This is for consistency and compiler-enforced type safety. No change
in behavior intended.
Change-Id: I31467832ba6c63fd5f97df9fee6221559b283d67
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1852766
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#64244}
Got rid of the following circular header dependency chains:
compilation-dependencies <-> js-heap-broker <-> access-info
types <-> js-heap-broker <-> access-info
Extracted former CompilationDependencies::Dependency class into its own header.
Extracted *Ref classes into their own header.
This should enable building on older GCC versions, e.g. 5.4.0.
Bug: v8:9440
Change-Id: Ia345bc227d8f7806d0b8622b706346a7ce6d01ea
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1687415
Commit-Queue: Maya Lekova <mslekova@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Reviewed-by: Michael Stanton <mvstanton@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62541}
Instead of recording dependencies during ComputePropertyAccessInfo(s),
store off-the-record dependencies in the resulting PropertyAccessInfo(s)
and record them when the PropertyAccessInfo(s) are consumed. This will
enable us to do the ComputePropertyAccessInfo(s) during serialization.
Bug: v8:7790
Change-Id: I2a3918eb3bc2c795061ca7969c0053b68a53aea7
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1581610
Commit-Queue: Georg Neis <neis@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61051}
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}
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}
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}
- 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}
This merges the check if a protector is intact with the recording of
the dependency on it, at least in many cases.
Also introduce convenience functions to avoid the heap broker clutter.
Change-Id: I35508c4685a2f0df77819bf81075dd14a30e7e4f
Reviewed-on: https://chromium-review.googlesource.com/c/1487491
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@{#59924}
This adds constant field tracking for arrays. To prevent changing the
field in some other elements-kind-branch of transition tree, we only
use the const information in the optimizing compiler if the map is not
an array map or if the map is stable (since stable maps cannot
transition to a different elements-kind-branch without deopt).
Some more details:
https://docs.google.com/document/d/1r2GAvdi_wudDS6iRUfdPw0gxWMfV-IX1PqKgwW47FyE
Bug: chromium:912162, v8:8361
Change-Id: Iea1b2f03ddee16205c2141ac5e813a973dd23cf4
Reviewed-on: https://chromium-review.googlesource.com/c/1454606
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@{#59409}
Remove a DCHECK that got triggered in the rare condition that GC kicks in
during CompilationDependencies::Commit, changing the pretenuring decision,
thus leading to deoptimization. To make sure this rare case is properly
handled, add a new FLAG_pretenure_during_compilation and a cctest that
simulates it predictably.
R=jarin@chromium.org,mvstanton@chromium.org
Bug: v8:8520
Change-Id: If83f8a3d4659a694357b3869c931c7d7c164fd1a
Reviewed-on: https://chromium-review.googlesource.com/c/1363143
Commit-Queue: Maya Lekova <mslekova@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Reviewed-by: Michael Stanton <mvstanton@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58236}
As well as a few other things in JSNativeContextSpecialization.
Bug: v8:7790
Change-Id: Ic13abec45797bb4c6cc66a140180122529c7288d
Reviewed-on: https://chromium-review.googlesource.com/c/1280327
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@{#56670}
Introduce a CompilationDependency that let's us optimize the lookup of
a function's "prototype" property. This is basically the same as
InitialMapDependency, except that if the function's initial map doesn't
exist yet, it is created after compilation.
Bug: v8:7790, chromium:875175
Change-Id: I62834f1815b3cef282fa67e6d64a6ee0e3777929
Reviewed-on: https://chromium-review.googlesource.com/1184714
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#55299}
The idea is to compute the slack before compilation start. Then
we check that the slack tracking decision is the same at the end
of compilation. If it is, we just commit to that slack tracking
(by calling function->CompleteInobjectSlackTrackingIfActive).
If the slack tracking decision changed, we will retry the compilation.
This has several pieces:
- Expose computation of slack and instance size from the object model.
- Add compilation dependency on the slack tracking result.
- Change create lowering to use the dependency.
- Fix array creation to use the slack tracking result's instance
size.
Bug: v8:7790
Change-Id: Id975300cfd6c1786733cd7cbf55cc507c05738b2
Reviewed-on: https://chromium-review.googlesource.com/1164957
Reviewed-by: Georg Neis <neis@chromium.org>
Commit-Queue: Jaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#54982}
We'll soon start collecting data from the JS heap prior to the typed
lowering pass, and then refrain from reading the heap in that pass.
This CL prepares the broker machinery by introducing a hash table that
maps an object (handle) to the corresponding cached data. For the time
being, that cached data is essentially just the handle itself.
Bug: v8:7790
Change-Id: I830e9c72faafb7ae1d10e8a111636b3a3762bbc6
Reviewed-on: https://chromium-review.googlesource.com/1143405
Commit-Queue: Georg Neis <neis@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#54618}
- Move the CompilationDependencies member of OptimizedCompilationInfo
to Turbofan's PipelineData (and thus into the compiler namespace).
- Move compilation-dependencies.{cc,h} to the compiler directory.
Bug: v8:7902
Change-Id: I5471d0923daf83abe975357325db5bc5ad0a8571
Reviewed-on: https://chromium-review.googlesource.com/1127793
Commit-Queue: Georg Neis <neis@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#54295}
