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  1. 11 Nov, 2021 1 commit
  3. 24 Aug, 2021 1 commit
    • Dan Elphick's avatar
      Reland "[include] Split out v8.h" · ec06bb6c
      Dan Elphick authored 
      This is a reland of d1b27019

Fixes include:
Adding missing file to bazel build
Forward-declaring classing before friend-classing them to fix win/gcc
Add missing v8-isolate.h include for vtune builds

Original change's description:
> [include] Split out v8.h
>
> This moves every single class/function out of include/v8.h into a
> separate header in include/, which v8.h then includes so that
> externally nothing appears to have changed.
>
> Every include of v8.h from inside v8 has been changed to a more
> fine-grained include.
>
> Previously inline functions defined at the bottom of v8.h would call
> private non-inline functions in the V8 class. Since that class is now
> in v8-initialization.h and is rarely included (as that would create
> dependency cycles), this is not possible and so those methods have been
> moved out of the V8 class into the namespace v8::api_internal.
>
> None of the previous files in include/ now #include v8.h, which means
> if embedders were relying on this transitive dependency then it will
> give compile failures.
>
> v8-inspector.h does depend on v8-scripts.h for the time being to ensure
> that Chrome continue to compile but that change will be reverted once
> those transitive #includes in chrome are changed to include it directly.
>
> Full design:
> https://docs.google.com/document/d/1rTD--I8hCAr-Rho1WTumZzFKaDpEp0IJ8ejZtk4nJdA/edit?usp=sharing
>
> Bug: v8:11965
> Change-Id: I53b84b29581632710edc80eb11f819c2097a2877
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3097448
> Reviewed-by: Yang Guo <yangguo@chromium.org>
> Reviewed-by: Camillo Bruni <cbruni@chromium.org>
> Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
> Reviewed-by: Leszek Swirski <leszeks@chromium.org>
> Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
> Commit-Queue: Dan Elphick <delphick@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#76424}

Cq-Include-Trybots: luci.v8.try:v8_linux_vtunejit
Bug: v8:11965
Change-Id: I99f5d3a73bf8fe25b650adfaf9567dc4e44a09e6
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3113629Reviewed-by: 's avatarLeszek Swirski <leszeks@chromium.org>
Reviewed-by: 's avatarCamillo Bruni <cbruni@chromium.org>
Reviewed-by: 's avatarMichael Lippautz <mlippautz@chromium.org>
Reviewed-by: 's avatarJakob Kummerow <jkummerow@chromium.org>
Reviewed-by: 's avatarSimon Zünd <szuend@chromium.org>
Commit-Queue: Dan Elphick <delphick@chromium.org>
Cr-Commit-Position: refs/heads/main@{#76460}
      ec06bb6c
  5. 23 Aug, 2021 2 commits
    • Dan Elphick's avatar
      Revert "[include] Split out v8.h" · 44fe02ce
      Dan Elphick authored 
      This reverts commit d1b27019.

Reason for revert: Broke vtune build, tsan build and possibly others

Original change's description:
> [include] Split out v8.h
>
> This moves every single class/function out of include/v8.h into a
> separate header in include/, which v8.h then includes so that
> externally nothing appears to have changed.
>
> Every include of v8.h from inside v8 has been changed to a more
> fine-grained include.
>
> Previously inline functions defined at the bottom of v8.h would call
> private non-inline functions in the V8 class. Since that class is now
> in v8-initialization.h and is rarely included (as that would create
> dependency cycles), this is not possible and so those methods have been
> moved out of the V8 class into the namespace v8::api_internal.
>
> None of the previous files in include/ now #include v8.h, which means
> if embedders were relying on this transitive dependency then it will
> give compile failures.
>
> v8-inspector.h does depend on v8-scripts.h for the time being to ensure
> that Chrome continue to compile but that change will be reverted once
> those transitive #includes in chrome are changed to include it directly.
>
> Full design:
> https://docs.google.com/document/d/1rTD--I8hCAr-Rho1WTumZzFKaDpEp0IJ8ejZtk4nJdA/edit?usp=sharing
>
> Bug: v8:11965
> Change-Id: I53b84b29581632710edc80eb11f819c2097a2877
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3097448
> Reviewed-by: Yang Guo <yangguo@chromium.org>
> Reviewed-by: Camillo Bruni <cbruni@chromium.org>
> Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
> Reviewed-by: Leszek Swirski <leszeks@chromium.org>
> Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
> Commit-Queue: Dan Elphick <delphick@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#76424}

Bug: v8:11965
Change-Id: Id57313ae992e720c8b19abc975cd69729e1344aa
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3113627
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Owners-Override: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/main@{#76428}
      44fe02ce
    • Dan Elphick's avatar
      [include] Split out v8.h · d1b27019
      Dan Elphick authored 
      This moves every single class/function out of include/v8.h into a
separate header in include/, which v8.h then includes so that
externally nothing appears to have changed.

Every include of v8.h from inside v8 has been changed to a more
fine-grained include.

Previously inline functions defined at the bottom of v8.h would call
private non-inline functions in the V8 class. Since that class is now
in v8-initialization.h and is rarely included (as that would create
dependency cycles), this is not possible and so those methods have been
moved out of the V8 class into the namespace v8::api_internal.

None of the previous files in include/ now #include v8.h, which means
if embedders were relying on this transitive dependency then it will
give compile failures.

v8-inspector.h does depend on v8-scripts.h for the time being to ensure
that Chrome continue to compile but that change will be reverted once
those transitive #includes in chrome are changed to include it directly.

Full design:
https://docs.google.com/document/d/1rTD--I8hCAr-Rho1WTumZzFKaDpEp0IJ8ejZtk4nJdA/edit?usp=sharing

Bug: v8:11965
Change-Id: I53b84b29581632710edc80eb11f819c2097a2877
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3097448Reviewed-by: 's avatarYang Guo <yangguo@chromium.org>
Reviewed-by: 's avatarCamillo Bruni <cbruni@chromium.org>
Reviewed-by: 's avatarJakob Kummerow <jkummerow@chromium.org>
Reviewed-by: 's avatarLeszek Swirski <leszeks@chromium.org>
Reviewed-by: 's avatarMichael Lippautz <mlippautz@chromium.org>
Commit-Queue: Dan Elphick <delphick@chromium.org>
Cr-Commit-Position: refs/heads/main@{#76424}
      d1b27019
  7. 22 Jun, 2021 1 commit
  9. 09 Feb, 2021 1 commit
  11. 01 Dec, 2020 1 commit
  13. 30 Nov, 2020 1 commit
  15. 26 Nov, 2020 1 commit
  17. 09 Oct, 2020 1 commit
    • Mythri A's avatar
      [handles] Fix is_identical_to to correctly work with Smis · 1f858b3f
      Mythri A authored 
      HandleBase::is_identical_to() is_identical_to in handle base is used to
do the exact comparison by just comparing the locations. When the
locations are different the values are compared. For Smis it
compares 64 bits which might lead to incorrect behaviour. Smis loaded as
a TaggedField has the root address added. It is expexted that we don't
use higher order bits on Smi. Hence, is_identical_to shouldn't use these
bits when comparing Smis. This cl fixes it by comparing the objects
created from the given location. That takes care of correctly comparing
the required bits.

