Allocate OverlapMapContainers in vector rather than on stack with copy

Allocate OverlapMapContainers in vector rather than on stack with copy

Currently, when we call beginNewOverlapTestingContext(), we create a
new OverlapMapContainers object on the stack, and copy it into the
vector. This performs an unnecessary copy of a moderately sized object
(~2KB), as well as using up stack space, which can be problematic due
to aggressive inlining.

This change uses the Vector's grow function, rather than append. This
prevents the stack allocation and the copy.

R=chrishtr
BUG=660097
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2

Committed: https://crrev.com/3113a826ff6fcc0e2dcc5db52c937457a31bbc95
Cr-Commit-Position: refs/heads/master@{#429999}

[ericrk, 2016-11-03 18:04:24]

Description was changed from

==========
Allocate OverlapMapContainers in vector rather than on stack with copy

Currently, when we call beginNewOverlapTestingContext(), we create a
new OverlapMapContainers object on the stack, and copy it into the
vector. This performs an unnecessary copy of a moderately sized object
(~2KB), as well as using up stack space, which can be problematic due
to aggressive inlining.

This change uses the Vector's grow function, rather than append. This
prevents the stack allocation and the copy.

R=chrishtr
BUG=660097
==========

to

==========
Allocate OverlapMapContainers in vector rather than on stack with copy

Currently, when we call beginNewOverlapTestingContext(), we create a
new OverlapMapContainers object on the stack, and copy it into the
vector. This performs an unnecessary copy of a moderately sized object
(~2KB), as well as using up stack space, which can be problematic due
to aggressive inlining.

This change uses the Vector's grow function, rather than append. This
prevents the stack allocation and the copy.

R=chrishtr
BUG=660097
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
==========

[ericrk, 2016-11-03 18:05:27]

The CQ bit was checked by ericrk@chromium.org

[ericrk, 2016-11-03 18:05:28]

The CQ bit was unchecked by ericrk@chromium.org

[ericrk, 2016-11-03 18:05:31]

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

[commit-bot: I haz the power, 2016-11-03 18:06:05]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[chrishtr, 2016-11-03 18:13:58]

lgtm

[chrishtr, 2016-11-03 18:14:07]

The CQ bit was unchecked by chrishtr@chromium.org

[chrishtr, 2016-11-03 18:14:09]

The CQ bit was checked by chrishtr@chromium.org

[commit-bot: I haz the power, 2016-11-03 18:14:19]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-11-03 22:12:20]

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

[commit-bot: I haz the power, 2016-11-03 22:12:22]

Try jobs failed on following builders:
  win_chromium_x64_rel_ng on master.tryserver.chromium.win (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.win/builders/win_chromium_x64_...)

[chrishtr, 2016-11-03 22:14:42]

The CQ bit was checked by chrishtr@chromium.org

[commit-bot: I haz the power, 2016-11-03 22:15:48]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-11-04 03:19:06]

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

[commit-bot: I haz the power, 2016-11-04 03:19:06]

Try jobs failed on following builders:
  win_chromium_x64_rel_ng on master.tryserver.chromium.win (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.win/builders/win_chromium_x64_...)

[chrishtr, 2016-11-04 18:03:52]

The CQ bit was checked by chrishtr@chromium.org

[commit-bot: I haz the power, 2016-11-04 18:04:31]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-11-04 20:23:44]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-11-04 20:27:08]

Description was changed from

==========
Allocate OverlapMapContainers in vector rather than on stack with copy

Currently, when we call beginNewOverlapTestingContext(), we create a
new OverlapMapContainers object on the stack, and copy it into the
vector. This performs an unnecessary copy of a moderately sized object
(~2KB), as well as using up stack space, which can be problematic due
to aggressive inlining.

This change uses the Vector's grow function, rather than append. This
prevents the stack allocation and the copy.

R=chrishtr
BUG=660097
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
==========

to

==========
Allocate OverlapMapContainers in vector rather than on stack with copy

Currently, when we call beginNewOverlapTestingContext(), we create a
new OverlapMapContainers object on the stack, and copy it into the
vector. This performs an unnecessary copy of a moderately sized object
(~2KB), as well as using up stack space, which can be problematic due
to aggressive inlining.

This change uses the Vector's grow function, rather than append. This
prevents the stack allocation and the copy.

R=chrishtr
BUG=660097
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2

Committed: https://crrev.com/3113a826ff6fcc0e2dcc5db52c937457a31bbc95
Cr-Commit-Position: refs/heads/master@{#429999}
==========

[commit-bot: I haz the power, 2016-11-04 20:27:10]

Patchset 1 (id:??) landed as
https://crrev.com/3113a826ff6fcc0e2dcc5db52c937457a31bbc95
Cr-Commit-Position: refs/heads/master@{#429999}