Exclude the bit-field bits from string hash codes. String hash codes...

src/objects-inl.h

 // Copyright 2006-2008 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 466 matching lines @@
 
 #define WRITE_DOUBLE_FIELD(p, offset, value) \
   (*reinterpret_cast<double*>(FIELD_ADDR(p, offset)) = value)
 
 #define READ_INT_FIELD(p, offset) \
   (*reinterpret_cast<int*>(FIELD_ADDR(p, offset)))
 
 #define WRITE_INT_FIELD(p, offset, value) \
   (*reinterpret_cast<int*>(FIELD_ADDR(p, offset)) = value)
 
+#define READ_UINT32_FIELD(p, offset) \
+  (*reinterpret_cast<uint32_t*>(FIELD_ADDR(p, offset)))
+
+#define WRITE_UINT32_FIELD(p, offset, value) \
+  (*reinterpret_cast<uint32_t*>(FIELD_ADDR(p, offset)) = value)
+
 #define READ_SHORT_FIELD(p, offset) \
   (*reinterpret_cast<uint16_t*>(FIELD_ADDR(p, offset)))
 
 #define WRITE_SHORT_FIELD(p, offset, value) \
   (*reinterpret_cast<uint16_t*>(FIELD_ADDR(p, offset)) = value)
 
 #define READ_BYTE_FIELD(p, offset) \
   (*reinterpret_cast<byte*>(FIELD_ADDR(p, offset)))
 
 #define WRITE_BYTE_FIELD(p, offset, value) \
@@ skipping 700 matching lines @@
     case kLongStringTag:
       WRITE_INT_FIELD(this, kLengthOffset, value << kLongLengthShift);
       break;
     default:
       UNREACHABLE();
       break;
   }
 }
 
 
-int String::length_field() {
-  return READ_INT_FIELD(this, kLengthOffset);
+uint32_t String::length_field() {
+  return READ_UINT32_FIELD(this, kLengthOffset);
 }
 
 
-void String::set_length_field(int value) {
-  WRITE_INT_FIELD(this, kLengthOffset, value);
+void String::set_length_field(uint32_t value) {
+  WRITE_UINT32_FIELD(this, kLengthOffset, value);
 }
 
 
 void String::TryFlatten() {
   // We don't need to flatten strings that are already flat.  Since this code
   // is inlined, it can be helpful in the flat case to not call out to Flatten.
   StringRepresentationTag str_type = representation_tag();
   if (str_type != kSeqStringTag && str_type != kExternalStringTag) {
     Flatten();
   }
@@ skipping 839 matching lines @@
 }
 
 
 bool String::HasHashCode() {
   return (length_field() & kHashComputedMask) != 0;
 }
 
 
 uint32_t String::Hash() {
   // Fast case: has hash code already been computed?
-  int hash = length_field();
-  if (hash & kHashComputedMask) return hash;
+  uint32_t field = length_field();
+  if (field & kHashComputedMask) return field >> kHashShift;
   // Slow case: compute hash code and set it..
   return ComputeAndSetHash();
 }
 
 
 bool String::AsArrayIndex(uint32_t* index) {
-  int hash = length_field();
-  if ((hash & kHashComputedMask) && !(hash & kIsArrayIndexMask)) return false;
+  uint32_t field = length_field();
+  if ((field & kHashComputedMask) && !(field & kIsArrayIndexMask)) return false;
   return SlowAsArrayIndex(index);
 }
 
 
 Object* JSObject::GetPrototype() {
   return JSObject::cast(this)->map()->prototype();
 }
 
 
 PropertyAttributes JSObject::GetPropertyAttribute(String* key) {
@@ skipping 75 matching lines @@
 #undef WRITE_INT_FIELD
 #undef READ_SHORT_FIELD
 #undef WRITE_SHORT_FIELD
 #undef READ_BYTE_FIELD
 #undef WRITE_BYTE_FIELD
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_INL_H_