Change-Id: I574dfbea4c1fffc7a9e3a6a10ad7631d40c518ce
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2461743
Commit-Queue: Mythri Alle <mythria@chromium.org>
Reviewed-by: 's avatarIgor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#70422}
      1f858b3f
  19. 08 Oct, 2020 1 commit
    • Leszek Swirski's avatar
      [serializer] Introduce HandleScopes for object contents · c212d10d
      Leszek Swirski authored 
      Create a HandleScope when serializing an object's contents, to reduce
the number of live handles during serialization. There's only a couple
of cases where these handles have to outlive the serialized contents,
and for these cases we introduce GlobalHandleVector or similar manual
strong root mechanisms.

In particular, backrefs don't actually need to exist as a handle vector
(the object addresses are already referred to by the reference map's
IdentityMap), except for DCHECKs, so this becomes a DEBUG-only global
handle vector.

To support this manual strong-rooting, the HotObjectList is split up
into a strong-rooted find-only class in Serializer, and a Handle
vector in Deserializer.

Bug: chromium:1075999
Change-Id: I586eeeb543e3f6c934c168961b068f2c34e72456
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2449980Reviewed-by: 's avatarUlan Degenbaev <ulan@chromium.org>
Reviewed-by: 's avatarJakob Gruber <jgruber@chromium.org>
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#70411}
      c212d10d
  21. 07 Oct, 2020 1 commit
    • Leszek Swirski's avatar
      Reland^4 "[serializer] Allocate during deserialization" · 3c508b38
      Leszek Swirski authored 
      This relands commit 3f4e9bbe.
which was a reland of c4a062a9
which was a reland of 28a30c57
which was a reland of 5d7a29c9

The change had an issue that embedders implementing heap tracing (e.g.
Unified Heap with Blink) could be passed an uninitialized pointer if
marking happened during deserialization of an object containing such a
pointer. Because of the 0xdeadbed0 uninitialized filler value, these
embedders would then receive the value 0xdeadbed0deadbed0 as the
'pointer', and crash on dereference.

There is, however, special handling already for null pointers in heap
tracing, also for dealing with not-yet initialized values. So, we can
make the uninitialized Smi filler be 0x00000000, and that will make such
embedded fields have a nullptr representation, making them follow the
normal uninitialized value bailouts.

In addition, it relands the following dependent changes, which are
relanding unchanged and are followup performance improvements.
Relanding them in the same change should allow for cleaner reverts
should they be needed.

This relands commit 76ad3ab5
[identity-map] Change resize heuristic

This relands commit 77cc96aa
[identity-map] Cache the calculated Hash

This relands commit bee5b996
[serializer] Remove Deserializer::Initialize

This relands commit c8f73f22
[serializer] Cache instance type in PostProcessNewObject

This relands commit 4e7c99ab
[identity-map] Remove double-lookups in IdentityMap

Original change's description:
> Reland^3 "[serializer] Allocate during deserialization"
>
> This is a reland of c4a062a9
> which was a reland of 28a30c57
> which was a reland of 5d7a29c9
>
> Fixes TSAN errors from non-atomic writes in the deserializer. Now all
> writes are (relaxed) atomic.
>
> Original change's description:
> > Reland^2 "[serializer] Allocate during deserialization"
> >
> > This is a reland of 28a30c57
> > which was a reland of 5d7a29c9
> >
> > The crashes were from calling RegisterDeserializerFinished on a null
> > Isolate pointer, for a deserializer that was never initialised
> > (specifically, ReadOnlyDeserializer when ROHeap is shared).
> >
> > Original change's description:
> > > Reland "[serializer] Allocate during deserialization"
> > >
> > > This is a reland of 5d7a29c9
> > >
> > > This reland shuffles around the order of checks in Heap::AllocateRawWith
> > > to not check the new space addresses until it's known that this is a new
> > > space allocation. This fixes an UBSan failure during read-only space
> > > deserialization, which happens before the new space is initialized.
> > >
> > > It also fixes some issues discovered by --stress-snapshot, around
> > > serializing ThinStrings (which are now elided as part of serialization),
> > > handle counts (I bumped the maximum handle count in that check), and
> > > clearing map transitions (the map backpointer field needed a Smi
> > > uninitialized value check).
> > >
> > > Original change's description:
> > > > [serializer] Allocate during deserialization
> > > >
> > > > This patch removes the concept of reservations and a specialized
> > > > deserializer allocator, and instead makes the deserializer allocate
> > > > directly with the Heap's Allocate method.
> > > >
> > > > The major consequence of this is that the GC can now run during
> > > > deserialization, which means that:
> > > >
> > > >   a) Deserialized objects are visible to the GC, and
> > > >   b) Objects that the deserializer/deserialized objects point to can
> > > >      move.
> > > >
> > > > Point a) is mostly not a problem due to previous work in making
> > > > deserialized objects "GC valid", i.e. making sure that they have a valid
> > > > size before any subsequent allocation/safepoint. We now additionally
> > > > have to initialize the allocated space with a valid tagged value -- this
> > > > is a magic Smi value to keep "uninitialized" checks simple.
> > > >
> > > > Point b) is solved by Handlifying the deserializer. This involves
> > > > changing any vectors of objects into vectors of Handles, and any object
> > > > keyed map into an IdentityMap (we can't use Handles as keys because
> > > > the object's address is no longer a stable hash).
> > > >
> > > > Back-references can no longer be direct chunk offsets, so instead the
> > > > deserializer stores a Handle to each deserialized object, and the
> > > > backreference is an index into this handle array. This encoding could
> > > > be optimized in the future with e.g. a second pass over the serialized
> > > > array which emits a different bytecode for objects that are and aren't
> > > > back-referenced.
> > > >
> > > > Additionally, the slot-walk over objects to initialize them can no
> > > > longer use absolute slot offsets, as again an object may move and its
> > > > slot address would become invalid. Now, slots are walked as relative
> > > > offsets to a Handle to the object, or as absolute slots for the case of
> > > > root pointers. A concept of "slot accessor" is introduced to share the
> > > > code between these two modes, and writing the slot (including write
> > > > barriers) is abstracted into this accessor.
> > > >
> > > > Finally, the Code body walk is modified to deserialize all objects
> > > > referred to by RelocInfos before doing the RelocInfo walk itself. This
> > > > is because RelocInfoIterator uses raw pointers, so we cannot allocate
> > > > during a RelocInfo walk.
> > > >
> > > > As a drive-by, the VariableRawData bytecode is tweaked to use tagged
> > > > size rather than byte size -- the size is expected to be tagged-aligned
> > > > anyway, so now we get an extra few bits in the size encoding.
> > > >
> > > > Bug: chromium:1075999
> > > > Change-Id: I672c42f553f2669888cc5e35d692c1b8ece1845e
> > > > Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2404451
> > > > Commit-Queue: Leszek Swirski <leszeks@chromium.org>
> > > > Reviewed-by: Jakob Gruber <jgruber@chromium.org>
> > > > Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> > > > Cr-Commit-Position: refs/heads/master@{#70229}

