//===--- ImmutableMap.h - Immutable (functional) map interface --*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
///
/// \file
/// This file defines the ImmutableMap class.
///
//===----------------------------------------------------------------------===//
#ifndef LLVM_ADT_IMMUTABLEMAP_H
#define LLVM_ADT_IMMUTABLEMAP_H
#include "llvm/ADT/FoldingSet.h"
#include "llvm/ADT/ImmutableSet.h"
#include "llvm/Support/Allocator.h"
#include <utility>
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 {
using value_type = const std::pair<T,S>;
using value_type_ref = const value_type&;
using key_type = const T;
using key_type_ref = const T&;
using data_type = const S;
using data_type_ref = const S&;
static inline key_type_ref KeyOfValue(value_type_ref V) {
return V.first;
}
static inline data_type_ref DataOfValue(value_type_ref V) {
return V.second;
}
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 bool isDataEqual(data_type_ref L, data_type_ref R) {
return ImutContainerInfo<S>::isEqual(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 {
public:
using value_type = typename ValInfo::value_type;
using value_type_ref = typename ValInfo::value_type_ref;
using key_type = typename ValInfo::key_type;
using key_type_ref = typename ValInfo::key_type_ref;
using data_type = typename ValInfo::data_type;
using data_type_ref = typename ValInfo::data_type_ref;
using TreeTy = ImutAVLTree<ValInfo>;
protected:
IntrusiveRefCntPtr<TreeTy> Root;
public:
/// Constructs a map from a pointer to a tree root. In general one
/// should use a Factory object to create maps instead of directly
/// invoking the constructor, but there are cases where make this
/// constructor public is useful.
explicit ImmutableMap(const TreeTy *R) : Root(const_cast<TreeTy *>(R)) {}
class Factory {
typename TreeTy::Factory F;
const bool Canonicalize;
public:
Factory(bool canonicalize = true) : Canonicalize(canonicalize) {}
Factory(BumpPtrAllocator &Alloc, bool canonicalize = true)
: F(Alloc), Canonicalize(canonicalize) {}
Factory(const Factory &) = delete;
Factory &operator=(const Factory &) = delete;
ImmutableMap getEmptyMap() { return ImmutableMap(F.getEmptyTree()); }
[[nodiscard]] ImmutableMap add(ImmutableMap Old, key_type_ref K,
data_type_ref D) {
TreeTy *T = F.add(Old.Root.get(), std::pair<key_type, data_type>(K, D));
return ImmutableMap(Canonicalize ? F.getCanonicalTree(T): T);
}
[[nodiscard]] ImmutableMap remove(ImmutableMap Old, key_type_ref K) {
TreeTy *T = F.remove(Old.Root.get(), K);
return ImmutableMap(Canonicalize ? F.getCanonicalTree(T): T);
}
typename TreeTy::Factory *getTreeFactory() const {
return const_cast<typename TreeTy::Factory *>(&F);
}
};
bool contains(key_type_ref K) const {
return Root ? Root->contains(K) : false;
}
bool operator==(const ImmutableMap &RHS) const {
return Root && RHS.Root ? Root->isEqual(*RHS.Root.get()) : Root == RHS.Root;
}
bool operator!=(const ImmutableMap &RHS) const {
return Root && RHS.Root ? Root->isNotEqual(*RHS.Root.get())
: Root != RHS.Root;
}
TreeTy *getRoot() const {
if (Root) { Root->retain(); }
return Root.get();
}
TreeTy *getRootWithoutRetain() const { return Root.get(); }
void manualRetain() {
if (Root) Root->retain();
}
void manualRelease() {
if (Root) Root->release();
}
bool isEmpty() const { return !Root; }
public:
//===--------------------------------------------------===//
// For testing.
//===--------------------------------------------------===//
void verify() const { if (Root) Root->verify(); }
//===--------------------------------------------------===//
// Iterators.
//===--------------------------------------------------===//
class iterator : public ImutAVLValueIterator<ImmutableMap> {
friend class ImmutableMap;
iterator() = default;
explicit iterator(TreeTy *Tree) : iterator::ImutAVLValueIterator(Tree) {}
public:
key_type_ref getKey() const { return (*this)->first; }
data_type_ref getData() const { return (*this)->second; }
};
iterator begin() const { return iterator(Root.get()); }
iterator end() const { return iterator(); }
data_type* lookup(key_type_ref K) const {
if (Root) {
TreeTy* T = Root->find(K);
if (T) return &T->getValue().second;
}
return nullptr;
}
/// getMaxElement - Returns the <key,value> pair in the ImmutableMap for
/// which key is the highest in the ordering of keys in the map. This
/// method returns NULL if the map is empty.
value_type* getMaxElement() const {
return Root ? &(Root->getMaxElement()->getValue()) : nullptr;
}
//===--------------------------------------------------===//
// Utility methods.
