예제 #1
0
파일: Local.cpp 프로젝트: brills/pfpa
void GraphBuilder::visitIntToPtrInst(IntToPtrInst &I) {
  DSNode *N = createNode();
  if(I.hasOneUse()) {
    if(isa<ICmpInst>(*(I.use_begin()))) {
      NumBoringIntToPtr++;
      return;
    }
  } else {
    N->setIntToPtrMarker();
    N->setUnknownMarker();
  }
  setDestTo(I, N); 
}
예제 #2
0
파일: Local.cpp 프로젝트: brills/pfpa
///
/// getValueDest - Return the DSNode that the actual value points to.
///
DSNodeHandle GraphBuilder::getValueDest(Value* V) {
  if (isa<Constant>(V) && cast<Constant>(V)->isNullValue()) 
    return 0;  // Null doesn't point to anything, don't add to ScalarMap!

  DSNodeHandle &NH = G.getNodeForValue(V);
  if (!NH.isNull())
    return NH;     // Already have a node?  Just return it...

  // Otherwise we need to create a new node to point to.
  // Check first for constant expressions that must be traversed to
  // extract the actual value.
  DSNode* N;
  if (Function * F = dyn_cast<Function > (V)) {
    // Create a new global node for this function.
    N = createNode();
    N->addFunction(F);
    if (F->isDeclaration())
      N->setExternFuncMarker();
  } else if (GlobalValue * GV = dyn_cast<GlobalValue > (V)) {
    // Create a new global node for this global variable.
    N = createNode();
    N->addGlobal(GV);
    if (GV->isDeclaration())
      N->setExternGlobalMarker();
  } else if (Constant *C = dyn_cast<Constant>(V)) {
    if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
      if (CE->isCast()) {
        if (isa<PointerType>(CE->getOperand(0)->getType()))
          NH = getValueDest(CE->getOperand(0));
        else
          NH = createNode()->setUnknownMarker();
      } else if (CE->getOpcode() == Instruction::GetElementPtr) {
        visitGetElementPtrInst(*CE);
        assert(G.hasNodeForValue(CE) && "GEP didn't get processed right?");
        NH = G.getNodeForValue(CE);
      } else {
        // This returns a conservative unknown node for any unhandled ConstExpr
        NH = createNode()->setUnknownMarker();
      }
      if (NH.isNull()) {  // (getelementptr null, X) returns null
        G.eraseNodeForValue(V);
        return 0;
      }
      return NH;
    } else if (isa<UndefValue>(C)) {
      G.eraseNodeForValue(V);
      return 0;
    } else if (isa<GlobalAlias>(C)) {
      // XXX: Need more investigation
      // According to Andrew, DSA is broken on global aliasing, since it does
      // not handle the aliases of parameters correctly. Here is only a quick
      // fix for some special cases.
      NH = getValueDest(cast<GlobalAlias>(C)->getAliasee());
      return NH;
    } else if (isa<BlockAddress>(C)) {
      //
      // FIXME: This may not be quite right; we should probably add a
      // BlockAddress flag to the DSNode instead of using the unknown flag.
      //
      N = createNode();
      N->setUnknownMarker();
    } else {
      errs() << "Unknown constant: " << *C << "\n";
      assert(0 && "Unknown constant type!");
    }
    N = createNode(); // just create a shadow node
  } else {
    // Otherwise just create a shadow node
    N = createNode();
  }

  NH.setTo(N, 0);      // Remember that we are pointing to it...
  return NH;
}