Bug: chromium:1075999
Change-Id: Ib514a4ef16bd02bfb60d046ecbf8fae1ead64a98
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2452689
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: 's avatarUlan Degenbaev <ulan@chromium.org>
Reviewed-by: 's avatarJakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#70366}
      3c508b38
  23. 05 Oct, 2020 1 commit
    • Adam Klein's avatar
      Revert "Reland^3 "[serializer] Allocate during deserialization"" · a10ec2be
      Adam Klein authored 
      This reverts commit 3f4e9bbe, along
with the following dependent changes (reverted to make this a clean revert):
76ad3ab5 [identity-map] Change resize heuristic
77cc96aa [identity-map] Cache the calculated Hash
bee5b996 [serializer] Remove Deserializer::Initialize
c8f73f22 [serializer] Cache instance type in PostProcessNewObject
4e7c99ab [identity-map] Remove double-lookups in IdentityMap

Reason for revert: major crash spike on Canary (https://crbug.com/1135027)

Original change's description:
> Reland^3 "[serializer] Allocate during deserialization"
>
> This is a reland of c4a062a9
> which was a reland of 28a30c57
> which was a reland of 5d7a29c9
>
> Fixes TSAN errors from non-atomic writes in the deserializer. Now all
> writes are (relaxed) atomic.
>
> Original change's description:
> > Reland^2 "[serializer] Allocate during deserialization"
> >
> > This is a reland of 28a30c57
> > which was a reland of 5d7a29c9
> >
> > The crashes were from calling RegisterDeserializerFinished on a null
> > Isolate pointer, for a deserializer that was never initialised
> > (specifically, ReadOnlyDeserializer when ROHeap is shared).
> >
> > Original change's description:
> > > Reland "[serializer] Allocate during deserialization"
> > >
> > > This is a reland of 5d7a29c9
> > >
> > > This reland shuffles around the order of checks in Heap::AllocateRawWith
> > > to not check the new space addresses until it's known that this is a new
> > > space allocation. This fixes an UBSan failure during read-only space
> > > deserialization, which happens before the new space is initialized.
> > >
> > > It also fixes some issues discovered by --stress-snapshot, around
> > > serializing ThinStrings (which are now elided as part of serialization),
> > > handle counts (I bumped the maximum handle count in that check), and
> > > clearing map transitions (the map backpointer field needed a Smi
> > > uninitialized value check).
> > >
> > > Original change's description:
> > > > [serializer] Allocate during deserialization
> > > >
> > > > This patch removes the concept of reservations and a specialized
> > > > deserializer allocator, and instead makes the deserializer allocate
> > > > directly with the Heap's Allocate method.
> > > >
> > > > The major consequence of this is that the GC can now run during
> > > > deserialization, which means that:
> > > >
> > > >   a) Deserialized objects are visible to the GC, and
> > > >   b) Objects that the deserializer/deserialized objects point to can
> > > >      move.
> > > >
> > > > Point a) is mostly not a problem due to previous work in making
> > > > deserialized objects "GC valid", i.e. making sure that they have a valid
> > > > size before any subsequent allocation/safepoint. We now additionally
> > > > have to initialize the allocated space with a valid tagged value -- this
> > > > is a magic Smi value to keep "uninitialized" checks simple.
> > > >
> > > > Point b) is solved by Handlifying the deserializer. This involves
> > > > changing any vectors of objects into vectors of Handles, and any object
> > > > keyed map into an IdentityMap (we can't use Handles as keys because
> > > > the object's address is no longer a stable hash).
> > > >
> > > > Back-references can no longer be direct chunk offsets, so instead the
> > > > deserializer stores a Handle to each deserialized object, and the
> > > > backreference is an index into this handle array. This encoding could
> > > > be optimized in the future with e.g. a second pass over the serialized
> > > > array which emits a different bytecode for objects that are and aren't
> > > > back-referenced.
> > > >
> > > > Additionally, the slot-walk over objects to initialize them can no
> > > > longer use absolute slot offsets, as again an object may move and its
> > > > slot address would become invalid. Now, slots are walked as relative
> > > > offsets to a Handle to the object, or as absolute slots for the case of
> > > > root pointers. A concept of "slot accessor" is introduced to share the
> > > > code between these two modes, and writing the slot (including write
> > > > barriers) is abstracted into this accessor.
> > > >
> > > > Finally, the Code body walk is modified to deserialize all objects
> > > > referred to by RelocInfos before doing the RelocInfo walk itself. This
> > > > is because RelocInfoIterator uses raw pointers, so we cannot allocate
> > > > during a RelocInfo walk.
> > > >
> > > > As a drive-by, the VariableRawData bytecode is tweaked to use tagged
> > > > size rather than byte size -- the size is expected to be tagged-aligned
> > > > anyway, so now we get an extra few bits in the size encoding.
> > > >
> > > > Bug: chromium:1075999
> > > > Change-Id: I672c42f553f2669888cc5e35d692c1b8ece1845e
> > > > Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2404451
> > > > Commit-Queue: Leszek Swirski <leszeks@chromium.org>
> > > > Reviewed-by: Jakob Gruber <jgruber@chromium.org>
> > > > Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> > > > Cr-Commit-Position: refs/heads/master@{#70229}
> > >
> > > Bug: chromium:1075999
> > > Change-Id: Ibc77cc48b3440b4a28b09746cfc47e50c340ce54
> > > Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2440828
> > > Commit-Queue: Leszek Swirski <leszeks@chromium.org>
> > > Auto-Submit: Leszek Swirski <leszeks@chromium.org>
> > > Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> > > Reviewed-by: Jakob Gruber <jgruber@chromium.org>
> > > Cr-Commit-Position: refs/heads/master@{#70267}
> >
> > Tbr: jgruber@chromium.org,ulan@chromium.org
> > Bug: chromium:1075999
> > Change-Id: Iaa8dc54895866ada0e34a7c9e8fff9ae1cb13f2d
> > Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2444991
> > Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> > Commit-Queue: Leszek Swirski <leszeks@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#70279}
>
> Tbr: jgruber@chromium.org,ulan@chromium.org
> Cq-Include-Trybots: luci.v8.try:v8_linux64_tsan_rel_ng,v8_linux64_tsan_no_cm_rel_ng,v8_linux64_tsan_isolates_rel_ng
> Bug: chromium:1075999
> Change-Id: I0b9b11644aebc4cc8b07c62a0f765b24e4d73d89
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2445872
> Commit-Queue: Leszek Swirski <leszeks@chromium.org>
> Auto-Submit: Leszek Swirski <leszeks@chromium.org>
> Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#70288}

