On Linux, both APIs uses {madvise} (and {SetPermissions} additionally
does an {mprotect}), on windows they use different APIs. It turns out that
{SetPermissions} with {kNoAccess} uses {VirtualFree} with
{MEM_DECOMMIT}, so the pages will only be "reserved" afterwards.
{DiscardSystemPages} on the other hand uses the {DiscardVirtualMemory}
which tells the OS that the content of that memory can be discarded,
but the pages stay "committed".
Thus {SetPermissions} with {kNoAccess} frees significantly more memory
than using {DiscardSystemPages}.

R=mstarzinger@chromium.org

Bug: v8:8217
Change-Id: I3555462a9c692f15ecb3eca7834eb181617d9ef9
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1730992Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63029}

This CL adds new ProcessedFeedback subclasses, corresponding to various IC
types:

* ForIn
* Comparison ops
* Binary/Unary ops
* InstanceOf
* Calls

The feedback is gathered at serialization time and used in several places,
namely:

* Bytecode graph building,
* and its helper class JSTypeHintLowering (with its "early lowering")
* Native context specialization
* JSCallReducer

Design doc: https://docs.google.com/document/d/1JLG0VFV8xmsAIJexU19xzlbNyP51ONqfo_Gf_2DcPC8/edit?usp=sharing

Bug: v8:7790
Change-Id: I53c3d7a17f844384f38c4ee0f0b082c114217a02
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1710663
Commit-Queue: Georg Neis <neis@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63028}

From JSNativeContextSpecialization::ReduceKeyedLoadFromHeapConstant
to JSNativeContextSpecialization::ReduceElementLoadFromHeapConstant.

Change-Id: Ib07a6a4bd599dc71a9a100b2f1f6baef68acbe0b
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1728618Reviewed-by: Maya Lekova <mslekova@chromium.org>
Commit-Queue: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63027}

now that we are shipping this by default, we can remove the flag.

Change-Id: I298691df3eec934a5add1aa2a2748a0f3a884ab6
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1726452
Commit-Queue: Joshua Litt <joshualitt@chromium.org>
Reviewed-by: Sathya Gunasekaran  <gsathya@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63026}

The unittest for {WasmCodeManager} currently disables implicit
allocations for win64 unwind info, but still deals with the implicitly
allocated jump table. With the addition of a far jump table, this logic
would get even more complex.
Thus this CL introduces a testing flag on the {WasmCodeManager} to
disable all implicit allocations, and uses that instead in the
{WasmCodeManagerTest}.

R=mstarzinger@chromium.org

Bug: v8:9477
Change-Id: I45e4bc6b9fec6d7286bf6b45f778681ae0dba746
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1725622
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63025}

Now PropertyAccessBuilder::TryBuildLoadConstantDataField is
heap-access free.

Bug: v8:7790
Change-Id: Ibcc644270325d25da01af7f66e8a26fb57614718
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1725614
Commit-Queue: Maya Lekova <mslekova@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63024}

This reverts commit 159df248.

Reason for revert: Breaks large-classes-properties test (https://logs.chromium.org/logs/v8/buildbucket/cr-buildbucket.appspot.com/8906338563361079200/+/steps/Bisect_159df248/0/steps/Retry_-_isolates/0/logs/large-classes-properties/0)

Original change's description:
> [ic] Don't transition to premonomorphic state
> 
> We used to use premonomorphic state to delay initializing the ICs.
> This optimization was to avoid the cost of setting up handlers if the
> code executed only once. With lazy feedback allocation we no longer
> need this.
> 
> This cl also renames LoadIC_Uninitialized to LoadIC_Nofeedback and
> StoreIC_Uninitialized to StoreIC_Nofeedback since we now miss to
> runtime in the uninitialized state and use the builtin when there
> is no feedback.
> 
> 
> Change-Id: I1633e61ea74664da51348e362c34c47a017a264a
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1683525
> Commit-Queue: Mythri Alle <mythria@chromium.org>
> Reviewed-by: Toon Verwaest <verwaest@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#63020}

TBR=mythria@chromium.org,verwaest@chromium.org

Change-Id: I4fad4e8b881d4a3f8d12149e1797b217a317eaee
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1730995Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63023}

This reverts commit f5611402.

