister::Free, "Expecting free target register");

   if (depsBlocked || targetRegNum != TR::RealRegister::NoReg || haveFreeSpare)
      {

      machine->coerceRegisterAssignment(currentInstruction, virtReg,
                                        targetRegNum == TR::RealRegister::NoReg ?
                                        spareReg->getRegisterNumber() : targetRegNum);
      virtReg->block();
      }

   dep = map.getDependencyWithTarget(assignedReg->getRegisterNumber());
   while (dep)
      {
      virtReg = dep->getRegister();
      targetRegNum = dep->getRealRegister();
      targetReg = machine->getPPCRealRegister(targetRegNum);
      assignedReg = virtReg->getAssignedRealRegister() ?
         toRealRegister(virtReg->getAssignedRealRegister()) : NULL;

      TR_ASSERT(targetReg->getState() == TR::RealRegister::Free || targetReg == spareReg,
             "Expecting free target register or target to have been filled to free spare register");

      machine->coerceRegisterAssignment(currentInstruction, virtReg, targetRegNum);
      virtReg->block();
      dep = assignedReg ?
         map.getDependencyWithTarget(assignedReg->getRegisterNumber()) : NULL;
      }

//.........这里部分代码省略.........

OMR::Power::RegisterDependencyConditions::RegisterDependencyConditions(
                                       TR::CodeGenerator *cg,
                                       TR::Node          *node,
                                       uint32_t          extranum,
                                       TR::Instruction  **cursorPtr)
   {
   List<TR::Register>  regList(cg->trMemory());
   TR::Instruction    *iCursor = (cursorPtr==NULL)?NULL:*cursorPtr;
   int32_t totalNum = node->getNumChildren() + extranum;
   int32_t i;


   cg->comp()->incVisitCount();

   int32_t numLongs = 0;
   //
   // Pre-compute how many longs are global register candidates
   //
   for (i = 0; i < node->getNumChildren(); ++i)
      {
      TR::Node     *child = node->getChild(i);
      TR::Register *reg   = child->getRegister();

      if (reg!=NULL /* && reg->getKind()==TR_GPR */)
	 {
	 if (child->getHighGlobalRegisterNumber() > -1)
	    numLongs++;
	 }
      }

   totalNum = totalNum + numLongs;

   _preConditions = new (totalNum, cg->trMemory()) TR_PPCRegisterDependencyGroup;
   _postConditions = new (totalNum, cg->trMemory()) TR_PPCRegisterDependencyGroup;
   _numPreConditions = totalNum;
   _addCursorForPre = 0;
   _numPostConditions = totalNum;
   _addCursorForPost = 0;

   // First, handle dependencies that match current association
   for (i=0; i<node->getNumChildren(); i++)
      {
      TR::Node *child = node->getChild(i);
      TR::Register *reg = child->getRegister();
      TR::Register *highReg = NULL;
      TR::RealRegister::RegNum regNum = (TR::RealRegister::RegNum)cg->getGlobalRegister(child->getGlobalRegisterNumber());

      TR::RealRegister::RegNum highRegNum;

      if (child->getHighGlobalRegisterNumber() > -1)
         {
         highRegNum = (TR::RealRegister::RegNum)cg->getGlobalRegister(child->getHighGlobalRegisterNumber());

         TR::RegisterPair *regPair = reg->getRegisterPair();
         TR_ASSERT(regPair, "assertion failure");
	 highReg = regPair->getHighOrder();
	 reg = regPair->getLowOrder();

         if (highReg->getAssociation() != highRegNum ||
             reg->getAssociation() != regNum)
            continue;
         }
      else if (reg->getAssociation() != regNum)
         continue;

      TR_ASSERT(!regList.find(reg) && (!highReg || !regList.find(highReg)), "Should not happen\n");

      addPreCondition(reg, regNum);
      addPostCondition(reg, regNum);
      regList.add(reg);

      if (highReg)
	 {
	 addPreCondition(highReg, highRegNum);
	 addPostCondition(highReg, highRegNum);
         regList.add(highReg);
	 }
      }


   // Second pass to handle dependencies for which association does not exist
   // or does not match
   for (i=0; i<node->getNumChildren(); i++)
      {
      TR::Node *child = node->getChild(i);
      TR::Register *reg = child->getRegister();
      TR::Register *highReg = NULL;
      TR::Register *copyReg = NULL;
      TR::Register *highCopyReg = NULL;
      TR::RealRegister::RegNum regNum = (TR::RealRegister::RegNum)cg->getGlobalRegister(child->getGlobalRegisterNumber());


      TR::RealRegister::RegNum highRegNum;

      if (child->getHighGlobalRegisterNumber() > -1)
         {
         highRegNum = (TR::RealRegister::RegNum)cg->getGlobalRegister(child->getHighGlobalRegisterNumber());
         TR::RegisterPair *regPair = reg->getRegisterPair();
         TR_ASSERT(regPair, "assertion failure");
	 highReg = regPair->getHighOrder();
//.........这里部分代码省略.........