TBR=ulan@chromium.org,jgruber@chromium.org,leszeks@chromium.org,dinfuehr@chromium.org

Bug: chromium:1075999, chromium:1135027
Change-Id: I5d0d9e49c0302d94ff7291834f5f18e7a0839eb7
Cq-Include-Trybots: luci.v8.try:v8_linux64_tsan_rel_ng,v8_linux64_tsan_no_cm_rel_ng,v8_linux64_tsan_isolates_rel_ng
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2451030Reviewed-by: 's avatarAdam Klein <adamk@chromium.org>
Commit-Queue: Adam Klein <adamk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#70328}
      a10ec2be
  25. 02 Oct, 2020 3 commits
    • Leszek Swirski's avatar
      Reland^3 "[serializer] Allocate during deserialization" · 3f4e9bbe
      Leszek Swirski authored 
      This is a reland of c4a062a9
which was a reland of 28a30c57
which was a reland of 5d7a29c9

Fixes TSAN errors from non-atomic writes in the deserializer. Now all
writes are (relaxed) atomic.

Original change's description:
> Reland^2 "[serializer] Allocate during deserialization"
>
> This is a reland of 28a30c57
> which was a reland of 5d7a29c9
>
> The crashes were from calling RegisterDeserializerFinished on a null
> Isolate pointer, for a deserializer that was never initialised
> (specifically, ReadOnlyDeserializer when ROHeap is shared).
>
> Original change's description:
> > Reland "[serializer] Allocate during deserialization"
> >
> > This is a reland of 5d7a29c9
> >
> > This reland shuffles around the order of checks in Heap::AllocateRawWith
> > to not check the new space addresses until it's known that this is a new
> > space allocation. This fixes an UBSan failure during read-only space
> > deserialization, which happens before the new space is initialized.
> >
> > It also fixes some issues discovered by --stress-snapshot, around
> > serializing ThinStrings (which are now elided as part of serialization),
> > handle counts (I bumped the maximum handle count in that check), and
> > clearing map transitions (the map backpointer field needed a Smi
> > uninitialized value check).
> >
> > Original change's description:
> > > [serializer] Allocate during deserialization
> > >
> > > This patch removes the concept of reservations and a specialized
> > > deserializer allocator, and instead makes the deserializer allocate
> > > directly with the Heap's Allocate method.
> > >
> > > The major consequence of this is that the GC can now run during
> > > deserialization, which means that:
> > >
> > >   a) Deserialized objects are visible to the GC, and
> > >   b) Objects that the deserializer/deserialized objects point to can
> > >      move.
> > >
> > > Point a) is mostly not a problem due to previous work in making
> > > deserialized objects "GC valid", i.e. making sure that they have a valid
> > > size before any subsequent allocation/safepoint. We now additionally
> > > have to initialize the allocated space with a valid tagged value -- this
> > > is a magic Smi value to keep "uninitialized" checks simple.
> > >
> > > Point b) is solved by Handlifying the deserializer. This involves
> > > changing any vectors of objects into vectors of Handles, and any object
> > > keyed map into an IdentityMap (we can't use Handles as keys because
> > > the object's address is no longer a stable hash).
> > >
> > > Back-references can no longer be direct chunk offsets, so instead the
> > > deserializer stores a Handle to each deserialized object, and the
> > > backreference is an index into this handle array. This encoding could
> > > be optimized in the future with e.g. a second pass over the serialized
> > > array which emits a different bytecode for objects that are and aren't
> > > back-referenced.
> > >
> > > Additionally, the slot-walk over objects to initialize them can no
> > > longer use absolute slot offsets, as again an object may move and its
> > > slot address would become invalid. Now, slots are walked as relative
> > > offsets to a Handle to the object, or as absolute slots for the case of
> > > root pointers. A concept of "slot accessor" is introduced to share the
> > > code between these two modes, and writing the slot (including write
> > > barriers) is abstracted into this accessor.
> > >
> > > Finally, the Code body walk is modified to deserialize all objects
> > > referred to by RelocInfos before doing the RelocInfo walk itself. This
> > > is because RelocInfoIterator uses raw pointers, so we cannot allocate
> > > during a RelocInfo walk.
> > >
> > > As a drive-by, the VariableRawData bytecode is tweaked to use tagged
> > > size rather than byte size -- the size is expected to be tagged-aligned
> > > anyway, so now we get an extra few bits in the size encoding.
> > >
> > > Bug: chromium:1075999
> > > Change-Id: I672c42f553f2669888cc5e35d692c1b8ece1845e
> > > Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2404451
> > > Commit-Queue: Leszek Swirski <leszeks@chromium.org>
> > > Reviewed-by: Jakob Gruber <jgruber@chromium.org>
> > > Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> > > Cr-Commit-Position: refs/heads/master@{#70229}
> >
> > Bug: chromium:1075999
> > Change-Id: Ibc77cc48b3440b4a28b09746cfc47e50c340ce54
> > Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2440828
> > Commit-Queue: Leszek Swirski <leszeks@chromium.org>
> > Auto-Submit: Leszek Swirski <leszeks@chromium.org>
> > Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> > Reviewed-by: Jakob Gruber <jgruber@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#70267}
>
> Tbr: jgruber@chromium.org,ulan@chromium.org
> Bug: chromium:1075999
> Change-Id: Iaa8dc54895866ada0e34a7c9e8fff9ae1cb13f2d
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2444991
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Commit-Queue: Leszek Swirski <leszeks@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#70279}

Tbr: jgruber@chromium.org,ulan@chromium.org
Cq-Include-Trybots: luci.v8.try:v8_linux64_tsan_rel_ng,v8_linux64_tsan_no_cm_rel_ng,v8_linux64_tsan_isolates_rel_ng
Bug: chromium:1075999
Change-Id: I0b9b11644aebc4cc8b07c62a0f765b24e4d73d89
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2445872
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Auto-Submit: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: 's avatarDominik Inführ <dinfuehr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#70288}
      3f4e9bbe
    • Clemens Backes's avatar
      Revert "Reland^2 "[serializer] Allocate during deserialization"" · a81da102
      Clemens Backes authored 
      This reverts commit c4a062a9.

