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diff --git a/deps/v8/src/source-position-table.cc b/deps/v8/src/source-position-table.cc
new file mode 100644
index 0000000000..ef6d0773f9
--- /dev/null
+++ b/deps/v8/src/source-position-table.cc
@@ -0,0 +1,183 @@
+// Copyright 2016 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 "src/source-position-table.h"
+
+#include "src/log.h"
+#include "src/objects-inl.h"
+#include "src/objects.h"
+
+namespace v8 {
+namespace internal {
+
+// We'll use a simple encoding scheme to record the source positions.
+// Conceptually, each position consists of:
+// - code_offset: An integer index into the BytecodeArray or code.
+// - source_position: An integer index into the source string.
+// - position type: Each position is either a statement or an expression.
+//
+// The basic idea for the encoding is to use a variable-length integer coding,
+// where each byte contains 7 bits of payload data, and 1 'more' bit that
+// determines whether additional bytes follow. Additionally:
+// - we record the difference from the previous position,
+// - we just stuff one bit for the type into the code offset,
+// - we write least-significant bits first,
+// - we use zig-zag encoding to encode both positive and negative numbers.
+
+namespace {
+
+// Each byte is encoded as MoreBit | ValueBits.
+class MoreBit : public BitField8<bool, 7, 1> {};
+class ValueBits : public BitField8<unsigned, 0, 7> {};
+
+// Helper: Add the offsets from 'other' to 'value'. Also set is_statement.
+void AddAndSetEntry(PositionTableEntry& value,
+                    const PositionTableEntry& other) {
+  value.code_offset += other.code_offset;
+  value.source_position += other.source_position;
+  value.is_statement = other.is_statement;
+}
+
+// Helper: Substract the offsets from 'other' from 'value'.
+void SubtractFromEntry(PositionTableEntry& value,
+                       const PositionTableEntry& other) {
+  value.code_offset -= other.code_offset;
+  value.source_position -= other.source_position;
+}
+
+// Helper: Encode an integer.
+void EncodeInt(ZoneVector<byte>& bytes, int value) {
+  // Zig-zag encoding.
+  static const int kShift = kIntSize * kBitsPerByte - 1;
+  value = ((value << 1) ^ (value >> kShift));
+  DCHECK_GE(value, 0);
+  unsigned int encoded = static_cast<unsigned int>(value);
+  bool more;
+  do {
+    more = encoded > ValueBits::kMax;
+    bytes.push_back(MoreBit::encode(more) |
+                    ValueBits::encode(encoded & ValueBits::kMask));
+    encoded >>= ValueBits::kSize;
+  } while (more);
+}
+
+// Encode a PositionTableEntry.
+void EncodeEntry(ZoneVector<byte>& bytes, const PositionTableEntry& entry) {
+  // We only accept ascending code offsets.
+  DCHECK(entry.code_offset >= 0);
+  // Since code_offset is not negative, we use sign to encode is_statement.
+  EncodeInt(bytes,
+            entry.is_statement ? entry.code_offset : -entry.code_offset - 1);
+  EncodeInt(bytes, entry.source_position);
+}
+
+// Helper: Decode an integer.
+void DecodeInt(ByteArray* bytes, int* index, int* v) {
+  byte current;
+  int shift = 0;
+  int decoded = 0;
+  bool more;
+  do {
+    current = bytes->get((*index)++);
+    decoded |= ValueBits::decode(current) << shift;
+    more = MoreBit::decode(current);
+    shift += ValueBits::kSize;
+  } while (more);
+  DCHECK_GE(decoded, 0);
+  decoded = (decoded >> 1) ^ (-(decoded & 1));
+  *v = decoded;
+}
+
+void DecodeEntry(ByteArray* bytes, int* index, PositionTableEntry* entry) {
+  int tmp;
+  DecodeInt(bytes, index, &tmp);
+  if (tmp >= 0) {
+    entry->is_statement = true;
+    entry->code_offset = tmp;
+  } else {
+    entry->is_statement = false;
+    entry->code_offset = -(tmp + 1);
+  }
+  DecodeInt(bytes, index, &entry->source_position);
+}
+
+}  // namespace
+
+SourcePositionTableBuilder::SourcePositionTableBuilder(
+    Zone* zone, SourcePositionTableBuilder::RecordingMode mode)
+    : mode_(mode),
+      bytes_(zone),
+#ifdef ENABLE_SLOW_DCHECKS
+      raw_entries_(zone),
+#endif
+      previous_() {
+}
+
+void SourcePositionTableBuilder::AddPosition(size_t code_offset,
+                                             int source_position,
+                                             bool is_statement) {
+  if (Omit()) return;
+  int offset = static_cast<int>(code_offset);
+  AddEntry({offset, source_position, is_statement});
+}
+
+void SourcePositionTableBuilder::AddEntry(const PositionTableEntry& entry) {
+  PositionTableEntry tmp(entry);
+  SubtractFromEntry(tmp, previous_);
+  EncodeEntry(bytes_, tmp);
+  previous_ = entry;
+#ifdef ENABLE_SLOW_DCHECKS
+  raw_entries_.push_back(entry);
+#endif
+}
+
+Handle<ByteArray> SourcePositionTableBuilder::ToSourcePositionTable(
+    Isolate* isolate, Handle<AbstractCode> code) {
+  if (bytes_.empty()) return isolate->factory()->empty_byte_array();
+  DCHECK(!Omit());
+
+  Handle<ByteArray> table = isolate->factory()->NewByteArray(
+      static_cast<int>(bytes_.size()), TENURED);
+
+  MemCopy(table->GetDataStartAddress(), &*bytes_.begin(), bytes_.size());
+
+  LOG_CODE_EVENT(isolate, CodeLinePosInfoRecordEvent(*code, *table));
+
+#ifdef ENABLE_SLOW_DCHECKS
+  // Brute force testing: Record all positions and decode
+  // the entire table to verify they are identical.
+  auto raw = raw_entries_.begin();
+  for (SourcePositionTableIterator encoded(*table); !encoded.done();
+       encoded.Advance(), raw++) {
+    DCHECK(raw != raw_entries_.end());
+    DCHECK_EQ(encoded.code_offset(), raw->code_offset);
+    DCHECK_EQ(encoded.source_position(), raw->source_position);
+    DCHECK_EQ(encoded.is_statement(), raw->is_statement);
+  }
+  DCHECK(raw == raw_entries_.end());
+  // No additional source positions after creating the table.
+  mode_ = OMIT_SOURCE_POSITIONS;
+#endif
+  return table;
+}
+
+SourcePositionTableIterator::SourcePositionTableIterator(ByteArray* byte_array)
+    : table_(byte_array), index_(0), current_() {
+  Advance();
+}
+
+void SourcePositionTableIterator::Advance() {
+  DCHECK(!done());
+  DCHECK(index_ >= 0 && index_ <= table_->length());
+  if (index_ == table_->length()) {
+    index_ = kDone;
+  } else {
+    PositionTableEntry tmp;
+    DecodeEntry(table_, &index_, &tmp);
+    AddAndSetEntry(current_, tmp);
+  }
+}
+
+}  // namespace internal
+}  // namespace v8