Provide a stub `third_party_heap::Heap` implementation to work around
linker erors with Visual Studio.

cl.exe in debug mode seems to eliminate dead code not as aggressively
as clang or gcc, resulting in references to `third_party_heap::Heap`
remaining in unreachable code paths.

Refs: https://github.com/bnoordhuis/v8-cmake/issues/10
Bug: v8:10427
Change-Id: I61fde11697adc663b182f60c132eda435a7f11bd
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2159490
Commit-Queue: Ben Noordhuis <info@bnoordhuis.nl>
Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
Auto-Submit: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67293}

- Adds builtins to convert between Int32/Float64 and JS Number.
  - WasmInt32ToHeapNumber (bypass SMI test)
  - WasmFloat64ToNumber
- Adds builtins to convert between Tagged and Int32/Float64.
  - WasmTaggedNonSmiToInt32 (bypass SMI test)
  - WasmTaggedToFloat64

- Uses these builtins in Wasm import and export wrappers instead of
  generating the equivalent code inline.

Results of running Wasm/import-export-wrappers.js Benchmark:
https://docs.google.com/document/d/1QIB0xnqdJFRsOJKQYZ8DZgzWn4WysybgugbcO0sYcQA/edit?usp=sharing

NOTE: CL will need to be rebased after linkage fix lands.

Bug: v8:10070

Change-Id: Ib34507fcd18bdf80938b5707310a5a4f76cdec72
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2099445Reviewed-by: Andreas Haas <ahaas@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Commit-Queue: Bill Budge <bbudge@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67292}

This reverts commit 80843eda.

Reason for revert: Causes compilation failure on macs

https://ci.chromium.org/p/v8/builders/ci/Mac%20V8%20FYI%20Release%20(Intel)/8934?


Original change's description:
> [torque] Allow storing to bitfield structs that are stored in Smis
> 
> This change:
> 1. Updates the Torque compiler to allow direct access to bitfields that
>    are packed within Smi values, which previously would have required a
>    separate untagging step,
> 2. Updates JSRegExpStringIterator to represent its flags in Torque,
> 3. Adds reduction cases in MachineOperatorReducer for when the input to
>    a branch or the left-hand side of a Word32Equals is based on a 64-bit
>    shift-and-mask operation which has been truncated to 32 bits, as is
>    the case in the code generated by step 1, and
> 4. Adds a reduction case in MachineOperatorReducer to remove an extra
>    Word64And operation added by step 1.
> 
> Bug: v8:7793
> Change-Id: Ib4ac2def6211b3cae6be25a8b2a644be5c7d6d3f
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2119225
> Commit-Queue: Seth Brenith <seth.brenith@microsoft.com>
> Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#67290}

TBR=tebbi@chromium.org,seth.brenith@microsoft.com,nicohartmann@chromium.org

Change-Id: Ifa683c92631291c9437438682b6efb2e12862682
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:7793
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2159730Reviewed-by: Francis McCabe <fgm@chromium.org>
Commit-Queue: Francis McCabe <fgm@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67291}

This change:
1. Updates the Torque compiler to allow direct access to bitfields that
   are packed within Smi values, which previously would have required a
   separate untagging step,
2. Updates JSRegExpStringIterator to represent its flags in Torque,
3. Adds reduction cases in MachineOperatorReducer for when the input to
   a branch or the left-hand side of a Word32Equals is based on a 64-bit
   shift-and-mask operation which has been truncated to 32 bits, as is
   the case in the code generated by step 1, and
4. Adds a reduction case in MachineOperatorReducer to remove an extra
   Word64And operation added by step 1.

Bug: v8:7793
Change-Id: Ib4ac2def6211b3cae6be25a8b2a644be5c7d6d3f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2119225
Commit-Queue: Seth Brenith <seth.brenith@microsoft.com>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67290}

We give the optimized code another chance on soft deopts in TurboProp.
If the deopt is happening on infrequently taken paths, then this will
let us reuse the optimized code for the subsequent executions. If the
soft deopts are happening multiple times on the same code, then we would
discard the optimized code. The number of deopts we would wait is
controlled by FLAG_reuse_opt_code_count.

BUG=v8:10433

Change-Id: Iaadea4cffde7d7d55be4875c9586694dca64957c
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2093503
Commit-Queue: Mythri Alle <mythria@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67289}

Bug: v8:7748
Change-Id: I80265c7070dc7ec421bf53aa717a727c144b0699
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2152844
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67288}

This relands commit 387d85ad.

