[turbofan] Fix accumulator use in bytecode analysis.

[turbofan] Fix accumulator use in bytecode analysis.

This fixes the checks of accumulator usage flags in the computation of
the interpreter register liveness during bytecode analysis. The usage
flags at hand are bit patterns as opposed to flat enum values. Use the
safe accessors instead of plain comparison.

R=jarin@chromium.org
TEST=mjsunit/regress/regress-crbug-683581
BUG=chromium:683581
Review-Url: https://codereview.chromium.org/2651653005
Cr-Commit-Position: refs/heads/master@{#42648}
Committed: https://chromium.googlesource.com/v8/v8/+/efc8cb16d783c923c690be93cd55ae37f947edca

[Michael Starzinger, 2017-01-24 12:32:56]

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

[commit-bot: I haz the power, 2017-01-24 12:33:01]

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

[Michael Starzinger, 2017-01-24 13:02:19]

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

[Michael Starzinger, 2017-01-24 13:02:19]

Jaro: PTAL.
Leszek: FYI.

[commit-bot: I haz the power, 2017-01-24 13:23:39]

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

[commit-bot: I haz the power, 2017-01-24 13:23:40]

Dry run: This issue passed the CQ dry run.

[rmcilroy, 2017-01-24 14:41:49]

Yikes, good catch thanks Michi. LGTM FWIW.

[Leszek Swirski, 2017-01-24 19:58:23]

Thanks Michi, I thought that I'd thought of this (since the other option is
kReadWrite) but clearly I didn't think hard enough.

https://codereview.chromium.org/2651653005/diff/1/src/compiler/bytecode-analy...
File src/compiler/bytecode-analysis.cc (right):

https://codereview.chromium.org/2651653005/diff/1/src/compiler/bytecode-analy...
src/compiler/bytecode-analysis.cc:140: if
(Bytecodes::ReadsAccumulator(bytecode)) {
This is probably better for readability's sake, but if we wanted to be
completely optimal we could skip marking the accumulator as dead and just set
this if kRead or kReadWrite.

[Jarin, 2017-01-25 06:48:53]

lgtm, thanks!

[Michael Starzinger, 2017-01-25 09:12:38]

The CQ bit was checked by mstarzinger@chromium.org

[commit-bot: I haz the power, 2017-01-25 09:12:42]

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, 2017-01-25 09:14:41]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1485335558777880, "parent_rev":
"d0a24e913f6653531786bc237793fdb0e7ebfa53", "commit_rev":
"efc8cb16d783c923c690be93cd55ae37f947edca"}

[commit-bot: I haz the power, 2017-01-25 09:14:45]

Description was changed from

==========
[turbofan] Fix accumulator use in bytecode analysis.

This fixes the checks of accumulator usage flags in the computation of
the interpreter register liveness during bytecode analysis. The usage
flags at hand are bit patterns as opposed to flat enum values. Use the
safe accessors instead of plain comparison.

R=jarin@chromium.org
TEST=mjsunit/regress/regress-crbug-683581
BUG=chromium:683581
==========

to

==========
[turbofan] Fix accumulator use in bytecode analysis.

This fixes the checks of accumulator usage flags in the computation of
the interpreter register liveness during bytecode analysis. The usage
flags at hand are bit patterns as opposed to flat enum values. Use the
safe accessors instead of plain comparison.

R=jarin@chromium.org
TEST=mjsunit/regress/regress-crbug-683581
BUG=chromium:683581

Review-Url: https://codereview.chromium.org/2651653005
Cr-Commit-Position: refs/heads/master@{#42648}
Committed:
https://chromium.googlesource.com/v8/v8/+/efc8cb16d783c923c690be93cd55ae37f94...
==========

[commit-bot: I haz the power, 2017-01-25 09:14:46]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/v8/v8/+/efc8cb16d783c923c690be93cd55ae37f94...