void TR_ARMRegisterDependencyGroup::assignRegisters(TR::Instruction  *currentInstruction,
                                                    TR_RegisterKinds kindToBeAssigned,
                                                    uint32_t         numberOfRegisters,
                                                    TR::CodeGenerator *cg)
   {
   TR::Compilation *comp = cg->comp();
   TR::Machine *machine = cg->machine();
   TR::Register  *virtReg;
   TR::RealRegister::RegNum dependentRegNum;
   TR::RealRegister *dependentRealReg, *assignedRegister;
   uint32_t i, j;
   bool changed;

   if (!comp->getOption(TR_DisableOOL))
      {
      for (i = 0; i< numberOfRegisters; i++)
         {
         virtReg = dependencies[i].getRegister();
         dependentRegNum = dependencies[i].getRealRegister();
         if (dependentRegNum == TR::RealRegister::SpilledReg)
            {
            TR_ASSERT(virtReg->getBackingStorage(),"should have a backing store if dependentRegNum == spillRegIndex()\n");
            if (virtReg->getAssignedRealRegister())
               {
               // this happens when the register was first spilled in main line path then was reverse spilled
               // and assigned to a real register in OOL path. We protected the backing store when doing
               // the reverse spill so we could re-spill to the same slot now
               traceMsg (comp,"\nOOL: Found register spilled in main line and re-assigned inside OOL");
               TR::Node *currentNode = currentInstruction->getNode();
               TR::RealRegister *assignedReg    = toRealRegister(virtReg->getAssignedRegister());
               TR::MemoryReference *tempMR = new (cg->trHeapMemory()) TR::MemoryReference(currentNode, (TR::SymbolReference*)virtReg->getBackingStorage()->getSymbolReference(), sizeof(uintptr_t), cg);
               TR_ARMOpCodes opCode;
               TR_RegisterKinds rk = virtReg->getKind();
               switch (rk)
                  {
                  case TR_GPR:
                     opCode = ARMOp_ldr;
                     break;
                  case TR_FPR:
                     opCode = virtReg->isSinglePrecision() ? ARMOp_ldfs : ARMOp_ldfd;
                     break;
                  default:
                     TR_ASSERT(0, "\nRegister kind not supported in OOL spill\n");
                     break;
                  }

               TR::Instruction *inst = generateTrg1MemInstruction(cg, opCode, currentNode, assignedReg, tempMR, currentInstruction);

               assignedReg->setAssignedRegister(NULL);
               virtReg->setAssignedRegister(NULL);
               assignedReg->setState(TR::RealRegister::Free);

               if (comp->getDebug())
                  cg->traceRegisterAssignment("Generate reload of virt %s due to spillRegIndex dep at inst %p\n", cg->comp()->getDebug()->getName(virtReg),currentInstruction);
               cg->traceRAInstruction(inst);
               }
            if (!(std::find(cg->getSpilledRegisterList()->begin(), cg->getSpilledRegisterList()->end(), virtReg) != cg->getSpilledRegisterList()->end()))
               cg->getSpilledRegisterList()->push_front(virtReg);
            }
         // we also need to free up all locked backing storage if we are exiting the OOL during backwards RA assignment
         else if (currentInstruction->isLabel() && virtReg->getAssignedRealRegister())
            {
            TR::ARMLabelInstruction *labelInstr = (TR::ARMLabelInstruction *)currentInstruction;
            TR_BackingStore *location = virtReg->getBackingStorage();
            TR_RegisterKinds rk = virtReg->getKind();
            int32_t dataSize;
            if (labelInstr->getLabelSymbol()->isStartOfColdInstructionStream() && location)
               {
               traceMsg (comp,"\nOOL: Releasing backing storage (%p)\n", location);
               if (rk == TR_GPR)
                  dataSize = TR::Compiler->om.sizeofReferenceAddress();
               else
                  dataSize = 8;
               location->setMaxSpillDepth(0);
               cg->freeSpill(location,dataSize,0);
               virtReg->setBackingStorage(NULL);
               }
            }
         }
      }
   for (i = 0; i < numberOfRegisters; i++)
      {
      virtReg = dependencies[i].getRegister();

      if (virtReg->getAssignedRealRegister()!=NULL)
         {
         if (dependencies[i].getRealRegister() == TR::RealRegister::NoReg)
            {
            virtReg->block();
            }
         else
            {
            dependentRegNum = toRealRegister(virtReg->getAssignedRealRegister())->getRegisterNumber();
            for (j=0; j<numberOfRegisters; j++)
               {
               if (dependentRegNum == dependencies[j].getRealRegister())
                  {
                  virtReg->block();
                  break;
                  }
//.........这里部分代码省略.........