Reason for revert: arm64 sim MSAN failures (https://ci.chromium.org/p/v8/builders/ci/V8%20Linux%20-%20arm64%20-%20sim%20-%20MSAN/28059)

Original change's description:
> [ptr-compr][arm64] Temporarily enable pointer compression on arm64
> 
> ... and make sure that the arm64 ptr-compr bots proceed testing V8 without
> pointer compression in order to keep testing the other config.
> 
> Commented out the 'extra' variant since it was crashing. Opened a bug
> regarding that: https://bugs.chromium.org/p/v8/issues/detail?id=9568
> 
> Similar to x64's https://chromium-review.googlesource.com/c/v8/v8/+/1607654
> 
> Bug: v8:7703
> Change-Id: Ifd46b029bab34524f9f536dcdbd1574f2ddcbf37
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1724216
> Reviewed-by: Tamer Tas <tmrts@chromium.org>
> Reviewed-by: Michael Achenbach <machenbach@chromium.org>
> Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#63019}

TBR=machenbach@chromium.org,tmrts@chromium.org,solanes@chromium.org

Change-Id: I7d96c8aa83fcabff7e9a82e0556811398fedc34c
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:7703
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1730994Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63022}

This removes the explicit {kCallWithCallerSavedRegisters} opcode which
is just a regular call node with special handling for saving/restoring
caller saved registers before/after the call. This is now handled via
the {CallDescriptor::kCallerSavedRegisters} flag.

R=neis@chromium.org
BUG=v8:9396

Change-Id: Ie6421085eb2be8a067040222cd5215a9b1013048
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1728611Reviewed-by: Georg Neis <neis@chromium.org>
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63021}

We used to use premonomorphic state to delay initializing the ICs.
This optimization was to avoid the cost of setting up handlers if the
code executed only once. With lazy feedback allocation we no longer
need this.

This cl also renames LoadIC_Uninitialized to LoadIC_Nofeedback and
StoreIC_Uninitialized to StoreIC_Nofeedback since we now miss to
runtime in the uninitialized state and use the builtin when there
is no feedback.


Change-Id: I1633e61ea74664da51348e362c34c47a017a264a
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1683525
Commit-Queue: Mythri Alle <mythria@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63020}

... and make sure that the arm64 ptr-compr bots proceed testing V8 without
pointer compression in order to keep testing the other config.

Commented out the 'extra' variant since it was crashing. Opened a bug
regarding that: https://bugs.chromium.org/p/v8/issues/detail?id=9568

Similar to x64's https://chromium-review.googlesource.com/c/v8/v8/+/1607654

Bug: v8:7703
Change-Id: Ifd46b029bab34524f9f536dcdbd1574f2ddcbf37
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1724216Reviewed-by: Tamer Tas <tmrts@chromium.org>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63019}

Bug: v8:7790

Change-Id: Icd0194924d7b0aa58f5b7ee74028cec9f5c39564
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1715460Reviewed-by: Georg Neis <neis@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Commit-Queue: Maya Lekova <mslekova@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63018}

Rolling v8/build: https://chromium.googlesource.com/chromium/src/build/+log/496479d..bc4a3ca

Rolling v8/third_party/catapult: https://chromium.googlesource.com/catapult/+log/2568b37..471a922

Rolling v8/third_party/depot_tools: https://chromium.googlesource.com/chromium/tools/depot_tools/+log/c075833..447b45d

TBR=machenbach@chromium.org,tmrts@chromium.org

Change-Id: I5e3e3bf84ca86a7b7c702555f8a4206b0b08f5a3
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1729355Reviewed-by: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Commit-Queue: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/master@{#63017}

Bug: v8:8425
Change-Id: I4c883726daee1ab244e4bc2ce202cacf9bd3d50c
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1726400
Auto-Submit: Zhi An Ng <zhin@chromium.org>
Reviewed-by: Deepti Gandluri <gdeepti@chromium.org>
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63016}

The mask should cover the sign (1 bit), exponent (11 bits) and quiet bit (1 bit) of significand, total of 13 bits. The old mask only covered 9 bits.

