Add VirtualBoundFunction to the serializer which takes care of
processing the result of Function.prototype.bind.
Add cctest and an mjsunit test.
Bug: v8:7790
Change-Id: Ic2b48d356cbe3b576eb22f58215cc886a8994e31
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1859625
Commit-Queue: Michael Stanton <mvstanton@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#64548}
The serializer doesn't correctly propagate environment information
from try blocks into their catch handlers, and this impedes
optimizations that fire when we compile concurrently.
function bar(x) {
try {
boom(); // throws
} catch(_) {
return x.a;
}
}
function foo() { return bar({a: 42}); }
When foo is optimized, we can normally return the constant 42
directly. This CL makes that work for concurrent inlining.
Bug: v8:7790
Change-Id: Id1c5fd06d51ec6fe69ab10fbd65afd6fa7e76820
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1863193
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Commit-Queue: Michael Stanton <mvstanton@chromium.org>
Cr-Commit-Position: refs/heads/master@{#64352}
We used to have two special cases for named accesses on the global
proxy, one based on seeing the global proxy constant in the graph and
on based on seeing the global proxy map either in the feedback or in
the graph. A change I made a while ago accidentally disabled the second
one. This CL restores that.
Moreover, given how things are set up now (this might have been
different before), the first optimization is subsumed by the second
one, so this CL also removes the first one.
Finally, this CL records an accumulator hint in the case of a load,
which improves precision of the serializer for concurrent inlining.
Tbr: tebbi@chromium.org
Bug: v8:7790
Change-Id: I255afc6c79e5c5c900b3ccfcd8459d836d21e42b
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1801954
Commit-Queue: Georg Neis <neis@chromium.org>
Reviewed-by: Michael Stanton <mvstanton@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63806}
This reimplements the "--time" option of run-tests.py to print the
20 slowest tests, on top of json_test_results infrastructure just
like the bots do it.
Additionally this CL speeds up a bunch of slow tests.
Bug: v8:9396
Change-Id: I40797d2c8c3bfdd310b72f15cd1a035844b7c6f3
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1803635
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63786}
This reverts commit 9ce6792630.
Reason for revert: This was never intended to stay.
Original change's description:
> [turbofan] temporarily disable const-based load elimination
>
> This is a safe to merge hot-fix to tackle https://crbug.com/983764.
> To be reverted after merging to M77.
>
> Bug: chromium:983764
> Change-Id: I3cd27481f224b352ef6bcf9dde21a8f77616acff
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1786285
> Reviewed-by: Maya Lekova <mslekova@chromium.org>
> Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#63570}
TBR=tebbi@chromium.org,mslekova@chromium.org
# Not skipping CQ checks because original CL landed > 1 day ago.
Bug: chromium:983764
Change-Id: I9c07eab384818aaeecab0224cec0f6b5310e9e09
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1801839
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63743}
Change-Id: Ie0bd818c629bed3011212fb7c8ab81202a462501
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1798424
Reviewed-by: Peter Marshall <petermarshall@chromium.org>
Commit-Queue: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63678}
This is a safe to merge hot-fix to tackle https://crbug.com/983764.
To be reverted after merging to M77.
Bug: chromium:983764
Change-Id: I3cd27481f224b352ef6bcf9dde21a8f77616acff
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1786285
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63570}
This is a reland of ab089c7864, after
making a flaky test more robust.
Original change's description:
> [turbofan] Prepare for moving part of CreateGraph into the background
>
> - Pass Refs, not Handles, to graph builder, and drop bytecode array argument
> (get it from SFI instead).
> - Add some fields to FeedbackVectorRef that are needed to avoid heap access
> in BytecodeGraphBuilderPhase.
> - Rename FeedbackVectorRef's SerializeSlots to Serialize, since it's more
> than just the feedback slots.
> - Rearrange the last steps in PipelineCompilationJob::PrepareJobImpl such
> that CreateGraph is last.
>
> Bug: v8:7790
> Change-Id: I4b17790d1d74da41ba63ee68e3a33968662fc398
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1781682
> Reviewed-by: Maya Lekova <mslekova@chromium.org>
> Commit-Queue: Georg Neis <neis@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#63515}
Bug: v8:7790
Change-Id: Ia6f4c1ebd82dea93c14437514d0e25b730523f75
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1781694
Reviewed-by: Georg Neis <neis@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Commit-Queue: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63545}
This CL try to use a phi as a branch condition if the control flow from the
branch is known from previous conditions. This change will open up more branch
folding opportunities for later pass.