This was passing in the simulator because of the typo in
simulator-arm.cc. The instr->Bit(7,6) call is incorrect, it should be
Bit (no s). I don't really know what it resolves to, but the effect is
that we get src_unsigned is false when we expect it to be true.

With the simulator fix, we get the same error as non-simulator runs. The
fix is in liftoff-assembler-arm.h, we need to be passing both source and
dst data types to vmovqn. This was already done correctly in
code-generator-arm, but I was careless in copying the logic...

Bug: v8:9909

Original change's description:
> [wasm-simd][liftoff][arm][arm64] Implement integer narrowing
>
> Bug: v8:9909
> Change-Id: I0664df45fe399bfa018ff8bcacdbdae66944ed29
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2154834
> Reviewed-by: Clemens Backes <clemensb@chromium.org>
> Commit-Queue: Zhi An Ng <zhin@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#67254}

Change-Id: If17f13aae40569174635283abec5ea1358286f55
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2157799Reviewed-by: Clemens Backes <clemensb@chromium.org>
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Auto-Submit: Zhi An Ng <zhin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67287}

Change-Id: I485596563e557f459d846adcdc3046c72b27c17e
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2159486
Commit-Queue: Liviu Rau <liviurau@chromium.org>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67286}

Bug: None
Change-Id: I78bb392d78c9ec968a0763dd9767f4b0ceb374a9
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2157380Reviewed-by: Georg Neis <neis@chromium.org>
Commit-Queue: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67285}

Port 6f7b4c7f

R=jing.bao@intel.com, joransiu@ca.ibm.com, jyan@ca.ibm.com, michael_dawson@ca.ibm.com
BUG=
LOG=N

Change-Id: Id707ca1de4c4ef71d46192e97ea82453fbf45482
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2158843Reviewed-by: Junliang Yan <jyan@ca.ibm.com>
Commit-Queue: Milad Farazmand <miladfar@ca.ibm.com>
Cr-Commit-Position: refs/heads/master@{#67284}

Change-Id: I5cf7c8eb00bb0cb3437ae8d82978543f3191e34a
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2158844Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Milad Farazmand <miladfar@ca.ibm.com>
Cr-Commit-Position: refs/heads/master@{#67283}

This reverts commit 5c4b8056.

Reason for revert: https://ci.chromium.org/p/v8/builders/ci/V8%20Clusterfuzz%20Linux%20MSAN%20no%20origins/14661

Original change's description:
> [snapshot] Extract more files
> 
> This moves:
> 
> - ExternalReferenceEncoder to codegen/external-reference-encoder.h
> - SerializerDeserializer to snapshot/serializer-deserializer.h
> - Checksum() to snapshot/snapshot-utils.h
> 
> serializer-common.h and .cc are removed.
> 
> Tbr: clemensb@chromium.org,ulan@chromium.org
> Bug: v8:10416
> Change-Id: I36a242dcc1ad8833374aa567f73e0d4a75632c58
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2144118
> Commit-Queue: Jakob Gruber <jgruber@chromium.org>
> Reviewed-by: Jakob Gruber <jgruber@chromium.org>
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Reviewed-by: Clemens Backes <clemensb@chromium.org>
> Reviewed-by: Dan Elphick <delphick@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#67281}

TBR=ulan@chromium.org,jgruber@chromium.org,clemensb@chromium.org,delphick@chromium.org

Change-Id: I718ca43a31d3ca937d700eab9bacc163e4598283
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:10416
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2157383Reviewed-by: Sathya Gunasekaran  <gsathya@chromium.org>
Commit-Queue: Sathya Gunasekaran  <gsathya@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67282}

This moves:

- ExternalReferenceEncoder to codegen/external-reference-encoder.h
- SerializerDeserializer to snapshot/serializer-deserializer.h
- Checksum() to snapshot/snapshot-utils.h

serializer-common.h and .cc are removed.

Tbr: clemensb@chromium.org,ulan@chromium.org
Bug: v8:10416
Change-Id: I36a242dcc1ad8833374aa567f73e0d4a75632c58
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2144118
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Reviewed-by: Dan Elphick <delphick@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67281}

Recompute heap limits while all threads are still stopped. Otherwise
setting the limits races with concurrent background threads performing
allocations.

Bug: v8:10315
Change-Id: I17e711b960e1fde05adb4f4b794f813b94190ef1
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2157375Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Dominik Inführ <dinfuehr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67280}

snapshot.h is intended to be the public header for the snapshot
component, and not the right place for private declarations. This moves
them into a new SnapshotImpl class in snapshot.cc (previously named
snapshot-common.cc).