Change-Id: I6ec402b4cec34978eac8fa3e5452ad22540a93ce
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1726984Reviewed-by: Bill Budge <bbudge@chromium.org>
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63015}

Instead of having fast path for proxy only in Reflect.deleteProperty, it
is also in delete operator.

Bug: v8:6664
Change-Id: I3db919953e31f51a5dc4a504062bd691a6e17446
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1717660
Commit-Queue: Z Nguyen-Huu <duongn@microsoft.com>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Reviewed-by: Simon Zünd <szuend@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63014}

Wrapped functions don't recompile properly with lazy source positions so
just force them to always collect the source positions.

Fixes cctest/test-compiler/CompileFunctionInContext in the presence of
--enable-lazy-source-positions and --stress-lazy-source-positions.

Bug: v8:8510
Change-Id: I2402a441d4930be11dc037c6041cb577a63a3529
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1709427
Commit-Queue: Dan Elphick <delphick@chromium.org>
Auto-Submit: Dan Elphick <delphick@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63013}

Bug: v8:9536
Change-Id: Ie9c47493ab29f604d6e43ef318e08618ee527fc3
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1728329Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Commit-Queue: Deepti Gandluri <gdeepti@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63012}

This reverts commit df8e6177.

Reason for revert: Multiple flakes in apparently related areas:

https://logs.chromium.org/logs/v8/buildbucket/cr-buildbucket.appspot.com/8906409837768155568/+/steps/Check__flakes_/0/logs/BackingStoreTest.RacyGrowWasmMem.../0

Original change's description:
> "Reland x3 [arraybuffer] Rearchitect backing store ownership"
> 
> This is a reland of bc33f5ae
> 
> Original change's description:
> > [arraybuffer] Rearchitect backing store ownership
> >
> > This CL completely rearchitects the ownership of array buffer backing stores,
> > consolidating ownership into a {BackingStore} C++ object that is tracked
> > throughout V8 using unique_ptr and shared_ptr where appropriate.
> >
> > Overall, lifetime management is simpler and more explicit. The numerous
> > ways that array buffers were initialized have been streamlined to one
> > Attach() method on JSArrayBuffer. The array buffer tracker in the
> > GC implementation now manages std::shared_ptr<BackingStore> pointers,
> > and the construction and destruction of the BackingStore object itself
> > handles the underlying page or embedder-allocated memory.
> >
> > The embedder API remains unchanged for now. We use the
> > v8::ArrayBuffer::Contents struct to hide an additional shared_ptr to
> > keep the backing store alive properly, even in the case of aliases
> > from live heap objects. Thus the embedder has a lower chance of making
> > a mistake. Long-term, we should move the embedder to a model where they
> > manage backing stores using shared_ptr to an opaque backing store object.
> 
> R=​mlippautz@chromium.org
> BUG=v8:9380,v8:9221,chromium:986318
> TBR=ulan@chromium.org
> 
> Change-Id: I6c49e2425029b5664ef1c68dab8b5146f4ed0ff2
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1719191
> Reviewed-by: Ben Titzer <titzer@chromium.org>
> Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
> Commit-Queue: Ben Titzer <titzer@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#63007}

TBR=mstarzinger@chromium.org,titzer@chromium.org,mlippautz@chromium.org

Change-Id: If0266e5893b1325a332d5986337fa7ece2cb6943
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:9380, v8:9221, chromium:986318
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1729549Reviewed-by: Francis McCabe <fgm@chromium.org>
Commit-Queue: Francis McCabe <fgm@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63011}

R=ulan@chromium.org

Bug: v8:9380
No-Try: true
Change-Id: I319bbc607a738d78cb797691bcfcb9484f416324
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1728619
Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63010}

This is a reland of 4b15b984

Updates since original: fix an arithmetic overflow bug, remove an invalid
DCHECK, add a unit test that would trigger that DCHECK.

