C++ Block::isCold方法代码示例

// Process the structure recursively
//
int32_t
TR_ExpressionsSimplification::perform(TR_Structure * str)
   {
   if (trace())
      traceMsg(comp(), "Analyzing root Structure : %p\n", str);

   TR_RegionStructure *region;

   // Only regions can be simplified
   //
   if (!(region = str->asRegion()))
      return 0;

   TR_RegionStructure::Cursor it(*region);

   for (TR_StructureSubGraphNode *node = it.getCurrent();
        node != 0;
        node = it.getNext())
      {
      // Too strict
      /*
      if ((node->getPredecessors().size() == 1))
         {
         TR::CFGEdge *edge = node->getPredecessors().front();
         TR_StructureSubGraphNode *pred = toStructureSubGraphNode(edge->getFrom());
         TR_BlockStructure *b = pred->getStructure()->asBlock();
         if (b && pred->getSuccessors().size() == 1))
            perform(node->getStructure());
         }
      */
      perform(node->getStructure());
      }

   // debug only
   //
   /*
   if (region->isNaturalLoop() &&
          (region->getParent()  &&
            !region->getParent()->asRegion()->isCanonicalizedLoop()))
      {
      traceMsg(comp(), "Loop not canonicalized %x\n", region);
      }
   */

   TR::Block *entryBlock = region->getEntryBlock();
   if (region->isNaturalLoop() && !entryBlock->isCold() &&
          (region->getParent() /* &&
            region->getParent()->asRegion()->isCanonicalizedLoop() */))
         {
         if (trace())
           traceMsg(comp(), "Found candidate non cold loop %p for expression elimination\n", region);

         findAndSimplifyInvariantLoopExpressions(region);
         }

   return 1;  // Need to specify the cost
   }

TR_GlobalRegisterNumber
OMR::X86::I386::CodeGenerator::pickRegister(
      TR_RegisterCandidate *rc,
      TR::Block **allBlocks,
      TR_BitVector &availableRegisters,
      TR_GlobalRegisterNumber &highRegisterNumber,
      TR_LinkHead<TR_RegisterCandidate> *candidates)
   {
   if (!self()->comp()->getOption(TR_DisableRegisterPressureSimulation))
      {
      if (self()->comp()->getOption(TR_AssignEveryGlobalRegister))
         {
         // This is not really necessary except for testing purposes.
         // Conceptually, the common pickRegister code should be free to make
         // its choices based only on performance considerations, and shouldn't
         // need to worry about correctness.  When SupportsVMThreadGRA is not set,
         // it is incorrect to choose the VMThread register.  Therefore we mask
         // it out here.
         //
         // Having said that, the common code *does* already mask out the
         // VMThread register for convenience, so under normal circumstances,
         // this code is redundant.  It is only necessary when
         // TR_AssignEveryGlobalRegister is set.
         //
         availableRegisters -= *self()->getGlobalRegisters(TR_vmThreadSpill, self()->comp()->getMethodSymbol()->getLinkageConvention());
         }
      return OMR::CodeGenerator::pickRegister(rc, allBlocks, availableRegisters, highRegisterNumber, candidates);
      }

   if ((rc->getSymbol()->getDataType() == TR::Float) ||
       (rc->getSymbol()->getDataType() == TR::Double))
      {
      if (availableRegisters.get(7))
         return 7;
      if (availableRegisters.get(8))
         return 8;
      if (availableRegisters.get(9))
         return 9;
      if (availableRegisters.get(10))
         return 10;
      if (availableRegisters.get(11))
         return 11;
      if (availableRegisters.get(12))
         return 12;

      return -1;
      }


   if (!_assignedGlobalRegisters)
      _assignedGlobalRegisters = new (self()->trStackMemory()) TR_BitVector(self()->comp()->getSymRefCount(), self()->trMemory(), stackAlloc, growable);

   if (availableRegisters.get(5))
      return 5; // esi

   if (availableRegisters.get(2))
      return 2; // ecx

   static char *dontUseEBXasGPR = feGetEnv("dontUseEBXasGPR");
   if (!dontUseEBXasGPR && availableRegisters.get(1))
      return 1;

#ifdef J9_PROJECT_SPECIFIC
   TR::RecognizedMethod rm = self()->comp()->getMethodSymbol()->getRecognizedMethod();
   if (rm == TR::java_util_HashtableHashEnumerator_hasMoreElements)
      {
      if (availableRegisters.get(4))
         return 4; // edi
      if (availableRegisters.get(3))
         return 3; // edx
      }
   else
#endif
      {
      int32_t numExtraRegs = 0;
      int32_t maxRegisterPressure = 0;

      vcount_t visitCount = self()->comp()->incVisitCount();
      TR_BitVectorIterator bvi(rc->getBlocksLiveOnEntry());
      int32_t maxFrequency = 0;
      while (bvi.hasMoreElements())
         {
         int32_t liveBlockNum = bvi.getNextElement();
         TR::Block *block = allBlocks[liveBlockNum];
         if (block->getFrequency() > maxFrequency)
             maxFrequency = block->getFrequency();
         }

      int32_t maxStaticFrequency = 0;
      if (maxFrequency == 0)
         {
         bvi.setBitVector(rc->getBlocksLiveOnEntry());
         while (bvi.hasMoreElements())
            {
            int32_t liveBlockNum = bvi.getNextElement();
            TR::Block *block = allBlocks[liveBlockNum];
            TR_BlockStructure *blockStructure = block->getStructureOf();
            int32_t blockWeight = 1;
            if (blockStructure &&
                !block->isCold())
//.........这里部分代码省略.........