This test tests the interpreted/baseline and optimized behaviour of cpu
profiler ticks. We should eventually support this for maglev too, but
for now just disable it.

Bug: v8:7700
Change-Id: Iba89ab2c718025ebf90c86a84ed937c2d1d0af7f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3647363
Auto-Submit: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80531}

This is more consistent with similar features, for example
V8_ENABLE_WEBASSEMBLY or V8_ENABLE_MAGLEV.

Drive-by: remove V8_SANDBOX_IS_AVAILABLE as it's no longer needed.

Bug: v8:10391
Change-Id: I8658c5b0c331a4c73892737083b2c2f9b8f84056
Cq-Include-Trybots: luci.v8.try:v8_linux64_heap_sandbox_dbg_ng,v8_linux_arm64_sim_heap_sandbox_dbg_ng
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3647355
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Auto-Submit: Samuel Groß <saelo@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80530}

This introduces a class which can be used for formatting dynamic values
into a constant-size, stack-allocated array. You get ostream-style code
but printf-style performance, and in particular no dynamic allocation.
This makes this class also suitable to be used in OOM or other fatal
situations where we cannot rely on dynamic memory allocation to still
work.

Using FormattedString will automatically compute the format string
depending on the types. It also computes the maximum size of the output.
Last but not least, it makes the code a lot more readable than
traditional printf style printing.

R=mlippautz@chromium.org

Bug: chromium:1323177
Change-Id: I47228b3603c694c1fa23516dd3f1c57e39c0ca35
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3644622
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80529}

We initialize the JSObject in the payload of a ByteArray, so we know
that no slots were recorded there. This also means we don't need to
remove any recorded slots and thus invalidation isn't required.

With this change only strings use object slot invalidation on
String::MakeExternal.

Bug: v8:12578
Change-Id: I009635c2a61ae8ff2b9e2480cb7d374451a8cc7d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3644614Reviewed-by: Nico Hartmann <nicohartmann@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Dominik Inführ <dinfuehr@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80528}

This avoids unnecessary spill moves and reduces register pressure.

Bug: v8:7700
Change-Id: I3f2c35f2b6c0a3e64408b40d59696d924af8a9b4
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3647365Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80527}

Bug: v8:12868
Change-Id: I69e149aa607ee77dd00267a0bbe4e5828dceb75e
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3647350Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Commit-Queue: Andy Wingo <wingo@igalia.com>
Cr-Commit-Position: refs/heads/main@{#80526}

Explicitly initialize the loop merge's back-edge predecessor to a
specfic "uninitialized" value, distinct from nullptr (which marks dead
loops) and done in both debug and release modes.

Bug: v8:7700
Change-Id: I6a845cc4dbd7da75954f78607e69a5d4e2ec1ec7
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3645114Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Auto-Submit: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80525}

Now that we require C++17 support, we can just use the standard
static_assert without message, instead of our STATIC_ASSERT macro.

R=leszeks@chromium.org

Bug: v8:12425
Change-Id: I1d4e39c310b533bcd3a4af33d027827e6c083afe
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3647353Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Hannes Payer <hpayer@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80524}

Bug: v8:12868
Change-Id: I9008da5f89c4c18ea45ddbe44cae832087c76b01
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3647349Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Commit-Queue: Andy Wingo <wingo@igalia.com>
Cr-Commit-Position: refs/heads/main@{#80523}

JobDelegate::ShouldYield() should not be called anymore after it has
already returned true. This CL changes the deserialization of
WebAssembly to remember when ShouldYield() returned for the first time,
and does not call ShouldYield() afterwards anymore.

R=thibaudm@chromium.org

Bug: chromium:1277962
Change-Id: Ie84abf30b20d302a19f3192c3859796be1cccd97
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3647361
Commit-Queue: Andreas Haas <ahaas@chromium.org>
Reviewed-by: Thibaud Michaud <thibaudm@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80522}

With this CL, the decompression simply becomes:
       movsxd  rax, edi
       add     rax, rax
       and     rax, qword ptr fs:[base@TPOFF]

Bug: chromium:1325007

Change-Id: I931e4e667a9b9697671bccf14575420f8cb705e8
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3629871Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Anton Bikineev <bikineev@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80521}

This reverts commit b8f88be0.

Reason: disabling an experimental feature in release branch

Bug: v8:11111,v8:12870
Change-Id: I6fbd6bdb318c0d25e69c04db208a0d5f2b9ebbd7
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3647357
Auto-Submit: Marja Hölttä <marja@chromium.org>
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80520}

Do the same trick as TurboFan, keeping the BytecodeArray alive by
holding it strongly in the deopt literals.