Bug: v8:10416
Change-Id: If34ad8d6e189050686942488fb8e99c3d310beee
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2144062
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Dan Elphick <delphick@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67279}

- Fixes includes to be relative to include/ which allows embedders
  to just add V8's include directory to get started.
- Adds public target for the library as "cppgc".

Bug: chromium:1056170
Change-Id: Iec9b644e20016a5d7281275b739821a050fd2540
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2157366Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67278}

We are compiling V8 using devtoolset-8 and it is generating a new
compilation error related to String Truncation:

error: ‘char* strncpy(char*, const char*, size_t)’ output truncated copying between 1 and 15 bytes from a string of length 15 [-Werror=stringop-truncation]
          strncpy(buffer, unicode_utf8, i);

Which basically means the null terminating character was not added to
the end of the buffer:
https://developers.redhat.com/blog/2018/05/24/detecting-string-truncation-with-gcc-8/

This CL will changes 2 uses of "strncpy" to "memcpy" as strings
are being copied partially and `\n` being added at a later stage.

Change-Id: I3656afb00463d70ddb8700a487a1978b793e1d09
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2155038Reviewed-by: Andreas Haas <ahaas@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Commit-Queue: Milad Farazmand <miladfar@ca.ibm.com>
Cr-Commit-Position: refs/heads/master@{#67277}

The former is backed by a runtime function for now.
No Liftoff or interpreter implementation yet.

Bug: v8:7748
Change-Id: If2e1bf6e7a5267c5e64529bb5a686e548682e80a
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2154199Reviewed-by: Andreas Haas <ahaas@chromium.org>
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67276}

This reverts commit e1b93a4f.

Reason for revert: MSVC failing https://ci.chromium.org/p/v8/builders/ci/V8%20Win64%20-%20msvc/13274

Original change's description:
> Reland^4 "[parser] Introduce UnoptimizedCompileFlags"
> 
> This is a reland of 313d4844
> which was a reland of 0a59e0cb
> which was a reland of 146f5375
> which was a reland of d91679bf
> 
> Manually zero out flags with memset, since GCC appears not to initialize
> the bitfield values to zero even with a default constructor.
> 
> Original change's description:
> > [parser] Introduce UnoptimizedCompileFlags
> >
> > UnoptimizedCompileFlags defines the input flags shared between parse and
> > compile (currently parse-only). It is set initially with some values, and
> > is immutable after being passed to ParseInfo (ParseInfo still has getters
> > for the fields, but no setters).
> >
> > Since a few of the existing flags were output flags, ParseInfo now has a
> > new output_flags field, which will eventually migrate to a ParseOutputs
> > structure.
> >
> > Bug: v8:10314
> > Change-Id: If3890a5fad883bca80a97bf9dfe44d91797dc286
> > Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2096580
> > Commit-Queue: Leszek Swirski <leszeks@chromium.org>
> > Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> > Reviewed-by: Simon Zünd <szuend@chromium.org>
> > Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#66782}
> 
> TBR=ulan@chromium.org,szuend@chromium.org,rmcilroy@chromium.org
> 
> Bug: v8:10314
> Change-Id: I23bd6f9f14e9d0bbdde91aad46be1a646fd9647d
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2157372
> Reviewed-by: Leszek Swirski <leszeks@chromium.org>
> Commit-Queue: Leszek Swirski <leszeks@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#67271}

TBR=ulan@chromium.org,rmcilroy@chromium.org,leszeks@chromium.org,szuend@chromium.org

Change-Id: I0f41e847d4edae67e131cc6d0f782137ab73bac2
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:10314
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2157377Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67275}

From several runtime functions, this was still missing. For some, it
shouldn't really matter, but some runtime functions (e.g. DebugBreak)
can call back into JS to wasm, and there it matters.

As it never hurts to clear and re-set the flag, this CL consistently
resets the flag for all runtime functions called from wasm code. For
runtime functions that are called from outside of wasm (e.g. from
wrappers), we add a DCHECK instead that the flag is not set. There is
one exception (WasmThrowTypeError), which is called both from wasm code
and from wrappers. In this case it's OK, I added a comment saying why.

Drive-by: Remove obsolete comments (from a time where this clearing
was still optional in some cases).

