C++ DSNode::getSize方法代码示例

//.........这里部分代码省略.........

    // Merge all of the facts for the callee into the facts for the caller.  If
    // this reduces anything in the caller to 'bottom', remove them.
    for (DSGraph::NodeMapTy::iterator MI = CallNodeMap.begin(),
           E = CallNodeMap.end(); MI != E; ++MI) {
      // If we have Lattice facts in the caller for this node in the callee,
      // merge any information from the callee into the caller.

      // If the node is not accessed in the callee at all, don't update.
      if (MI->first->getType() == Type::VoidTy)
        continue;

      // If there are no data-flow facts live in the caller for this node, don't
      // both processing it.
      std::multimap<DSNode*, LatticeValue*>::iterator NLVI =
        NodeLVs.find(MI->second.getNode());
      if (NLVI == NodeLVs.end()) continue;
          
          
      // Iterate over all of the lattice values that have corresponding fields
      // in the callee, merging in information as we go.  Be careful about the
      // fact that the callee may get passed the address of a substructure and
      // other funny games.
      //if (CalleeFacts.count(const_cast<DSNode*>(MI->first)) == 0) {

      DSNode *CalleeNode = const_cast<DSNode*>(MI->first);

      unsigned CalleeNodeOffset = MI->second.getOffset();
      while (NLVI->first == MI->second.getNode()) {
        // Figure out what offset in the callee this field would land.
        unsigned FieldOff = NLVI->second->getFieldOffset()+CalleeNodeOffset;

        // If the field is not within the callee node, ignore it.
        if (FieldOff >= CalleeNode->getSize()) {
          ++NLVI;
          continue;
        }

        // Okay, check to see if we have a lattice value for the field at offset
        // FieldOff in the callee node.
        const LatticeValue *CalleeLV = 0;

        std::multimap<DSNode*, LatticeValue*>::iterator CFI = 
          CalleeFacts.lower_bound(CalleeNode);
        for (; CFI != CalleeFacts.end() && CFI->first == CalleeNode; ++CFI)
          if (CFI->second->getFieldOffset() == FieldOff) {
            CalleeLV = CFI->second;   // Found it!
            break;
          }
        
        // If we don't, the lattice value hit bottom and we should remove the
        // lattice value in the caller.
        if (!CalleeLV) {
          delete NLVI->second;   // The lattice value hit bottom.
          NodeLVs.erase(NLVI++);
          continue;
        }

        // Finally, if we did find a corresponding entry, merge the information
        // into the caller's lattice value and keep going.
        if (NLVI->second->mergeInValue(CalleeLV)) {
          // Okay, merging these two caused the caller value to hit bottom.
          // Remove it.
          delete NLVI->second;   // The lattice value hit bottom.
          NodeLVs.erase(NLVI++);
        }

void
PoolRegisterElimination::removeSingletonRegistrations (const char * name) {
  //
  // Scan through all uses of the registration function and see if it can be
  // safely removed.  If so, schedule it for removal.
  //
  std::vector<CallInst*> toBeRemoved;
  Function * F = intrinsic->getIntrinsic(name).F;

  //
  // Look for and record all registrations that can be deleted.
  //
  for (Value::use_iterator UI=F->use_begin(), UE=F->use_end();
       UI != UE;
       ++UI) {
    //
    // Get the pointer to the registered object.
    //
    CallInst * CI = cast<CallInst>(*UI);
    Value * Ptr = intrinsic->getValuePointer(CI);

    //
    // Lookup the DSNode for the value in the function's DSGraph.
    //
    DSGraph * TDG = dsaPass->getDSGraph(*(CI->getParent()->getParent()));
    DSNodeHandle DSH = TDG->getNodeForValue(Ptr);
    assert ((!(DSH.isNull())) && "No DSNode for Value!\n");

    //
    // If the object being registered is the same size as that found in the
    // DSNode, then we know it's a singleton object.  The run-time doesn't need
    // such objects registered in the splay trees, so we can remove the
    // registration function.
    //
    DSNode * N = DSH.getNode();
    Value * Size = intrinsic->getObjectSize (Ptr->stripPointerCasts());
    if (Size) {
      if (ConstantInt * C = dyn_cast<ConstantInt>(Size)) {
        unsigned long size = C->getZExtValue();
        if (size == N->getSize()) {
          toBeRemoved.push_back(CI);
          continue;
        }
      }
    }
  }

  //
  // Update the statistics.
  //
  if (toBeRemoved.size()) {
    RemovedRegistration += toBeRemoved.size();
    SingletonRegistrations += toBeRemoved.size();
  }

