Only supports constructing new objects and returning size.
Followup patch will need to add ability to retrieve and
set contents in order to support structured clone.
Also removes a bunch of outdated "experimental" markers from v8.h.
BUG=v8:3340
LOG=y
Review URL: https://codereview.chromium.org/1157453002
Cr-Commit-Position: refs/heads/master@{#28637}
* Hash code is now just done with a private own symbol instead of the hidden string, which predates symbols.
* In the long run we should do all hidden properties this way and get rid of the
hidden magic 0-length string with the zero hash code. The advantages include
less complexity and being able to do things from JS in a natural way.
* Initially, the performance of weak set regressed, because it's a little harder
to do the lookup in C++. Instead of heroics in C++ to make things faster I
moved some functionality into JS and got the performance back. JS is supposed to be good at looking up named properties on objects.
* This also changes hash codes of Smis so that they are always Smis.
Performance figures are in the comments to the code review. Summary: Most of js-perf-test/Collections is neutral. Set and Map with object keys are 40-50% better. WeakMap is -5% and WeakSet is +9%. After the measurements, I fixed global proxies, which cost 1% on most tests and 5% on the weak ones :-(.
In the code review comments is a patch with an example of the heroics we could do in C++ to make lookup faster (I hope we don't have to do this. Instead of checking for the property, then doing a new lookup to insert it, we could do one lookup and handle the addition immediately). With the current benchmarks above this buys us nothing, but if we go back to doing more lookups in C++ instead of in stubs and JS then it's a win.
In a similar vein we could give the magic zero hash code to the hash code
symbol. Then when we look up the hash code we would sometimes see the table
with all the hidden properties. This dual use of the field for either the hash
code or the table with all hidden properties and the hash code is rather ugly,
and this CL gets rid of it. I'd be loath to bring it back. On the benchmarks quoted above it's slightly slower than moving the hash code lookup to JS like in this CL.
One worry is that the benchmark results above are more monomorphic than real
world code, so may be overstating the performance benefits of moving to JS. I
think this is part of a general issue we have with handling polymorphic code in
JS and any solutions there will benefit this solution, which boils down to
regular property access. Any improvement there will lift all boats.
R=adamk@chromium.org, verwaest@chromium.org
BUG=
Review URL: https://codereview.chromium.org/1149863005
Cr-Commit-Position: refs/heads/master@{#28622}
This adds a new external type (v8::SharedArrayBuffer) that uses a JSArrayBuffer
under the hood. It can be distinguished from an ArrayBuffer by the newly-added
is_shared() bit.
Currently there is no difference in functionality between a SharedArrayBuffer
and an ArrayBuffer. However, a future CL will add the Atomics API, which is
only available on an SharedArrayBuffer. All non-atomic accesses are identical
to ArrayBuffer accesses.
LOG=N
BUG=
Review URL: https://codereview.chromium.org/1136553006
Cr-Commit-Position: refs/heads/master@{#28594}
Reason for revert:
breaks build
Original issue's description:
> Implement SharedArrayBuffer.
>
> This adds a new external type (v8::SharedArrayBuffer) that uses a JSArrayBuffer under the hood. It can be distinguished from an ArrayBuffer by the newly-added is_shared() bit.
>
> Currently there is no difference in functionality between a SharedArrayBuffer and an ArrayBuffer. However, a future CL will add the Atomics API, which is only available on an SharedArrayBuffer. All non-atomic accesses are identical to ArrayBuffer accesses.
>
> BUG=
>
> Committed: https://crrev.com/57170bff7baf341c666252a7f6a49e9c08d51263
> Cr-Commit-Position: refs/heads/master@{#28588}
TBR=jarin@chromium.org,jochen@chromium.org,binji@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=
Review URL: https://codereview.chromium.org/1149203003
Cr-Commit-Position: refs/heads/master@{#28589}
This adds a new external type (v8::SharedArrayBuffer) that uses a JSArrayBuffer under the hood. It can be distinguished from an ArrayBuffer by the newly-added is_shared() bit.
Currently there is no difference in functionality between a SharedArrayBuffer and an ArrayBuffer. However, a future CL will add the Atomics API, which is only available on an SharedArrayBuffer. All non-atomic accesses are identical to ArrayBuffer accesses.
BUG=
Review URL: https://codereview.chromium.org/1136553006
Cr-Commit-Position: refs/heads/master@{#28588}
Reason for revert:
I'm reverting this while working on the regression fix
Original issue's description:
> Remove the weak list of views from array buffers
>
> Instead, views have to check their array buffer for whether
> it's neutered or not.
>
> BUG=v8:3996
> R=hpayer@chromium.org,dslomov@chromium.org,verwaest@chromium.org
> LOG=n
>
> Committed: https://crrev.com/5ae083a05a6743d6cb91585f449539f7846a5d8c
> Cr-Commit-Position: refs/heads/master@{#27995}
TBR=dslomov@chromium.org,hpayer@chromium.org,verwaest@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:3996
Review URL: https://codereview.chromium.org/1061753008
Cr-Commit-Position: refs/heads/master@{#28014}
Instead, views have to check their array buffer for whether
it's neutered or not.