R=ahaas@chromium.org

Bug: v8:10389
Change-Id: Id4ec92a42e89005276b42c145fe3572eb459d220
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2157026Reviewed-by: Andreas Haas <ahaas@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67274}

Unused so far.

Bug: v8:7748
Change-Id: I8ee905614227c5517fa19088f76f947d2caadc3b
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2152843
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67273}

Port 6f7b4c7f
https://crrev.com/c/2154330

Change-Id: I1788a3f6ca30bb684efa182f5e4e40bb3052c052
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2156711Reviewed-by: Clemens Backes <clemensb@chromium.org>
Commit-Queue: Zhao Jiazhong <zhaojiazhong-hf@loongson.cn>
Cr-Commit-Position: refs/heads/master@{#67272}

This is a reland of 313d4844
which was a reland of 0a59e0cb
which was a reland of 146f5375
which was a reland of d91679bf

Manually zero out flags with memset, since GCC appears not to initialize
the bitfield values to zero even with a default constructor.

Original change's description:
> [parser] Introduce UnoptimizedCompileFlags
>
> UnoptimizedCompileFlags defines the input flags shared between parse and
> compile (currently parse-only). It is set initially with some values, and
> is immutable after being passed to ParseInfo (ParseInfo still has getters
> for the fields, but no setters).
>
> Since a few of the existing flags were output flags, ParseInfo now has a
> new output_flags field, which will eventually migrate to a ParseOutputs
> structure.
>
> Bug: v8:10314
> Change-Id: If3890a5fad883bca80a97bf9dfe44d91797dc286
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2096580
> Commit-Queue: Leszek Swirski <leszeks@chromium.org>
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Reviewed-by: Simon Zünd <szuend@chromium.org>
> Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#66782}

TBR=ulan@chromium.org,szuend@chromium.org,rmcilroy@chromium.org

Bug: v8:10314
Change-Id: I23bd6f9f14e9d0bbdde91aad46be1a646fd9647d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2157372Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67271}

Refactors out the allocation and space merging parts of OffThreadFactory
into a new OffThreadHeap class. This allows a separation of concerns
between allocating/merging and initializing, and future-proofs the
factory code against off-thread allocation implementation changes (e.g.
LocalHeap).

Bug: chromium:1011762
Change-Id: I876906dbfd50f8aafe56af2e63e5fe35e4f7f8e9
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2157369
Auto-Submit: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67270}

The intent of this work is to create a clean interface header file for
the snapshot component. As a first step, move SerializedData and
SnapshotData into their own dedicated files.

Bug: v8:10416
Change-Id: I95af08508555a2ec3c2364094b81a76e3e6bb38a
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2144117
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Dan Elphick <delphick@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67269}

... between the interpreter and generated code.

Prior to this CL, pre- and post conditions on the output register
array differed between the interpreter and generated code.

Interpreter
Pre: `output` fits captures and temporary registers.
Post: None.

Generated code
Pre:  `output` fits capture registers.
Post: `output` is modified if and only if the match succeeded.

This CL changes the interpreter to match generated code pre- and
post conditions by allocating space for temporary registers inside
the interpreter.

Drive-by: Add MaxRegisterCount, RegistersForCaptureCount helpers.

Bug: chromium:1067270
Change-Id: I2900ef2f31207d817ec7ead3e0e2215b23b398f0
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2135642
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67268}

Destroy the weak script handle from a custom finalizer, to ensure that
this is done from the main thread.

R=clemensb@chromium.org

Bug: v8:10417
Change-Id: I76a27c4a6db5ef4d189febcf9d0f81f9fd6c220d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2151347Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Commit-Queue: Thibaud Michaud <thibaudm@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67267}

This reverts commit 313d4844.

Reason for revert: https://ci.chromium.org/p/v8/builders/ci/V8%20Linux%20gcc/6354