Reason for revert: TSan issues: https://ci.chromium.org/p/v8/builders/ci/V8%20Linux64%20TSAN/33504

Original change's description:
> Reland^2 "[serializer] Allocate during deserialization"
>
> This is a reland of 28a30c57
> which was a reland of 5d7a29c9
>
> The crashes were from calling RegisterDeserializerFinished on a null
> Isolate pointer, for a deserializer that was never initialised
> (specifically, ReadOnlyDeserializer when ROHeap is shared).
>
> Original change's description:
> > Reland "[serializer] Allocate during deserialization"
> >
> > This is a reland of 5d7a29c9
> >
> > This reland shuffles around the order of checks in Heap::AllocateRawWith
> > to not check the new space addresses until it's known that this is a new
> > space allocation. This fixes an UBSan failure during read-only space
> > deserialization, which happens before the new space is initialized.
> >
> > It also fixes some issues discovered by --stress-snapshot, around
> > serializing ThinStrings (which are now elided as part of serialization),
> > handle counts (I bumped the maximum handle count in that check), and
> > clearing map transitions (the map backpointer field needed a Smi
> > uninitialized value check).
> >
> > Original change's description:
> > > [serializer] Allocate during deserialization
> > >
> > > This patch removes the concept of reservations and a specialized
> > > deserializer allocator, and instead makes the deserializer allocate
> > > directly with the Heap's Allocate method.
> > >
> > > The major consequence of this is that the GC can now run during
> > > deserialization, which means that:
> > >
> > >   a) Deserialized objects are visible to the GC, and
> > >   b) Objects that the deserializer/deserialized objects point to can
> > >      move.
> > >
> > > Point a) is mostly not a problem due to previous work in making
> > > deserialized objects "GC valid", i.e. making sure that they have a valid
> > > size before any subsequent allocation/safepoint. We now additionally
> > > have to initialize the allocated space with a valid tagged value -- this
> > > is a magic Smi value to keep "uninitialized" checks simple.
> > >
> > > Point b) is solved by Handlifying the deserializer. This involves
> > > changing any vectors of objects into vectors of Handles, and any object
> > > keyed map into an IdentityMap (we can't use Handles as keys because
> > > the object's address is no longer a stable hash).
> > >
> > > Back-references can no longer be direct chunk offsets, so instead the
> > > deserializer stores a Handle to each deserialized object, and the
> > > backreference is an index into this handle array. This encoding could
> > > be optimized in the future with e.g. a second pass over the serialized
> > > array which emits a different bytecode for objects that are and aren't
> > > back-referenced.
> > >
> > > Additionally, the slot-walk over objects to initialize them can no
> > > longer use absolute slot offsets, as again an object may move and its
> > > slot address would become invalid. Now, slots are walked as relative
> > > offsets to a Handle to the object, or as absolute slots for the case of
> > > root pointers. A concept of "slot accessor" is introduced to share the
> > > code between these two modes, and writing the slot (including write
> > > barriers) is abstracted into this accessor.
> > >
> > > Finally, the Code body walk is modified to deserialize all objects
> > > referred to by RelocInfos before doing the RelocInfo walk itself. This
> > > is because RelocInfoIterator uses raw pointers, so we cannot allocate
> > > during a RelocInfo walk.
> > >
> > > As a drive-by, the VariableRawData bytecode is tweaked to use tagged
> > > size rather than byte size -- the size is expected to be tagged-aligned
> > > anyway, so now we get an extra few bits in the size encoding.
> > >
> > > Bug: chromium:1075999
> > > Change-Id: I672c42f553f2669888cc5e35d692c1b8ece1845e
> > > Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2404451
> > > Commit-Queue: Leszek Swirski <leszeks@chromium.org>
> > > Reviewed-by: Jakob Gruber <jgruber@chromium.org>
> > > Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> > > Cr-Commit-Position: refs/heads/master@{#70229}
> >
> > Bug: chromium:1075999
> > Change-Id: Ibc77cc48b3440b4a28b09746cfc47e50c340ce54
> > Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2440828
> > Commit-Queue: Leszek Swirski <leszeks@chromium.org>
> > Auto-Submit: Leszek Swirski <leszeks@chromium.org>
> > Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> > Reviewed-by: Jakob Gruber <jgruber@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#70267}
>
> Tbr: jgruber@chromium.org,ulan@chromium.org
> Bug: chromium:1075999
> Change-Id: Iaa8dc54895866ada0e34a7c9e8fff9ae1cb13f2d
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2444991
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Commit-Queue: Leszek Swirski <leszeks@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#70279}

TBR=ulan@chromium.org,jgruber@chromium.org,leszeks@chromium.org

Change-Id: Ib2f01db4cd9b55639d6a4af971bda865edb45e84
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: chromium:1075999
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2445250Reviewed-by: 's avatarClemens Backes <clemensb@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#70280}
      a81da102
    • Leszek Swirski's avatar
      Reland^2 "[serializer] Allocate during deserialization" · c4a062a9
      Leszek Swirski authored 
      This is a reland of 28a30c57
which was a reland of 5d7a29c9

The crashes were from calling RegisterDeserializerFinished on a null
Isolate pointer, for a deserializer that was never initialised
(specifically, ReadOnlyDeserializer when ROHeap is shared).

