1//===-- LVStringPool.h ------------------------------------------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file defines the LVStringPool class, which is used to implement a
10// basic string pool table.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_DEBUGINFO_LOGICALVIEW_CORE_LVSTRINGPOOL_H
15#define LLVM_DEBUGINFO_LOGICALVIEW_CORE_LVSTRINGPOOL_H
16
17#include "llvm/ADT/StringMap.h"
18#include "llvm/Support/Allocator.h"
19#include "llvm/Support/Debug.h"
20#include "llvm/Support/Format.h"
21#include "llvm/Support/raw_ostream.h"
22#include <iomanip>
23#include <vector>
24
25namespace llvm {
26namespace logicalview {
27
28class LVStringPool {
29  static constexpr size_t BadIndex = std::numeric_limits<size_t>::max();
30  using TableType = StringMap<size_t, BumpPtrAllocator>;
31  using ValueType = TableType::value_type;
32  BumpPtrAllocator Allocator;
33  TableType StringTable;
34  std::vector<ValueType *> Entries;
35
36public:
37  LVStringPool() { getIndex(""); }
38  LVStringPool(LVStringPool const &other) = delete;
39  LVStringPool(LVStringPool &&other) = delete;
40  ~LVStringPool() = default;
41
42  bool isValidIndex(size_t Index) const { return Index != BadIndex; }
43
44  // Return number of strings in the pool. The empty string is allocated
45  // at the slot zero. We substract 1 to indicate the number of non empty
46  // strings.
47  size_t getSize() const { return Entries.size() - 1; }
48
49  // Return the index for the specified key, otherwise 'BadIndex'.
50  size_t findIndex(StringRef Key) const {
51    TableType::const_iterator Iter = StringTable.find(Key);
52    if (Iter != StringTable.end())
53      return Iter->second;
54    return BadIndex;
55  }
56
57  // Return an index for the specified key.
58  size_t getIndex(StringRef Key) {
59    size_t Index = findIndex(Key);
60    if (isValidIndex(Index))
61      return Index;
62    size_t Value = Entries.size();
63    ValueType *Entry = ValueType::create(Key, Allocator, std::move(Value));
64    StringTable.insert(Entry);
65    Entries.push_back(Entry);
66    return Value;
67  }
68
69  // Given the index, return its corresponding string.
70  StringRef getString(size_t Index) const {
71    return (Index >= Entries.size()) ? StringRef() : Entries[Index]->getKey();
72  }
73
74  void print(raw_ostream &OS) const {
75    if (!Entries.empty()) {
76      OS << "\nString Pool:\n";
77      for (const ValueType *Entry : Entries)
78        OS << "Index: " << Entry->getValue() << ", "
79           << "Key: '" << Entry->getKey() << "'\n";
80    }
81  }
82
83#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
84  void dump() const { print(dbgs()); }
85#endif
86};
87
88} // namespace logicalview
89} // end namespace llvm
90
91#endif // LLVM_DEBUGINFO_LOGICALVIEW_CORE_LVSTRINGPOOL_H
92