Change-Id: I26316ab3a68c2d58d0df53691981288a996d4ba1
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1674484
Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63434}
Currently the backing store and elements kind might not aligned aka
backing store can be dictionary where elements kind is frozen/sealed
element kinds or the other way around. The reason is that
Object.preventExtensions change elements kind to DICTIONARY while
Object.seal/freeze change elements kind to SEALED/FROZEN element kind.
Apply both these operations can lead to that problem as in
chromium:992914
To solve this issue, we avoid Object.preventExtensions to change backing
store to dictionary by introducing new nonextensible elements kind.
These new nonextensible elements kind are handled similar to frozen,
sealed element kinds. This change not only fixes the problem but also
optimize the performance of nonextensible objects.
Change-Id: Iffc7f14eb48223c11abf3c577f305d2d072eb65b
Bug: chromium:992914, v8:6831
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1760976
Commit-Queue: Z Nguyen-Huu <duongn@microsoft.com>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63432}
While we only need to check stability of the receiver map if its
inference was "unreliable", we must check stability of each prototype's
map unconditionally.
Bug: chromium:997100
Change-Id: I20071ac9eb74c810ad2ab1d78abfb54a1a006c29
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1768576
Commit-Queue: Maya Lekova <mslekova@chromium.org>
Auto-Submit: Georg Neis <neis@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63364}
This brings the graph builder in sync with the serializer (and
exponentiation in sync with the other binary operators).
Bug: chromium:995430, v8:7790
Change-Id: I809b6f3756f75392cdc6747f8bcee8cdf0ee0f74
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1762013
Commit-Queue: Georg Neis <neis@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63269}
... by making the operator have a control output, since we could deopt
after my last change.
Bug: chromium:995562, v8:7790
Change-Id: Ibc8c44708b4d43c4b2c3dfab2fd8fdf79c7ea671
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1762010
Commit-Queue: Georg Neis <neis@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63268}
Ongoing cleanup to use the same term everywhere.
Bug: chromium:913887
Change-Id: Ifc4d4de0c2dfd9f1150e61d64cf7f91cf923aa24
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1738865
Reviewed-by: Simon Zünd <szuend@chromium.org>
Commit-Queue: Peter Marshall <petermarshall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63101}
Serialize for all cases of JSNativeContextSpecialization::ReduceJSInstanceOf.
Bug: v8:7790
Change-Id: I147991353b86619808257a92961b7051105511f1
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1722558
Commit-Queue: Georg Neis <neis@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62965}
- Move SerializePrototype out of DependOnStablePrototypes into
ComputePropertyAccessInfo.
- Brokerize JSNativeContextSpecialization::InferHasInPrototypeChain.
- Brokerize JSNativeContextSpecialization::ReduceJSOrdinaryHasInstance
(modulo the call to ReduceJSInstanceOf).
- Brokerize JSNativeContextSpecialization::ReduceJSHasInPrototypeChain.
- Serialize for JSCallReducer::ReduceObjectPrototypeIsPrototypeOf.
- Serialize for JSNativeContextSpecialization::ReduceJSInstanceOf. This
is still incomplete.
Bug: v8:7790
Change-Id: Ic56eab5ddd8d725a13d2980e5b55db53ae82e822
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1709408
Commit-Queue: Georg Neis <neis@chromium.org>
Reviewed-by: Michael Stanton <mvstanton@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62920}
RepresentationChanger::GetTaggedPointerRepresentation did not handle
kCompressed cases correctly for BigInts. This led to a crash of BigInt
benchmarks in js-perf-test.
Bug: v8:9407
Change-Id: Id1d60a81afc528c8d4180bd5de9d237f2f0abd0a
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1701848
Reviewed-by: Georg Neis <neis@chromium.org>
Reviewed-by: Sigurd Schneider <sigurds@chromium.org>
Commit-Queue: Sigurd Schneider <sigurds@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62718}
The bytecode graph builder may insert additional jumps for the
SwitchOnGeneratorState bytecode and for loop headers. This plays into
what the graph builder considers dead/alive. We want the serializer to
process all the bytecodes that the graph builder will process, so the
serializer needs to do something similar.