Original change's description:
> Reland "[serializer] Allocate during deserialization"
>
> This is a reland of 5d7a29c9
>
> This reland shuffles around the order of checks in Heap::AllocateRawWith
> to not check the new space addresses until it's known that this is a new
> space allocation. This fixes an UBSan failure during read-only space
> deserialization, which happens before the new space is initialized.
>
> It also fixes some issues discovered by --stress-snapshot, around
> serializing ThinStrings (which are now elided as part of serialization),
> handle counts (I bumped the maximum handle count in that check), and
> clearing map transitions (the map backpointer field needed a Smi
> uninitialized value check).
>
> Original change's description:
> > [serializer] Allocate during deserialization
> >
> > This patch removes the concept of reservations and a specialized
> > deserializer allocator, and instead makes the deserializer allocate
> > directly with the Heap's Allocate method.
> >
> > The major consequence of this is that the GC can now run during
> > deserialization, which means that:
> >
> >   a) Deserialized objects are visible to the GC, and
> >   b) Objects that the deserializer/deserialized objects point to can
> >      move.
> >
> > Point a) is mostly not a problem due to previous work in making
> > deserialized objects "GC valid", i.e. making sure that they have a valid
> > size before any subsequent allocation/safepoint. We now additionally
> > have to initialize the allocated space with a valid tagged value -- this
> > is a magic Smi value to keep "uninitialized" checks simple.
> >
> > Point b) is solved by Handlifying the deserializer. This involves
> > changing any vectors of objects into vectors of Handles, and any object
> > keyed map into an IdentityMap (we can't use Handles as keys because
> > the object's address is no longer a stable hash).
> >
> > Back-references can no longer be direct chunk offsets, so instead the
> > deserializer stores a Handle to each deserialized object, and the
> > backreference is an index into this handle array. This encoding could
> > be optimized in the future with e.g. a second pass over the serialized
> > array which emits a different bytecode for objects that are and aren't
> > back-referenced.
> >
> > Additionally, the slot-walk over objects to initialize them can no
> > longer use absolute slot offsets, as again an object may move and its
> > slot address would become invalid. Now, slots are walked as relative
> > offsets to a Handle to the object, or as absolute slots for the case of
> > root pointers. A concept of "slot accessor" is introduced to share the
> > code between these two modes, and writing the slot (including write
> > barriers) is abstracted into this accessor.
> >
> > Finally, the Code body walk is modified to deserialize all objects
> > referred to by RelocInfos before doing the RelocInfo walk itself. This
> > is because RelocInfoIterator uses raw pointers, so we cannot allocate
> > during a RelocInfo walk.
> >
> > As a drive-by, the VariableRawData bytecode is tweaked to use tagged
> > size rather than byte size -- the size is expected to be tagged-aligned
> > anyway, so now we get an extra few bits in the size encoding.
> >
> > Bug: chromium:1075999
> > Change-Id: I672c42f553f2669888cc5e35d692c1b8ece1845e
> > Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2404451
> > Commit-Queue: Leszek Swirski <leszeks@chromium.org>
> > Reviewed-by: Jakob Gruber <jgruber@chromium.org>
> > Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#70229}
>
> Bug: chromium:1075999
> Change-Id: Ibc77cc48b3440b4a28b09746cfc47e50c340ce54
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2440828
> Commit-Queue: Leszek Swirski <leszeks@chromium.org>
> Auto-Submit: Leszek Swirski <leszeks@chromium.org>
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Reviewed-by: Jakob Gruber <jgruber@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#70267}

Tbr: jgruber@chromium.org,ulan@chromium.org
Bug: chromium:1075999
Change-Id: Iaa8dc54895866ada0e34a7c9e8fff9ae1cb13f2d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2444991Reviewed-by: 's avatarUlan Degenbaev <ulan@chromium.org>
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#70279}
      c4a062a9
  27. 01 Oct, 2020 2 commits
    • Zhi An Ng's avatar
      Revert "Reland "[serializer] Allocate during deserialization"" · c7c0e790
      Zhi An Ng authored 
      This reverts commit 28a30c57.

Reason for revert: Broke Test262 https://ci.chromium.org/p/v8/builders/ci/V8%20Linux%20-%20shared/38638?

Original change's description:
> Reland "[serializer] Allocate during deserialization"
>
> This is a reland of 5d7a29c9
>
> This reland shuffles around the order of checks in Heap::AllocateRawWith
> to not check the new space addresses until it's known that this is a new
> space allocation. This fixes an UBSan failure during read-only space
> deserialization, which happens before the new space is initialized.
>
> It also fixes some issues discovered by --stress-snapshot, around
> serializing ThinStrings (which are now elided as part of serialization),
> handle counts (I bumped the maximum handle count in that check), and
> clearing map transitions (the map backpointer field needed a Smi
> uninitialized value check).
>
> Original change's description:
> > [serializer] Allocate during deserialization
> >
> > This patch removes the concept of reservations and a specialized
> > deserializer allocator, and instead makes the deserializer allocate
> > directly with the Heap's Allocate method.
> >
> > The major consequence of this is that the GC can now run during
> > deserialization, which means that:
> >
> >   a) Deserialized objects are visible to the GC, and
> >   b) Objects that the deserializer/deserialized objects point to can
> >      move.
> >
> > Point a) is mostly not a problem due to previous work in making
> > deserialized objects "GC valid", i.e. making sure that they have a valid
> > size before any subsequent allocation/safepoint. We now additionally
> > have to initialize the allocated space with a valid tagged value -- this
> > is a magic Smi value to keep "uninitialized" checks simple.
> >
> > Point b) is solved by Handlifying the deserializer. This involves
> > changing any vectors of objects into vectors of Handles, and any object
> > keyed map into an IdentityMap (we can't use Handles as keys because
> > the object's address is no longer a stable hash).
> >
> > Back-references can no longer be direct chunk offsets, so instead the
> > deserializer stores a Handle to each deserialized object, and the
> > backreference is an index into this handle array. This encoding could
> > be optimized in the future with e.g. a second pass over the serialized
> > array which emits a different bytecode for objects that are and aren't
> > back-referenced.
> >
> > Additionally, the slot-walk over objects to initialize them can no
> > longer use absolute slot offsets, as again an object may move and its
> > slot address would become invalid. Now, slots are walked as relative
> > offsets to a Handle to the object, or as absolute slots for the case of
> > root pointers. A concept of "slot accessor" is introduced to share the
> > code between these two modes, and writing the slot (including write
> > barriers) is abstracted into this accessor.
> >
> > Finally, the Code body walk is modified to deserialize all objects
> > referred to by RelocInfos before doing the RelocInfo walk itself. This
> > is because RelocInfoIterator uses raw pointers, so we cannot allocate
> > during a RelocInfo walk.
> >
> > As a drive-by, the VariableRawData bytecode is tweaked to use tagged
> > size rather than byte size -- the size is expected to be tagged-aligned
> > anyway, so now we get an extra few bits in the size encoding.
> >
> > Bug: chromium:1075999
> > Change-Id: I672c42f553f2669888cc5e35d692c1b8ece1845e
> > Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2404451
> > Commit-Queue: Leszek Swirski <leszeks@chromium.org>
> > Reviewed-by: Jakob Gruber <jgruber@chromium.org>
> > Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#70229}
>
> Bug: chromium:1075999
> Change-Id: Ibc77cc48b3440b4a28b09746cfc47e50c340ce54
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2440828
> Commit-Queue: Leszek Swirski <leszeks@chromium.org>
> Auto-Submit: Leszek Swirski <leszeks@chromium.org>
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Reviewed-by: Jakob Gruber <jgruber@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#70267}

TBR=ulan@chromium.org,jgruber@chromium.org,leszeks@chromium.org

Change-Id: Ieed68332ef6a7ad36db061e3f48be0f28673d7a2
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: chromium:1075999
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2441608Reviewed-by: 's avatarZhi An Ng <zhin@chromium.org>
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#70268}
      c7c0e790
    • Leszek Swirski's avatar
      Reland "[serializer] Allocate during deserialization" · 28a30c57
      Leszek Swirski authored 
      This is a reland of 5d7a29c9

This reland shuffles around the order of checks in Heap::AllocateRawWith
to not check the new space addresses until it's known that this is a new
space allocation. This fixes an UBSan failure during read-only space
deserialization, which happens before the new space is initialized.

