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  1. 29 Apr, 2022 6 commits
  3. 28 Apr, 2022 29 commits
  5. 27 Apr, 2022 5 commits
    • Frank Tang's avatar
      [Temporal] Add PlainDateTime.from · f09026a6
      Frank Tang authored 
      Also add AOs: ToTemporalDateTime, ParseTemporalDateTimeString,
InterpretTemporalDateTimeFields

Spec Text:
https://tc39.es/proposal-temporal/#sec-temporal.plaindatetime.from
https://tc39.es/proposal-temporal/#sec-temporal-totemporaldatetime
https://tc39.es/proposal-temporal/#sec-temporal-parsetemporaldatetimestring
https://tc39.es/proposal-temporal/#sec-temporal-interprettemporaldatetimefields

Bug: v8:11544
Change-Id: I3cf5c7c0f876dd8f384d62a47d7b24d8780bf03f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3538667Reviewed-by: 's avatarAdam Klein <adamk@chromium.org>
Commit-Queue: Frank Tang <ftang@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80240}
      f09026a6
    • Adam Klein's avatar
      Revert "[rwx][mac] Support fast W^X permission switching on Apple Silicon (M1)" · 10807c9f
      Adam Klein authored 
      This reverts commit 9d31f866.

Reason for revert: crashes on Mac/arm64 bots:
https://ci.chromium.org/ui/p/v8/builders/ci/V8%20Mac%20-%20arm64%20-%20debug/5923/overview

Original change's description:
> [rwx][mac] Support fast W^X permission switching on Apple Silicon (M1)
>
> ... for V8 code space. The feature is currently disabled.
>
> In order to use fast W^X permission switching we must allocate
> executable pages with readable writable executable permissions (RWX).
> However, MacOS on ARM64 ("Apple M1"/Apple Silicon) prohibits further
> permission changing of RWX memory pages. This means that the code page
> headers must be allocated with RWX permissions too because otherwise
> it wouldn't be possible to allocate a large code page over the freed
> regular code page and vice versa.
>
> When enabled, the new machinery works as follows:
>
> 1) when memory region is reserved for allocating executable pages, the
>    whole region is committed with RWX permissions and then decommitted,
> 2) since reconfiguration of RWX page permissions is not allowed on
>    MacOS on ARM64 ("Apple M1"/Apple Silicon), there must be no attempts
>    to change them,
> 3) the request to set RWX permissions in the executable page region
>    just recommits the pages without changing permissions (see (1), they
>    were already allocated as RWX and then discarded),
> 4) in order to make executable pages inaccessible one must use
>    OS::DiscardSystemPages() instead of OS::DecommitPages() or
>    setting permissions to kNoAccess because the latter two are not
>    allowed by the MacOS (see (2)).
> 5) since code space page headers are allocated as RWX pages it's also
>    necessary to switch between W^X modes when updating the data in the
>    page headers (i.e. when marking, updating stats, wiring pages in
>    lists, etc.). The new CodePageHeaderModificationScope class is used
>    in the respective places. On unrelated configurations it's a no-op.
>
> The fast permission switching can't be used for V8 configuration with
> enabled pointer compression and disabled external code space because
> a) the pointer compression cage has to be reserved with MAP_JIT flag
>    which is too expensive,
> b) in case of shared pointer compression cage if the code range will
>    be deleted while the cage is still alive then attempt to configure
>    permissions of pages that were previously set to RWX will fail.
>
> This also CL extends the unmapper unit tests with permissions tracking
> for discarded pages.
>
> Bug: v8:12797
> Change-Id: Idb28cbc481306477589eee9962d2e75167d87c61
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3579303
> Reviewed-by: Nico Hartmann <nicohartmann@chromium.org>
> Reviewed-by: Clemens Backes <clemensb@chromium.org>
> Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
> Commit-Queue: Igor Sheludko <ishell@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#80238}

Bug: v8:12797
Change-Id: Ic07948e036db36326d464a2a901d052aa060a406
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3611665
Commit-Queue: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Auto-Submit: Adam Klein <adamk@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80239}
      10807c9f
    • Igor Sheludko's avatar
      [rwx][mac] Support fast W^X permission switching on Apple Silicon (M1) · 9d31f866
      Igor Sheludko authored 
      ... for V8 code space. The feature is currently disabled.

In order to use fast W^X permission switching we must allocate
executable pages with readable writable executable permissions (RWX).
However, MacOS on ARM64 ("Apple M1"/Apple Silicon) prohibits further
permission changing of RWX memory pages. This means that the code page
headers must be allocated with RWX permissions too because otherwise
it wouldn't be possible to allocate a large code page over the freed
regular code page and vice versa.

When enabled, the new machinery works as follows:

1) when memory region is reserved for allocating executable pages, the
   whole region is committed with RWX permissions and then decommitted,
2) since reconfiguration of RWX page permissions is not allowed on
   MacOS on ARM64 ("Apple M1"/Apple Silicon), there must be no attempts
   to change them,
3) the request to set RWX permissions in the executable page region
   just recommits the pages without changing permissions (see (1), they
   were already allocated as RWX and then discarded),
4) in order to make executable pages inaccessible one must use
   OS::DiscardSystemPages() instead of OS::DecommitPages() or
   setting permissions to kNoAccess because the latter two are not
   allowed by the MacOS (see (2)).
5) since code space page headers are allocated as RWX pages it's also
   necessary to switch between W^X modes when updating the data in the
   page headers (i.e. when marking, updating stats, wiring pages in
   lists, etc.). The new CodePageHeaderModificationScope class is used
   in the respective places. On unrelated configurations it's a no-op.

The fast permission switching can't be used for V8 configuration with
enabled pointer compression and disabled external code space because
a) the pointer compression cage has to be reserved with MAP_JIT flag
   which is too expensive,
b) in case of shared pointer compression cage if the code range will
   be deleted while the cage is still alive then attempt to configure
   permissions of pages that were previously set to RWX will fail.

This also CL extends the unmapper unit tests with permissions tracking
for discarded pages.

Bug: v8:12797
Change-Id: Idb28cbc481306477589eee9962d2e75167d87c61
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3579303Reviewed-by: 's avatarNico Hartmann <nicohartmann@chromium.org>
Reviewed-by: 's avatarClemens Backes <clemensb@chromium.org>
Reviewed-by: 's avatarMichael Lippautz <mlippautz@chromium.org>
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80238}
      9d31f866
    • Camillo Bruni's avatar
      [runtime] DHECK that builtins correctly return the exception object · 1332c740
      Camillo Bruni authored 
      Runtime and Builtin function should always return the exception object
as a marker if there is a pending_exception on the current isolate.

Change-Id: I7c255aa501800384c288664a9ca6578afbe0a103
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3610449Reviewed-by: 's avatarVictor Gomes <victorgomes@chromium.org>
Commit-Queue: Camillo Bruni <cbruni@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80237}
      1332c740
    • Camillo Bruni's avatar
      [counters] Remove unused counters from V8 · e5c1ada3
      Camillo Bruni authored 
      Change-Id: Iec93e286c8067453cc1f9a978fa09b8734999f83
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3596159Reviewed-by: 's avatarDominik Inführ <dinfuehr@chromium.org>
Commit-Queue: Camillo Bruni <cbruni@chromium.org>
Reviewed-by: 's avatarJakob Linke <jgruber@chromium.org>
Reviewed-by: 's avatarMarja Hölttä <marja@chromium.org>
Reviewed-by: 's avatarIgor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80236}
      e5c1ada3