1 files changed, 102 insertions, 0 deletions
diff --git a/deps/v8/src/code-comments.cc b/deps/v8/src/code-comments.cc
new file mode 100644
index 0000000000..6e64eb7fa1
--- /dev/null
+++ b/deps/v8/src/code-comments.cc
@@ -0,0 +1,102 @@
+// Copyright 2018 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include <cstring>
+#include <iomanip>
+
+#include "src/assembler-inl.h"
+#include "src/code-comments.h"
+
+namespace v8 {
+namespace internal {
+
+namespace {
+static constexpr uint8_t kOffsetToFirstCommentEntry = kUInt32Size;
+static constexpr uint8_t kOffsetToPCOffset = 0;
+static constexpr uint8_t kOffsetToCommentSize = kOffsetToPCOffset + kUInt32Size;
+static constexpr uint8_t kOffsetToCommentString =
+    kOffsetToCommentSize + kUInt32Size;
+}  // namespace
+
+uint32_t CodeCommentEntry::comment_length() const {
+  return static_cast<uint32_t>(comment.size() + 1);
+}
+
+uint32_t CodeCommentEntry::size() const {
+  return kOffsetToCommentString + comment_length();
+}
+
+CodeCommentsIterator::CodeCommentsIterator(Address code_comments_start)
+    : code_comments_start_(code_comments_start),
+      current_entry_(code_comments_start + kOffsetToFirstCommentEntry) {}
+
+uint32_t CodeCommentsIterator::size() const {
+  return code_comments_start_ != kNullAddress
+             ? *reinterpret_cast<uint32_t*>(code_comments_start_)
+             : 0;
+}
+
+const char* CodeCommentsIterator::GetComment() const {
+  const char* comment_string =
+      reinterpret_cast<const char*>(current_entry_ + kOffsetToCommentString);
+  CHECK_EQ(GetCommentSize(), strlen(comment_string) + 1);
+  return comment_string;
+}
+
+uint32_t CodeCommentsIterator::GetCommentSize() const {
+  return *reinterpret_cast<uint32_t*>(current_entry_ + kOffsetToCommentSize);
+}
+
+uint32_t CodeCommentsIterator::GetPCOffset() const {
+  return *reinterpret_cast<uint32_t*>(current_entry_ + kOffsetToPCOffset);
+}
+
+void CodeCommentsIterator::Next() {
+  current_entry_ += kOffsetToCommentString + GetCommentSize();
+}
+
+bool CodeCommentsIterator::HasCurrent() const {
+  return current_entry_ < code_comments_start_ + size();
+}
+
+void CodeCommentsWriter::Emit(Assembler* assm) {
+  assm->dd(section_size());
+  for (auto i = comments_.begin(); i != comments_.end(); ++i) {
+    assm->dd(i->pc_offset);
+    assm->dd(i->comment_length());
+    for (char c : i->comment) {
+      EnsureSpace ensure_space(assm);
+      assm->db(c);
+    }
+    assm->db('\0');
+  }
+}
+
+void CodeCommentsWriter::Add(uint32_t pc_offset, std::string comment) {
+  CodeCommentEntry entry = {pc_offset, std::move(comment)};
+  byte_count_ += entry.size();
+  comments_.push_back(std::move(entry));
+}
+
+size_t CodeCommentsWriter::entry_count() const { return comments_.size(); }
+uint32_t CodeCommentsWriter::section_size() const {
+  return kOffsetToFirstCommentEntry + static_cast<uint32_t>(byte_count_);
+}
+
+void PrintCodeCommentsSection(std::ostream& out, Address code_comments_start) {
+  CodeCommentsIterator it(code_comments_start);
+  out << "CodeComments (size = " << it.size() << ")\n";
+  if (it.HasCurrent()) {
+    out << std::setw(6) << "pc" << std::setw(6) << "len"
+        << " comment\n";
+  }
+  for (; it.HasCurrent(); it.Next()) {
+    out << std::hex << std::setw(6) << it.GetPCOffset() << std::dec
+        << std::setw(6) << it.GetCommentSize() << " (" << it.GetComment()
+        << ")\n";
+  }
+}
+
+}  // namespace internal
+}  // namespace v8