1// Copyright 2015 the V8 project authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#ifndef V8_COMPILER_ALL_NODES_H_
6#define V8_COMPILER_ALL_NODES_H_
7
8#include "src/compiler/node.h"
9#include "src/zone/zone-containers.h"
10
11namespace v8 {
12namespace internal {
13namespace compiler {
14
15// A helper utility that traverses the graph and gathers all nodes reachable
16// from end.
17class AllNodes {
18 public:
19  // Constructor. Traverses the graph and builds the {reachable} set of nodes
20  // reachable from {end}. When {only_inputs} is true, find the nodes
21  // reachable through input edges; these are all live nodes.
22  AllNodes(Zone* local_zone, Node* end, const Graph* graph,
23           bool only_inputs = true);
24  // Constructor. Traverses the graph and builds the {reachable} set of nodes
25  // reachable from the End node.
26  AllNodes(Zone* local_zone, const Graph* graph, bool only_inputs = true);
27
28  bool IsLive(const Node* node) const {
29    CHECK(only_inputs_);
30    return IsReachable(node);
31  }
32
33  bool IsReachable(const Node* node) const {
34    if (!node) return false;
35    size_t id = node->id();
36    return id < is_reachable_.size() && is_reachable_[id];
37  }
38
39  NodeVector reachable;  // Nodes reachable from end.
40
41 private:
42  void Mark(Zone* local_zone, Node* end, const Graph* graph);
43
44  BoolVector is_reachable_;
45  const bool only_inputs_;
46};
47
48}  // namespace compiler
49}  // namespace internal
50}  // namespace v8
51
52#endif  // V8_COMPILER_ALL_NODES_H_
53