Bug: v8:7790
Change-Id: I1f1d51f4a8951149e365b3c998cef7f613bb4953
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1647694
Commit-Queue: Georg Neis <neis@chromium.org>
Reviewed-by: Michael Stanton <mvstanton@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62712}
This change implements lowering of speculative BigInt addition as well as
BigInt heap constants to corresponding int64 versions, if they are used in
a context where the result is truncated to the least significant 64 bits
(e.g. using asUintN). The JSHeapBroker is extended to provide access to the
BigInt's least significant digit during concurrent compilation. The BigInt
context (required to introduce correct conversions) is recognized in the
RepresentationChanger by either the output type propagated downward or the
TypeCheckKind propagated upward. This is necessary, because the TypeCheckKind
may only be set by nodes that may potentially deopt (and sit in the effect
chain). This is the case for SpeculativeBigIntAdd, but not for BigIntAsUintN.
This CL contains a simple fix to prevent int64-lowered BigInts to flow into
state values as the deoptimizer cannot handle them yet. A more sophisticated
solution to allow the deoptimizer to materialize truncated BigInts will be
added in a following CL.
Bug: v8:9407
Change-Id: I96a293e9077962f53e5f199857644f004e3ae56e
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1684183
Commit-Queue: Nico Hartmann <nicohartmann@google.com>
Reviewed-by: Georg Neis <neis@chromium.org>
Reviewed-by: Sigurd Schneider <sigurds@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62665}
This CL adds the --assert-types flag to d8, which is intended to
insert additional runtime checks after typed nodes, verifying the
validity of our typing rules. So far, only range types are checked.
Thanks to Neil Patil for suggesting something similar.
R=neis@chromium.org, tebbi@chromium.org
Change-Id: I5eb2c482235ec8cd07ee802ca7c12c86c2d3dc40
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1678372
Commit-Queue: Georg Schmid <gsps@google.com>
Reviewed-by: Georg Neis <neis@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62664}
With lazy feedback allocation and bytecode flushing we need to call
%PrepareFunctionForOptimize before we call %OptimizeFunctionOnNextCall/
%OptimizeOsr. This cl:
1. Adds an additional state in pending optimized table to check if the
optimization was triggered manually.
2. Changes the compilation pipeline to delete the entry from pending
optimized table only if the optimization was triggered through
%OptimizeFunctionOnNextCall / %OptimizeOsr.
3. Adds a check to enforce %PrepareFunctionForOptimize was called.
4. Adds a new run-time flag to only check in the d8 test runner. We
don't want this check enabled in other cases like clusterfuzz that doesn't
ensure %PrepareFunctionForOptimize is called.
Bug: v8:8394, v8:8801, v8:9183
Change-Id: I9ae2b2da812e313c746b6df0b2da864c2ed5de51
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1664810
Commit-Queue: Mythri Alle <mythria@chromium.org>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62653}
In the rare case that a tagged template is not initialized before
optimization time, we currently cache this created template in the
feedback vector. If we stop doing this, we simplify the interface
usefully for concurrent compilation and pay little for it.
Bug: v8:7790
Change-Id: Ifc82b0eb931a706767596febd4f4b312e167fd25
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1690837
Commit-Queue: Michael Stanton <mvstanton@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62590}
In this bug, we might replace a phi node with the Dead node even though
it still has uses. DeadCodeElimination picks this up and inserts a
runtime crash into the code.
Bug: chromium:974474
Change-Id: Iea685913c8666806972719bbfb0891e516207d4f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1669693
Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62352}
We tried to pass the load mode even for stores.
Bug: chromium:977670
Change-Id: I2527a5ca755dba343b75f54383d17e22be0a20a5
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1672940
Auto-Submit: Georg Neis <neis@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62333}
Disable bytecode flushing for test as it messes up lazy source
positions and the flags aren't representative anyway.
Bug: v8:8510
Change-Id: I6d5bc8dcd174a9bfc48f682518e6c62d79acb691
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1658152
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Auto-Submit: Dan Elphick <delphick@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62155}
With bytecode flushing and lazy feedback allocation, we need to call
%PrepareForOptimization before we call %OptimizeFunctionOnNextCall,
ideally after declaring the function.
Bug: v8:8801, v8:8394, v8:9183
Change-Id: I3fb257282a30f6526a376a3afdedb44786320d34
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1648255
Commit-Queue: Mathias Bynens <mathias@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Reviewed-by: Mythri Alle <mythria@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62119}
We need to hold onto the bytecode array so it doesn't get flushed.
Bug: v8:8394
Change-Id: Ia583a0a662740e369fcbc1c94041895e463be26e
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1645329
Commit-Queue: Mythri Alle <mythria@chromium.org>
Auto-Submit: Mythri Alle <mythria@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62011}
Array push / pop / shift were inlined if the elements kind of the
receiver maps is the same. This cl extends it by inlining these
builtins even when the receiver maps have different elements kinds.