Original change's description:
> [regexp] Better quick checks on loop entry nodes
>
> Like the predecessor change https://crrev.com/c/v8/v8/+/1702125 , this
> change is inspired by attempting to exit earlier from generated RegExp
> code, when no further matches are possible because any match would be
> too long. The motivating example this time is the following expression,
> which tests whether a string of Unicode playing cards has five of the
> same suit in a row:
>
> /([🂡-🂮]{5})|([🂱-🂾]{5})|([🃁-🃎]{5})|([🃑-🃞]{5})/u
>
> A human reading this expression can readily see that any match requires
> at least 10 characters (5 surrogate pairs), but the LoopChoiceNode for
> each repeated option reports its minimum distance to the end of a match
> as zero. This is correct, because the LoopChoiceNode's behavior depends
> on additional state (the loop counter). However, the preceding node, a
> SET_REGISTER action that initializes the loop counter, could confidently
> state that it consumes at least 10 characters. Furthermore, when we try
> to emit a quick check for that action, we could follow only paths from
> the LoopChoiceNode that are possible based on the minimum iteration
> count. This change implements both of those "could"s.
>
> I expect this improvement to apply pretty broadly to expressions that
> use minimum repetition counts and that don't meet the criteria for
> unrolling. In this particular case, I get about 12% improvement on the
> overall UniPoker test, due to reducing the execution time of this
> expression by 85% and the execution time of another similar expression
> that checks for n-of-a-kind by 20%.
>
> Bug: v8:9305
>
> Change-Id: I319e381743967bdf83324be75bae943fbb5dd496
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1704941
> Commit-Queue: Seth Brenith <seth.brenith@microsoft.com>
> Reviewed-by: Jakob Gruber <jgruber@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#62963}

Bug: v8:9305
Change-Id: I992070d383009013881bf778242254c27134b650
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1726674Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Seth Brenith <seth.brenith@microsoft.com>
Cr-Commit-Position: refs/heads/master@{#63009}

This is a reland of 517ab73f

Updates since original: now compressed pointers passed to the function
GetObjectProperties are required to be sign-extended. Previously, the
function allowed zero-extended values, but that led to ambiguity on
pointers like 0x88044919: is it compressed or is the heap range actually
centered on 0x100000000?

Original change's description:
> Add postmortem debugging helper library
>
> This change begins to implement the functionality described in
> https://docs.google.com/document/d/1evHnb1uLlSbvHAAsmOXyc25x3uh1DjgNa8u1RHvwVhk/edit#
> for investigating V8 state in crash dumps.
>
> This change adds a new library, v8_debug_helper, for providing platform-
> agnostic assistance with postmortem debugging. This library can be used
> by extensions built for debuggers such as WinDbg or lldb. Its public API
> is described by debug-helper.h; currently the only method it exposes is
> GetObjectProperties, but we'd like to add more functionality over time.
> The API surface is restricted to plain C-style structs and pointers, so
> that it's easy to link from a debugger extension built with a different
> toolchain.
>
> This change also adds a new cctest file to exercise some basic
> interaction with the new library.
>
> The API function GetObjectProperties takes an object pointer (which
> could be compressed, or weak, or a SMI), and returns a string
> description of the object and a list of properties the object contains.
> For now, the list of properties is entirely based on Torque object
> definitions, but we expect to add custom properties in future updates so
> that it can be easier to make sense of complex data structures such as
> dictionaries.
>
> GetObjectProperties does several things that are intended to generate
> somewhat useful results even in cases where memory may be corrupt or
> unavailable:
> - The caller may optionally provide a type string which will be used if
>   the memory for the object's Map is inaccessible.
> - All object pointers are compared against the list of known objects
>   generated by mkgrokdump. The caller may optionally provide the
>   pointers for the first pages of various heap spaces, to avoid spurious
>   matches. If those pointers are not provided, then any matches are
>   prefixed with "maybe" in the resulting description string, such as
>   "maybe UndefinedValue (0x4288000341 <Oddball>)".
>
> Bug: v8:9376
>
> Change-Id: Iebf3cc2dea3133c7811bcefcdf38d9458b02fded
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1628012
> Commit-Queue: Seth Brenith <seth.brenith@microsoft.com>
> Reviewed-by: Yang Guo <yangguo@chromium.org>
> Reviewed-by: Michael Stanton <mvstanton@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#62882}

