• Jakob Gruber's avatar
    Reland "[compiler] Consider IsPendingAllocation in Ref construction" · 4683d6fe
    Jakob Gruber authored
    This is a reland of 5f0ac36c
    
    Fixes Ref construction failures in:
    - MapRef::instance_descriptors
    - NativeContext reads (see also crrev.com/c/2891575)
    
    Original change's description:
    > [compiler] Consider IsPendingAllocation in Ref construction
    >
    > The logic in JSHeapBroker::TryGetOrCreateData assumes that parts
    > of the object are safe to read. In particular, the instance type
    > must be readable for the chain of `Is##Name()` type checks.
    >
    > This is guaranteed if
    >
    >  - a global memory fence happened after object initialization and
    >    prior to the read by the compiler; or
    >  - the object was published through a release store and read through
    >    an acquire read.
    >
    > The former is protected by the new call to ObjectMayBeUninitialized
    > (which internally calls IsPendingAllocation) in TryGetOrCreateData.
    >
    > The latter must be marked explicitly by calling the new
    > MakeRefAssumeMemoryFence variant.
    >
    > Note that support in this CL is expected to be incomplete and will
    > have to be extended in the future as more cases show up in which
    > MakeRef calls must be converted to MakeRefAssumeMemoryFence or to
    > TryMakeRef.
    >
    > Bug: v8:7790,v8:11711
    > Change-Id: Ic2f7d9fc46e4bfc3f6bbe42816f73fc5ec174337
    > Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2874663
    > Commit-Queue: Jakob Gruber <jgruber@chromium.org>
    > Reviewed-by: Georg Neis <neis@chromium.org>
    > Cr-Commit-Position: refs/heads/master@{#74474}
    
    Bug: v8:7790,v8:11711,chromium:1207680,chromium:1207679
    Change-Id: Ib3dbf59909e6982a3230dd6a67c9fb7d6ffb9ab4
    Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2886861Reviewed-by: 's avatarGeorg Neis <neis@chromium.org>
    Commit-Queue: Jakob Gruber <jgruber@chromium.org>
    Cr-Commit-Position: refs/heads/master@{#74587}
    4683d6fe
Name
Last commit
Last update
..
benchmarks Loading commit data...
cctest Loading commit data...
common Loading commit data...
debugger Loading commit data...
debugging Loading commit data...
fuzzer Loading commit data...
fuzzilli Loading commit data...
inspector Loading commit data...
intl Loading commit data...
js-perf-test Loading commit data...
memory Loading commit data...
message Loading commit data...
mjsunit Loading commit data...
mkgrokdump Loading commit data...
mozilla Loading commit data...
test262 Loading commit data...
torque Loading commit data...
unittests Loading commit data...
wasm-api-tests Loading commit data...
wasm-js Loading commit data...
wasm-spec-tests Loading commit data...
webkit Loading commit data...
BUILD.gn Loading commit data...
OWNERS Loading commit data...