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  1. 16 Jul, 2015 1 commit
    • 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
  3. 17 Jun, 2015 1 commit
  5. 16 Jun, 2015 1 commit
    • littledan's avatar
      Add %TypedArray% to proto chain · a1059015
      littledan authored 
      According to the ES6 spec, the main methods and getters shouldn't
be properties of the individual TypedArray objects and prototypes
but instead on %TypedArray% and %TypedArray%.prototype. This
difference is observable through introspection. This patch moves
some methods and getters to the proper place, with the exception
of %TypedArray%.prototype.subarray and harmony methods. These will
be moved in follow-on patches.

BUG=v8:4085
LOG=Y
R=adamk

Review URL: https://codereview.chromium.org/1186733002

Cr-Commit-Position: refs/heads/master@{#29057}
      a1059015
  7. 15 Jun, 2015 1 commit
  9. 09 Jun, 2015 1 commit
    • dehrenberg's avatar
      Implement %TypedArray%.prototype.slice · 51df8df9
      dehrenberg authored 
      The initial implementation of this method takes a couple shortcuts:
- At some points in the spec, we should be making a reference to
  "Table 49" and instead do property lookup on the constructor.
  This is an issue with some other TypedArray methods too.
- The spec indicates that, if constructor and @@species haven't been
  messed with in particular ways, then there should be a memcpy
  from the old to the new. That fast path is not implemented here
  in this patch, but because V8 doesn't canonicalize NaN, the result
  isn't observably different.

BUG=v8:3578
LOG=Y
R=arv

Review URL: https://codereview.chromium.org/1170023002

Cr-Commit-Position: refs/heads/master@{#28882}
      51df8df9
  11. 04 Jun, 2015 1 commit
  13. 03 Jun, 2015 2 commits
  15. 02 Jun, 2015 1 commit
  17. 26 May, 2015 1 commit
  19. 22 May, 2015 4 commits
  21. 21 May, 2015 2 commits
  23. 20 May, 2015 5 commits
  25. 19 May, 2015 2 commits
  27. 18 May, 2015 1 commit
    • dehrenberg's avatar
      Add TypedArray.from method · cc3f59db
      dehrenberg authored 
      This function creates a new way to make TypedArrays based on existing
iterable or Array-like objects, analogous to Array.from. The patch
implements the function and adds tests.

R=arv@chromium.org
BUG=v8:3578
LOG=Y

Review URL: https://codereview.chromium.org/1132163011

Cr-Commit-Position: refs/heads/master@{#28456}
      cc3f59db
  29. 13 May, 2015 1 commit
  31. 12 May, 2015 5 commits
  33. 11 May, 2015 1 commit
  35. 09 May, 2015 1 commit
    • dehrenberg's avatar
      Make one copy for all TypedArray methods · ca9d499f
      dehrenberg authored 
      This is the first step of converting TypedArrays to the proper
proto chain. There is one copy for each of the Harmony TypedArray
methods, rather than a version for each TypedArray type. This
form prevents accidentally baking in knowledge about a particular
array type into the method definition.

R=adamk@chromium.org, arv@chromium.org, caitpotter88@gmail.com, dslomov@chromium.org, jochen@chromium.org
BUG=v8:4085
LOG=Y

Review URL: https://codereview.chromium.org/1126313003

Cr-Commit-Position: refs/heads/master@{#28325}
      ca9d499f
  37. 07 May, 2015 2 commits
  39. 06 May, 2015 3 commits
  41. 05 May, 2015 2 commits
  43. 04 May, 2015 1 commit