1//===- DebugStringTableSubsection.cpp - CodeView String Table -------------===//
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#include "llvm/DebugInfo/CodeView/DebugStringTableSubsection.h"
10#include "llvm/ADT/StringRef.h"
11#include "llvm/DebugInfo/CodeView/CodeView.h"
12#include "llvm/Support/BinaryStreamReader.h"
13#include "llvm/Support/BinaryStreamWriter.h"
14#include "llvm/Support/Error.h"
15#include <algorithm>
16#include <cassert>
17#include <cstdint>
18
19using namespace llvm;
20using namespace llvm::codeview;
21
22DebugStringTableSubsectionRef::DebugStringTableSubsectionRef()
23    : DebugSubsectionRef(DebugSubsectionKind::StringTable) {}
24
25Error DebugStringTableSubsectionRef::initialize(BinaryStreamRef Contents) {
26  Stream = Contents;
27  return Error::success();
28}
29
30Error DebugStringTableSubsectionRef::initialize(BinaryStreamReader &Reader) {
31  return Reader.readStreamRef(Stream);
32}
33
34Expected<StringRef>
35DebugStringTableSubsectionRef::getString(uint32_t Offset) const {
36  BinaryStreamReader Reader(Stream);
37  Reader.setOffset(Offset);
38  StringRef Result;
39  if (auto EC = Reader.readCString(Result))
40    return std::move(EC);
41  return Result;
42}
43
44DebugStringTableSubsection::DebugStringTableSubsection()
45    : DebugSubsection(DebugSubsectionKind::StringTable) {}
46
47uint32_t DebugStringTableSubsection::insert(StringRef S) {
48  auto P = StringToId.insert({S, StringSize});
49
50  // If a given string didn't exist in the string table, we want to increment
51  // the string table size and insert it into the reverse lookup.
52  if (P.second) {
53    IdToString.insert({P.first->getValue(), P.first->getKey()});
54    StringSize += S.size() + 1; // +1 for '\0'
55  }
56
57  return P.first->second;
58}
59
60uint32_t DebugStringTableSubsection::calculateSerializedSize() const {
61  return StringSize;
62}
63
64Error DebugStringTableSubsection::commit(BinaryStreamWriter &Writer) const {
65  uint32_t Begin = Writer.getOffset();
66  uint32_t End = Begin + StringSize;
67
68  // Write a null string at the beginning.
69  if (auto EC = Writer.writeCString(StringRef()))
70    return EC;
71
72  for (auto &Pair : StringToId) {
73    StringRef S = Pair.getKey();
74    uint32_t Offset = Begin + Pair.getValue();
75    Writer.setOffset(Offset);
76    if (auto EC = Writer.writeCString(S))
77      return EC;
78    assert(Writer.getOffset() <= End);
79  }
80
81  Writer.setOffset(End);
82  assert((End - Begin) == StringSize);
83  return Error::success();
84}
85
86uint32_t DebugStringTableSubsection::size() const { return StringToId.size(); }
87
88std::vector<uint32_t> DebugStringTableSubsection::sortedIds() const {
89  std::vector<uint32_t> Result;
90  Result.reserve(IdToString.size());
91  for (const auto &Entry : IdToString)
92    Result.push_back(Entry.first);
93  llvm::sort(Result);
94  return Result;
95}
96
97uint32_t DebugStringTableSubsection::getIdForString(StringRef S) const {
98  auto Iter = StringToId.find(S);
99  assert(Iter != StringToId.end());
100  return Iter->second;
101}
102
103StringRef DebugStringTableSubsection::getStringForId(uint32_t Id) const {
104  auto Iter = IdToString.find(Id);
105  assert(Iter != IdToString.end());
106  return Iter->second;
107}
108