Uniform and precise source positions for inlining

src/compiler/source-position.h

-// Copyright 2014 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_COMPILER_SOURCE_POSITION_H_
-#define V8_COMPILER_SOURCE_POSITION_H_
-
-#include "src/base/compiler-specific.h"
-#include "src/compiler/node-aux-data.h"
-#include "src/globals.h"
-
-namespace v8 {
-namespace internal {
-namespace compiler {
-
-// Encapsulates encoding and decoding of sources positions from which Nodes
-// originated.
-class SourcePosition final {
- public:
-  explicit SourcePosition(int raw = kUnknownPosition) : raw_(raw) {}
-
-  static SourcePosition Unknown() { return SourcePosition(kUnknownPosition); }
-  bool IsUnknown() const { return raw() == kUnknownPosition; }
-  bool IsKnown() const { return raw() != kUnknownPosition; }
-
-  int raw() const { return raw_; }
-
- private:
-  static const int kUnknownPosition = kNoSourcePosition;
-  int raw_;
-};
-
-
-inline bool operator==(const SourcePosition& lhs, const SourcePosition& rhs) {
-  return lhs.raw() == rhs.raw();
-}
-
-inline bool operator!=(const SourcePosition& lhs, const SourcePosition& rhs) {
-  return !(lhs == rhs);
-}
-
-class V8_EXPORT_PRIVATE SourcePositionTable final
-    : public NON_EXPORTED_BASE(ZoneObject) {
- public:
-  class Scope final {
-   public:
-    Scope(SourcePositionTable* source_positions, SourcePosition position)
-        : source_positions_(source_positions),
-          prev_position_(source_positions->current_position_) {
-      Init(position);
-    }
-    Scope(SourcePositionTable* source_positions, Node* node)
-        : source_positions_(source_positions),
-          prev_position_(source_positions->current_position_) {
-      Init(source_positions_->GetSourcePosition(node));
-    }
-    ~Scope() { source_positions_->current_position_ = prev_position_; }
-
-   private:
-    void Init(SourcePosition position) {
-      if (position.IsKnown()) source_positions_->current_position_ = position;
-    }
-
-    SourcePositionTable* const source_positions_;
-    SourcePosition const prev_position_;
-    DISALLOW_COPY_AND_ASSIGN(Scope);
-  };
-
-  explicit SourcePositionTable(Graph* graph);
-
-  void AddDecorator();
-  void RemoveDecorator();
-
-  SourcePosition GetSourcePosition(Node* node) const;
-  void SetSourcePosition(Node* node, SourcePosition position);
-
-  void set_current_position(int position) {
-    current_position_ = SourcePosition(position);
-  }
-
-  void Print(std::ostream& os) const;
-
- private:
-  class Decorator;
-
-  Graph* const graph_;
-  Decorator* decorator_;
-  SourcePosition current_position_;
-  NodeAuxData<SourcePosition> table_;
-
-  DISALLOW_COPY_AND_ASSIGN(SourcePositionTable);
-};
-
-}  // namespace compiler
-}  // namespace internal
-}  // namespace v8
-
-#endif  // V8_COMPILER_SOURCE_POSITION_H_