This was disabled previously because the number of queues could not grow
above a predefined limit. Now that this is fixed, we can contribute to
compilation again instead of just waiting for recompilation to finish
(which might never happen if there are no background threads).

R=thibaudm@chromium.org

Change-Id: Ia0567bc8872246efb20ae8aaf96f9d689fca1c49
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2637863Reviewed-by: Thibaud Michaud <thibaudm@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72196}

This is a reland of cddaf66c

Original change's description:
> [compiler][wasm] Align Frame slots to value size
>
> - Adds an AlignedSlotAllocator class and tests, to unify slot
>   allocation. This attempts to use alignment holes for smaller
>   values.
> - Reworks Frame to use the new allocator for stack slots.
> - Reworks LinkageAllocator to use the new allocator for stack
>   slots and for ARMv7 FP register aliasing.
> - Fixes the RegisterAllocator to align spill slots.
> - Fixes InstructionSelector to align spill slots.
>
> Bug: v8:9198
>
> Change-Id: Ida148db428be89ef95de748ec5fc0e7b0358f523
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2512840
> Commit-Queue: Bill Budge <bbudge@chromium.org>
> Reviewed-by: Georg Neis <neis@chromium.org>
> Reviewed-by: Andreas Haas <ahaas@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#71644}

Bug: v8:9198
Change-Id: Ib91fa6746370c38496706341e12d05c7bf999389
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2633390
Commit-Queue: Bill Budge <bbudge@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72195}

The write barrier for storing a reference to an object requires the
destination offset as a parameter. The existing code only passed the
immediate offset, however, not the offset provided through a register.
With this CL, the correct offset is provided.

R=thibaudm@chromium.org

Bug: v8:7581
Change-Id: Ia2a1d90d822988a3ef0c27ce8227f28f0226c937
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2639766Reviewed-by: Thibaud Michaud <thibaudm@chromium.org>
Commit-Queue: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72194}

DevTools can't unambiguously determine whether code is JS or wasm.
This CL adds a string to the tracing output that will be 'JS', 'wasm' or
'other'.

Bug: chromium:1168052
Change-Id: Iaacb5ea9a83327e22d60bf6114f607e6fa5532ad
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2637859
Commit-Queue: Peter Marshall <petermarshall@chromium.org>
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72193}

While clang++ doesn't mind, g++ complains about apostrophes in #error
messages as they appear to be unterminated single-quoted literals. So
add surrounding double-quotes.

Bug: v8:11292
Change-Id: Ib263cb20c73650348599992186a0e7de11b1b306
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2639763
Auto-Submit: Dan Elphick <delphick@chromium.org>
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72192}

The inlining of JS-to-Wasm wrappers can fail inside try/catch because
the IR built by WasmWrapperGraphBuilder::BuildJSToWasmWrapper does not
always set the correct control outputs in the call node.
This patch disables inlining inside try/catch to work around this issue.

Bug: chromium:1168386
Change-Id: I1b43bdb044b38d95c2d309290e228a86ba1513a3
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2639927Reviewed-by: Andreas Haas <ahaas@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Commit-Queue: Paolo Severini <paolosev@microsoft.com>
Cr-Commit-Position: refs/heads/master@{#72191}

The bytecode offset (previously 'bailout id') was referred to as 'ast
id', 'node id', 'bailout id' in different spots. And 'bailout id' was
used to refer to deoptimization exits. This CL makes used terms more
consistent.

Bug: v8:11332
Change-Id: I2b34c7d4ebf465939e18fdfba675d83852f2430a
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2639756
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Nico Hartmann <nicohartmann@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72190}

This reflects the actual contents of the type, which is an offset into
the bytecode (or certain marker values). Historically, in the days of
FCG the bailout id used to refer to node ids - this is why certain
tracing output still calls the bailout id 'node id' and 'ast id'.
These spots will be fixed in a follow-up CL.

This change is mechanical:

 git grep -l BailoutId | while read f; do \
  sed -i 's/BailoutId/BytecodeOffset/g' $f; done

With a manual component of updating the DeoptimizationData method
name from 'BytecodeOffset' to 'GetBytecodeOffset'.

Bug: v8:11332
Change-Id: I956b947a480bf52263159c0eb1e895360bcbe6d2
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2639754
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Nico Hartmann <nicohartmann@chromium.org>
Reviewed-by: Mythri Alle <mythria@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72189}

Change-Id: Ia05a7bfcb56984658d4448c7d52150dfbadd0660
Bug: v8:11312
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2639953Reviewed-by: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Commit-Queue: Victor Gomes <victorgomes@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72188}

This change adds Torque field definitions for ScopeInfo and begins to
use the Torque-generated accessors in some places. It does not change
the in-memory layout of ScopeInfo.

Torque compiler changes:

- Fix an issue where the parser created constexpr types for classes
  based on the class name rather than the `generates` clause. This meant
  that generated accessors referred to the imaginary type HashTable
  rather than the real C++ type FixedArray.
- Don't pass Isolate* through the generated runtime functions that
  implement Torque macros. Maybe we'll need it eventually, but we don't
  right now and it complicates a lot of things.
- Don't emit `kSomeFieldOffset` if some_field has an unknown offset.
  Instead, emit a member function `SomeFieldOffset()` which fetches the
  slice for some_field and returns its offset.
- Emit an `AllocatedSize()` member function for classes which have
  complex length expressions. It fetches the slice for the last field
  and performs the multiply&add to compute the total object size.
- Emit field accessors for fields with complex length expressions, using
  the new offset functions.
- Fix a few minor bugs where Torque can write uncompilable code.

