C++ Register::block方法代码示例

void TR::ARM64MemSrc1Instruction::assignRegisters(TR_RegisterKinds kindToBeAssigned)
   {
   TR::Machine *machine = cg()->machine();
   TR::MemoryReference *mref = getMemoryReference();
   TR::Register *sourceVirtual = getSource1Register();

   if (getDependencyConditions())
      getDependencyConditions()->assignPostConditionRegisters(this, kindToBeAssigned, cg());

   sourceVirtual->block();
   mref->assignRegisters(this, cg());
   sourceVirtual->unblock();

   mref->blockRegisters();
   TR::RealRegister *assignedRegister = sourceVirtual->getAssignedRealRegister();
   if (assignedRegister == NULL)
      {
      assignedRegister = machine->assignOneRegister(this, sourceVirtual);
      }
   mref->unblockRegisters();

   setSource1Register(assignedRegister);

   if (getDependencyConditions())
      getDependencyConditions()->assignPreConditionRegisters(this->getPrev(), kindToBeAssigned, cg());
   }

//.........这里部分代码省略.........
   int locked_gprs = 0;
   int locked_fprs = 0;
   int locked_vrfs = 0;

   // count up how many registers are locked for each type
   for(i = TR::RealRegister::FirstGPR; i <= TR::RealRegister::LastGPR; i++)
      {
        realReg = machine->getPPCRealRegister((TR::RealRegister::RegNum)i);
        if (realReg->getState() == TR::RealRegister::Locked)
           locked_gprs++;
      }
   for(i = TR::RealRegister::FirstFPR; i <= TR::RealRegister::LastFPR; i++)
      {
        realReg = machine->getPPCRealRegister((TR::RealRegister::RegNum)i);
        if (realReg->getState() == TR::RealRegister::Locked)
           locked_fprs++;
      }
   for(i = TR::RealRegister::FirstVRF; i <= TR::RealRegister::LastVRF; i++)
      {
        realReg = machine->getPPCRealRegister((TR::RealRegister::RegNum)i);
        if (realReg->getState() == TR::RealRegister::Locked)
           locked_vrfs++;
      }
   TR_ASSERT( locked_gprs == machine->getNumberOfLockedRegisters(TR_GPR),"Inconsistent number of locked GPRs");
   TR_ASSERT( locked_fprs == machine->getNumberOfLockedRegisters(TR_FPR),"Inconsistent number of locked FPRs");
   TR_ASSERT( locked_vrfs == machine->getNumberOfLockedRegisters(TR_VRF), "Inconsistent number of locked VRFs");
#endif

   // To handle circular dependencies, we block a real register if (1) it is already assigned to a correct
   // virtual register and (2) if it is assigned to one register in the list but is required by another.
   // However, if all available registers are requested, we do not block in case (2) to avoid all registers
   // being blocked.

   bool block_gprs = true;
   bool block_fprs = true;
   bool block_vrfs = true;

   TR_ASSERT(num_gprs <= (TR::RealRegister::LastGPR - TR::RealRegister::FirstGPR + 1 - machine->getNumberOfLockedRegisters(TR_GPR)), "Too many GPR dependencies, unable to assign" );
   TR_ASSERT(num_fprs <= (TR::RealRegister::LastFPR - TR::RealRegister::FirstFPR + 1 - machine->getNumberOfLockedRegisters(TR_FPR)), "Too many FPR dependencies, unable to assign" );
   TR_ASSERT(num_vrfs <= (TR::RealRegister::LastVRF - TR::RealRegister::FirstVRF + 1 - machine->getNumberOfLockedRegisters(TR_VRF)), "Too many VRF dependencies, unable to assign" );

   if (num_gprs == (TR::RealRegister::LastGPR - TR::RealRegister::FirstGPR + 1 - machine->getNumberOfLockedRegisters(TR_GPR)))
        block_gprs = false;
   if (num_fprs == (TR::RealRegister::LastFPR - TR::RealRegister::FirstFPR + 1 - machine->getNumberOfLockedRegisters(TR_FPR)))
        block_fprs = false;
   if (num_vrfs == (TR::RealRegister::LastVRF - TR::RealRegister::FirstVRF + 1 - machine->getNumberOfLockedRegisters(TR_VRF)))
        block_vrfs = false;

   for (i = 0; i < numberOfRegisters; i++)
      {
      virtReg = _dependencies[i].getRegister();

      if (virtReg->getAssignedRealRegister()!=NULL)
         {
         if (_dependencies[i].getRealRegister() == TR::RealRegister::NoReg)
            {
            virtReg->block();
            }
         else
            {
            TR::RealRegister::RegNum assignedRegNum;
            assignedRegNum = toRealRegister(virtReg->getAssignedRealRegister())->getRegisterNumber();

            // always block if required register and assigned register match;
            // block if assigned register is required by other dependency but only if
            // any spare registers are left to avoid blocking all existing registers

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.........

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.........