It still limits it to only fast elements kinds. This is required to
prevent regressions in deltablue when lazy feedback allocation is
enabled. With lazy feedback allocation we may see polymorphic
feedback more often, since we don't have allocation site feedback
till the feedback vectors are allocated.
Bug: v8:9078
Change-Id: Id4a7b84be6305b125913b6ce0fb4f3eb3e3b15ec
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1632239
Commit-Queue: Mythri Alle <mythria@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61949}
This is a quick fix for the recent bailout-on-uninitialized feature of
the serializer, which does not work with resumables. For now, simply
treat the ResumeGenerator bytecode as if it was an exception handler
entry point. I want to revisit this later because the proper fix might
be to teach the serializer about the SwitchOnGeneratorState bytecode.
Bug: chromium:966560, v8:7790
Change-Id: I48bc6ba7299faa29802159cc7c36f4629667b5d8
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1630670
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Commit-Queue: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61877}
This is a reland of e588ff10e5
The only change over the original CL is found in JSCreateLowering::AllocateFastLiteral. We now guard against boilerplate values for unboxed double fields that *look* like legitimate initial values, but should really be kHoleNanInt64 instead.
The underlying problem certainly existed before, but an invariant added to LoadElimination in this CL caused a Chromium layout test to fail. The change in this reland is therefore a workaround, the root cause remains to be fixed. Specifically, we find that a pointer to the undefined value oddball is sometimes reinterpreted as a double and assigned as a boilerplate value. @jarin suspects that this stems from in-place map updates.
Original change's description:
> Make LoadElimination aware of const fields (Part 2; stores)
>
> Adds const information to store field accesses and uses it in load elimination
>
> Change-Id: I00765c854c95c955dabd78557463267b95f75eef
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1611543
> Reviewed-by: Georg Neis <neis@chromium.org>
> Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
> Commit-Queue: Georg Schmid <gsps@google.com>
> Cr-Commit-Position: refs/heads/master@{#61796}
Change-Id: Ie388754890024a3ca7d10c9d4d7391442655b426
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1630676
Reviewed-by: Georg Neis <neis@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Commit-Queue: Georg Schmid <gsps@google.com>
Cr-Commit-Position: refs/heads/master@{#61838}
Unfortunately, we still have to keep the field because GC mole and Torque
do not support platform specific padding well
(see http://crbug.com/v8/9287).
Bug: v8:9183
Change-Id: I2210be4b8174c97bc82145605f9b862aac3bdc37
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1624791
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Commit-Queue: Jaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61802}
Adds const information to store field accesses and uses it in load elimination
Change-Id: I00765c854c95c955dabd78557463267b95f75eef
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1611543
Reviewed-by: Georg Neis <neis@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Commit-Queue: Georg Schmid <gsps@google.com>
Cr-Commit-Position: refs/heads/master@{#61796}
This is a reland of e7e512da66
Original change's description:
> [turbofan] Add fast path for single-character String#startsWith()
>
> This CL adds a fast path to String#startsWith(s) if s is a
> single character string.
>
> Bug: v8:8400
> Change-Id: Ibd6a9d1e46d98f41c198d2b579208e25003eedb0
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1525362
> Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
> Reviewed-by: Sigurd Schneider <sigurds@chromium.org>
> Commit-Queue: Sigurd Schneider <sigurds@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#61504}
Bug: v8:8400
Change-Id: Ic2d60ccb8fdeb51373fcd025a7e970fda0c14d79
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1618342
Reviewed-by: Sigurd Schneider <sigurds@chromium.org>
Commit-Queue: Sigurd Schneider <sigurds@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61637}
This CL adds a fast path to String#startsWith(s) if s is a
single character string.
Bug: v8:8400
Change-Id: Ibd6a9d1e46d98f41c198d2b579208e25003eedb0
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1525362
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Sigurd Schneider <sigurds@chromium.org>
Commit-Queue: Sigurd Schneider <sigurds@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61504}
We need to keep strong references to the final map, otherwise the test
may start failing randomly depending on GC timing, because the optimized
code will get deoptimized when the map disappears.
Bug: v8:9236
Change-Id: I3c18cba96546020b4d70b95993e1531e787ed253
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1607652
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61438}
This is a reland of 289b25765a.
The fix for failures landed here:
https://chromium-review.googlesource.com/c/v8/v8/+/1599388
Original change's description:
> [Test] Update tests to work with lazy feedback allocation.
