Function selectBaseRowsToLoad

bolt/vector/LazyVector.cpp:139–177

Given a SelectivityVector 'rows', updates 'baseRows' selecting the rows in the base vector that should be loaded.

// Given a SelectivityVector 'rows', updates 'baseRows' selecting the rows
// in the base vector that should be loaded.
void selectBaseRowsToLoad(
    const DecodedVector& decoded,
    SelectivityVector& baseRows,
    const SelectivityVector& rows) {
  BOLT_DCHECK(
      decoded.base()->encoding() == VectorEncoding::Simple::ROW ||
      decoded.base()->encoding() == VectorEncoding::Simple::LAZY);

  auto deselectNullsIdentity = [&]() {
    if (decoded.base()->rawNulls()) {
      baseRows.deselectNulls(
          decoded.base()->rawNulls(), rows.begin(), rows.end());
    }
  };

  if (decoded.isIdentityMapping() && rows.isAllSelected()) {
    baseRows.resizeFill(rows.end(), true);
    deselectNullsIdentity();
    return;
  }

  if (decoded.isIdentityMapping()) {
    baseRows.resizeFill(rows.end(), false);
    baseRows.select(rows);
    deselectNullsIdentity();
  } else if (decoded.isConstantMapping()) {
    baseRows.resizeFill(decoded.index(0) + 1, false);
    baseRows.setValid(decoded.index(0), true);
  } else {
    baseRows.resizeFill(decoded.base()->size(), false);
    rows.applyToSelected([&](vector_size_t row) {
      if (!decoded.isNullAt(row)) {
        baseRows.setValid(decoded.index(row), true);
      }
    });
  }

  baseRows.updateBounds();
}
} // namespace

// static