Removing a wrong check....

src/objects.cc

Index: src/objects.cc
===================================================================
--- src/objects.cc	(revision 5369)
+++ src/objects.cc	(working copy)
@@ -4990,17 +4990,20 @@
 }
 
 
-uint32_t StringHasher::MakeCachedArrayIndex(uint32_t value, int length) {
-  value <<= String::kHashShift;
+uint32_t StringHasher::MakeArrayIndexHash(uint32_t value, int length) {
   // For array indexes mix the length into the hash as an array index could
   // be zero.
   ASSERT(length > 0);
   ASSERT(length <= String::kMaxArrayIndexSize);
   ASSERT(TenToThe(String::kMaxCachedArrayIndexLength) <
          (1 << String::kArrayIndexValueBits));
-  ASSERT(String::kMaxArrayIndexSize < (1 << String::kArrayIndexValueBits));
-  value &= ~String::kIsNotArrayIndexMask;
+
+  value <<= String::kHashShift;
   value |= length << String::kArrayIndexHashLengthShift;
+
+  ASSERT((value & String::kIsNotArrayIndexMask) == 0);
+  ASSERT((length > String::kMaxCachedArrayIndexLength) ||
+         (value & String::kContainsCachedArrayIndexMask) == 0);
   return value;
 }
 
@@ -5009,7 +5012,7 @@
   ASSERT(is_valid());
   if (length_ <= String::kMaxHashCalcLength) {
     if (is_array_index()) {
-      return MakeCachedArrayIndex(array_index(), length_);
+      return MakeArrayIndexHash(array_index(), length_);
     }
     return (GetHash() << String::kHashShift) | String::kIsNotArrayIndexMask;
   } else {