>
> This adds either %EnsureFeedbackVectorForFunction or
> %PrepareFunctionForOptimization to allocate feedback vectors when testing
> optimization, allocation sites, IC transitions etc.,
>
> Bug: v8:8394
> Change-Id: I6ad1b6d460e4abda693b326cddb87754e080a0a1
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1593303
> Commit-Queue: Mythri Alle <mythria@chromium.org>
> Auto-Submit: Mythri Alle <mythria@chromium.org>
> Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#61212}
Bug: v8:8394
Change-Id: Idb5bba221d138e6fd73155f959b9e16fc948c709
TBR: rmcilroy@chromium.org
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1599607
Reviewed-by: Mythri Alle <mythria@chromium.org>
Commit-Queue: Mythri Alle <mythria@chromium.org>
Auto-Submit: Mythri Alle <mythria@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61332}
This adds either %EnsureFeedbackVectorForFunction or
%PrepareFunctionForOptimization to allocate feedback vectors when testing
optimization, allocation sites, IC transitions etc.,
Bug: v8:8394
Change-Id: I6ad1b6d460e4abda693b326cddb87754e080a0a1
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1593303
Commit-Queue: Mythri Alle <mythria@chromium.org>
Auto-Submit: Mythri Alle <mythria@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61212}
On Windows, expanding the stack by more than 4 KB at a time can cause
access violations. This change fixes a few known cases (and includes
unit tests for those), and attempts to make stack expansion more
consistent overall by using the AllocateStackSpace helper method
everywhere we can, even when the offset is a small constant.
On arm64, there was already a consistent method for stack pointer
manipulation using the Claim and Drop methods, so Claim is updated to
touch every page.
Bug: v8:9017
Change-Id: I2dbbceeebbdefaf45803e9b621fe83f52234a395
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1570666
Commit-Queue: Seth Brenith <seth.brenith@microsoft.com>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61186}
When asked to start at the receiver and the receiver is a primitive, the
dependency should be taken on the primitive map (which is a no-op)
rather than the wrapper object's map.
Bug: chromium:958716
Change-Id: I9c8b2b56436d134b2f79dbe458c0c527fe6d17a1
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1593086
Commit-Queue: Georg Neis <neis@chromium.org>
Auto-Submit: Georg Neis <neis@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61174}
- Add missing uses of MapInference::NoChange.
- Insert map checks even if inferred maps were reliable, because
they were inferred for an earlier effect input.
Bug: chromium:958420, chromium:958350, v8:9197
Change-Id: Id7677b1fc6f1e09dc12ae178f1155e4245b4e3e6
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1593077
Auto-Submit: Georg Neis <neis@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61157}
This is a reland of 9284ad5731, after
adding a missing speculation mode check in ReduceCallApiFunction.
Original change's description:
> [turbofan] Avoid raw InferReceiverMaps in JSCallReducer
>
> Instead provide an abstraction that makes it hard to forget
> dealing with unreliable maps.
>
> This also fixes a deopt loop in Function.prototype.bind and
> one in Array.prototype.reduce.
>
> Bug: v8:9137
> Change-Id: If6a51182c8693a62e9fb6d302cec19b4d48e25cb
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1578501
> Commit-Queue: Georg Neis <neis@chromium.org>
> Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#61106}
Tbr: jarin@chromium.org
Bug: v8:9137, v8:9197
Change-Id: I0db68d267055969553c0c1b85fad7b909075c062
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1589976
Commit-Queue: Georg Neis <neis@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61140}
This reverts commit 9284ad5731.
Reason for revert: breaks blink tests:
https://ci.chromium.org/p/v8/builders/ci/V8-Blink%20Win/16839
Original change's description:
> [turbofan] Avoid raw InferReceiverMaps in JSCallReducer
>
> Instead provide an abstraction that makes it hard to forget
> dealing with unreliable maps.
>
> This also fixes a deopt loop in Function.prototype.bind and
> one in Array.prototype.reduce.
>
> Bug: v8:9137
> Change-Id: If6a51182c8693a62e9fb6d302cec19b4d48e25cb
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1578501
> Commit-Queue: Georg Neis <neis@chromium.org>
> Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#61106}
TBR=jarin@chromium.org,neis@chromium.org
Change-Id: I97e0f47fb82eda76656905a3f7cc494babd92be6
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:9137
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1588433
Reviewed-by: Sigurd Schneider <sigurds@chromium.org>
Commit-Queue: Sigurd Schneider <sigurds@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61118}
Instead provide an abstraction that makes it hard to forget
dealing with unreliable maps.
This also fixes a deopt loop in Function.prototype.bind and
one in Array.prototype.reduce.