Bug: v8:9376
Change-Id: I866a1cc9d4c34bfe10c7b98462451fe69763cf3f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1717090Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Reviewed-by: Michael Stanton <mvstanton@chromium.org>
Commit-Queue: Seth Brenith <seth.brenith@microsoft.com>
Cr-Commit-Position: refs/heads/master@{#63008}

This is a reland of bc33f5ae

Original change's description:
> [arraybuffer] Rearchitect backing store ownership
>
> This CL completely rearchitects the ownership of array buffer backing stores,
> consolidating ownership into a {BackingStore} C++ object that is tracked
> throughout V8 using unique_ptr and shared_ptr where appropriate.
>
> Overall, lifetime management is simpler and more explicit. The numerous
> ways that array buffers were initialized have been streamlined to one
> Attach() method on JSArrayBuffer. The array buffer tracker in the
> GC implementation now manages std::shared_ptr<BackingStore> pointers,
> and the construction and destruction of the BackingStore object itself
> handles the underlying page or embedder-allocated memory.
>
> The embedder API remains unchanged for now. We use the
> v8::ArrayBuffer::Contents struct to hide an additional shared_ptr to
> keep the backing store alive properly, even in the case of aliases
> from live heap objects. Thus the embedder has a lower chance of making
> a mistake. Long-term, we should move the embedder to a model where they
> manage backing stores using shared_ptr to an opaque backing store object.

R=mlippautz@chromium.org
BUG=v8:9380,v8:9221,chromium:986318
TBR=ulan@chromium.org

Change-Id: I6c49e2425029b5664ef1c68dab8b5146f4ed0ff2
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1719191Reviewed-by: Ben Titzer <titzer@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Commit-Queue: Ben Titzer <titzer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63007}

Port 556e4859

Original Commit Message:

    Instead of storing the values of the single precision floating point registers,
    get their values from the aliased double precision registers.

    This saves, on arm64, 184 bytes per deoptimisation kind function (552 in total)
    and 128 bytes in the RegisterValues class.

R=joey.gouly@arm.com, joransiu@ca.ibm.com, jyan@ca.ibm.com, michael_dawson@ca.ibm.com
BUG=
LOG=N

Change-Id: If38a721cfaefb7980902f4f963119cb88061e342
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1726857Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Commit-Queue: Milad Farazmand <miladfar@ca.ibm.com>
Cr-Commit-Position: refs/heads/master@{#63006}

With the arrival of generic structs (https://chromium-review.googlesource.com/c/v8/v8/+/1714868) the existing type inference procedure for generic calls became incomplete, since it could not infer types that were only constrained as part of generic types. For instance, given

  struct Box<T: Type> { ... }

  macro unbox<T: type>(box: Box<T>): T

the type argument (Smi) at the following call site

  const box: Box<Smi> = ...;
  unbox(box);

could not be inferred.

This CL re-implements the inference procedure and documents the semantics of type argument inference in Torque a bit more clearly.

R=tebbi@chromium.org

Change-Id: I868f16afbd9864b9c810ac49bc1639b467df939c
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1720812
Commit-Queue: Georg Schmid <gsps@google.com>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63005}

Removes static modifier from global inline functions defined in
globals.h.

R=rmcilroy@chromium.org

Bug: v8:9396
Change-Id: Ieacbcbf592d219fb50ab2d23dfbaba27246fb7ae
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1728610Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Commit-Queue: Dan Elphick <delphick@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63004}

Change-Id: Ica3d8ca233278e50e390aad37138942d23b5b8b1
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1728612Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63003}

On Windows ARM64, OS stack walking does not work because the V8 ARM64 backend
doesn't emit unwinding info and also because it doesn't emit ABI compliant
stack frames. This was fixed for Windows X64 (https://crrev.com/c/1469329) and
documented below:

https://docs.google.com/document/d/1-wf50jFlii0c_Pr52lm2ZU-49m220nhYMrHDi3vXnh0

This problem can be fixed similarly for Windows ARM64 by observing that V8
frames usually all have the same prolog which maintains a chain via frame
pointer (fp or x29 register).

stp fp, lr, [sp, ...]