Original change's description:
> Reland^3 "[parser] Introduce UnoptimizedCompileFlags"
> 
> This is a reland of 0a59e0cb
> which was a reland of 146f5375
> which was a reland of d91679bf
> 
> Initializes the BackgroundCompileTasks's language_mode in the
> constructor (previously only initialized after successful parse) in case
> the parse failed. We still need to reset it after parse in case the
> language mode changed (because we encountered "use strict").
> 
> Original change's description:
> > [parser] Introduce UnoptimizedCompileFlags
> >
> > UnoptimizedCompileFlags defines the input flags shared between parse and
> > compile (currently parse-only). It is set initially with some values, and
> > is immutable after being passed to ParseInfo (ParseInfo still has getters
> > for the fields, but no setters).
> >
> > Since a few of the existing flags were output flags, ParseInfo now has a
> > new output_flags field, which will eventually migrate to a ParseOutputs
> > structure.
> >
> > Bug: v8:10314
> > Change-Id: If3890a5fad883bca80a97bf9dfe44d91797dc286
> > Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2096580
> > Commit-Queue: Leszek Swirski <leszeks@chromium.org>
> > Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> > Reviewed-by: Simon Zünd <szuend@chromium.org>
> > Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#66782}
> 
> TBR=ulan@chromium.org,szuend@chromium.org,rmcilroy@chromium.org
> 
> Bug: v8:10314
> Change-Id: Ieee0bbfade4fe0b56de03bff47a7364959608d6a
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2157367
> Reviewed-by: Leszek Swirski <leszeks@chromium.org>
> Commit-Queue: Leszek Swirski <leszeks@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#67265}

TBR=leszeks@chromium.org

Change-Id: I90ac035caa76d4c4baf5ce207247d1ce5169fb2f
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:10314
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2157370Reviewed-by: Sathya Gunasekaran  <gsathya@chromium.org>
Commit-Queue: Sathya Gunasekaran  <gsathya@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67266}

This is a reland of 0a59e0cb
which was a reland of 146f5375
which was a reland of d91679bf

Initializes the BackgroundCompileTasks's language_mode in the
constructor (previously only initialized after successful parse) in case
the parse failed. We still need to reset it after parse in case the
language mode changed (because we encountered "use strict").

Original change's description:
> [parser] Introduce UnoptimizedCompileFlags
>
> UnoptimizedCompileFlags defines the input flags shared between parse and
> compile (currently parse-only). It is set initially with some values, and
> is immutable after being passed to ParseInfo (ParseInfo still has getters
> for the fields, but no setters).
>
> Since a few of the existing flags were output flags, ParseInfo now has a
> new output_flags field, which will eventually migrate to a ParseOutputs
> structure.
>
> Bug: v8:10314
> Change-Id: If3890a5fad883bca80a97bf9dfe44d91797dc286
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2096580
> Commit-Queue: Leszek Swirski <leszeks@chromium.org>
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Reviewed-by: Simon Zünd <szuend@chromium.org>
> Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#66782}

TBR=ulan@chromium.org,szuend@chromium.org,rmcilroy@chromium.org

Bug: v8:10314
Change-Id: Ieee0bbfade4fe0b56de03bff47a7364959608d6a
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2157367Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67265}

Bug: chromium:1051186, chromium:1064326
Change-Id: Ied8d264ac3a40635f13ce09b2009135eaeb0118b
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2158485Reviewed-by: Dan Elphick <delphick@chromium.org>
Commit-Queue: Frank Tang <ftang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67264}

This reverts commit f442b03f.

Reason for reland: Wrongly reverted.

Original change's description:
> Revert "[turbofan] Fix bug in Number.Min/Max typings"
> 
> This reverts commit 4158af83.
> 
> Reason for revert: causing UBSAN failures:
> 
> https://ci.chromium.org/p/v8/builders/ci/V8%20Linux64%20UBSan/10729?
> 
> 
> Original change's description:
> > [turbofan] Fix bug in Number.Min/Max typings
> > 
> > They try to be very precise about when the result can be -0,
> > but do so incorrectly. I'm changing the code to just do the
> > simple thing instead. Let's see how that affects performance.
> > 
> > Bug: chromium:1072171
> > Change-Id: I9737a84aa19d06685af5b7bca541e348dc37cca8
> > Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2157028
> > Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
> > Commit-Queue: Georg Neis <neis@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#67246}
> 
> TBR=neis@chromium.org,tebbi@chromium.org
> 
> Change-Id: I0d9b312e27f5a8bbbebeccdc9819fa94f10af139
> No-Presubmit: true
> No-Tree-Checks: true
> No-Try: true
> Bug: chromium:1072171
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2157646
> Reviewed-by: Francis McCabe <fgm@chromium.org>
> Commit-Queue: Francis McCabe <fgm@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#67249}

TBR=neis@chromium.org,tebbi@chromium.org,fgm@chromium.org

Change-Id: Ida36ca584a5af5da887189328c8da195b26285d4
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: chromium:1072171
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2157368Reviewed-by: Georg Neis <neis@chromium.org>
Commit-Queue: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67263}

RegExpImpl::Compile does a number of transformations that require
directly manipulating the internal representation of the regexp. For
example, when matching a (non-sticky, non-anchored) regular
expression, the pattern must be wrapped in .* so that it can match
anywhere in the input.

