Land the Fan (disabled)

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/assembler.h"
+#include "src/compiler/node-aux-data.h"
+
+namespace v8 {
+namespace internal {
+namespace compiler {
+
+// Encapsulates encoding and decoding of sources positions from which Nodes
+// originated.
+class SourcePosition V8_FINAL {
+ public:
+  explicit SourcePosition(int raw = kUnknownPosition) : raw_(raw) {}
+
+  static SourcePosition Unknown() { return SourcePosition(kUnknownPosition); }
+  bool IsUnknown() const { return raw() == kUnknownPosition; }
+
+  static SourcePosition Invalid() { return SourcePosition(kInvalidPosition); }
+  bool IsInvalid() const { return raw() == kInvalidPosition; }
+
+  int raw() const { return raw_; }
+
+ private:
+  static const int kInvalidPosition = -2;
+  static const int kUnknownPosition = RelocInfo::kNoPosition;
+  STATIC_ASSERT(kInvalidPosition != kUnknownPosition);
+  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 SourcePositionTable V8_FINAL {
+ public:
+  class Scope {
+   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.IsUnknown() || prev_position_.IsInvalid()) {
+        source_positions_->current_position_ = position;
+      }
+    }
+
+    SourcePositionTable* source_positions_;
+    SourcePosition prev_position_;
+    DISALLOW_COPY_AND_ASSIGN(Scope);
+  };
+
+  explicit SourcePositionTable(Graph* graph);
+  ~SourcePositionTable() {
+    if (decorator_ != NULL) RemoveDecorator();
+  }
+
+  void AddDecorator();
+  void RemoveDecorator();
+
+  SourcePosition GetSourcePosition(Node* node);
+
+ private:
+  class Decorator;
+
+  Graph* graph_;
+  Decorator* decorator_;
+  SourcePosition current_position_;
+  NodeAuxData<SourcePosition> table_;
+
+  DISALLOW_COPY_AND_ASSIGN(SourcePositionTable);
+};
+
+}  // namespace compiler
+}  // namespace internal
+}  // namespace v8
+
+#endif