Bug: v8:9137
Change-Id: If6a51182c8693a62e9fb6d302cec19b4d48e25cb
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1578501
Commit-Queue: Georg Neis <neis@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61106}
This enables constant field tracking unconditionally.
TBR=jgruber@chromium.org
Bug: v8:8361
Change-Id: I02f35827d860c3e0f18a3d55cb156c088d48bc94
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1585730
Commit-Queue: Jaroslav Sevcik <jarin@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61055}
This fixes the bounds check for the 'in' operator to handle the negative
index case properly (by using the same machinery as the potentially
out-of-bounds loads/stores use).
Bug: chromium:952586
Change-Id: I2225acae8be7dcedbcde745e8ef202e789085041
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1581179
Reviewed-by: Georg Neis <neis@chromium.org>
Commit-Queue: Jaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#60978}
This adds a new flag --modify-field-representation-inplace (enabled by
default), which lets the runtime perform field representation changes
for Smi to Tagged or for HeapObject to Tagged in-place instead of
creating new maps and marking the previous map tree as deprecated.
That means we create (a lot) fewer Maps and DescriptorArrays in the
beginning and also need to self-heal fewer objects later (migrating
off the deprecated maps). In TurboFan we just take the "field owner
dependency" whenever we use the field representation, which is very
similar to what we already do for the field types. That means if we
change the representation of a field that we used in optimized code,
we will simply deoptimize that code and have TurboFan potentially
later optimize it again with the new field representation.
On the Speedometer2/ElmJS-TodoMVC test, this reduces the total execution
time from around 415ms to around 352ms, which corresponds to a **15%**
improvement. The overall Speedometer2 score improves from around 74.1
to around 78.3 (on local runs with content_shell), corresponding to a
**5.6%** improvement here. 🎉
On the CNN desktop browsing story, it seems that we reduce map space
utilization/fragmentation by about 4-5%. But since we allocate a lot
less (fewer Maps and DescriptorArrays) we also significantly change
the GC timing, which heavily influences the results here. So take this
with a grain of salt. 🤷
Note: For Double fields, this doesn't change anything, meaning they
still create new maps and deprecate the previous map trees.
Bug: v8:8749, v8:8865, v8:9114
Change-Id: Ibd70efcb59be982863905663dbfaa89aa5b31e14
Cq-Include-Trybots: luci.chromium.try:linux-rel,win7-rel
Doc: http://bit.ly/v8-in-place-field-representation-changes
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1565891
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Auto-Submit: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#60822}
... all of the kind that modifies the accumulator but no other
registers. Also move a few of that kind out of the IGNORED_BYTECODES
list, where they didn't belong.
R=mslekova@chromium.org
Bug: v8:7790
Change-Id: I67189750e5e01fc8a3b6b5117b61a0d21837693a
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1561320
Commit-Queue: Georg Neis <neis@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Cr-Commit-Position: refs/heads/master@{#60817}
This reverts commit 1416d5a565.
Reason for revert: blocks roll https://chromium-review.googlesource.com/c/chromium/src/+/1564550
Original change's description:
> [map] Support in-place field representation changes.
>
> This adds a new flag --modify-field-representation-inplace (enabled by
> default), which lets the runtime perform field representation changes
> for Smi to Tagged or for HeapObject to Tagged in-place instead of
> creating new maps and marking the previous map tree as deprecated.
>
> That means we create (a lot) fewer Maps and DescriptorArrays in the
> beginning and also need to self-heal fewer objects later (migrating
> off the deprecated maps). In TurboFan we just take the "field owner
> dependency" whenever we use the field representation, which is very
> similar to what we already do for the field types. That means if we
> change the representation of a field that we used in optimized code,
> we will simply deoptimize that code and have TurboFan potentially
> later optimize it again with the new field representation.
>
> On the Speedometer2/ElmJS-TodoMVC test, this reduces the total execution
> time from around 415ms to around 352ms, which corresponds to a **15%**
> improvement. The overall Speedometer2 score improves from around 74.1
> to around 78.3 (on local runs with content_shell), corresponding to a
> **5.6%** improvement here. 🎉
>
> On the CNN desktop browsing story, it seems that we reduce map space
> utilization/fragmentation by about 4-5%. But since we allocate a lot
> less (fewer Maps and DescriptorArrays) we also significantly change
> the GC timing, which heavily influences the results here. So take this
> with a grain of salt. 🤷♂️
>
> Note: For Double fields, this doesn't change anything, meaning they
> still create new maps and deprecate the previous map trees.