It also fixes some issues discovered by --stress-snapshot, around
serializing ThinStrings (which are now elided as part of serialization),
handle counts (I bumped the maximum handle count in that check), and
clearing map transitions (the map backpointer field needed a Smi
uninitialized value check).

Original change's description:
> [serializer] Allocate during deserialization
>
> This patch removes the concept of reservations and a specialized
> deserializer allocator, and instead makes the deserializer allocate
> directly with the Heap's Allocate method.
>
> The major consequence of this is that the GC can now run during
> deserialization, which means that:
>
>   a) Deserialized objects are visible to the GC, and
>   b) Objects that the deserializer/deserialized objects point to can
>      move.
>
> Point a) is mostly not a problem due to previous work in making
> deserialized objects "GC valid", i.e. making sure that they have a valid
> size before any subsequent allocation/safepoint. We now additionally
> have to initialize the allocated space with a valid tagged value -- this
> is a magic Smi value to keep "uninitialized" checks simple.
>
> Point b) is solved by Handlifying the deserializer. This involves
> changing any vectors of objects into vectors of Handles, and any object
> keyed map into an IdentityMap (we can't use Handles as keys because
> the object's address is no longer a stable hash).
>
> Back-references can no longer be direct chunk offsets, so instead the
> deserializer stores a Handle to each deserialized object, and the
> backreference is an index into this handle array. This encoding could
> be optimized in the future with e.g. a second pass over the serialized
> array which emits a different bytecode for objects that are and aren't
> back-referenced.
>
> Additionally, the slot-walk over objects to initialize them can no
> longer use absolute slot offsets, as again an object may move and its
> slot address would become invalid. Now, slots are walked as relative
> offsets to a Handle to the object, or as absolute slots for the case of
> root pointers. A concept of "slot accessor" is introduced to share the
> code between these two modes, and writing the slot (including write
> barriers) is abstracted into this accessor.
>
> Finally, the Code body walk is modified to deserialize all objects
> referred to by RelocInfos before doing the RelocInfo walk itself. This
> is because RelocInfoIterator uses raw pointers, so we cannot allocate
> during a RelocInfo walk.
>
> As a drive-by, the VariableRawData bytecode is tweaked to use tagged
> size rather than byte size -- the size is expected to be tagged-aligned
> anyway, so now we get an extra few bits in the size encoding.
>
> Bug: chromium:1075999
> Change-Id: I672c42f553f2669888cc5e35d692c1b8ece1845e
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2404451
> Commit-Queue: Leszek Swirski <leszeks@chromium.org>
> Reviewed-by: Jakob Gruber <jgruber@chromium.org>
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#70229}

Bug: chromium:1075999
Change-Id: Ibc77cc48b3440b4a28b09746cfc47e50c340ce54
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2440828
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Auto-Submit: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: 's avatarUlan Degenbaev <ulan@chromium.org>
Reviewed-by: 's avatarJakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#70267}
      28a30c57
  29. 23 Sep, 2020 1 commit
    • Leszek Swirski's avatar
      [handles] Add a PatchValue method for Handle · ba088da2
      Leszek Swirski authored 
      We currently have a pattern of setting a dereferenced Handle location to
update that Handle's value:

  *handle.location() = new_value.ptr()

This is slightly opaque, and definitely not type-safe, so add a new
Handle<T>::PatchValue method which does this operation.

Ideally we would make Handle::location() return a const pointer to
discourage this sort of use, but there's a bunch of places where that
location pointer is used and passed around as a Handle surrogate, so
those would have to be updated first.

Change-Id: I157f7e2473ed1b86f7a93cae260b0932fed0ad88
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2424249
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: 's avatarIgor Sheludko <ishell@chromium.org>
Reviewed-by: 's avatarJakob Gruber <jgruber@chromium.org>
Auto-Submit: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#70088}
      ba088da2
  31. 14 Aug, 2020 1 commit
    • Leszek Swirski's avatar
      [offthread] Change OffThreadIsolate to LocalIsolate · f1589bbe
      Leszek Swirski authored 
      This patch introduces a new LocalIsolate and LocalFactory, which use
LocalHeap and replace OffThreadIsolate and OffThreadFactory. This allows
us to remove those classes, as well as the related OffThreadSpace,
OffThreadLargeObjectSpace, OffThreadHeap, and OffThreadTransferHandle.
OffThreadLogger becomes LocalLogger.

LocalHeap behaves more like Heap than OffThreadHeap did, so this allows
us to additionally remove the concept of "Finish" and "Publish" that the
OffThreadIsolate had, and allows us to internalize strings directly with
the newly-concurrent string table (where the implementation can now move
to FactoryBase).

This patch also removes the off-thread support from the deserializer
entirely, as well as removing the LocalIsolateWrapper which allowed
run-time distinction between Isolate and OffThreadIsolate. LocalHeap
doesn't support the reservation model used by the deserializer, and we
will likely move the deserializer to use LocalIsolate unconditionally
once we figure out the details of how to do this.

Bug: chromium:1011762

Change-Id: I1a1a0a72952b19a8a4c167c11a863c153a1252fc
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2315990
Commit-Queue: Andreas Haas <ahaas@chromium.org>
Auto-Submit: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: 's avatarAndreas Haas <ahaas@chromium.org>
Reviewed-by: 's avatarUlan Degenbaev <ulan@chromium.org>
Reviewed-by: 's avatarJakob Gruber <jgruber@chromium.org>
Reviewed-by: 's avatarDominik Inführ <dinfuehr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#69397}
      f1589bbe
  33. 12 Aug, 2020 1 commit
    • Santiago Aboy Solanes's avatar
      [compiler] Have one unique PersistentHandles container · 64828a54
      Santiago Aboy Solanes authored 
      The (now unique)PersistentHandles container follows this path:
  1) PersistentHandles created via PersistentHandlesScope inside of
     CompilationHandleScope
  2) Owned by OptimizedCompilationInfo
  3) Owned by JSHeapBroker
  4) Owned by the broker's LocalHeap
  5) Back to the broker for a brief moment (after tearing down the
    LocalHeap as part of exiting LocalHeapScope)
  6) Back to OptimizedCompilationInfo when exiting the LocalHeapScope.

