Fast path for symbol lookup in JSON.parse.

src/objects.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 7367 matching lines @@
 
 void StringHasher::AddSurrogatePairNoIndex(uc32 c) {
   uint16_t lead = unibrow::Utf16::LeadSurrogate(c);
   AddCharacterNoIndex(lead);
   uint16_t trail = unibrow::Utf16::TrailSurrogate(c);
   AddCharacterNoIndex(trail);
 }
 
 
 uint32_t StringHasher::GetHashField() {
-  ASSERT(is_valid());
   if (length_ <= String::kMaxHashCalcLength) {
     if (is_array_index()) {
       return MakeArrayIndexHash(array_index(), length_);
     }
     return (GetHash() << String::kHashShift) | String::kIsNotArrayIndexMask;
   } else {
     return (length_ << String::kHashShift) | String::kIsNotArrayIndexMask;
   }
 }
 
@@ skipping 6147 matching lines @@
   set_year(Smi::FromInt(year), SKIP_WRITE_BARRIER);
   set_month(Smi::FromInt(month), SKIP_WRITE_BARRIER);
   set_day(Smi::FromInt(day), SKIP_WRITE_BARRIER);
   set_weekday(Smi::FromInt(weekday), SKIP_WRITE_BARRIER);
   set_hour(Smi::FromInt(hour), SKIP_WRITE_BARRIER);
   set_min(Smi::FromInt(min), SKIP_WRITE_BARRIER);
   set_sec(Smi::FromInt(sec), SKIP_WRITE_BARRIER);
 }
 
 } }  // namespace v8::internal