In the interest of moving towards a cleaner division between irregexp
and the outside world, it makes sense to move this code into
RegExpCompiler.

R=jgruber@chromium.org

Bug: v8:10406
Change-Id: I6da251c91c0016914a51480f80bb46c337fd0b23
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2140246Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67262}

This is a reland of 52412058

Original change's description:
> [protectors] Add use counters to track invalidations
> 
> ... to make real world protector invalidations measurable.
> 
> Chromium CL: https://crrev.com/c/2149324
> 
> Drive-by: Add missing newline in protector tracing.
> Drive-by: Consistent naming for the regexp species protector.
> 
> Bug: v8:9496
> Change-Id: I3c7238aa8024e03ea9e89daf83345b8ec4f0d768
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2149428
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Commit-Queue: Jakob Gruber <jgruber@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#67149}

Bug: v8:9496
Change-Id: I3c97bfa747e8429569eaa09ea909de73fc377efa
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2151363Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67261}

LoadCurrentCharacterImpl is implemented once in each of the eight
regexp-macro-assembler-<arch>.cc files. Aside from small differences
in comment wording, those eight implementations are identical. The
architecture-specific code for LoadCurrentCharacter is all in
LoadCurrentCharacterUnchecked.

This patch hoists the definition of LoadCurrentCharacterImpl into
NativeRegExpMacroAssembler and turns LoadCurrentCharacterUnchecked
into a virtual function.

Note: The arm64 version of LoadCurrentCharacterImpl contained the
following six-year-old comment, which I don't think is worth
preserving:

// TODO(pielan): Make sure long strings are caught before this, and
// not just asserted in debug mode.

R=jgruber@chromium.org

Bug: v8:10406
Change-Id: Ic81283ad3b618d6b06f4206fb77d30de617dccb7
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2140003
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67260}

Port several CLs recorded in bug 9909.
We test this on 3A4000, and find many issues in MSA implement, but they are not related with this patch, will fix in another CL.
Looks like there is no 32-bit os for 3a4000, so we do not implements s128 for mips32.

Bug: v8:9909
Change-Id: Iad7569ebb92904bae66d420c8306cde24afb034a
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2147575
Commit-Queue: Yu Yin <xwafish@gmail.com>
Reviewed-by: Zhi An Ng <zhin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67259}

Bug: v8:9909
Change-Id: I11a07dcfe3362e8476ecf361f7de1c5047a34d7c
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2154330Reviewed-by: Zhi An Ng <zhin@chromium.org>
Commit-Queue: Jing Bao <jing.bao@intel.com>
Cr-Commit-Position: refs/heads/master@{#67258}

With https://crrev.com/c/2118476, we can decode multi byte opcodes. So
the module builder should be emitting the correct LEB encoded bytes for
SIMD opcodes.

This also fixes an error discovered by the fuzzer: I added f64x2.add to
the fuzzer, but that's actually a multi-byte opcode, so it resulted in
incorrect bytes generated. This should fix it.

Bug: chromium:1072090
Bug: v8:10258
Change-Id: I0b32ac27aa24d25ee8694dacb12d3d8339d9f839
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2158005Reviewed-by: Deepti Gandluri <gdeepti@chromium.org>
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67257}

This reverts commit 387d85ad.

Reason for revert: Broke ARM tree https://ci.chromium.org/p/v8/builders/ci/V8%20Arm%20-%20debug/13926?

Original change's description:
> [wasm-simd][liftoff][arm][arm64] Implement integer narrowing
> 
> Bug: v8:9909
> Change-Id: I0664df45fe399bfa018ff8bcacdbdae66944ed29
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2154834
> Reviewed-by: Clemens Backes <clemensb@chromium.org>
> Commit-Queue: Zhi An Ng <zhin@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#67254}

TBR=clemensb@chromium.org,zhin@chromium.org

Change-Id: I6e5cac9cf9e6070b4819edbde6cd2ada2d0b476a
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:9909
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2158010Reviewed-by: Zhi An Ng <zhin@chromium.org>
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67256}

Bug: v8:9909
Change-Id: Id7f3c438493d3a41eb36660c69bdea6bfa978c89
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2154766
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67255}

Bug: v8:9909
Change-Id: I0664df45fe399bfa018ff8bcacdbdae66944ed29
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2154834Reviewed-by: Clemens Backes <clemensb@chromium.org>
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67254}