Bug: v8:7700
Change-Id: I8f8472674b08df3ca18aff58172e7ba83d09a620
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3647358
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80519}

With caged heap enabled, we can halve Member<> by storing only the least
significant half. The base of the heap is stored in a thread local
variable. The feature has therefore an implication that only single heap
is allowed per thread.

The feature is gated by the new GN arg:
  cppgc_enable_pointer_compression.

Bug: chromium:1325007

Change-Id: Ic7f1ecb7b9ded57caad63d95bbc8e8ad6ad65031
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2739979Reviewed-by: Almothana Athamneh <almuthanna@chromium.org>
Commit-Queue: Almothana Athamneh <almuthanna@chromium.org>
Commit-Queue: Tamer Tas <tmrts@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Tamer Tas <tmrts@chromium.org>
Auto-Submit: Anton Bikineev <bikineev@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80518}

Use V8::FatalProcessOutOfMemory directly instead.

R=mlippautz@chromium.org

Bug: chromium:1323177
Change-Id: Ib1efd9e8099c76cd9ae0ac412b2e37307a698f4f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3641176Reviewed-by: Patrick Thier <pthier@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Marja Hölttä <marja@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80517}

We temporarily enable the StringForwardingTable for all ThinString
transitions behind --future to get coverage and performance numbers from
future bots.

Bug: v8:12007
Change-Id: Ia59bd6c40df2fd413867f6fc2aa7f69d099b5377
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3637799Reviewed-by: Shu-yu Guo <syg@chromium.org>
Commit-Queue: Patrick Thier <pthier@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80516}

NOTRY=true

Bug: v8:12445
Change-Id: I67bd72e2369ffc0e4afc75e0436d80d3c5c0fae2
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3632101Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Almothana Athamneh <almuthanna@chromium.org>
Auto-Submit: Almothana Athamneh <almuthanna@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80515}

This CL adds serialization and deserialization for
packed double array and holey double array.

Bug: v8:11525
Change-Id: Idce22e1c5d707e45127ae972587c6b7808ca2cda
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3640751Reviewed-by: Marja Hölttä <marja@chromium.org>
Commit-Queue: 王澳 <wangao.james@bytedance.com>
Cr-Commit-Position: refs/heads/main@{#80514}

Spec text:
https://tc39.es/proposal-temporal/#sec-temporal.calendar.prototype.era
https://tc39.es/proposal-temporal/#sec-temporal.calendar.prototype.erayear

Notice this only implement the "iso8601" calendar and we will implement the
code for other calendar later by calling ICU with other Calendar methods.
This CL reduce the differences of testing result between ALWAYS and no_i18n
because the code in no_i18n will not call Calendar era or eraYear and therefore
passed the test even w/o this CL but the ALWAYS tests will cause Temporal
object to internal call era and eraYear and therefore fail if w/o this CL.

Bug: v8:11544
Change-Id: I921fbfbbd26473c238024161eb58b096c38b881b
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3641938Reviewed-by: Adam Klein <adamk@chromium.org>
Commit-Queue: Frank Tang <ftang@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80513}

Doesn't do much at the moment beyond not being a baseline frame. Fixes a
DCHECK in tiering that checks the frame type, by removing the frame
lookup there (which wasn't necessary anymore).

Bug: v8:7700
Change-Id: Icecfe27771923d380a7d1dc1c29aa9c5c9dfbf0f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3644618
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Auto-Submit: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80512}

We use the invalidate_recorded_slots argument to signal to NotifyObjectLayoutChange whether a particular object layout change
could cause a tagged pointer to be replaced with an untagged value.
In such cases we need our snapshot protocol in order to allow marking
such objects concurrently.

The snapshot protocol consists of two main operations:
  1) Tracing and marking the object black on the main thread before
     performing the unsafe transition.
  2) The concurrent marker needs to read such objects into a buffer
     first and is only allowed to trace it when successfully marking
     that object black.

However, in some cases we were still doing 1) on the main thread when
the concurrent marker didn't use 2) the snapshot buffer anymore. This
CL cleans up this behavior and ensures that 1) and 2) are always paired
together.

Bug: v8:12578
Change-Id: Id83b3de866a80efedf4a72e440cbc767fe3eaea6
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3644611Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Dominik Inführ <dinfuehr@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80511}

The budget interrupt in maglev can clobber registers. We need to save
the caller-saved registers before making this call.

