Function print_remembered_set

deps/v8/tools/windbg.js:792–862

(chunk_addr, set_id = 0)

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// set ids: 0 = OLD_TO_NEW, 1 = 0 = OLD_TO_OLD
function print_remembered_set(chunk_addr, set_id = 0) {
  if (!chunk_addr) {
    if (isolate_address == 0) {
      print("Please call !set_iso(isolate_address) or provide chunk address.");
      return;
    }

    let iso = cast(isolate_address, "v8::internal::Isolate");
    let h = iso.heap_;
    let chunks = [];
    get_chunks_space('old', h.old_space_.memory_chunk_list_.front_, chunks);
    get_chunks_space('lo', h.lo_space_.memory_chunk_list_.front_, chunks);
    for (let c of chunks) {
      try {
        print_remembered_set(c.address);
      }
      catch (e) {
        print(`failed to process chunk ${hex(c.address)} due to ${e.message}`);
      }
    }
    return;
  }

  print(`Remembered set in chunk ${hex(chunk_addr)}`);
  let chunk = cast(chunk_addr, "v8::internal::MemoryChunk");

  // chunk.slot_set_ is an array of SlotSet's. For standard pages there is 0 or
  // 1 item in the array, but for large pages there will be more.
  const page_size = 256 * 1024;
  const sets_count = Math.floor((chunk.size_ + page_size - 1) / page_size);
  let rs = chunk.slot_set_[set_id];
  if (rs.isNull) {
    print(`  <empty>`);
    return;
  }
  if (rs[0].page_start_ != chunk_addr) {
    print(`page_start_ [${hex(rs.page_start_)}] doesn't match chunk_addr!`);
    return;
  }

  const ptr_size = tagged_size();
  let count = 0;
  for (let s = 0; s < sets_count; s++){
    const buckets_count = rs[s].buckets_.Count();
    for (let b = 0; b < buckets_count; b++) {
      let bucket = rs[s].buckets_[b];
      if (bucket.isNull) continue;
      // there are 32 cells in each bucket, cell's size is 32 bits
      print(`  bucket ${hex(bucket.address.asNumber())}:`);
      const first_cell = bucket.address.asNumber();
      for (let c = 0; c < 32; c++) {
        let cell = host.memory.readMemoryValues(
          first_cell + c * 4, 1, 4 /*size to read*/)[0];
        if (cell == 0) continue;
        let mask = 1;
        for (let bit = 0; bit < 32; bit++){
          if (cell & mask) {
            count++;