LayoutDescriptorHelper is now able to calculate the length of contiguous regions of tagged/non-tagg…

LayoutDescriptorHelper is now able to calculate the length of contiguous regions of tagged/non-tagged fields.
This functionality is now used by both object visitor and store buffer.

TEST=cctest/test-unboxed-doubles

Committed: https://crrev.com/b74cfe4a8f58dc87a7f9620e3075b558785eb020
Cr-Commit-Position: refs/heads/master@{#25816}

[Igor Sheludko, 2014-11-14 09:56:34]

Patchset #1 (id:1) has been deleted

[Igor Sheludko, 2014-11-14 10:01:21]

ishell@chromium.org changed reviewers:
+ hpayer@chromium.org

[Igor Sheludko, 2014-11-14 10:01:22]

PTAL (no hurry, I'm planning to land this after double unboxing is enabled)

[Hannes Payer (out of office), 2014-11-25 17:20:13]

LGTM, with a few nits.

https://codereview.chromium.org/726713003/diff/40001/src/heap/objects-visiting.h
File src/heap/objects-visiting.h (right):

https://codereview.chromium.org/726713003/diff/40001/src/heap/objects-visitin...
src/heap/objects-visiting.h:236: DCHECK(offset < end_of_region_offset);
I think that DCHECK should be in the IsTagged function.

https://codereview.chromium.org/726713003/diff/40001/src/heap/store-buffer.cc
File src/heap/store-buffer.cc (right):

https://codereview.chromium.org/726713003/diff/40001/src/heap/store-buffer.cc...
src/heap/store-buffer.cc:529: DCHECK(offset < end_of_region_offset);
I think that DCHECK should be in the IsTagged function.

https://codereview.chromium.org/726713003/diff/40001/src/layout-descriptor.cc
File src/layout-descriptor.cc (right):

https://codereview.chromium.org/726713003/diff/40001/src/layout-descriptor.cc...
src/layout-descriptor.cc:149: int ntz32(uint32_t x) {
Can we move this to utils or some global place that makes sense.

https://codereview.chromium.org/726713003/diff/40001/src/layout-descriptor.h
File src/layout-descriptor.h (right):

https://codereview.chromium.org/726713003/diff/40001/src/layout-descriptor.h#...
src/layout-descriptor.h:30: // Returns true if given field is tagged or false
otherwise and writes the
... the given fields are ...

https://codereview.chromium.org/726713003/diff/40001/src/layout-descriptor.h#...
src/layout-descriptor.h:126: // Returns true if field at |offset_in_bytes| is
tagged or false otherwise
... fields starting at |offset_in_bytes| are tagged ...

[Igor Sheludko, 2014-12-10 18:20:59]

Patchset #4 (id:80001) has been deleted

[Igor Sheludko, 2014-12-10 18:22:05]

Addressed comments and rebased.

https://codereview.chromium.org/726713003/diff/40001/src/heap/objects-visiting.h
File src/heap/objects-visiting.h (right):

https://codereview.chromium.org/726713003/diff/40001/src/heap/objects-visitin...
src/heap/objects-visiting.h:236: DCHECK(offset < end_of_region_offset);
On 2014/11/25 17:20:13, Hannes Payer wrote:
> I think that DCHECK should be in the IsTagged function.

Done.

https://codereview.chromium.org/726713003/diff/40001/src/heap/store-buffer.cc
File src/heap/store-buffer.cc (right):

https://codereview.chromium.org/726713003/diff/40001/src/heap/store-buffer.cc...
src/heap/store-buffer.cc:529: DCHECK(offset < end_of_region_offset);
On 2014/11/25 17:20:13, Hannes Payer wrote:
> I think that DCHECK should be in the IsTagged function.

Done.

https://codereview.chromium.org/726713003/diff/40001/src/layout-descriptor.cc
File src/layout-descriptor.cc (right):

https://codereview.chromium.org/726713003/diff/40001/src/layout-descriptor.cc...
src/layout-descriptor.cc:149: int ntz32(uint32_t x) {
On 2014/11/25 17:20:13, Hannes Payer wrote:
> Can we move this to utils or some global place that makes sense.

I removed it in favor of v8::base::bits::CountTrailingZeros32().

https://codereview.chromium.org/726713003/diff/40001/src/layout-descriptor.h
File src/layout-descriptor.h (right):

https://codereview.chromium.org/726713003/diff/40001/src/layout-descriptor.h#...
src/layout-descriptor.h:30: // Returns true if given field is tagged or false
otherwise and writes the
On 2014/11/25 17:20:13, Hannes Payer wrote:
> ... the given fields are ...

Done.

https://codereview.chromium.org/726713003/diff/40001/src/layout-descriptor.h#...
src/layout-descriptor.h:126: // Returns true if field at |offset_in_bytes| is
tagged or false otherwise
On 2014/11/25 17:20:13, Hannes Payer wrote:
> ... fields starting at |offset_in_bytes| are tagged ...

Done.

https://codereview.chromium.org/726713003/diff/100001/src/heap/heap.cc
File src/heap/heap.cc (right):

https://codereview.chromium.org/726713003/diff/100001/src/heap/heap.cc#newcod...
src/heap/heap.cc:1815: LayoutDescriptorHelper helper(target->map());
This is a new set of changes that was not included in the first patch set.

[Igor Sheludko, 2014-12-15 10:58:16]

The CQ bit was checked by ishell@chromium.org

[commit-bot: I haz the power, 2014-12-15 10:59:07]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/726713003/100001

[commit-bot: I haz the power, 2014-12-15 11:04:36]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2014-12-15 11:04:37]

Try jobs failed on following builders:
  v8_linux64_rel on tryserver.v8
(http://build.chromium.org/p/tryserver.v8/builders/v8_linux64_rel/builds/1857)
  v8_linux_arm64_rel on tryserver.v8
(http://build.chromium.org/p/tryserver.v8/builders/v8_linux_arm64_rel/builds/1760)

[Igor Sheludko, 2014-12-15 11:45:32]

The CQ bit was checked by ishell@chromium.org

[commit-bot: I haz the power, 2014-12-15 11:46:14]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/726713003/120001

[commit-bot: I haz the power, 2014-12-15 12:13:15]

Committed patchset #5 (id:120001)

[commit-bot: I haz the power, 2014-12-17 10:13:16]

Patchset 5 (id:??) landed as
https://crrev.com/b74cfe4a8f58dc87a7f9620e3075b558785eb020
Cr-Commit-Position: refs/heads/master@{#25816}