[ignition] Add bytecodes for loads/stores in the current context

[ignition] Add bytecodes for loads/stores in the current context

The majority of context slot accesses are to the local context (current context
register and depth 0), so this adds bytecodes to optimise for that case.

This cuts down bytecode size by roughly 1% (measured on Octane and Top25).

Committed: https://crrev.com/d2caa302a7bc8cd54dbfaf4e4cfbb3fb81ada378
Cr-Commit-Position: refs/heads/master@{#40641}

[Leszek Swirski, 2016-10-27 10:50:10]

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

[commit-bot: I haz the power, 2016-10-27 10:50:19]

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, 2016-10-27 11:16:00]

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

[commit-bot: I haz the power, 2016-10-27 11:16:01]

Dry run: This issue passed the CQ dry run.

[Leszek Swirski, 2016-10-27 11:17:32]

leszeks@chromium.org changed reviewers:
+ mstarzinger@chromium.org, rmcilroy@chromium.org

[Leszek Swirski, 2016-10-27 11:17:33]

rmcilroy@chromium.org: Please review changes in interpreter & tests

mstarzinger@chromium.org: Please review changes in bytecode graph builder

[Michael Starzinger, 2016-10-27 12:21:26]

LGTM from my end.

https://codereview.chromium.org/2459513002/diff/1/src/interpreter/interpreter.h
File src/interpreter/interpreter.h (right):

https://codereview.chromium.org/2459513002/diff/1/src/interpreter/interpreter...
src/interpreter/interpreter.h:145: // Generates code to load a local context
slot.
nit: s/"local context slot"/"context slot in the current context"/

[rmcilroy, 2016-10-27 13:44:09]

LGTM

https://codereview.chromium.org/2459513002/diff/1/src/compiler/bytecode-graph...
File src/compiler/bytecode-graph-builder.h (right):

https://codereview.chromium.org/2459513002/diff/1/src/compiler/bytecode-graph...
src/compiler/bytecode-graph-builder.h:138: Node* BuildLoadLocalContextSlot();
Could we call this CurrentContext instead (throughout) - local context is a bit
overloaded (it could mean the function local context, which isn't always the
same as the current context).

https://codereview.chromium.org/2459513002/diff/1/test/unittests/interpreter/...
File test/unittests/interpreter/bytecode-array-builder-unittest.cc (right):

https://codereview.chromium.org/2459513002/diff/1/test/unittests/interpreter/...
test/unittests/interpreter/bytecode-array-builder-unittest.cc:405:
scorecard[Bytecodes::ToByte(Bytecode::kShiftRightSmi)] = 1;
Could you add it here too (so that this test still passes if
--no-ignition_peephole is set).

[Leszek Swirski, 2016-10-28 09:44:08]

The CQ bit was checked by leszeks@chromium.org

[Leszek Swirski, 2016-10-28 09:44:08]

The patchset sent to the CQ was uploaded after l-g-t-m from
rmcilroy@chromium.org, mstarzinger@chromium.org
Link to the patchset: https://codereview.chromium.org/2459513002/#ps20001
(title: "s/LocalContext/CurrentContext/g")

[commit-bot: I haz the power, 2016-10-28 09:44:14]

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, 2016-10-28 10:10:40]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2016-11-17 22:16:33]

Description was changed from

==========
[ignition] Add bytecodes for loads/stores in the current context

The majority of context slot accesses are to the local context (current context
register and depth 0), so this adds bytecodes to optimise for that case.

This cuts down bytecode size by roughly 1% (measured on Octane and Top25).
==========

to

==========
[ignition] Add bytecodes for loads/stores in the current context

The majority of context slot accesses are to the local context (current context
register and depth 0), so this adds bytecodes to optimise for that case.

This cuts down bytecode size by roughly 1% (measured on Octane and Top25).

Committed: https://crrev.com/d2caa302a7bc8cd54dbfaf4e4cfbb3fb81ada378
Cr-Commit-Position: refs/heads/master@{#40641}
==========

[commit-bot: I haz the power, 2016-11-17 22:16:35]

Patchset 2 (id:??) landed as
https://crrev.com/d2caa302a7bc8cd54dbfaf4e4cfbb3fb81ada378
Cr-Commit-Position: refs/heads/master@{#40641}