- 23 Apr, 2018 3 commits
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Sigurd Schneider authored
This is a reland of 5728b3fb Original change's description: > [builtins] Separate species protectors for Array, TypedArray, Promise > > Previously, there was one species protector for Array, TypedArray and > Promise. This CL splits the protector in three separate ones. This means > that invalidating one of them does not have negative performance > implications for the other ones. > > Bug: chromium:835347, v8:7340 > Change-Id: Id84aa0071f17096192965264eb60ddadd1e8e73f > Reviewed-on: https://chromium-review.googlesource.com/1023408 > Commit-Queue: Sigurd Schneider <sigurds@chromium.org> > Reviewed-by: Benedikt Meurer <bmeurer@chromium.org> > Cr-Commit-Position: refs/heads/master@{#52733} Bug: chromium:835347, v8:7340 Change-Id: I0c0188a0723e206ddb362834bcf872b23cd7666d Reviewed-on: https://chromium-review.googlesource.com/1023811 Commit-Queue: Benedikt Meurer <bmeurer@chromium.org> Reviewed-by: Benedikt Meurer <bmeurer@chromium.org> Cr-Commit-Position: refs/heads/master@{#52742}
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Sigurd Schneider authored
This reverts commit 5728b3fb. Reason for revert: Breaks noi18n build Original change's description: > [builtins] Separate species protectors for Array, TypedArray, Promise > > Previously, there was one species protector for Array, TypedArray and > Promise. This CL splits the protector in three separate ones. This means > that invalidating one of them does not have negative performance > implications for the other ones. > > Bug: chromium:835347, v8:7340 > Change-Id: Id84aa0071f17096192965264eb60ddadd1e8e73f > Reviewed-on: https://chromium-review.googlesource.com/1023408 > Commit-Queue: Sigurd Schneider <sigurds@chromium.org> > Reviewed-by: Benedikt Meurer <bmeurer@chromium.org> > Cr-Commit-Position: refs/heads/master@{#52733} TBR=sigurds@chromium.org,bmeurer@chromium.org Change-Id: Ied8b436e7991c759eb3b98702c142aa127a7e63c No-Presubmit: true No-Tree-Checks: true No-Try: true Bug: chromium:835347, v8:7340 Reviewed-on: https://chromium-review.googlesource.com/1024151Reviewed-by: Sigurd Schneider <sigurds@chromium.org> Commit-Queue: Sigurd Schneider <sigurds@chromium.org> Cr-Commit-Position: refs/heads/master@{#52736}
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Sigurd Schneider authored
Previously, there was one species protector for Array, TypedArray and Promise. This CL splits the protector in three separate ones. This means that invalidating one of them does not have negative performance implications for the other ones. Bug: chromium:835347, v8:7340 Change-Id: Id84aa0071f17096192965264eb60ddadd1e8e73f Reviewed-on: https://chromium-review.googlesource.com/1023408 Commit-Queue: Sigurd Schneider <sigurds@chromium.org> Reviewed-by: Benedikt Meurer <bmeurer@chromium.org> Cr-Commit-Position: refs/heads/master@{#52733}
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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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- 04 May, 2016 1 commit
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littledan authored
Previously, the species protector was invalidated whenever the __proto__ of an Array instance was manipulated. Then, if the map's new_target_is_base field remained set, it was correct to conclude that GetPrototypeOf(array) was %ArrayPrototype%. However, this choice caused the popular D3 framework to invalidate the species protector, causing many functions to become slower. This patch eliminates that aspect of the species protector. Instead, the check is to look at the instance->map()->prototype(). It is valid to look directly at the map's prototype slot, ignoring hidden prototypes and proxies, because - This is only called on Array instances, so the receiver cannot be a Proxy. - For hidden prototypes, any inaccuracy would only result in conservatively taking the slow path. Theoretically, this patch could make methods applied to arrays from other contexts slower. However, the slowdown would only affect a particular array instance and not have a global spill-over effect. Further, the slowdown could be addressed by tracking, either in the instance's map or in the actual prototype object, whether it is a %ArrayPrototype% from any context, in a way which is cheap to query, and use that rather than comparing to the currently executing native context. In interactive testing, this patch led the OnShape CAD system to experience faster load times (110+s -> 40s). BUG=chromium:606207 LOG=Y Review-Url: https://codereview.chromium.org/1936393002 Cr-Commit-Position: refs/heads/master@{#36033}
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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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