llvm-6502/include/llvm/ADT/ImmutableMap.h
Ted Kremenek 33bbed8f2a Added implementation of immutable (functional) maps and sets, as
implemented on top of a functional AVL tree.  The AVL balancing code
is inspired by the OCaml implementation of Map, which also uses a functional
AVL tree.

Documentation is currently limited and cleanups are planned, but this code
compiles and has been tested.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@42813 91177308-0d34-0410-b5e6-96231b3b80d8
2007-10-09 21:38:09 +00:00

164 lines
4.4 KiB
C++

//===--- ImmutableMap.h - Immutable (functional) map interface --*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by Ted Kremenek and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines the ImmutableMap class.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_ADT_IMMAP_H
#define LLVM_ADT_IMMAP_H
#include "llvm/ADT/ImmutableSet.h"
namespace llvm {
/// ImutKeyValueInfo -Traits class used by ImmutableMap. While both the first and
/// second elements in a pair are used to generate profile information,
/// only the first element (the key) is used by isEqual and isLess.
template <typename T, typename S>
struct ImutKeyValueInfo {
typedef const std::pair<T,S> value_type;
typedef const value_type& value_type_ref;
typedef const T key_type;
typedef const T& key_type_ref;
typedef const S data_type;
typedef const S& data_type_ref;
static inline key_type_ref KeyOfValue(value_type_ref V) {
return V.first;
}
static inline bool isEqual(key_type_ref L, key_type_ref R) {
return ImutContainerInfo<T>::isEqual(L,R);
}
static inline bool isLess(key_type_ref L, key_type_ref R) {
return ImutContainerInfo<T>::isLess(L,R);
}
static inline void Profile(FoldingSetNodeID& ID, value_type_ref V) {
ImutContainerInfo<T>::Profile(ID, V.first);
ImutContainerInfo<S>::Profile(ID, V.second);
}
};
template <typename KeyT, typename ValT,
typename ValInfo = ImutKeyValueInfo<KeyT,ValT> >
class ImmutableMap {
typedef typename ValInfo::value_type value_type;
typedef typename ValInfo::value_type_ref value_type_ref;
typedef typename ValInfo::key_type key_type;
typedef typename ValInfo::key_type_ref key_type_ref;
typedef typename ValInfo::data_type data_type;
typedef typename ValInfo::data_type_ref data_type_ref;
private:
typedef ImutAVLTree<ValInfo> TreeTy;
TreeTy* Root;
ImmutableMap(TreeTy* R) : Root(R) {}
public:
class Factory {
typename TreeTy::Factory F;
public:
Factory() {}
ImmutableMap GetEmptyMap() { return ImmutableMap(F.GetEmptyTree()); }
ImmutableMap Add(ImmutableMap Old, key_type_ref K, data_type_ref D) {
return ImmutableMap(F.Add(Old.Root,std::make_pair<key_type,data_type>(K,D)));
}
ImmutableMap Remove(ImmutableMap Old, key_type_ref K) {
return ImmutableMap(F.Remove(Old.Root,K));
}
private:
Factory(const Factory& RHS) {};
void operator=(const Factory& RHS) {};
};
friend class Factory;
bool contains(key_type_ref K) const {
return Root ? Root->contains(K) : false;
}
data_type* find(key_type_ref K) const {
if (Root) {
TreeTy* T = Root->find(K);
if (T) return &T->getValue().second;
}
return NULL;
}
bool operator==(ImmutableMap RHS) const {
return Root && RHS.Root ? Root->isEqual(*RHS.Root) : Root == RHS.Root;
}
bool operator!=(ImmutableMap RHS) const {
return Root && RHS.Root ? Root->isNotEqual(*RHS.Root) : Root != RHS.Root;
}
bool isEmpty() const { return !Root; }
//===--------------------------------------------------===//
// Foreach - A limited form of map iteration.
//===--------------------------------------------------===//
private:
template <typename Callback>
struct CBWrapper {
Callback C;
void operator()(value_type_ref V) { C(V.first,V.second); }
};
template <typename Callback>
struct CBWrapperRef {
Callback &C;
CBWrapperRef(Callback& c) : C(c) {}
void operator()(value_type_ref V) { C(V.first,V.second); }
};
public:
template <typename Callback>
void foreach(Callback& C) {
if (Root) {
CBWrapperRef<Callback> CB(C);
Root->foreach(CB);
}
}
template <typename Callback>
void foreach() {
if (Root) {
CBWrapper<Callback> CB;
Root->foreach(CB);
}
}
//===--------------------------------------------------===//
// For testing.
//===--------------------------------------------------===//
void verify() const { if (Root) Root->verify(); }
unsigned getHeight() const { return Root ? Root->getHeight() : 0; }
};
} // end namespace llvm
#endif