- 28 Aug, 2017 1 commit
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Adam Klein authored
Per https://tc39.github.io/ecma262/#sec-array.prototype.concat, step 6. Bug: v8:6707, v8:6708 Change-Id: Iad3eb94a3b5fe35e5ecd1b8632612a7f2f169434 Reviewed-on: https://chromium-review.googlesource.com/636695 Commit-Queue: Adam Klein <adamk@chromium.org> Reviewed-by: Jakob Kummerow <jkummerow@chromium.org> Cr-Commit-Position: refs/heads/master@{#47654}
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- 24 Jun, 2016 1 commit
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adamk authored
Flags removed (all begin with "harmony-"): function-name instanceof iterator-close unicode-regexps regexp-exec regexp-subclass species BUG=v8:3566, v8:3648, v8:3699, v8:4093, v8:4447, v8:4602 Review-Url: https://codereview.chromium.org/2096933002 Cr-Commit-Position: refs/heads/master@{#37235}
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- 21 Mar, 2016 1 commit
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adamk authored
Both of them shipped in Chrome 49 without incident. Also move relevant tests from harmony/ to es6/. Review URL: https://codereview.chromium.org/1815773002 Cr-Commit-Position: refs/heads/master@{#34964}
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- 22 Feb, 2016 1 commit
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littledan authored
This patch makes ArraySpeciesCreate fast in V8 by avoiding two property reads when the following conditions are met: - No Array instance has had its __proto__ reset - No Array instance has had a constructor property defined - Array.prototype has not had its constructor changed - Array[Symbol.species] has not been reset For subclasses of Array, or for conditions where one of these assumptions is violated, the full lookup of species is done according to the ArraySpeciesCreate algorithm. Although this is a "performance cliff", it does not come up in the expected typical use case of @@species (Array subclassing), so it is hoped that this can form a good start. Array subclasses will incur the slowness of looking up @@species, but their use won't slow down invocations of, for example, Array.prototype.slice on Array base class instances. Possible future optimizations: - For the fallback case where the assumptions don't hold, optimize the two property lookups. - For Array.prototype.slice and Array.prototype.splice, even if the full lookup of @@species needs to take place, we still could take the rest of the C++ fastpath. However, to do this correctly requires changing the calling convention from C++ to JS to pass the @@species out, so it is not attempted in this patch. With this patch, microbenchmarks of Array.prototype.slice do not suffer a noticeable performance regression, unlike their previous 2.5x penalty. TBR=hpayer@chromium.org Review URL: https://codereview.chromium.org/1689733002 Cr-Commit-Position: refs/heads/master@{#34199}
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- 26 Jan, 2016 1 commit
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littledan authored
This patch makes Array.prototype.concat support subclassing Arrays and constructing instances properly with Symbol.species. It is guarded by the --harmony-species flag. R=cbruni LOG=Y BUG=v8:4093 Review URL: https://codereview.chromium.org/1577043002 Cr-Commit-Position: refs/heads/master@{#33503}
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- 07 Jan, 2016 1 commit
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littledan authored
This patch implements @@species, guarded behind the --harmony-species flag, on Arrays. Methods which return an Array will instead return the appropriate instance based on the ArraySpeciesCreate algorithm. The algorithm is implemented in C++ to get access to realm information and to implement some Array methods in C++, but it is also accessed from JavaScript through a new runtime function. A couple interactive Octane runs show no performance regression with the flag turned off, but turning --harmony-species on will surely have a significant regression, as Array methods now heavily use ObjectDefineProperty. BUG=v8:4093 LOG=Y R=adamk,cbruni Review URL: https://codereview.chromium.org/1560763002 Cr-Commit-Position: refs/heads/master@{#33144}
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