1 files changed, 107 insertions, 0 deletions
diff --git a/llvm/lib/DebugInfo/CodeView/DebugStringTableSubsection.cpp b/llvm/lib/DebugInfo/CodeView/DebugStringTableSubsection.cpp
new file mode 100644
index 0000000000000..63342749918d8
--- /dev/null
+++ b/llvm/lib/DebugInfo/CodeView/DebugStringTableSubsection.cpp
@@ -0,0 +1,107 @@
+//===- DebugStringTableSubsection.cpp - CodeView String Table -------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/DebugInfo/CodeView/DebugStringTableSubsection.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/DebugInfo/CodeView/CodeView.h"
+#include "llvm/Support/BinaryStreamReader.h"
+#include "llvm/Support/BinaryStreamWriter.h"
+#include "llvm/Support/Error.h"
+#include <algorithm>
+#include <cassert>
+#include <cstdint>
+
+using namespace llvm;
+using namespace llvm::codeview;
+
+DebugStringTableSubsectionRef::DebugStringTableSubsectionRef()
+    : DebugSubsectionRef(DebugSubsectionKind::StringTable) {}
+
+Error DebugStringTableSubsectionRef::initialize(BinaryStreamRef Contents) {
+  Stream = Contents;
+  return Error::success();
+}
+
+Error DebugStringTableSubsectionRef::initialize(BinaryStreamReader &Reader) {
+  return Reader.readStreamRef(Stream);
+}
+
+Expected<StringRef>
+DebugStringTableSubsectionRef::getString(uint32_t Offset) const {
+  BinaryStreamReader Reader(Stream);
+  Reader.setOffset(Offset);
+  StringRef Result;
+  if (auto EC = Reader.readCString(Result))
+    return std::move(EC);
+  return Result;
+}
+
+DebugStringTableSubsection::DebugStringTableSubsection()
+    : DebugSubsection(DebugSubsectionKind::StringTable) {}
+
+uint32_t DebugStringTableSubsection::insert(StringRef S) {
+  auto P = StringToId.insert({S, StringSize});
+
+  // If a given string didn't exist in the string table, we want to increment
+  // the string table size and insert it into the reverse lookup.
+  if (P.second) {
+    IdToString.insert({P.first->getValue(), P.first->getKey()});
+    StringSize += S.size() + 1; // +1 for '\0'
+  }
+
+  return P.first->second;
+}
+
+uint32_t DebugStringTableSubsection::calculateSerializedSize() const {
+  return StringSize;
+}
+
+Error DebugStringTableSubsection::commit(BinaryStreamWriter &Writer) const {
+  uint32_t Begin = Writer.getOffset();
+  uint32_t End = Begin + StringSize;
+
+  // Write a null string at the beginning.
+  if (auto EC = Writer.writeCString(StringRef()))
+    return EC;
+
+  for (auto &Pair : StringToId) {
+    StringRef S = Pair.getKey();
+    uint32_t Offset = Begin + Pair.getValue();
+    Writer.setOffset(Offset);
+    if (auto EC = Writer.writeCString(S))
+      return EC;
+    assert(Writer.getOffset() <= End);
+  }
+
+  Writer.setOffset(End);
+  assert((End - Begin) == StringSize);
+  return Error::success();
+}
+
+uint32_t DebugStringTableSubsection::size() const { return StringToId.size(); }
+
+std::vector<uint32_t> DebugStringTableSubsection::sortedIds() const {
+  std::vector<uint32_t> Result;
+  Result.reserve(IdToString.size());
+  for (const auto &Entry : IdToString)
+    Result.push_back(Entry.first);
+  llvm::sort(Result);
+  return Result;
+}
+
+uint32_t DebugStringTableSubsection::getIdForString(StringRef S) const {
+  auto Iter = StringToId.find(S);
+  assert(Iter != StringToId.end());
+  return Iter->second;
+}
+
+StringRef DebugStringTableSubsection::getStringForId(uint32_t Id) const {
+  auto Iter = IdToString.find(Id);
+  assert(Iter != IdToString.end());
+  return Iter->second;
+}