void removeRedundantBlocks(BlockPtr b) {
StatementList& children = b->getChildren();
for (size_t i = 0; i < children.size(); ++i) {
if (REN_DYNAMIC_CAST_PTR(ib, Block, children[i])) {
removeRedundantBlocks(ib);
StatementList sl = ib->getChildren();
children.erase(children.begin() + i);
children.insert(children.begin() + i, sl.begin(), sl.end());
--i;
}
}
}
