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 
11 namespace v8 {
12 namespace internal {
13 namespace compiler {
14 
15 // A helper utility that traverses the graph and gathers all nodes reachable
16 // from end.
17 class 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 
IsLive(const Node * node)28   bool IsLive(const Node* node) const {
29     CHECK(only_inputs_);
30     return IsReachable(node);
31   }
32 
IsReachable(const Node * node)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