Don't allocate handles for substrings when filling up the split result array.

src/runtime.cc

 // Copyright 2011 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 5787 matching lines @@
   ASSERT(result->HasFastElements());
 
   if (part_count == 1 && indices.at(0) == subject_length) {
     FixedArray::cast(result->elements())->set(0, *subject);
     return *result;
   }
 
   Handle<FixedArray> elements(FixedArray::cast(result->elements()));
   int part_start = 0;
   for (int i = 0; i < part_count; i++) {
-    HandleScope local_loop_handle;
     int part_end = indices.at(i);
-    Handle<String> substring =
-        isolate->factory()->NewSubString(subject, part_start, part_end);
-    elements->set(i, *substring);
+    Object* result;
+    { MaybeObject* maybe_result = isolate->heap()->AllocateSubString(*subject,
+                                                                     part_start,

[Lasse Reichstein, 2011/06/10 07:32:17]

This is an unpretty combination of handle and non-handle code.
Make the JSArray and FixedArray allocations not use handles either, and remove
the HandleScope.

Perhaps don't allocate the JSArray until the end.

[sandholm, 2011/06/10 10:13:31]

Done.

+                                                                     part_end);
+      if (!maybe_result->ToObject(&result)) return maybe_result;
+    }
+    elements->set(i, result);
     part_start = part_end + pattern_length;
   }
 
   return *result;
 }
 
 
 // Copies ascii characters to the given fixed array looking up
 // one-char strings in the cache. Gives up on the first char that is
 // not in the cache and fills the remainder with smi zeros. Returns
@@ skipping 6540 matching lines @@
   } else {
     // Handle last resort GC and make sure to allow future allocations
     // to grow the heap without causing GCs (if possible).
     isolate->counters()->gc_last_resort_from_js()->Increment();
     isolate->heap()->CollectAllGarbage(false);
   }
 }
 
 
 } }  // namespace v8::internal