Home | History | Annotate | Download | only in blink_gc_plugin 
      1 // Copyright 2014 The Chromium 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 // NeedsTracing is a three-point value ordered by unneeded < unknown < needed.
      6 // Unneeded means that the point definitively does not need to be traced.
      7 
      8 #ifndef TOOLS_BLINK_GC_PLUGIN_NEEDS_TRACING_H_
      9 #define TOOLS_BLINK_GC_PLUGIN_NEEDS_TRACING_H_
     10 
     11 class NeedsTracing {
     12  public:
     13   static NeedsTracing Unneeded() { return kUnneeded; }
     14   static NeedsTracing Unknown() { return kUnknown; }
     15   static NeedsTracing Needed() { return kNeeded; }
     16   bool IsUnneeded() { return value_ == kUnneeded; }
     17   bool IsUnknown() { return value_ == kUnknown; }
     18   bool IsNeeded() { return value_ == kNeeded; }
     19   NeedsTracing LUB(const NeedsTracing& other) {
     20     return value_ > other.value_ ? value_ : other.value_;
     21   }
     22   bool operator==(const NeedsTracing& other) {
     23     return value_ == other.value_;
     24   }
     25  private:
     26   enum Value { kUnneeded, kUnknown, kNeeded };
     27   NeedsTracing(Value value) : value_(value) {}
     28   Value value_;
     29 };
     30 
     31 #endif // TOOLS_BLINK_GC_PLUGIN_NEEDS_TRACING_H_
     32