* 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 fixes a corner-case where deoptimization while evaluating the
value to a __proto__ property after computed property names appeared
in an object literal, lead to environments not being in sync with
unoptimized code.
R=arv@chromium.org
TEST=mjsunit/harmony/computed-property-names-deopt
Review URL: https://codereview.chromium.org/1158443004
Cr-Commit-Position: refs/heads/master@{#28613}
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}
First steps only, the TurboFan compilation is still triggered from C++ land.
Includes some simplifications/cleanups, too.
Review URL: https://codereview.chromium.org/1150263002
Cr-Commit-Position: refs/heads/master@{#28581}
Also support patterns in ``for (var p in/of ...)``
This CL extends the rewriting we used to do for ``for (let p in/of...)`` to
``for (var p in/of ...)``. For all for..in/of loop declaring variable,
we rewrite
for (var/let/const pattern in/of e) b
into
for (x' in/of e) { var/let/const pattern = e; b }
This adds a small complication for debugger: for a statement
for (var v in/of e) ...
we used to have
var v;
for (v in/of e) ...
and there was a separate breakpoint on ``var v`` line.
This breakpoint is actually useless since it is immediately followed by
a breakpoint on evaluation of ``e``, so this CL removes that breakpoint
location.
Similiraly, for let, it used to be that
for (let v in/of e) ...
became
for (x' in/of e) { let v; v = x'; ... }
``let v``generetaed a useless breakpoint (with the location at the
loop's head. This CL removes that breakpoint as well.
R=arv@chromium.org,rossberg@chromium.org
BUG=v8:811
LOG=N
Review URL: https://codereview.chromium.org/1149043005
Cr-Commit-Position: refs/heads/master@{#28565}
This allows you to put iterables into your array literals
and the will get spread into the array.
let x = [0, ...range(1, 3)]; // [0, 1, 2]
This is done by treating the array literal up to the first
spread element as usual, including using a boiler plate
array, and then appending the remaining expressions and rest
expressions.
BUG=v8:3018
LOG=N
Review URL: https://codereview.chromium.org/1125183008
Cr-Commit-Position: refs/heads/master@{#28534}
Previously this patch was attempted with reduce and reduceRight included;
however, some of those tests crashed in the trybots. This version has
just map, fiter and some, together with their tests.
R=arv@chromium.org
BUG=v8:3578
LOG=Y
Review URL: https://codereview.chromium.org/1145013002
Cr-Commit-Position: refs/heads/master@{#28529}
This patch adds the two TypedArray methods indexOf and lastIndexOf,
which are similar to the methods on Arrays. Tests are ported from
arrays as well.
BUG=v8:3578
LOG=Y
R=arv@chromium.org
Review URL: https://codereview.chromium.org/1141763004
Patch from Daniel Ehrenberg <dehrenberg@chromium.org>.
Cr-Commit-Position: refs/heads/master@{#28495}
The sort method of TypedArrays sorts in numerical order by default.
This patch implements sorting based on Arrays and adds a test.
The length of %TypedArray%.prototype.sort, like Array.prototype.sort,
seems to be unspecified in ES6, so this patch lets it have the value
1, to match our interpretation for Array.prototype.sort (though 0
would also be a sensible length).
R=arv@chromium.org
BUG=v8:3578
LOG=Y
Review URL: https://codereview.chromium.org/1148513002
Patch from Daniel Ehrenberg <dehrenberg@chromium.org>.
Cr-Commit-Position: refs/heads/master@{#28494}
This patch adds the reverse method to TypedArrays, together with a
test. The test also runs for normal Arrays, since I didn't see a
test for reversing dense arrays.
BUG=v8:3578
LOG=Y
R=arv@chromium.org
Review URL: https://codereview.chromium.org/1132723008
Patch from Daniel Ehrenberg <dehrenberg@chromium.org>.
Cr-Commit-Position: refs/heads/master@{#28493}
Also check whether the arguments count is smaller than the number of
required parameters which is the same as the SharedFunctionInfo length.
BUG=v8:4102
LOG=N
R=rossberg@chromium.org
Review URL: https://codereview.chromium.org/1133933003
Cr-Commit-Position: refs/heads/master@{#28491}
This patch adds implementations for additional TypedArray methods
from the ES6 spec, together with tests adapted from array code.
R=arv@chromium.org
BUG=v8:3578
LOG=Y
Review URL: https://codereview.chromium.org/1139663005
Cr-Commit-Position: refs/heads/master@{#28488}