There is a special case in GenerateCodeForTesting where the JSHeapBroker
will not be retired in that same method. In this case, we need to
re-attach the PersistentHandles container to the JSHeapBroker.

The identity map of the persistent & canonical handles also gets passed
around like the persistent handles. The only difference is that is
created in the CanonicalHandleScope (i.e step 1) is different).

Bug: v8:7790
Change-Id: I2da77a7e08f3fd360a46b606c5fbda08c0af27df
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2332811
Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
Reviewed-by: 's avatarGeorg Neis <neis@chromium.org>
Reviewed-by: 's avatarDominik Inführ <dinfuehr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#69360}
      64828a54
  35. 06 Aug, 2020 1 commit
  37. 29 Jul, 2020 1 commit
  39. 28 May, 2020 1 commit
  41. 14 May, 2020 1 commit
    • Leszek Swirski's avatar
      [offthread] Add off thread deserialization · 595609fb
      Leszek Swirski authored 
      Add a new OffThreadObjectDeserializer, which can deserialize a snapshot
into an OffThreadIsolate.

This involves templating the Deserializer base class on Isolate, and
amending OffThreadHeap to be able to create Reservations same as the
main-thread Heap can. Various off-thread incompatible methods are
stubbed out as UNREACHABLE in OffThreadIsolate overloads.

There is currently no API entry into the off-thread deserialization, but
under --stress-background-compile it now runs the CodeDeserializer (i.e.
code cache deserialization) in a background thread.

Bug: chromium:1075999

Change-Id: I2453f51ae31df4d4b6aa94b0804a9d6d3a03781e
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2172741
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: 's avatarJakob Gruber <jgruber@chromium.org>
Reviewed-by: 's avatarIgor Sheludko <ishell@chromium.org>
Reviewed-by: 's avatarUlan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67799}
      595609fb
  43. 15 Apr, 2020 1 commit
  45. 25 Mar, 2020 1 commit
  47. 04 Mar, 2020 1 commit
  49. 02 Mar, 2020 1 commit
  51. 20 Feb, 2020 1 commit
  53. 13 Feb, 2020 1 commit
  55. 12 Feb, 2020 2 commits
  57. 06 Feb, 2020 2 commits
  59. 04 Feb, 2020 1 commit
    • Leszek Swirski's avatar
      [offthread] Add an OffThreadIsolate · 7a20b6b9
      Leszek Swirski authored 
      The Factory/OffThreadFactory allows us to cleanly separate object
construction behaviour between main-thread and off-thread in a
syntactically consistent way (so that methods templated on the factory
type can be made to work on both).

However, there are cases where we also have to access the Isolate, for
handle creation or exception throwing. So far we have been pushing more
and more "customization points" into the factories to allow these
factory-templated methods to dispatch on this isolate behaviour via
these factory methods. Unfortunately, this is an increasing layering
violation between Factory and Isolate, particularly around exception
handling.

Now, we introduce an OffThreadIsolate, analogous to Isolate in the same
way as OffThreadFactory is analogous to Factory. All methods which were
templated on Factory are now templated on Isolate, and methods which
used to take an Isolate, and which were recently changed to take a
templated Factory, are changed/reverted to take a templated Isolate.
OffThreadFactory gets an isolate() method to match Factory's.

Notably, FactoryHandle is changed to "HandleFor", where the template
argument can be either of the Isolate type or the Factory type (allowing
us to dispatch on both depending on what is available).

Bug: chromium:1011762
Change-Id: Id144176f7da534dd76f3d535ab2ade008b6845e3
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2030909
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: 's avatarToon Verwaest <verwaest@chromium.org>
Reviewed-by: 's avatarUlan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#66101}
      7a20b6b9
  61. 16 Jan, 2020 1 commit
    • Leszek Swirski's avatar
      [offthread] Add OffThreadFactory support to AST strings · bcbb553d
      Leszek Swirski authored 
      Add support for internalizing an AstValueFactory using the off-thread
factory. Includes adding ConsString support to OffThreadFactory.

This introduces a Handle union wrapper, which is used in locations that
can store a Handle or an OffThreadHandle. This is used in this patch for
the internalized "string" field of AST strings, and will be able to be
used for other similar fields in other classes (e.g. the ScopeInfo
handle in Scope, object boilerplate descriptor handles, the inferred
name handle on FunctionLiterals, etc.). It has a Factory-templated
getter which returns the appropriate handle for the factory, and a
debug-only tag to make sure the right getter is used at runtime. This
union wrapper currently decomposes implicitly to a Handle if the getter
is not called, to minimise code changes, but this implicit conversion
will likely be removed for clarity.

Bug: chromium:1011762
Change-Id: I5dd3a7bbdc483b66f5ff687e0079c545b636dc13
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1993971
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: 's avatarUlan Degenbaev <ulan@chromium.org>
Reviewed-by: 's avatarToon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#65816}
      bcbb553d
  63. 15 Jan, 2020 1 commit
    • Leszek Swirski's avatar
      [offthread] Add OffThreadFactory · e659917a
      Leszek Swirski authored 
      Introduce OffThreadFactory with initial string construction support.

The OffThreadFactory shares with Factory a new CRTP base class, called
FactoryBase. Methods in FactoryBase return a FactoryHandle<Factory, T>
alias, which is Handle<T> for normal Factory and a new OffThreadHandle<T>
for OffThreadFactory. OffThreadHandle<T> behaves like Handle<T>, except
it stores the object in-line rather than needing external storage.

Any shared factory methods are moved into FactoryBase, which uses CRTP
to call the sub-class's AllocateRaw method (plus a few more customization
points which need Isolate access on the main thread).

Methods that used to take an Isolate or Factory, and are needed off the
main thread, are now expected to be templated on the factory type and
to use the appropriate handle.

Once an OffThreadFactory has finished being used (e.g. off-thread
compilation completed) its pages are "Published" into the main-thread
Heap. To deal with string internalization without creating a bunch of
ThinStrings, this is done in two stages:

  1. 'FinishOffThread': The off-thread pages are walked to
     collect all slots pointing to "internalized" strings. After this is
     called it is invalid to allocate any more objects with the factory.
  2. 'Publish': On the main thread, we transform these slots into
     <Handle to holder, offset> pairs, then for each saved slot
     re-internalize its string and update the slot to point to the
     internalized string.

Bug: chromium:1011762
Change-Id: I008a694da3c357de34362bd86fe7e1f46b535d5e
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1992434
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: 's avatarUlan Degenbaev <ulan@chromium.org>
Reviewed-by: 's avatarToon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#65787}
      e659917a
  65. 17 Sep, 2019 1 commit
  67. 24 May, 2019 1 commit