Don't use ConsStringIterator to compute string hashes

src/objects.cc

Index: src/objects.cc
diff --git a/src/objects.cc b/src/objects.cc
index 5262ed65671afa93c941173f9124813ab82c56ab..7900ef3bcb35d2e5c405add63c43809b2c5ee27a 100644
--- a/src/objects.cc
+++ b/src/objects.cc
@@ -9283,6 +9283,20 @@ uint32_t StringHasher::ComputeUtf8Hash(Vector<const char> chars,
 }
 
 
+void IteratingStringHasher::VisitConsString(ConsString* cons_string) {
+  int length = cons_string->length();
+  uint16_t* buffer = cons_string->GetIsolate()->cons_string_hashing_buffer();
+  if (cons_string->HasOnlyOneByteChars()) {
+    uint8_t* one_byte_buffer = reinterpret_cast<uint8_t*>(buffer);
+    String::WriteToFlat(cons_string, one_byte_buffer, 0, length);

[Yang, 2014/11/26 10:46:15]

Wouldn't this cause OOB writes for large strings? I think what you want is
Min(length, String::kMaxHashCalcLength).

+    AddCharacters(one_byte_buffer, length);
+  } else {
+    String::WriteToFlat(cons_string, buffer, 0, length);
+    AddCharacters(buffer, length);
+  }
+}
+
+
 void String::PrintOn(FILE* file) {
   int length = this->length();
   for (int i = 0; i < length; i++) {