[stubs] Improve code generation for ToBoolean.

[stubs] Improve code generation for ToBoolean.

Introduce a proper CodeStubAssembler::BranchIfToBooleanIsTrue helper
method, that branches to if_true/if_false labels depending on whether
the value that is passed would yield true or false when fed to
ToBoolean. Use this helper to implement the bytecode handlers w/o having
to materialize the temporary booleans and essentially branching twice.
The CodeStubAssembler::BranchIfToBooleanIsTrue helper favors the most
likely case of a Boolean constant now.

Also migrate the ToBooleanStub to a ToBoolean TurboFan builtin, that
also uses the helper method under the hood.

Remove the now obsolete Oddball::to_boolean field.

R=hpayer@chromium.org, rmcilroy@chromium.org, yangguo@chromium.org

Committed: https://crrev.com/0abba43524eb618ae9733a28d424b395722ea33b
Cr-Commit-Position: refs/heads/master@{#37849}

[Benedikt Meurer, 2016-07-15 05:07:31]

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

[commit-bot: I haz the power, 2016-07-15 05:07:41]

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

[Benedikt Meurer, 2016-07-15 05:08:29]

bmeurer@chromium.org changed reviewers:
+ ulan@chromium.org

[Benedikt Meurer, 2016-07-15 05:08:30]

Yang: PTAL overall.
Ross: PTAL at interpreter and overall.
Hannes/Ulan: Please rubberstamp heap.cc

[Benedikt Meurer, 2016-07-15 05:21:29]

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

[commit-bot: I haz the power, 2016-07-15 05:21:31]

Dry run: 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, 2016-07-15 05:45:00]

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

[commit-bot: I haz the power, 2016-07-15 05:45:01]

Dry run: Try jobs failed on following builders:
  v8_linux_dbg_ng on master.tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux_dbg_ng/builds/9117)
  v8_linux_dbg_ng_triggered on master.tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux_dbg_ng_triggered/b...)

[ulan, 2016-07-15 09:41:33]

heap lgtm

[rmcilroy, 2016-07-15 09:44:33]

Nice, LGTM (modulo red bots). Thanks!

[Yang, 2016-07-15 11:24:42]

On 2016/07/15 09:44:33, rmcilroy wrote:
> Nice, LGTM (modulo red bots). Thanks!

LGTM

[Benedikt Meurer, 2016-07-19 05:32:32]

The CQ bit was checked by bmeurer@chromium.org

[Benedikt Meurer, 2016-07-19 05:32:32]

The patchset sent to the CQ was uploaded after l-g-t-m from ulan@chromium.org,
rmcilroy@chromium.org, yangguo@chromium.org
Link to the patchset: https://codereview.chromium.org/2151163002/#ps40001
(title: "REBASE. Fix redness.")

[commit-bot: I haz the power, 2016-07-19 05:32:38]

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, 2016-07-19 06:13:41]

Committed patchset #3 (id:40001)

[commit-bot: I haz the power, 2016-07-19 06:16:24]

Description was changed from

==========
[stubs] Improve code generation for ToBoolean.

Introduce a proper CodeStubAssembler::BranchIfToBooleanIsTrue helper
method, that branches to if_true/if_false labels depending on whether
the value that is passed would yield true or false when fed to
ToBoolean. Use this helper to implement the bytecode handlers w/o having
to materialize the temporary booleans and essentially branching twice.
The CodeStubAssembler::BranchIfToBooleanIsTrue helper favors the most
likely case of a Boolean constant now.

Also migrate the ToBooleanStub to a ToBoolean TurboFan builtin, that
also uses the helper method under the hood.

Remove the now obsolete Oddball::to_boolean field.

R=hpayer@chromium.org, rmcilroy@chromium.org, yangguo@chromium.org
==========

to

==========
[stubs] Improve code generation for ToBoolean.

Introduce a proper CodeStubAssembler::BranchIfToBooleanIsTrue helper
method, that branches to if_true/if_false labels depending on whether
the value that is passed would yield true or false when fed to
ToBoolean. Use this helper to implement the bytecode handlers w/o having
to materialize the temporary booleans and essentially branching twice.
The CodeStubAssembler::BranchIfToBooleanIsTrue helper favors the most
likely case of a Boolean constant now.

Also migrate the ToBooleanStub to a ToBoolean TurboFan builtin, that
also uses the helper method under the hood.

Remove the now obsolete Oddball::to_boolean field.

R=hpayer@chromium.org, rmcilroy@chromium.org, yangguo@chromium.org

Committed: https://crrev.com/0abba43524eb618ae9733a28d424b395722ea33b
Cr-Commit-Position: refs/heads/master@{#37849}
==========

[commit-bot: I haz the power, 2016-07-19 06:16:25]

Patchset 3 (id:??) landed as
https://crrev.com/0abba43524eb618ae9733a28d424b395722ea33b
Cr-Commit-Position: refs/heads/master@{#37849}