BUG=v8:3996
R=hpayer@chromium.org,dslomov@chromium.org,verwaest@chromium.org
LOG=n
Review URL: https://codereview.chromium.org/1094863002
Cr-Commit-Position: refs/heads/master@{#27995}
Reason for revert:
Breaks gbemu
Original issue's description:
> Reland "LayoutDescriptor should inherit from JSTypedArray"
>
> Original issue's description:
> > LayoutDescriptor should inherit from JSTypedArray
> >
> > It can't just inherit from a FixedTypedArray-like type, as we soon
> > assume that a FixedTypedArray-like type is always held by an
> > ArrayBufferView-like type
> >
> > BUG=v8:3996
> > R=ishell@chromium.org,verwaest@chromium.org
> > LOG=n
>
> BUG=v8:3996
> R=ishell@chromium.org,verwaest@chromium.org
> LOG=n
TBR=ishell@chromium.org,verwaest@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:3996
Review URL: https://codereview.chromium.org/1080403004
Cr-Commit-Position: refs/heads/master@{#27975}
Original issue's description:
> LayoutDescriptor should inherit from JSTypedArray
>
> It can't just inherit from a FixedTypedArray-like type, as we soon
> assume that a FixedTypedArray-like type is always held by an
> ArrayBufferView-like type
>
> BUG=v8:3996
> R=ishell@chromium.org,verwaest@chromium.org
> LOG=n
BUG=v8:3996
R=ishell@chromium.org,verwaest@chromium.org
LOG=n
Review URL: https://codereview.chromium.org/1094333002
Cr-Commit-Position: refs/heads/master@{#27973}
Reason for revert:
breaks mjsunit on debug bots
Original issue's description:
> LayoutDescriptor should inherit from JSTypedArray
>
> It can't just inherit from a FixedTypedArray-like type, as we soon
> assume that a FixedTypedArray-like type is always held by an
> ArrayBufferView-like type
>
> BUG=v8:3996
> R=ishell@chromium.org,verwaest@chromium.org
> LOG=n
TBR=ishell@chromium.org,verwaest@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:3996
Review URL: https://codereview.chromium.org/1073053006
Cr-Commit-Position: refs/heads/master@{#27968}
It can't just inherit from a FixedTypedArray-like type, as we soon
assume that a FixedTypedArray-like type is always held by an
ArrayBufferView-like type
BUG=v8:3996
R=ishell@chromium.org,verwaest@chromium.org
LOG=n
Review URL: https://codereview.chromium.org/1084793004
Cr-Commit-Position: refs/heads/master@{#27964}
The motivation is that we prefer to avoid creating internal properties, and we have a usable field on maps ("transitions", which is not used for prototype maps).
This CL also ensures the invariant that prototype maps are never shared, even if they are in dictionary mode.
Review URL: https://codereview.chromium.org/1033653002
Cr-Commit-Position: refs/heads/master@{#27617}
No compiler support for now (BTW: %_NewString, doesn't have that,
either), inline allocation will come later. Hopefully the last
intrisic to add for a StringAddStub POC...
Review URL: https://codereview.chromium.org/1041723002
Cr-Commit-Position: refs/heads/master@{#27508}
The cause was dynamic allocation of an accounting structure used to
create/initialize the type feedback vector, done at the end of the
numbering pass. The solution is to Zone-allocate the structure to
bring it's lifetime in line with the compilation unit.
BUG=
Review URL: https://codereview.chromium.org/1014793003
Cr-Commit-Position: refs/heads/master@{#27241}
We no longer expect NewError to return an empty handle to signal termination
exception, since TryCall simply requests a new terminate exception interrupt.
BUG=chromium:403509
LOG=N
Review URL: https://codereview.chromium.org/952483002
Cr-Commit-Position: refs/heads/master@{#26811}
A new map wich references its keys weakly is added to v8.h. Internally it uses the same storage as JSWeakMap but doesn't depend on the JavaScript part of WeakMap implementation in weak-collection.js, hence it can be instantiated without entering any context.
BUG=chromium:437416
LOG=Y
Review URL: https://codereview.chromium.org/900123003
Cr-Commit-Position: refs/heads/master@{#26451}
A new map wich references its keys weakly is added to v8.h. Internally it uses the same storage as JSWeakMap but doesn't depend on the JavaScript part of WeakMap implementation in weak-collection.js, hence it can be instantiated without entering any context.
BUG=chromium:437416
LOG=Y
Review URL: https://codereview.chromium.org/891473005
Cr-Commit-Position: refs/heads/master@{#26425}
A new map wich references its keys weakly is added to v8.h. Internally it uses the same storage as JSWeakMap but doesn't depend on the JavaScript part of WeakMap implementation in weak-collection.js, hence it can be instantiated without entering any context.
BUG=chromium:437416
LOG=Y
Review URL: https://codereview.chromium.org/886473005
Cr-Commit-Position: refs/heads/master@{#26401}
