Add ScheduleVerifier.

src/data-flow.h

 // Copyright 2012 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_DATAFLOW_H_
 #define V8_DATAFLOW_H_
 
 #include "src/v8.h"
 
 #include "src/allocation.h"
@@ skipping 119 matching lines @@
     return changed;
   }
 
   void Intersect(const BitVector& other) {
     DCHECK(other.length() == length());
     for (int i = 0; i < data_length_; i++) {
       data_[i] &= other.data_[i];
     }
   }
 
+  bool IntersectIsChanged(const BitVector& other) {
+    DCHECK(other.length() == length());
+    bool changed = false;
+    for (int i = 0; i < data_length_; i++) {
+      uint32_t old_data = data_[i];
+      data_[i] &= other.data_[i];
+      if (data_[i] != old_data) changed = true;
+    }
+    return changed;
+  }
+
   void Subtract(const BitVector& other) {
     DCHECK(other.length() == length());
     for (int i = 0; i < data_length_; i++) {
       data_[i] &= ~other.data_[i];
     }
   }
 
   void Clear() {
     for (int i = 0; i < data_length_; i++) {
       data_[i] = 0;
@@ skipping 82 matching lines @@
     bits_ = new_bits;
   }
 
   BitVector* bits_;
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_DATAFLOW_H_