PostOrderIterator.h [plain text]
#ifndef LLVM_ADT_POSTORDERITERATOR_H
#define LLVM_ADT_POSTORDERITERATOR_H
#include "llvm/ADT/GraphTraits.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/iterator_range.h"
#include <set>
#include <vector>
namespace llvm {
template<class SetType, bool External>
class po_iterator_storage {
SetType Visited;
public:
template<typename NodeType>
bool insertEdge(NodeType *From, NodeType *To) {
return Visited.insert(To).second;
}
template<typename NodeType>
void finishPostorder(NodeType *BB) {}
};
template<class SetType>
class po_iterator_storage<SetType, true> {
SetType &Visited;
public:
po_iterator_storage(SetType &VSet) : Visited(VSet) {}
po_iterator_storage(const po_iterator_storage &S) : Visited(S.Visited) {}
template <class NodeType> bool insertEdge(NodeType *From, NodeType *To) {
return Visited.insert(To).second;
}
template<class NodeType>
void finishPostorder(NodeType *BB) {}
};
template<class GraphT,
class SetType = llvm::SmallPtrSet<typename GraphTraits<GraphT>::NodeType*, 8>,
bool ExtStorage = false,
class GT = GraphTraits<GraphT> >
class po_iterator : public std::iterator<std::forward_iterator_tag,
typename GT::NodeType, ptrdiff_t>,
public po_iterator_storage<SetType, ExtStorage> {
typedef std::iterator<std::forward_iterator_tag,
typename GT::NodeType, ptrdiff_t> super;
typedef typename GT::NodeType NodeType;
typedef typename GT::ChildIteratorType ChildItTy;
std::vector<std::pair<NodeType *, ChildItTy> > VisitStack;
void traverseChild() {
while (VisitStack.back().second != GT::child_end(VisitStack.back().first)) {
NodeType *BB = *VisitStack.back().second++;
if (this->insertEdge(VisitStack.back().first, BB)) {
VisitStack.push_back(std::make_pair(BB, GT::child_begin(BB)));
}
}
}
po_iterator(NodeType *BB) {
this->insertEdge((NodeType*)nullptr, BB);
VisitStack.push_back(std::make_pair(BB, GT::child_begin(BB)));
traverseChild();
}
po_iterator() {}
po_iterator(NodeType *BB, SetType &S)
: po_iterator_storage<SetType, ExtStorage>(S) {
if (this->insertEdge((NodeType*)nullptr, BB)) {
VisitStack.push_back(std::make_pair(BB, GT::child_begin(BB)));
traverseChild();
}
}
po_iterator(SetType &S)
: po_iterator_storage<SetType, ExtStorage>(S) {
} public:
typedef typename super::pointer pointer;
static po_iterator begin(GraphT G) {
return po_iterator(GT::getEntryNode(G));
}
static po_iterator end(GraphT G) { return po_iterator(); }
static po_iterator begin(GraphT G, SetType &S) {
return po_iterator(GT::getEntryNode(G), S);
}
static po_iterator end(GraphT G, SetType &S) { return po_iterator(S); }
bool operator==(const po_iterator &x) const {
return VisitStack == x.VisitStack;
}
bool operator!=(const po_iterator &x) const { return !(*this == x); }
pointer operator*() const { return VisitStack.back().first; }
NodeType *operator->() const { return **this; }
po_iterator &operator++() { this->finishPostorder(VisitStack.back().first);
VisitStack.pop_back();
if (!VisitStack.empty())
traverseChild();
return *this;
}
po_iterator operator++(int) { po_iterator tmp = *this;
++*this;
return tmp;
}
};
template <class T>
po_iterator<T> po_begin(const T &G) { return po_iterator<T>::begin(G); }
template <class T>
po_iterator<T> po_end (const T &G) { return po_iterator<T>::end(G); }
template <class T> iterator_range<po_iterator<T>> post_order(const T &G) {
return make_range(po_begin(G), po_end(G));
}
template<class T, class SetType=std::set<typename GraphTraits<T>::NodeType*> >
struct po_ext_iterator : public po_iterator<T, SetType, true> {
po_ext_iterator(const po_iterator<T, SetType, true> &V) :
po_iterator<T, SetType, true>(V) {}
};
template<class T, class SetType>
po_ext_iterator<T, SetType> po_ext_begin(T G, SetType &S) {
return po_ext_iterator<T, SetType>::begin(G, S);
}
template<class T, class SetType>
po_ext_iterator<T, SetType> po_ext_end(T G, SetType &S) {
return po_ext_iterator<T, SetType>::end(G, S);
}
template <class T, class SetType>
iterator_range<po_ext_iterator<T, SetType>> post_order_ext(const T &G, SetType &S) {
return make_range(po_ext_begin(G, S), po_ext_end(G, S));
}
template <class T,
class SetType = std::set<typename GraphTraits<T>::NodeType*>,
bool External = false>
struct ipo_iterator : public po_iterator<Inverse<T>, SetType, External > {
ipo_iterator(const po_iterator<Inverse<T>, SetType, External> &V) :
po_iterator<Inverse<T>, SetType, External> (V) {}
};
template <class T>
ipo_iterator<T> ipo_begin(const T &G) {
return ipo_iterator<T>::begin(G);
}
template <class T>
ipo_iterator<T> ipo_end(const T &G){
return ipo_iterator<T>::end(G);
}
template <class T>
iterator_range<ipo_iterator<T>> inverse_post_order(const T &G) {
return make_range(ipo_begin(G), ipo_end(G));
}
template <class T,
class SetType = std::set<typename GraphTraits<T>::NodeType*> >
struct ipo_ext_iterator : public ipo_iterator<T, SetType, true> {
ipo_ext_iterator(const ipo_iterator<T, SetType, true> &V) :
ipo_iterator<T, SetType, true>(V) {}
ipo_ext_iterator(const po_iterator<Inverse<T>, SetType, true> &V) :
ipo_iterator<T, SetType, true>(V) {}
};
template <class T, class SetType>
ipo_ext_iterator<T, SetType> ipo_ext_begin(const T &G, SetType &S) {
return ipo_ext_iterator<T, SetType>::begin(G, S);
}
template <class T, class SetType>
ipo_ext_iterator<T, SetType> ipo_ext_end(const T &G, SetType &S) {
return ipo_ext_iterator<T, SetType>::end(G, S);
}
template <class T, class SetType>
iterator_range<ipo_ext_iterator<T, SetType>>
inverse_post_order_ext(const T &G, SetType &S) {
return make_range(ipo_ext_begin(G, S), ipo_ext_end(G, S));
}
template<class GraphT, class GT = GraphTraits<GraphT> >
class ReversePostOrderTraversal {
typedef typename GT::NodeType NodeType;
std::vector<NodeType*> Blocks; void Initialize(NodeType *BB) {
std::copy(po_begin(BB), po_end(BB), std::back_inserter(Blocks));
}
public:
typedef typename std::vector<NodeType*>::reverse_iterator rpo_iterator;
ReversePostOrderTraversal(GraphT G) { Initialize(GT::getEntryNode(G)); }
rpo_iterator begin() { return Blocks.rbegin(); }
rpo_iterator end() { return Blocks.rend(); }
};
}
#endif