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  1. 20 Jul, 2015 13 commits
  3. 19 Jul, 2015 1 commit
  5. 18 Jul, 2015 1 commit
  7. 17 Jul, 2015 21 commits
  9. 16 Jul, 2015 4 commits
    • littledan's avatar
      Array.prototype.reverse should call [[HasProperty]] on elements before [[Get]] · f76dfee9
      littledan authored 
      This is a change from ES5 to ES6: When reversing an array, first it is checked
whether the element exists, before the element is looked up. The order in ES6
is

[[HasElement]] lower
[[Get]] lower (if present)
[[HasElement]] upper
[[Get]] upper (if present)

In ES5, on the other hand, the order was

[[Get]] lower
[[Get]] upper
[[HasElement]] lower
[[HasElement]] upper

To mitigate the performance impact, this patch implements a new, third copy
of reversing arrays if %_HasPackedElements. This allows us to skip all
membership tests, and a quick and dirty benchmark shows that the new version
is faster:

Over 4 runs, the slowest for the new version:
d8> var start = Date.now(); for (var i = 0; i < 100000000; i++) [1, 2, 3, 4, 5].reverse(); Date.now() - start
4658

Over 3 runs, the fastest for the old version:
d8> var start = Date.now(); for (var i = 0; i < 100000000; i++) [1, 2, 3, 4, 5].reverse(); Date.now() - start
5176

BUG=v8:4223
R=adamk
LOG=Y

Review URL: https://codereview.chromium.org/1238593003

Cr-Commit-Position: refs/heads/master@{#29716}
      f76dfee9
    • littledan's avatar
      In RegExp, lastIndex is read with ToLength, not ToInteger · 1f61ac50
      littledan authored 
      ES2015 made a change vs ES5, where the "lastIndex" property of a
RegExp (which can be modified by a user to start the next search at
a different location) is cast to an integer with ToLength rather
than ToInteger. The main difference is on negative numbers, and
this is tested by test262. This patch implements that change on
RegExps and enables the test262 test now that it passes.

R=adamk
LOG=Y
BUG=v8:4244

Review URL: https://codereview.chromium.org/1241713004

Cr-Commit-Position: refs/heads/master@{#29715}
      1f61ac50
    • adamk's avatar
      Stage --harmony-new-target · 5906ce33
      adamk authored 
      BUG=v8:3887
LOG=y

Review URL: https://codereview.chromium.org/1238693004

Cr-Commit-Position: refs/heads/master@{#29714}
      5906ce33
    • adamk's avatar
      Re-ship harmony spread calls and spread arrays · bd389ec0
      adamk authored 
      The issue with spread arrays which caused us to turn it off was fixed in
https://chromium.googlesource.com/v8/v8/+/24e98281

BUG=v8:3018
LOG=y

Review URL: https://codereview.chromium.org/1239873002

Cr-Commit-Position: refs/heads/master@{#29713}
      bd389ec0