Additionally, move the interrupt call into deferred code, and only emit
the interrupt check + call for returns and backwards jumps (i.e. things
that reduce the budget).

Bug: v8:7700
Change-Id: I277e9fdf454ff0f22bf20e7cf9538e3020403c1a
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3644619Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80510}

Port GN changes in https://crrev.com/c/3596671

No-Try: true
Change-Id: I4d9571ce0d5abcae56a370986db1104e5429b348
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3647347Reviewed-by: Andreas Haas <ahaas@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80509}

Change-Id: Iad4b34b1c4a85800e8e1d6c01b686dd19e8116a6
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3600532
Auto-Submit: Yahan Lu <yahan@iscas.ac.cn>
Reviewed-by: ji qiu <qiuji@iscas.ac.cn>
Commit-Queue: ji qiu <qiuji@iscas.ac.cn>
Cr-Commit-Position: refs/heads/main@{#80508}

Port commit fe443a4e

Bug: v8:12284

Change-Id: I19ba180ecc7cd0e5a3b6e5009cc2b8c40074399a
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3642243Reviewed-by: ji qiu <qiuji@iscas.ac.cn>
Auto-Submit: Yahan Lu <yahan@iscas.ac.cn>
Commit-Queue: ji qiu <qiuji@iscas.ac.cn>
Cr-Commit-Position: refs/heads/main@{#80507}

CompilationSubCache has some complexity regarding generations of tables
which is only used by one subclass, CompilationCacheRegExp. This change
adjusts the class hierarchy so that classes only contain the necessary
member functions.

Bug: v8:12808
Change-Id: I4f4cf15bbf9b80c2de0c18aea82a0c238804759d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3629603Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Seth Brenith <seth.brenith@microsoft.com>
Cr-Commit-Position: refs/heads/main@{#80506}

This CL adds two experimental JS builtins to convert between
i16 Wasm GC and JS strings. This is a non-standard experimental
feature only available with the flag --wasm-gc-js-interop.

WebAssembly.experimentalConvertArrayToString(array, start, count)
Convert the `count`-many WTF-16 code units starting at index `start`
into a JS string. Throws a TypeError if `array` is not an i16 array,
or if `start` and `count` are not numbers or not in range.

WebAssembly.experimentalConvertStringToArray(string, sampleArray)
Convert `string` to an i16 array. The `sampleArray` parameter needs
to be an arbitrary i16 array, which is only used to extract the rtt.
Throws a TypeError if `string` is not a string or `sampleArray` is not
an i16 array.

Change-Id: I7ac2f6bd89b8f638427f61da1bb01ccba90d735b
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3642301
Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80505}

Bug: v8:12284
Change-Id: Ica2564e8b34f8edd9492ef379cf3a3eb5575633d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3642948
Commit-Queue: Deepti Gandluri <gdeepti@chromium.org>
Reviewed-by: Thibaud Michaud <thibaudm@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80504}

Bug: v8:12612
Change-Id: Ib24496c1a3789ced50431818874e27886e92a909
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3644616Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Omer Katz <omerkatz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80503}

Bug: v8:12284
Change-Id: I7f6a4a5182ad61dfdc13faf2ced99fba7d64c9c5
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3640926Reviewed-by: Thibaud Michaud <thibaudm@chromium.org>
Commit-Queue: Deepti Gandluri <gdeepti@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80502}

Change-Id: Id6c520cd3cc6218fb32fea2c82b0ff8985e2b58e
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3627012
Commit-Queue: Anton Bikineev <bikineev@chromium.org>
Auto-Submit: Chong Gu <chonggu@google.com>
Reviewed-by: Anton Bikineev <bikineev@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80501}

Fixed: v8:12866
Change-Id: Icba2ffc7837bf4942fd4bc741abeb7c98694c2d8
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3644607Reviewed-by: Manos Koukoutos <manoskouk@chromium.org>
Auto-Submit: Jakob Kummerow <jkummerow@chromium.org>
Reviewed-by: Andy Wingo <wingo@igalia.com>
Commit-Queue: Manos Koukoutos <manoskouk@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80500}

Change-Id: I933301cf9b81ef6a5cc5ec891611464a1e0a1e48
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3645029
Commit-Queue: Junliang Yan <junyan@redhat.com>
Reviewed-by: Milad Farazmand <mfarazma@redhat.com>
Cr-Commit-Position: refs/heads/main@{#80499}

Bug: v8:12612
Change-Id: I47bf134a9ff57a5c4ace9d35bf023a1c5e248896
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3644615Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Omer Katz <omerkatz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80498}

Bug: v8:12284
Change-Id: I9d8f9da8ed736d5119e7af4354e1ddd8a255713d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3640925
Commit-Queue: Deepti Gandluri <gdeepti@chromium.org>
Reviewed-by: Thibaud Michaud <thibaudm@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80497}

This reverts commit 411a0157.