  //
  // Remove the unnecesary registrations.
  //
  std::vector<CallInst*>::iterator it, end;
  for (it = toBeRemoved.begin(), end = toBeRemoved.end(); it != end; ++it) {
    (*it)->eraseFromParent();
  }
}

//.........这里部分代码省略.........
    // even think about it.
    if (!GraphUsesGlobal) continue;

    // Otherwise, compute the full set of dataflow effects of the function.
    std::multimap<DSNode*, LatticeValue*> &FGF = getCalleeFacts(FG);
    //std::cerr << "Computed: " << FG.getFunctionNames() << "\n";

#if 0
    for (std::multimap<DSNode*, LatticeValue*>::iterator I = FGF.begin(),
           E = FGF.end(); I != E; ++I)
      I->second->dump();
#endif
    // Compute the mapping of nodes in the globals graph to the function's
    // graph.  Note that this function graph may not have nodes (or may have
    // fragments of full nodes) in the globals graph, and we don't want this to
    // pessimize the analysis.
    std::multimap<const DSNode*, std::pair<DSNode*,int> > GraphMap;
    DSGraph::NodeMapTy GraphToGGMap;
    FG.computeGToGGMapping(GraphToGGMap);

    // "Invert" the mapping.  We compute the mapping from the start of a global
    // graph node to a place in the graph's node.  Note that not all of the GG
    // node may be present in the graphs node, so there may be a negative offset
    // involved.
    while (!GraphToGGMap.empty()) {
      DSNode *GN = const_cast<DSNode*>(GraphToGGMap.begin()->first);
      DSNodeHandle &GGNH = GraphToGGMap.begin()->second;
      GraphMap.insert(std::make_pair(GGNH.getNode(),
                                     std::make_pair(GN, -GGNH.getOffset())));
      GraphToGGMap.erase(GraphToGGMap.begin());
    }

    // Loop over all of the dataflow facts that we have computed, mapping them
    // to the globals graph.
    for (std::multimap<DSNode*, LatticeValue*>::iterator I = NodeLVs.begin(),
           E = NodeLVs.end(); I != E; ) {
      bool FactHitBottom = false;

      //I->second->dump();

      assert(I->first->getParentGraph() == &DSG);
      assert(I->second->getNode()->getParentGraph() == &DSG);

      // Node is in the GG?
      DSGraph::NodeMapTy::iterator DSGToGGMapI = DSGToGGMap.find(I->first);
      if (DSGToGGMapI != DSGToGGMap.end()) {
        DSNodeHandle &GGNH = DSGToGGMapI->second;
        const DSNode *GGNode = GGNH.getNode();
        unsigned DSGToGGOffset = GGNH.getOffset();

        // See if there is a node in FG that corresponds to this one.  If not,
        // no information will be computed in this scope, as the memory is not
        // accessed.
        std::multimap<const DSNode*, std::pair<DSNode*,int> >::iterator GMI =
          GraphMap.find(GGNode);

        // LatticeValOffset - The offset from the start of the GG Node to the
        // start of the field we are interested in.
        unsigned LatticeValOffset = I->second->getFieldOffset()+DSGToGGOffset;

        // Loop over all of the nodes in FG that correspond to this single node
        // in the GG.
        for (; GMI != GraphMap.end() && GMI->first == GGNode; ++GMI) {
          // Compute the offset to the field in the user graph.
          unsigned FieldOffset = LatticeValOffset - GMI->second.second;

          // If the field is within the amount of memory accessed by this scope,
          // then there must be a corresponding lattice value.
          DSNode *FGNode = GMI->second.first;
          if (FieldOffset < FGNode->getSize()) {
            LatticeValue *CorrespondingLV = 0;

            std::multimap<DSNode*, LatticeValue*>::iterator FGFI =
              FGF.find(FGNode);
            for (; FGFI != FGF.end() && FGFI->first == FGNode; ++FGFI)
              if (FGFI->second->getFieldOffset() == FieldOffset) {
                CorrespondingLV = FGFI->second;
                break;
              }

            // Finally, if either there was no corresponding fact (because it
            // hit bottom in this scope), or if merging the two pieces of
            // information makes it hit bottom, remember this.
            if (CorrespondingLV == 0 ||
                I->second->mergeInValue(CorrespondingLV))
              FactHitBottom = true;
          }
        }
      }

      if (FactHitBottom) {
        delete I->second;
        NodeLVs.erase(I++);
        if (NodeLVs.empty()) return;
      } else {
        ++I;
      }
    }
  }
}