>
> Bug: v8:8749, v8:8865, v8:9114
> Change-Id: I694a53f87ae5caeb868fd98a21809b66d4297d35
> Cq-Include-Trybots: luci.chromium.try:linux-blink-rel
> Doc: http://bit.ly/v8-in-place-field-representation-changes
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1561132
> Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
> Reviewed-by: Igor Sheludko <ishell@chromium.org>
> Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> Reviewed-by: Georg Neis <neis@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#60764}
TBR=jarin@chromium.org,neis@chromium.org,ishell@chromium.org,bmeurer@chromium.org,verwaest@chromium.org
# Not skipping CQ checks because original CL landed > 1 day ago.
Bug: v8:8749, v8:8865, v8:9114
Change-Id: I666975d08d51bbe7ab4faec9428b9a1f88e9b322
Cq-Include-Trybots: luci.chromium.try:linux-blink-rel
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1564208
Reviewed-by: Michael Hablich <hablich@chromium.org>
Commit-Queue: Michael Hablich <hablich@chromium.org>
Cr-Commit-Position: refs/heads/master@{#60807}
The current NumberEqual check ignores -0 when it is stored to
a constant unboxed double field containing 0.
Bug: v8:9113
Change-Id: I7eb59ca8af09ab7317da3c6ce9c9cedad81f6cae
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1561317
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Jaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#60771}
This adds a new flag --modify-field-representation-inplace (enabled by
default), which lets the runtime perform field representation changes
for Smi to Tagged or for HeapObject to Tagged in-place instead of
creating new maps and marking the previous map tree as deprecated.
That means we create (a lot) fewer Maps and DescriptorArrays in the
beginning and also need to self-heal fewer objects later (migrating
off the deprecated maps). In TurboFan we just take the "field owner
dependency" whenever we use the field representation, which is very
similar to what we already do for the field types. That means if we
change the representation of a field that we used in optimized code,
we will simply deoptimize that code and have TurboFan potentially
later optimize it again with the new field representation.
On the Speedometer2/ElmJS-TodoMVC test, this reduces the total execution
time from around 415ms to around 352ms, which corresponds to a **15%**
improvement. The overall Speedometer2 score improves from around 74.1
to around 78.3 (on local runs with content_shell), corresponding to a
**5.6%** improvement here. 🎉
On the CNN desktop browsing story, it seems that we reduce map space
utilization/fragmentation by about 4-5%. But since we allocate a lot
less (fewer Maps and DescriptorArrays) we also significantly change
the GC timing, which heavily influences the results here. So take this
with a grain of salt. 🤷♂️
Note: For Double fields, this doesn't change anything, meaning they
still create new maps and deprecate the previous map trees.
Bug: v8:8749, v8:8865, v8:9114
Change-Id: I694a53f87ae5caeb868fd98a21809b66d4297d35
Cq-Include-Trybots: luci.chromium.try:linux-blink-rel
Doc: http://bit.ly/v8-in-place-field-representation-changes
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1561132
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#60764}
Drive-by fix: In ProcessFeedbackForGlobalAccess, we had forgotten to
return the feedback when it already existed.
Bug: v8:7790, v8:9094
Change-Id: Ie4be6cef5755bbdd9d8ed472caaa2e32d243893d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1554680
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#60705}
- We didn't take stability dependencies on the inferred maps
in case of kUnreliableReceiverMaps.
- We didn't take stability dependencies on the prototype chains.
Bug: v8:9041
Change-Id: I85418dbed219f51e7fb46c59a0cb9cbb9b499bc1
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1541107
Commit-Queue: Georg Neis <neis@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#60550}
It was missing a control output.
Bug: chromium:946889
Change-Id: I85f203fc6e27a60f0b86e0e2999dd798a5416dfc
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1547655
Commit-Queue: Georg Neis <neis@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#60549}
In reducers, we should avoid reductions of the form
ReduceWithValue(node, replacement)
return Replace(node)
because such reduction does not kill the original node, so it may
become subject to resurrection from some side table (in the bug
referenced below it was load elimination's side table). Instead,
we should use
ReduceWithValue(node, replacement)
return Replace(replacement)
Bug: chromium:945644
Change-Id: Id210efe0d214a53241392d30b7f0eee8e7515e2a
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1545229
Reviewed-by: Sigurd Schneider <sigurds@chromium.org>
Commit-Queue: Jaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#60517}
Process feedback and hints for Lda/StaNamed bytecodes w.r.t. access on
the global proxy. This stores the property cells (or their absence) on
the JSGlobalProxyData.