One exception is JSEntry which stops fp pointer chain and needs to be handled
specially.

So it is possible to define XDATA with UNWIND_CODE which specify how Windows
should walk through V8 dynamic frames. The same as X64, since V8 Code objects
are all allocated in the same code-range for an Isolate, it is possible to
register at most 2 XDATA and a group of PDATA entries to cover stack walking
for all the code generated inside that code-range. This is more than 1
PDATA/XDATA because according to the Windows ARM64 exeption handling document,
1 PDATA can cover less than 1MB code range (see below doc).

https://docs.microsoft.com/en-us/cpp/build/arm64-exception-handling

This PR implements stackwalk for Windows ARM64 to be on par with X64, including
embedded builtins, jitted code and wasm jitted code, but not including register
handler for handling exception only, because there is no backward compatibility
to maintain for Windows ARM64 which was released since 1709 windows build.

Bug: chromium:893460
Change-Id: Ic74cbdad8af5cf342185030a4c53796f12ea5429
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1701133Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63002}

Rolling v8/test/wasm-js/data: https://chromium.googlesource.com/external/github.com/WebAssembly/spec/+log/b0c936c..a221f25

[spec] Upgrade to IEEE 754-2019 (#1050) (Andreas Rossberg)
https://chromium.googlesource.com/external/github.com/WebAssembly/spec/+/a221f25

TBR=ahaas@chromium.org,clemensh@chromium.org

Change-Id: Id90c6e3228c4e5943e8bb49bc82fd4a9b01c424f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1726578Reviewed-by: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Commit-Queue: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/master@{#63001}

Rolling v8/build: https://chromium.googlesource.com/chromium/src/build/+log/a9a0d9b..496479d

Rolling v8/third_party/catapult: https://chromium.googlesource.com/catapult/+log/ff7e2eb..2568b37

Rolling v8/tools/clang: https://chromium.googlesource.com/chromium/src/tools/clang/+log/57e1363..8215b08

TBR=machenbach@chromium.org,tmrts@chromium.org

Change-Id: I54127742991c381ebbac0e8688f7dafe50621ac2
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1726577Reviewed-by: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Commit-Queue: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/master@{#63000}

The s390 port uses the auxvector APIs to detect hardware/OS
support for various z/Architecture features.  These checks
only make sense if we are running native, non-simulator mode.

Moving the include<auxv.h> under V8_HOST_ARCH_S390 enables
compilation of s390 simulation on platforms that do not have auxv.h
header available.

R=miladfar@ca.ibm.com,jyan@ca.ibm.com

Change-Id: I685681a4f8786509beb181d8ae63876b3a4235b2
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1726844Reviewed-by: Milad Farazmand <miladfar@ca.ibm.com>
Commit-Queue: Joran Siu <joransiu@ca.ibm.com>
Cr-Commit-Position: refs/heads/master@{#62999}

port 556e4859 https://crrev.com/c/1669687

Original Commit Message:

    Instead of storing the values of the single precision floating point registers,
    get their values from the aliased double precision registers.

    This saves, on arm64, 184 bytes per deoptimisation kind function (552 in total)
    and 128 bytes in the RegisterValues class.

Change-Id: Ic178de717d27a63b3f510b3a93e8f33a1730dc8b
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1725669Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Commit-Queue: Yu Yin <xwafish@gmail.com>
Cr-Commit-Position: refs/heads/master@{#62998}

REX prefix should be after mandatory prefix and before opcode.

