Limit initial size of hidden properties and store identity hashes inline.

Limit initial size of hidden properties and store identity hashes inline.

BUG=v8:2211
TEST=test-heap/Regress2211

Committed: https://code.google.com/p/v8/source/detail?r=12230

[Yang, 2012-07-26 15:35:43]

PTAL. This supersedes https://chromiumcodereview.appspot.com/10824042/

[Yang, 2012-07-27 08:17:45]

On 2012/07/26 15:35:43, Yang wrote:
> PTAL. This supersedes https://chromiumcodereview.appspot.com/10824042/

Please take a look. Changes include:
- store identity hashes inline as smi when no backing store for hidden
properties is allocated
- use hash table as backing store for hidden properties
- force smaller initial capacity for the hash table for hidden properties
- change tests

[Toon Verwaest, 2012-07-30 09:13:23]

Added some comments.

https://chromiumcodereview.appspot.com/10827040/diff/2009/src/objects.cc
File src/objects.cc (right):

https://chromiumcodereview.appspot.com/10827040/diff/2009/src/objects.cc#newc...
src/objects.cc:3562: MaybeObject* hidden_lookup =
GetHiddenPropertiesHashTable(false);
Can we make an enum out of the bool argument?

https://chromiumcodereview.appspot.com/10827040/diff/2009/src/objects.cc#newc...
src/objects.cc:3575: if (hidden_lookup->ToObjectUnchecked()->IsUndefined()) {
Replace hidden_lookup->ToObjectUnchecked() by inline_value.

https://chromiumcodereview.appspot.com/10827040/diff/2009/src/objects.cc#newc...
src/objects.cc:3580: ObjectHashTable::cast(hidden_lookup->ToObjectUnchecked());
Replace hidden_lookup->ToObjectUnchecked() by inline_value.

https://chromiumcodereview.appspot.com/10827040/diff/2009/src/objects.cc#newc...
src/objects.cc:3581: Object* entry = hashtable->Lookup(key);
The API for hidden values does not convert strings as keys for hidden values to
symbols. The StringDictionary handles normal strings in addition to symbols,
while ObjectHashTable does not. We should probably convert all keys from the API
to symbols to ensure we don't break the API.

https://chromiumcodereview.appspot.com/10827040/diff/2009/src/objects.cc#newc...
src/objects.cc:3620: if (!hidden_lookup->To<ObjectHashTable>(&hashtable)) return
hidden_lookup;
You don't need the <ObjectHashTable> afaik.

https://chromiumcodereview.appspot.com/10827040/diff/2009/src/objects.cc#newc...
src/objects.cc:3625: if (!insert_result->To<ObjectHashTable>(&new_table)) return
insert_result;
Don't need the <ObjectHashTable>.

https://chromiumcodereview.appspot.com/10827040/diff/2009/src/objects.cc#newc...
src/objects.cc:3700: }
Please remove the { ... } around the MaybeObject. That's unnecessary; and we're
slowly removing it everywhere.

https://chromiumcodereview.appspot.com/10827040/diff/2009/src/objects.cc#newc...
src/objects.cc:3708: if (!insert_result->To<ObjectHashTable>(&new_table)) return
insert_result;
Remove the <ObjectHashTable>

https://chromiumcodereview.appspot.com/10827040/diff/2009/src/objects.cc#newc...
src/objects.cc:3725: Object* hidden) {
Can we rename hidden to hidden_properties or so? Put it on one line if it fits.

https://chromiumcodereview.appspot.com/10827040/diff/2009/src/objects.cc#newc...
src/objects.cc:11069: bool force_capacity,
Please use an enum.

https://chromiumcodereview.appspot.com/10827040/diff/2009/src/objects.cc#newc...
src/objects.cc:11182: Allocate(nof * 2, false, pretenure ? TENURED :
NOT_TENURED);
enum.

https://chromiumcodereview.appspot.com/10827040/diff/2009/src/objects.cc#newc...
src/objects.cc:11211: Allocate(at_least_room_for, false, pretenure ? TENURED :
NOT_TENURED);
enum.

https://chromiumcodereview.appspot.com/10827040/diff/2009/src/objects.h
File src/objects.h (right):

https://chromiumcodereview.appspot.com/10827040/diff/2009/src/objects.h#newco...
src/objects.h:2802: bool force_capacity = false,
Can this be an enum?

[Toon Verwaest, 2012-07-30 12:42:59]

lgtm