//===--------------------------------------------------===//
unsigned getHeight() const { return Root ? Root->getHeight() : 0; }
static inline void Profile(FoldingSetNodeID& ID, const ImmutableMap& M) {
ID.AddPointer(M.Root.get());
}
inline void Profile(FoldingSetNodeID& ID) const {
return Profile(ID,*this);
}
};
// NOTE: This will possibly become the new implementation of ImmutableMap some day.
template <typename KeyT, typename ValT,
typename ValInfo = ImutKeyValueInfo<KeyT,ValT>>
class ImmutableMapRef {
public:
using value_type = typename ValInfo::value_type;
using value_type_ref = typename ValInfo::value_type_ref;
using key_type = typename ValInfo::key_type;
using key_type_ref = typename ValInfo::key_type_ref;
using data_type = typename ValInfo::data_type;
using data_type_ref = typename ValInfo::data_type_ref;
using TreeTy = ImutAVLTree<ValInfo>;
using FactoryTy = typename TreeTy::Factory;
protected:
IntrusiveRefCntPtr<TreeTy> Root;
FactoryTy *Factory;
public:
/// Constructs a map from a pointer to a tree root. In general one
/// should use a Factory object to create maps instead of directly
/// invoking the constructor, but there are cases where make this
/// constructor public is useful.
ImmutableMapRef(const TreeTy *R, FactoryTy *F)
: Root(const_cast<TreeTy *>(R)), Factory(F) {}
ImmutableMapRef(const ImmutableMap<KeyT, ValT> &X,
typename ImmutableMap<KeyT, ValT>::Factory &F)
: Root(X.getRootWithoutRetain()), Factory(F.getTreeFactory()) {}
static inline ImmutableMapRef getEmptyMap(FactoryTy *F) {
return ImmutableMapRef(nullptr, F);
}
void manualRetain() {
if (Root) Root->retain();
}
void manualRelease() {
if (Root) Root->release();
}
ImmutableMapRef add(key_type_ref K, data_type_ref D) const {
TreeTy *NewT =
Factory->add(Root.get(), std::pair<key_type, data_type>(K, D));
return ImmutableMapRef(NewT, Factory);
}
ImmutableMapRef remove(key_type_ref K) const {
TreeTy *NewT = Factory->remove(Root.get(), K);
return ImmutableMapRef(NewT, Factory);
}
bool contains(key_type_ref K) const {
return Root ? Root->contains(K) : false;
}
ImmutableMap<KeyT, ValT> asImmutableMap() const {
return ImmutableMap<KeyT, ValT>(Factory->getCanonicalTree(Root.get()));
}
bool operator==(const ImmutableMapRef &RHS) const {
return Root && RHS.Root ? Root->isEqual(*RHS.Root.get()) : Root == RHS.Root;
}
bool operator!=(const ImmutableMapRef &RHS) const {
return Root && RHS.Root ? Root->isNotEqual(*RHS.Root.get())
: Root != RHS.Root;
}
bool isEmpty() const { return !Root; }
//===--------------------------------------------------===//
// For testing.
//===--------------------------------------------------===//
void verify() const {
if (Root)
Root->verify();
}
//===--------------------------------------------------===//
// Iterators.
//===--------------------------------------------------===//
class iterator : public ImutAVLValueIterator<ImmutableMapRef> {
friend class ImmutableMapRef;
iterator() = default;
explicit iterator(TreeTy *Tree) : iterator::ImutAVLValueIterator(Tree) {}
public:
key_type_ref getKey() const { return (*this)->first; }
data_type_ref getData() const { return (*this)->second; }
};
iterator begin() const { return iterator(Root.get()); }
iterator end() const { return iterator(); }
data_type *lookup(key_type_ref K) const {
if (Root) {
TreeTy* T = Root->find(K);
if (T) return &T->getValue().second;
}
return nullptr;
}
/// getMaxElement - Returns the <key,value> pair in the ImmutableMap for
/// which key is the highest in the ordering of keys in the map. This
/// method returns NULL if the map is empty.
value_type* getMaxElement() const {
return Root ? &(Root->getMaxElement()->getValue()) : nullptr;
}
//===--------------------------------------------------===//
// Utility methods.
//===--------------------------------------------------===//
unsigned getHeight() const { return Root ? Root->getHeight() : 0; }
static inline void Profile(FoldingSetNodeID &ID, const ImmutableMapRef &M) {
ID.AddPointer(M.Root.get());
}
inline void Profile(FoldingSetNodeID &ID) const { return Profile(ID, *this); }
};
} // end namespace llvm
#endif // LLVM_ADT_IMMUTABLEMAP_H