llvm-6502/include/llvm/ADT/MapVector.h
Douglas Gregor 8161d81239 Add count() method to MapVector
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165559 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-09 23:02:47 +00:00

91 lines
2.3 KiB
C++

//===- llvm/ADT/MapVector.h - Map with deterministic value order *- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements a map that provides insertion order iteration. The
// interface is purposefully minimal. The key is assumed to be cheap to copy
// and 2 copies are kept, one for indexing in a DenseMap, one for iteration in
// a std::vector.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_ADT_MAPVECTOR_H
#define LLVM_ADT_MAPVECTOR_H
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/DenseMap.h"
#include <vector>
namespace llvm {
/// This class implements a map that also provides access to all stored values
/// in a deterministic order. The values are kept in a std::vector and the
/// mapping is done with DenseMap from Keys to indexes in that vector.
template<typename KeyT, typename ValueT,
typename MapType = llvm::DenseMap<KeyT, unsigned>,
typename VectorType = std::vector<std::pair<KeyT, ValueT> > >
class MapVector {
typedef typename VectorType::size_type SizeType;
MapType Map;
VectorType Vector;
public:
typedef typename VectorType::iterator iterator;
typedef typename VectorType::const_iterator const_iterator;
SizeType size() const {
return Vector.size();
}
iterator begin() {
return Vector.begin();
}
const_iterator begin() const {
return Vector.begin();
}
iterator end() {
return Vector.end();
}
const_iterator end() const {
return Vector.end();
}
bool empty() const {
return Vector.empty();
}
void clear() {
Map.clear();
Vector.clear();
}
ValueT &operator[](const KeyT &Key) {
std::pair<KeyT, unsigned> Pair = std::make_pair(Key, 0);
std::pair<typename MapType::iterator, bool> Result = Map.insert(Pair);
unsigned &I = Result.first->second;
if (Result.second) {
Vector.push_back(std::make_pair(Key, ValueT()));
I = Vector.size() - 1;
}
return Vector[I].second;
}
unsigned count(const KeyT &Key) const {
typename MapType::const_iterator Pos = Map.find(Key);
return Pos == Map.end()? 0 : 1;
}
};
}
#endif