Reason for revert: crbug.com/1324829 (Canary crashes)

Original change's description:
> Reland "[rwx][mac] Enable fast W^X on Apple Silicon (M1)"
>
> This is a reland of commit e8cac377
> Broken jitless mode is fixed in a separate CL.
>
> Original change's description:
> > [rwx][mac] Enable fast W^X on Apple Silicon (M1)
> >
> > Bug: v8:12797
> > Change-Id: I53bb803dd77db5bdd42b1a1b4b568e63857adf31
> > Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3598861
> > Reviewed-by: Toon Verwaest <verwaest@chromium.org>
> > Commit-Queue: Igor Sheludko <ishell@chromium.org>
> > Cr-Commit-Position: refs/heads/main@{#80396}
>
> Bug: v8:12797
> Change-Id: I5436ceced5d4673f3b80d9cacdb3d6e84012c6e7
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3635720
> Reviewed-by: Toon Verwaest <verwaest@chromium.org>
> Commit-Queue: Igor Sheludko <ishell@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#80450}

Bug: v8:12797
Change-Id: If776ccb6ce9f41a84b94409ec5cae91c0915f129
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3644620
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Cr-Commit-Position: refs/heads/main@{#80496}

This reverts commit 8278cb50.

Reason for revert: breaking https://ci.chromium.org/ui/p/v8/builders/ci/V8%20Linux%20-%20arm64%20-%20sim%20-%20CFI/10778/overview

Original change's description:
> [inspector] Re-enable Debugger#restartFrame
>
> Doc: https://bit.ly/revive-restart-frame
>
> This CL "undeprecates" Debugger#restartFrame and adds a new optional
> "mode" parameter for back-wards compatibility. Moreover, the return
> values are all deprecated. They were never actually used in the
> DevTools frontend and the same information is available from the
> Debugger#paused event that fires once execution stops at the
> beginning of the restarted function.
>
> The CL also re-baselines all the restart-frame inspector tests that
> now run successfully.
>
> R=​bmeurer@chromium.org, kimanh@chromium.org
>
> Bug: chromium:1303521
> Change-Id: I34bddeb1f2f4ff3dee58dd82e779c111495566f3
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3616505
> Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
> Reviewed-by: Kim-Anh Tran <kimanh@chromium.org>
> Commit-Queue: Simon Zünd <szuend@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#80491}

Bug: chromium:1303521
Change-Id: Ibc33328c31a4b6ea736d07ce5e5ee109039eec8b
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3645767
Commit-Queue: Deepti Gandluri <gdeepti@chromium.org>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Owners-Override: Deepti Gandluri <gdeepti@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80495}

The IsValidSectionCode function shouldn't include internally-used
numeric identifiers of well-known optional sections.

Fixed: v8:12867
Change-Id: I9d894ee57157455e92a17ddcde94f32f05fb038d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3644612
Auto-Submit: Jakob Kummerow <jkummerow@chromium.org>
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80494}

This reverts commit c3ac338b.

Reason for revert: Breaks stepping with `n`

Original change's description:
> [tools] Add a simple gdb frame unwinder
>
> Add a simple unwinder for gdb which, on x64,  walks frame pointers
> whenever there is no source information available. Ideally we would only
> do this for V8 PCs but this appears hard to do in an Unwinder without
> messing with gdb's internal assumptions.
>
> Change-Id: Iba1e62a3768340ee912e81d691237c1920a8ae91
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3608628
> Reviewed-by: Camillo Bruni <cbruni@chromium.org>
> Commit-Queue: Leszek Swirski <leszeks@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#80204}

Change-Id: I0264cf34cfe8fe2331bacf202dedbb4706535936
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3644855
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Auto-Submit: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80493}

This CL separates logic for promoting all of new space during fast
promotion out of the heap and into a new dedicated
PromoteYoungGenerationGC class.

It currently assumes SemiSpaceNewSpace and will need to be extended with
support for PagedNewSpace.

Bug: v8:12612
Change-Id: I0e65c034b444634a31b3c00df0a4b558612f023f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3644610Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Omer Katz <omerkatz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80492}