Bug: v8:7790
Change-Id: Iadedea5494611c1b2ed38b6ce75687e084cc27f9
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1499499
Commit-Queue: Jaroslav Sevcik <jarin@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#60411}
ReduceArrayIndexOfIncludes didn't account for kUnreliableReceiverMaps.
Will think about a more robust mechanism for this.
Bug: chromium:944062
Change-Id: Ib2bdaf4399225de4413e12c5684f58dfe524a2cd
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1532331
Commit-Queue: Jaroslav Sevcik <jarin@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#60400}
There were four places where we did essentially the same steps in
order to extract the initial map for inlining a JSCreate operation.
This CL creates a function on NodeProperties for this task.
As a side effect, this fixes a bug in ReduceJSCreateArray, where
has_initial_map could get called when it wasn't permissible to do so.
Notes: For simplicity, in one or two places where we used to get the
target/newtarget constants from the types we now get them from
HeapConstant nodes.
Cosmetic change: rename "receiver_map" to the more accurate
"root_map" in JSNativeContextSpecialization::ExtractReceiverMaps.
Bug: chromium:939316
Change-Id: I8fd9eb50993be3d839ab9b18eeea28184c53eabf
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1528435
Commit-Queue: Georg Neis <neis@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#60301}
If the branch associated with the condition is kDead, the current
node will be killed anyway, so let us just survive the lowering.
Bug: chromium:935092
Change-Id: If7b39e3b5452d6c9bc5199080eb38725e6c4eab5
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1488769
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Commit-Queue: Jaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#60143}
Causes flakyness in TSAN runs when flag is written by EnforceFlagImplications
and read by ConcurrentMarking.
BUG=v8:8924
Change-Id: I2b0bf0fbb678e03492d7ed13e48657de9316b700
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1505796
Auto-Submit: Ross McIlroy <rmcilroy@chromium.org>
Commit-Queue: Mythri Alle <mythria@chromium.org>
Reviewed-by: Mythri Alle <mythria@chromium.org>
Cr-Commit-Position: refs/heads/master@{#60062}
This piggy-backs off similar support for lite mode, which silently skips
tests that require optimization in lite (and now jitless) modes.
Bug: v8:7777,v8:8778, v8:8885
Change-Id: I666d92685ca71682224028743f02d0cce3723135
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1503758
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#60057}
Bytecode flushing can make tests using assertOptimized flaky if the bytecode is
flushed between marking and optimization. It can also be flaky if the feedback vector
is collected before optimization. To prevent this, a new %PrepareForOptimization
runtime-test function is added that hold onto the bytecode strongly until it is
optimized after being explicitly marked for optimization by %OptimizeFunctionOnNextCall.
BUG=v8:8801,v8:8395
Change-Id: Idbd962a3a2044b915903f9c5e92d1789942b5b41
Reviewed-on: https://chromium-review.googlesource.com/c/1463525
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59914}
When calling a known function from optimized code, where the number of
actual arguments does not match the number of expected arguments,
TurboFan has to call indirectly via the arguments adaptor trampoline,
which creates an argument adaptor frame underneath the activation record
for the callee. This is done so that the callee can still get to the
actual arguments, using either
1. the arguments object, or
2. rest parameters (to get to superfluous arguments), or
3. the non-standard Function.arguments accessor (for sloppy mode
functions), or
4. direct eval(), where we don't know whether there's a use of the
arguments object hiding somewhere in the string.
However going through the arguments adaptor trampoline is quite
expensive usually, it seems to be responsible for over 60% of the
call overhead in those cases.
So this adds a fast path for the case of calling strict mode functions
where we have an arguments mismatch, but where we are sure that the
callee cannot observe the actual arguments. We use a bit on the
SharedFunctionInfo to indicate that this is safe, which is controlled
by hints from the Parser which knows whether the callee uses either
arguments object or rest parameters.
In those cases we use a direct call from optimized code, passing the
expected arguments instead of the actual arguments. This improves the
benchmark on the document below by around 60-65%, which is exactly
the overhead of the arguments adaptor trampoline that we save in this
case.
This also adds a runtime flag --fast_calls_with_arguments_mismatches,
which can be used to turn off the new behavior. This might be handy
for checking the performance impact via Finch.
Bug: v8:8895
Change-Id: Idea51dba7ee6cb989e86e0742eaf3516e5afe3c4
Cq-Include-Trybots: luci.chromium.try:linux-blink-rel
Doc: http://bit.ly/v8-faster-calls-with-arguments-mismatch
Reviewed-on: https://chromium-review.googlesource.com/c/1482735
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59825}
