All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=609739

Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?keys=agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICgtIiXqQoM


Bot(s) for this bug's original alert(s):

Haswell_x64

The following revision refers to this bug:
  https://chromium.googlesource.com/v8/v8.git/+/f98caf44b80d826227ae5daaac465aa0969a74dc

commit f98caf44b80d826227ae5daaac465aa0969a74dc
Author: littledan <littledan@chromium.org>
Date: Tue May 10 06:54:17 2016

Various species micro-optimizations

- Inline reads to the species protector
- Put V8_LIKELY/V8_UNLIKELY to guide Array.prototype.{slice,splice,concat}
  to the fast paths
- Put the Array species good path checks directly in
  Array.prototype.concat to avoid a couple reads of the array constructor
  from the native context

These changes together bring a ~4-6% win on
kraken-orig/stanford-crypto-pbkdf2-orig which more than makes up from
the performance degradation from a recent other species-related change.

BUG= chromium:609739 
R=cbruni@chromium.org
LOG=Y

Review-Url: https://codereview.chromium.org/1958713003
Cr-Commit-Position: refs/heads/master@{#36121}

[modify] https://crrev.com/f98caf44b80d826227ae5daaac465aa0969a74dc/src/builtins.cc
[modify] https://crrev.com/f98caf44b80d826227ae5daaac465aa0969a74dc/src/isolate-inl.h
[modify] https://crrev.com/f98caf44b80d826227ae5daaac465aa0969a74dc/src/isolate.cc
[modify] https://crrev.com/f98caf44b80d826227ae5daaac465aa0969a74dc/src/isolate.h

I believe this was related to my CL, not Jyan's. Why was this marked M-50?

The patch didn't make it into today's Canary, but should be in tomorrow's Canary. That will give us insight as to its stability and whether it fixes that performance graph in automation. Once we have that information, I'd like to merge it to 51.

This is just a performance regression and does not need to be Restrict-View-Google.

Your change meets the bar and is auto-approved for M51 (branch: 2704)

The following revision refers to this bug:
  https://chromium.googlesource.com/v8/v8.git/+/fcb39c15853df5d23b7c91b12e88ecf1b0ae8d0f

commit fcb39c15853df5d23b7c91b12e88ecf1b0ae8d0f
Author: Dan Ehrenberg <littledan@chromium.org>
Date: Fri May 13 18:36:06 2016

Version 5.1.281.36 (cherry-pick)

Merged f98caf44b80d826227ae5daaac465aa0969a74dc

Various species micro-optimizations

BUG= chromium:609739 
LOG=N
R=adamk@chromium.org, adamk

Review URL: https://codereview.chromium.org/1977943002 .

Cr-Commit-Position: refs/branch-heads/5.1@{#44}
Cr-Branched-From: 167dc63b4c9a1d0f0fe1b19af93644ac9a561e83-refs/heads/5.1.281@{#1}
Cr-Branched-From: 03953f52bd4a184983a551927c406be6489ef89b-refs/heads/master@{#35282}

[modify] https://crrev.com/fcb39c15853df5d23b7c91b12e88ecf1b0ae8d0f/src/builtins.cc
[modify] https://crrev.com/fcb39c15853df5d23b7c91b12e88ecf1b0ae8d0f/src/isolate-inl.h
[modify] https://crrev.com/fcb39c15853df5d23b7c91b12e88ecf1b0ae8d0f/src/isolate.cc
[modify] https://crrev.com/fcb39c15853df5d23b7c91b12e88ecf1b0ae8d0f/src/isolate.h