This relands commit e71b802279.
This can now back in as the fix for chromium:787301 had enough time to
be tested in Canary.
Original change's description:
> [deoptimizer] Staged materialization of objects.
>
> The existing object materialization in the deoptimizer has the following problems:
>
> - Objects do not necessarily verify during materialization (because during the
> depth first walk we might have inconsistent objects).
>
> - Stack can overflow (because we just materialize using recursive calls).
>
> - We generalize object fields.
>
>
> This CL re-implements the materialization algorithm to solve this problem. The
> new implementation creates the objects in two steps:
>
> 1. We allocate space for all the objects. In general, we allocate ByteArrays
> of the right size. For leaf objects that cannot participate in cycles,
> we build and initialize the materialized objects completely.
>
> For JS objects, we insert markers into the byte array at the positions
> where unboxed doubles are expected.
>
> 2. We initialize all the objects with the proper field values and change the
> map from the ByteArray map to the correct map. This requires some sync
> with the concurrent marker (Heap::NotifyObjectLayoutChange).
>
> When initializing the JS object fields, we make sure that we respect
> the unboxed double marker.
>
> Bug: chromium:770106, v8:3836
> Change-Id: I1ec466a9d19db9538df4ba915516d4c3ca825632
> Reviewed-on: https://chromium-review.googlesource.com/777559
> Commit-Queue: Jaroslav Sevcik <jarin@chromium.org>
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#49821}
Bug: chromium:770106, v8:3836
Change-Id: Ied6c4e0fbae52713e55ae6dc13794a7521dbb8a5
Reviewed-on: https://chromium-review.googlesource.com/817745
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49982}
This reverts commit e71b802279.
Reason for revert: Need to have a back-mergeable fix.
Original change's description:
> [deoptimizer] Staged materialization of objects.
>
> The existing object materialization in the deoptimizer has the following problems:
>
> - Objects do not necessarily verify during materialization (because during the
> depth first walk we might have inconsistent objects).
>
> - Stack can overflow (because we just materialize using recursive calls).
>
> - We generalize object fields.
>
>
> This CL re-implements the materialization algorithm to solve this problem. The
> new implementation creates the objects in two steps:
>
> 1. We allocate space for all the objects. In general, we allocate ByteArrays
> of the right size. For leaf objects that cannot participate in cycles,
> we build and initialize the materialized objects completely.
>
> For JS objects, we insert markers into the byte array at the positions
> where unboxed doubles are expected.
>
> 2. We initialize all the objects with the proper field values and change the
> map from the ByteArray map to the correct map. This requires some sync
> with the concurrent marker (Heap::NotifyObjectLayoutChange).
>
> When initializing the JS object fields, we make sure that we respect
> the unboxed double marker.
>
> Bug: chromium:770106, v8:3836
> Change-Id: I1ec466a9d19db9538df4ba915516d4c3ca825632
> Reviewed-on: https://chromium-review.googlesource.com/777559
> Commit-Queue: Jaroslav Sevcik <jarin@chromium.org>
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#49821}
TBR=ulan@chromium.org,mstarzinger@chromium.org,jarin@chromium.org
Change-Id: I0657fb75330700dd7883c600dacb25676ebb47f9
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: chromium:770106, v8:3836
Reviewed-on: https://chromium-review.googlesource.com/806160
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Jaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49834}
The existing object materialization in the deoptimizer has the following problems:
- Objects do not necessarily verify during materialization (because during the
depth first walk we might have inconsistent objects).
- Stack can overflow (because we just materialize using recursive calls).
- We generalize object fields.
This CL re-implements the materialization algorithm to solve this problem. The
new implementation creates the objects in two steps:
1. We allocate space for all the objects. In general, we allocate ByteArrays
of the right size. For leaf objects that cannot participate in cycles,
we build and initialize the materialized objects completely.
For JS objects, we insert markers into the byte array at the positions
where unboxed doubles are expected.
2. We initialize all the objects with the proper field values and change the
map from the ByteArray map to the correct map. This requires some sync
with the concurrent marker (Heap::NotifyObjectLayoutChange).
When initializing the JS object fields, we make sure that we respect
the unboxed double marker.
Bug: chromium:770106, v8:3836
Change-Id: I1ec466a9d19db9538df4ba915516d4c3ca825632
Reviewed-on: https://chromium-review.googlesource.com/777559
Commit-Queue: Jaroslav Sevcik <jarin@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49821}
