We currently grow the backing store to (old_capacity*1.5)+16 if we exceed capacity,
but shrink the capacity to the current length when 2*length <= capacity.
For short arrays (up to length 32), this can lead to a copy on every operation when using push/pop or push/shift.
Example:
Array of length 32, capacity 32
push
Array grown to length 33, capacity 32*1.5+16 = 64
pop
Array trimmed to length 32, capacity 32 because 2*32 <= 64
...
This CL leaves additional slag space when calling pop and restricts the trimming to backing stores with at least 16 elements to prevent excessive re-trimming on short arrays.
Bug:
Change-Id: I9dd13e5e2550c7ac819294c8e29f04c8855e02a4
Reviewed-on: https://chromium-review.googlesource.com/502911
Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45324}
No semantic changes, just a readability refactoring that removes
a couple of unnecessary variables and labels.
BUG=v8:6371
Review-Url: https://codereview.chromium.org/2881763003
Cr-Commit-Position: refs/heads/master@{#45290}
Smis can easily be handled outside the stub call without adding much to code
size.
The ToString inlining adds overhead of repeated instance type loads and checks,
but under the assumption that it is called with mostly string values it should
speed things up (a local RegExp.p[@@replace] microbenchmark shows consistent
1.6% improvements).
Drive-by-fix: Remove duplication in ToString implementations.
BUG=
Review-Url: https://codereview.chromium.org/2874423003
Cr-Commit-Position: refs/heads/master@{#45287}
No need to call through ConstructJS -> ArrayCode -> ArrayConstructorStub
-> AllocateJSArray if we can call AllocateJSArray directly.
This also moves ArraySpeciesCreate to builtins-array-gen to free
up space in the binary.
BUG=v8:6354
Review-Url: https://codereview.chromium.org/2874833004
Cr-Commit-Position: refs/heads/master@{#45276}
Mechanical change to remove argument adaption from Array.p.indexOf and
Array.p.includes when the actual arguments counts does not match the formal
parameter count.
BUG=v8:6369
Review-Url: https://codereview.chromium.org/2873653002
Cr-Commit-Position: refs/heads/master@{#45218}
More care must be taken to remain on the fast path in the face of
@@species constructors.
BUG=chromium:716044
Review-Url: https://codereview.chromium.org/2846963003
Cr-Commit-Position: refs/heads/master@{#45065}
This CL changes certain frequently-called Array builtins to use CodeStubArguments
rather than peek at the stack frames above array builtins to determine if options
arguments have been passed into them.
Previous failure likely due to unfortunate/unluckily timed GC that moved due to
changed timing/allocation from this CL. Test mitigation for allocation-site-info.js
included.
BUG=v8:1956
LOG=N
Review-Url: https://codereview.chromium.org/2829093004
Cr-Commit-Position: refs/heads/master@{#44998}
Reason for revert:
Still fails. Likely has to do with gc heap size for allocation site tests, mitigation pending...
Original issue's description:
> [turbofan] Reland: Avoid going through ArgumentsAdaptorTrampoline for select CSA array builtins
>
> This CL changes certain frequently-called Array builtins to use CodeStubArguments
> rather than peek at the stack frames above array builtins to determine if options
> arguments have been passed into them.
>
> Previous failure cannot be reproed with failing config. Flake?
>
> BUG=v8:1956
> LOG=N
>
> Review-Url: https://codereview.chromium.org/2829093004
> Cr-Commit-Position: refs/heads/master@{#44996}
> Committed: 7ca381e847TBR=mvstanton@chromium.org,ishell@chromium.org,bmeurer@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:1956
Review-Url: https://codereview.chromium.org/2851063002
Cr-Commit-Position: refs/heads/master@{#44997}
This CL changes certain frequently-called Array builtins to use CodeStubArguments
rather than peek at the stack frames above array builtins to determine if options
arguments have been passed into them.
Previous failure cannot be reproed with failing config. Flake?
BUG=v8:1956
LOG=N
Review-Url: https://codereview.chromium.org/2829093004
Cr-Commit-Position: refs/heads/master@{#44996}
Reason for revert:
Nosnap failure
Original issue's description:
> [turbofan] Avoid going through ArgumentsAdaptorTrampoline for select CSA/C++ builtins
>
> This CL changes certain frequently-called Array builtins to use CodeStubArguments
> rather than peek at the stack frames above array builtins to determine if options
> arguments have been passed into them.
>
> BUG=v8:1956
> LOG=N
>
> Review-Url: https://codereview.chromium.org/2829093004
> Cr-Commit-Position: refs/heads/master@{#44994}
> Committed: 680356278dTBR=mvstanton@chromium.org,ishell@chromium.org,bmeurer@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:1956
Review-Url: https://codereview.chromium.org/2851703005
Cr-Commit-Position: refs/heads/master@{#44995}
This CL changes certain frequently-called Array builtins to use CodeStubArguments
rather than peek at the stack frames above array builtins to determine if options
arguments have been passed into them.
BUG=v8:1956
LOG=N
Review-Url: https://codereview.chromium.org/2829093004
Cr-Commit-Position: refs/heads/master@{#44994}
filter creates an output array with the Array species constructor for
storing values from the input array that pass the user-supplied
predicate function. Our new array builtins are implemented such that
if we fall out of the fast path, we'll pick up where we left off
in a continuation function. It's important to pass the index of
where we left off appending to the output array, because otherwise
we will read it at the start of the continuation function.
That would be observable, and a spec violation.
BUG=
Review-Url: https://codereview.chromium.org/2771483002
Cr-Commit-Position: refs/heads/master@{#44023}
Second bulk of changes.
BUG=v8:6116
Change-Id: I6297c4e3e1c0230a96dc6197691a54c07cc61c88
Reviewed-on: https://chromium-review.googlesource.com/457320
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#43995}
This is a first bulk of changes.
BUG=v8:6116
Change-Id: I9308129bd032c0bf5b60c8e0413ee2cb710891ea
Reviewed-on: https://chromium-review.googlesource.com/456556
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#43930}
Previous to this CL, CSA-optimized Array builtins--like forEach, some, and
every--were written in a single, monolithic block of CSA code.
This CL teases the code for each of these builtins apart into two chunks, a main
body with optimizations for fast cases, and a "continuation" builtin that
performs a spec-compliant, but slower version of the main loop of the
builtin. The general idea is that when the "fast" main body builtin encounters
an unexpected condition that invalidates assumptions allowing fast-case code, it
tail calls to the slow, correct version of the loop that finishes the builtin
execution.
This separation currently doens't really provide any specific advantage over the
combined version. However, it paves the way to TF-optimized inlined Array
builtins. Inlined Array builtins may trigger deopts during the execution of the
builtin's loop, and those deopt must continue execution from the point at which
they failed. With some massaging of the deoptimizer, it will be possible to make
those deopt points create an extra frame on the top of the stack which resumes
execution in the slow-loop builtin created in this CL.
BUG=v8:1956
LOG=N
Review-Url: https://codereview.chromium.org/2753793002
Cr-Commit-Position: refs/heads/master@{#43867}
This is in preparation for linking the former only into mksnapshot.
Just shuffling code around, no changes in functionality.
BUG=v8:6055
Review-Url: https://codereview.chromium.org/2752143004
Cr-Commit-Position: refs/heads/master@{#43858}
