[turbofan] Fewer gap moves for tail calls

[turbofan] Fewer gap moves for tail calls

Restore frame pointer directly from stack rather than copying it and
restoring. Also restore return address register directly on platforms that
support it.

BUG=v8:4076
LOG=n

Committed: https://crrev.com/51e992f147b0f3c3763947655844915294de10e5
Cr-Commit-Position: refs/heads/master@{#32410}

[danno, 2015-11-30 13:39:12]

danno@chromium.org changed reviewers:
+ bmeurer@chromium.org, jarin@chromium.org

[danno, 2015-11-30 13:39:13]

PTAL

[Benedikt Meurer, 2015-11-30 14:33:46]

LGTM.

[danno, 2015-11-30 14:34:38]

The CQ bit was checked by danno@chromium.org

[commit-bot: I haz the power, 2015-11-30 14:34:43]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1488553002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1488553002/1

[commit-bot: I haz the power, 2015-11-30 14:42:13]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-11-30 14:42:21]

Description was changed from

==========
[turbofan] Fewer gap moves for tail calls

Restore frame pointer directly from stack rather than copying it and
restoring. Also restore return address register directly on platforms that
support it.

BUG=v8:4076
LOG=n
==========

to

==========
[turbofan] Fewer gap moves for tail calls

Restore frame pointer directly from stack rather than copying it and
restoring. Also restore return address register directly on platforms that
support it.

BUG=v8:4076
LOG=n

Committed: https://crrev.com/51e992f147b0f3c3763947655844915294de10e5
Cr-Commit-Position: refs/heads/master@{#32410}
==========

[commit-bot: I haz the power, 2015-11-30 14:42:22]

Patchset 1 (id:??) landed as
https://crrev.com/51e992f147b0f3c3763947655844915294de10e5
Cr-Commit-Position: refs/heads/master@{#32410}