Ejemplo n.º 1
0
void BlockState::mergePredecessorAvailSetAndValue(RLEContext &Ctx) {
  // Clear the state if the basic block has no predecessor.
  if (BB->getPreds().begin() == BB->getPreds().end()) {
    ForwardSetIn.reset();
    ForwardValIn.clear();
    return;
  }

  auto Iter = BB->pred_begin();
  ForwardSetIn = Ctx.getBlockState(*Iter).ForwardSetOut;
  ForwardValIn = Ctx.getBlockState(*Iter).ForwardValOut;
  Iter = std::next(Iter);
  for (auto EndIter = BB->pred_end(); Iter != EndIter; ++Iter) {
    BlockState &OtherState = Ctx.getBlockState(*Iter);
    ForwardSetIn &= OtherState.ForwardSetOut;

    // Merge in the predecessor state.
    for (unsigned i = 0; i < LocationNum; ++i) {
      if (OtherState.ForwardSetOut[i]) {
        // There are multiple values from multiple predecessors, set this as
        // a covering value. We do not need to track the value itself, as we
        // can always go to the predecessors BlockState to find it.
        ForwardValIn[i] = Ctx.getValueBit(LSValue(true));
        continue;
      }
      // If this location does have an available value, then clear it.
      stopTrackingValue(ForwardValIn, i);
      stopTrackingLocation(ForwardSetIn, i);
    }
  }
}
Ejemplo n.º 2
0
void BlockState::mergePredecessorsAvailSetMax(RLEContext &Ctx) {
  if (BB->pred_empty()) {
    ForwardSetMax.reset();
    return;
  }

  auto Iter = BB->pred_begin();
  ForwardSetMax = Ctx.getBlockState(*Iter).ForwardSetMax;
  Iter = std::next(Iter);
  for (auto EndIter = BB->pred_end(); Iter != EndIter; ++Iter) {
    ForwardSetMax &= Ctx.getBlockState(*Iter).ForwardSetMax;
  }
}
Ejemplo n.º 3
0
void BlockState::mergePredecessorAvailSet(RLEContext &Ctx) {
  // Clear the state if the basic block has no predecessor.
  if (BB->getPreds().begin() == BB->getPreds().end()) {
    ForwardSetIn.reset();
    return;
  }

  auto Iter = BB->pred_begin();
  ForwardSetIn = Ctx.getBlockState(*Iter).ForwardSetOut;
  Iter = std::next(Iter);
  for (auto EndIter = BB->pred_end(); Iter != EndIter; ++Iter) {
    ForwardSetIn &= Ctx.getBlockState(*Iter).ForwardSetOut;
  }
}
Ejemplo n.º 4
0
void BlockState::mergePredecessorStates(RLEContext &Ctx, RLEKind Kind) {
  // Clear the state if the basic block has no predecessor.
  if (BB->getPreds().begin() == BB->getPreds().end()) {
    clearLSLocations();
    return;
  }

  // We initialize the state with the first predecessor's state and merge
  // in states of other predecessors.
  bool HasAtLeastOnePred = false;
  // For each predecessor of BB...
  for (auto Pred : BB->getPreds()) {
    BlockState &Other = Ctx.getBlockState(Pred);

    // If we have not had at least one predecessor, initialize BlockState
    // with the state of the initial predecessor.
    // If BB is also a predecessor of itself, we should not initialize.
    if (!HasAtLeastOnePred) {
      if (isComputeAvailSet(Kind)) {
        ForwardSetIn = Other.ForwardSetOut;
      }
      if (isComputeAvailValue(Kind) || isPerformRLE(Kind)) {
        ForwardSetIn = Other.ForwardSetOut;
        ForwardValIn = Other.ForwardValOut;
      }
    } else {
      mergePredecessorState(Ctx, Other, Kind);
    }
    HasAtLeastOnePred = true;
  }
}