PPC: [interpreter] Add Interpreter{Entry,Exit}Trampoline builtins. Port c5dd553cf3a44cd8c17958a5951…

PPC: [interpreter] Add Interpreter{Entry,Exit}Trampoline builtins.

Port c5dd553cf3a44cd8c17958a595198b5ea9492cd0

Original commit message:
    Adds interpreter entry and exit trampoline builtins. Also implements the
    Return bytecode handler and fixes a few bugs in InterpreterAssembler
    highlighted by running on other architectures.

R=rmcilroy@chromium.org, michael_dawson@ca.ibm.com, jyan@ca.ibm.com, joransiu@ca.ibm.com
BUG=v8:4280
LOG=N

Committed: https://crrev.com/0ea4e6d50de8752713dbfe18588f05400796e584
Cr-Commit-Position: refs/heads/master@{#29939}

[john.yan, 2015-07-30 18:05:06]

lgtm

[MTBrandyberry, 2015-07-30 18:08:14]

The CQ bit was checked by mbrandy@us.ibm.com

[commit-bot: I haz the power, 2015-07-30 18:08:28]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1266053002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1266053002/1

[commit-bot: I haz the power, 2015-07-30 18:08:28]

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

[commit-bot: I haz the power, 2015-07-30 18:08:29]

No L-G-T-M from a valid reviewer yet. Only full committers are accepted.
Even if an L-G-T-M may have been provided, it was from a non-committer,
_not_ a full super star committer.
See http://www.chromium.org/getting-involved/become-a-committer
Note that this has nothing to do with OWNERS files.

[michael_dawson, 2015-07-30 18:18:27]

On 2015/07/30 18:08:29, commit-bot: I haz the power wrote:
> No L-G-T-M from a valid reviewer yet. Only full committers are accepted.
> Even if an L-G-T-M may have been provided, it was from a non-committer,
> _not_ a full super star committer.
> See http://www.chromium.org/getting-involved/become-a-committer
> Note that this has nothing to do with OWNERS files.

lgtm

[MTBrandyberry, 2015-07-30 18:19:21]

The CQ bit was checked by mbrandy@us.ibm.com

[commit-bot: I haz the power, 2015-07-30 18:19:29]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1266053002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1266053002/1

[commit-bot: I haz the power, 2015-07-30 18:43:38]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-07-30 18:43:59]

Patchset 1 (id:??) landed as
https://crrev.com/0ea4e6d50de8752713dbfe18588f05400796e584
Cr-Commit-Position: refs/heads/master@{#29939}