Change-Id: I9829384d7d617d3be203026ae84ffa30aaef6d2e
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1726983
Commit-Queue: Bill Budge <bbudge@chromium.org>
Auto-Submit: Zhi An Ng <zhin@chromium.org>
Reviewed-by: Bill Budge <bbudge@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62997}

Original CL:
> [wasm] Simplify module creation
>
> This includes WasmEngine::NewNativeModule() and
WasmModuleObject::New().
> The intent is to make the various ways of creating a module (sync,
> async, deserialize, import) more similar.
>
> After this change, a NativeModule will always be created before a
> WasmModuleObject. This will make it easier to look up a cached
> NativeModule given its wire bytes.
>
> The following changes are made:
>
> * Use WasmCodeManager::EstimateNativeModuleCodeSize() to find the code
>   size estimate by default. A different code size estimate is only
used in
>   tests.
> * Change CompileJsToWasmWrappers() to allocate a new FixedArray
instead of
>   assuming the array was created with the correct size. This
simplifies
>   WasmModuleObject::New(), and matches what CompileToNativeModule()
>   does.
> * Remove the WasmModuleObject::New() constructor that creates a
>   NativeModule. This case was only used in DeserializeNativeModule()
and
>   in test code.
>
> Change-Id: I6bdfc425057f92de11abbbf702d052d40aa8267d
> Reviewed-on:
https://chromium-review.googlesource.com/c/v8/v8/+/1717497
> Commit-Queue: Ben Smith <binji@chromium.org>
> Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#62925}

R=ahaas@chromium.org, clemensh@chromium.org
CC=binji@chromium.org

Change-Id: I03aa901a1df65af28f864d9aabe2b134ea132e99
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1724213
Commit-Queue: Ben Smith <binji@chromium.org>
Reviewed-by: Ben Smith <binji@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62996}

 - Add new instruction variants for psllq, psrlq (x64), vshl (ARM)
 - Add instruction selection, code generation for register shifts
 - Remove implicit immediate for shift operators
 - Fix interpreter, tests

Bug:v8:8934, v8:8460

Change-Id: I3481d7ba34a34f7792ff1a61d4a726a1a9abab8d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1722198
Commit-Queue: Deepti Gandluri <gdeepti@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Bill Budge <bbudge@chromium.org>
Reviewed-by: Zhi An Ng <zhin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62995}

Numeric separators are not allowed in NonOctalDecimalIntegerLiterals.

Bug: v8:9437
Change-Id: Ic62b35b361de36fc622e207c140c365665021029
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1722194
Commit-Queue: Joshua Litt <joshualitt@chromium.org>
Reviewed-by: Sathya Gunasekaran <gsathya@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62994}

The DCHECK related to a time when dictionary mode prototypes were the payload
of complex data driven handlers. Now the additional data is used to hold
entirely different kinds of objects. The DCHECK made no sense anymore. Cleaning
up the names makes this clearer.

Bug: chromium:986187
Change-Id: I7173d7d2824396c04c01acb4ceb74693ee9ce6b8
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1724215
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62993}

D8 workers were leaking all messages due to a missing HandleScope
within the message loop. Add one to fix leaks.

R=verwaest@chromium.org
BUG=v8:9524

Change-Id: I2f2f6ba0b8c58bf38bf68b7464dffdf1d826a29d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1724212Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Commit-Queue: Ben Titzer <titzer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62992}

Do not pass the deoptimization index in a register, instead infer it
from the address we made the deoptimization call from. This makes the
deoptimization exit sequence one instruction long instead of two.

This requires emitting all deoptimization exits at the end of the
function in a contiguous block, making sure no constant or veneer
pools are emitted in between. This means that soft deoptimizations
require an additional branch to the end of the function, which
counteracts the removal of the move instruction, however soft
deoptimizations are rare compared to eager and lazy ones.

This reduces the code size of optimised functions for benchmarks like
Octane and ARES-6 by about 4%.

Change-Id: I771f9104a07de7931a4bb9c5836e25fb55b1a2a4
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1714876
Commit-Queue: Georgia Kouveli <georgia.kouveli@arm.com>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62991}

This method will be used for a test with multiple code spaces, to
encode large function indexes. The current implementation in
{wasmI32Const} just always uses 5 bytes for encoding the LEB value.
This CL adds a {wasmSignedLeb} function which properly encodes the
value, and adds tests for that.

Drive-by: Clean up the rest of {test-wasm-module-builder.js}.

R=mstarzinger@chromium.org

Bug: v8:9477
Change-Id: Ide2d90eed9d40aa28df680fbb413275346d9c0b6
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1725623Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62990}