[heap] Add compaction space.

[heap] Add compaction space.

The CompactionSpace is temporarily used during compaction to hold migrated
objects. The payload is merged back into the corresponding space after
compaction.

Note the this is not the complete implementation and it is currently only used in a test.

BUG=chromium:524425
LOG=N

Committed: https://crrev.com/147330f37c122a4b537c8b79b29521af6f760d92
Cr-Commit-Position: refs/heads/master@{#30407}

[Michael Lippautz, 2015-08-26 13:49:59]

Hej Hannes,

This is the initial CL we talked about. Will follow up with emergency memory and
initializing from some other free list chunk.

PTAL

https://codereview.chromium.org/1314493007/diff/20001/src/heap/spaces.h
File src/heap/spaces.h (left):

https://codereview.chromium.org/1314493007/diff/20001/src/heap/spaces.h#oldco...
src/heap/spaces.h:1713: void TearDown();
Let's remove one of the landmines and make TearDown() private and implicitly
called by the destructor (?)

https://codereview.chromium.org/1314493007/diff/20001/src/heap/spaces.h
File src/heap/spaces.h (right):

https://codereview.chromium.org/1314493007/diff/20001/src/heap/spaces.h#newco...
src/heap/spaces.h:1928: void CreateEmergencyMemory();
The plan is to move those to the compaction space (in some form) and remove it
here.

https://codereview.chromium.org/1314493007/diff/20001/src/heap/spaces.h#newco...
src/heap/spaces.h:1942: // Cleans up the space, frees all pages in this space
except those belonging
Just following decl order here.

https://codereview.chromium.org/1314493007/diff/20001/test/cctest/test-spaces.cc
File test/cctest/test-spaces.cc (right):

https://codereview.chromium.org/1314493007/diff/20001/test/cctest/test-spaces...
test/cctest/test-spaces.cc:344: // OldSpace's destructor will tear down the
space and free up all pages.
This is a result of hiding TearDown(). Furthermore the other tests in this file
properly set up TestMemoryAllocatorScope. This change merely adopts to the rest
of the file.

https://codereview.chromium.org/1314493007/diff/20001/test/cctest/test-spaces...
test/cctest/test-spaces.cc:401: TEST(CompactionSpace) {
Tests the page moving when the free list is empty. The followup will contain
logic for the free list and the emergency memory.

[Michael Lippautz, 2015-08-26 14:55:37]

The CQ bit was checked by mlippautz@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2015-08-26 14:55:49]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1314493007/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1314493007/20001

[commit-bot: I haz the power, 2015-08-26 15:05:31]

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

[commit-bot: I haz the power, 2015-08-26 15:05:31]

Dry run: Try jobs failed on following builders:
  v8_mac_rel on tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_mac_rel/builds/9102)

[Michael Lippautz, 2015-08-27 11:04:39]

PTAL, older comments still apply.

https://codereview.chromium.org/1314493007/diff/80001/src/heap/spaces.h
File src/heap/spaces.h (right):

https://codereview.chromium.org/1314493007/diff/80001/src/heap/spaces.h#newco...
src/heap/spaces.h:1942: virtual bool snapshotable() { return true; }
We could also make this a field in the space object and set it via constructor,
or some other lookup, or a macro..

[Hannes Payer (out of office), 2015-08-27 11:14:20]

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

[Hannes Payer (out of office), 2015-08-27 11:14:20]

LGTM

https://codereview.chromium.org/1314493007/diff/80001/src/heap/spaces.cc
File src/heap/spaces.cc (right):

https://codereview.chromium.org/1314493007/diff/80001/src/heap/spaces.cc#newc...
src/heap/spaces.cc:1004: void PagedSpace::MergeCompactionSpace(CompactionSpace*
other) {
Nice!

https://codereview.chromium.org/1314493007/diff/80001/test/cctest/test-spaces.cc
File test/cctest/test-spaces.cc (right):

https://codereview.chromium.org/1314493007/diff/80001/test/cctest/test-spaces...
test/cctest/test-spaces.cc:433: CHECK_LE(old_space->CountTotalPages(),
Shouldn't that be equal?

[Michael Lippautz, 2015-08-27 11:28:07]

https://codereview.chromium.org/1314493007/diff/80001/test/cctest/test-spaces.cc
File test/cctest/test-spaces.cc (right):

https://codereview.chromium.org/1314493007/diff/80001/test/cctest/test-spaces...
test/cctest/test-spaces.cc:433: CHECK_LE(old_space->CountTotalPages(),
On 2015/08/27 11:14:20, Hannes Payer wrote:
> Shouldn't that be equal?

Done.

[Michael Lippautz, 2015-08-27 11:29:36]

The CQ bit was checked by mlippautz@chromium.org

[Michael Lippautz, 2015-08-27 11:29:36]

The patchset sent to the CQ was uploaded after l-g-t-m from hpayer@chromium.org
Link to the patchset: https://codereview.chromium.org/1314493007/#ps120001
(title: "rebase")

[commit-bot: I haz the power, 2015-08-27 11:29:43]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1314493007/120001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1314493007/120001

[commit-bot: I haz the power, 2015-08-27 12:16:05]

Committed patchset #7 (id:120001)

[commit-bot: I haz the power, 2015-08-27 12:16:31]

Patchset 7 (id:??) landed as
https://crrev.com/147330f37c122a4b537c8b79b29521af6f760d92
Cr-Commit-Position: refs/heads/master@{#30407}