Use source position table for unoptimized code.

src/interpreter/source-position-table.h

-// 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.
-
-#ifndef V8_INTERPRETER_SOURCE_POSITION_TABLE_H_
-#define V8_INTERPRETER_SOURCE_POSITION_TABLE_H_
-
-#include "src/assert-scope.h"
-#include "src/checks.h"
-#include "src/handles.h"
-#include "src/log.h"
-#include "src/zone-containers.h"
-
-namespace v8 {
-namespace internal {
-
-class BytecodeArray;
-class ByteArray;
-class Isolate;
-class Zone;
-
-namespace interpreter {
-
-struct PositionTableEntry {
-  PositionTableEntry()
-      : bytecode_offset(0), source_position(0), is_statement(false) {}
-  PositionTableEntry(int bytecode, int source, bool statement)
-      : bytecode_offset(bytecode),
-        source_position(source),
-        is_statement(statement) {}
-
-  int bytecode_offset;
-  int source_position;
-  bool is_statement;
-};
-
-class SourcePositionTableBuilder final : public PositionsRecorder {
- public:
-  SourcePositionTableBuilder(Isolate* isolate, Zone* zone)
-      : isolate_(isolate),
-        bytes_(zone),
-#ifdef ENABLE_SLOW_DCHECKS
-        raw_entries_(zone),
-#endif
-        previous_() {
-  }
-
-  void AddPosition(size_t bytecode_offset, int source_position,
-                   bool is_statement);
-  Handle<ByteArray> ToSourcePositionTable();
-
- private:
-  void AddEntry(const PositionTableEntry& entry);
-  void CommitEntry();
-
-  Isolate* isolate_;
-  ZoneVector<byte> bytes_;
-#ifdef ENABLE_SLOW_DCHECKS
-  ZoneVector<PositionTableEntry> raw_entries_;
-#endif
-  PositionTableEntry previous_;   // Previously written entry, to compute delta.
-};
-
-class SourcePositionTableIterator {
- public:
-  explicit SourcePositionTableIterator(ByteArray* byte_array);
-
-  void Advance();
-
-  int bytecode_offset() const {
-    DCHECK(!done());
-    return current_.bytecode_offset;
-  }
-  int source_position() const {
-    DCHECK(!done());
-    return current_.source_position;
-  }
-  bool is_statement() const {
-    DCHECK(!done());
-    return current_.is_statement;
-  }
-  bool done() const { return index_ == kDone; }
-
- private:
-  static const int kDone = -1;
-
-  ByteArray* table_;
-  int index_;
-  PositionTableEntry current_;
-  DisallowHeapAllocation no_gc;
-};
-
-}  // namespace interpreter
-}  // namespace internal
-}  // namespace v8
-
-#endif  // V8_INTERPRETER_SOURCE_POSITION_TABLE_H_