Replaced a bailout ID assertion with quadratic time complexity by a linear one.

src/data-flow.h

Index: src/data-flow.h
diff --git a/src/data-flow.h b/src/data-flow.h
index 71f56e718b92861cfff2f3ad08814f2d39b7d39f..268f21e127e12629cec29aefafe73f91ee14b054 100644
--- a/src/data-flow.h
+++ b/src/data-flow.h
@@ -199,6 +199,40 @@ class BitVector: public ZoneObject {
   uint32_t* data_;
 };
 
+class GrowableBitVector BASE_EMBEDDED {
+ public:
+  GrowableBitVector() : bits_(NULL) { }
+
+  bool Contains(int value) const {
+    if (!InBitsRange(value)) return false;
+    return bits_->Contains(value);
+  }
+
+  void Add(int value, Zone* zone) {
+    EnsureCapacity(value, zone);
+    bits_->Add(value);
+  }
+
+ private:
+  static const int kInitialLength = 1024;
+
+  bool InBitsRange(int value) const {
+    return bits_ != NULL && bits_->length() > value;
+  }
+
+  void EnsureCapacity(int value, Zone* zone) {
+    if (InBitsRange(value)) return;
+    int new_length = bits_ == NULL ? kInitialLength : bits_->length();
+    while (new_length <= value) new_length *= 2;
+    BitVector* new_bits = new(zone) BitVector(new_length, zone);
+    if (bits_ != NULL) new_bits->CopyFrom(*bits_);
+    bits_ = new_bits;
+  }
+
+  BitVector* bits_;
+};
+
+
 } }  // namespace v8::internal