With this change, most code still treats ScopeInfo like a FixedArray, so
I would like to follow up with some additional changes:

1. Generate a GC visitor for ScopeInfo and use it
2. Generate accessors for struct-typed fields (indexed or otherwise),
   and use them
3. Get rid of the FixedArray-style get and set accessors; use
   TaggedField::load and similar instead
4. Inherit from HeapObject rather than FixedArrayBase to remove the
   unnecessary `length` field

After that, there will only be one ugly part left: initialization. I
think it's possible to generate a factory function that takes a bunch of
iterator parameters and returns a fully-formed, verifiably correct
ScopeInfo instance, but doing so is more complicated than the four
mostly-mechanical changes listed above.

Bug: v8:7793
Change-Id: I55fcfe9189e4d1613c68d49e378da5dc02597b36
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2357758Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Peter Marshall <petermarshall@chromium.org>
Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Commit-Queue: Seth Brenith <seth.brenith@microsoft.com>
Cr-Commit-Position: refs/heads/master@{#72187}

Doing a function call into the logger to decide whether logging is
enabled or not is more costly than necessary.

This CL changes logging to take FLAG_log as main signal whether logging
could be active. If FLAG_log == false, logging cannot be active. In
that case we always call into the logger and perform detailed checks
there.

This CL changes flag-definitions to set FLAG_log if they need logging.

Change-Id: Ia51ed9fb7128451bf1dcf345fab257547aab4a47
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2602461Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Camillo Bruni <cbruni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72186}

Without the adaptor frame, this is dead code.

Change-Id: Ica1ee102fcc068a58c5dcbca6122921cd1b5550a
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2639760Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Victor Gomes <victorgomes@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72185}

Bug: chromium:1064551
Change-Id: I81935d9bfe7b779f6f33ae8afa54f5b86c6bd74e
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2637224Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Liviu Rau <liviurau@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72184}

This is a reland of 8703c38d

The reland marks the new test as slow, skips all variants, and
skips all non-release modes.

Original change's description:
> [compiler] Emit a function-entry stack check on OSR-entry
>
> This CL extends the smarter function-entry stack check logic (see
> v8:9534) to OSR'd code. These smarter stack checks prevent
> overflowing the stack during deoptimization.
>
> The challenge for both function-entry (FE) and OSR-entry (OE) stack
> checks is that there is no dedicated physical StackCheck to
> deoptimize into. For more context: the physical StackCheck bytecode
> was removed in crrev.com/c/1914218.
>
> FE stack checks solve this by using a marker bailout id to signify
> a deopt bytecode offset before the first bytecode.
>
> In this CL, OE stack checks take a similar approach by using the
> OSR'd loop's JumpLoop bytecode, which is conceptually immediately
> before the OSR'd loop header.
>
> When a stack overflow at an OE stack check occurs: %StackGuard
> may cause a lazy deopt on return to the optimized OSR code,
> causing re-execution of the JumpLoop handler in the
> InterpreterEnterBytecodeAdvance builtin, ultimately continuing
> execution the interpreter at the first bytecode of the OSR'd loop
> header.
>
> Bug: chromium:1034322, v8:9534
> Change-Id: I1ae88a08702cde9a5eb84a451a9f1acc41204d5c
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2625872
> Auto-Submit: Jakob Gruber <jgruber@chromium.org>
> Reviewed-by: Santiago Aboy Solanes <solanes@chromium.org>
> Reviewed-by: Georg Neis <neis@chromium.org>
> Commit-Queue: Jakob Gruber <jgruber@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#72153}

Tbr: neis@chromium.org, solanes@chromium.org
Bug: chromium:1034322
Bug: v8:9534
Change-Id: I28a23d0cc4b14d59c3d4a5dbadd5dab3ac31d442
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2639753Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72183}

This reverts commit a8451683.

Reason for revert: Breaks TSAN builds and closes the tree, see https://bugs.chromium.org/p/v8/issues/detail?id=11333

Original change's description:
> Update V8 DEPS.
>
> Rolling v8/build: https://chromium.googlesource.com/chromium/src/build/+log/43dd249..781f002
>
> Rolling v8/third_party/catapult: https://chromium.googlesource.com/catapult/+log/cf567b6..d168442
>
> Rolling v8/third_party/depot_tools: https://chromium.googlesource.com/chromium/tools/depot_tools/+log/dabd965..c3c15a1
>
> Rolling v8/tools/clang: https://chromium.googlesource.com/chromium/src/tools/clang/+log/ba4ee03..683dad6
>
> TBR=machenbach@chromium.org,tmrts@chromium.org,v8-waterfall-sheriff@grotations.appspotmail.com
>
> Change-Id: I8c66185943738477e595672ba7d9efa243d062d3
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2638915
> Reviewed-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@{#72181}

TBR=machenbach@chromium.org,v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com,tmrts@chromium.org,v8-waterfall-sheriff@grotations.appspotmail.com

Change-Id: If5905806b9cd0c8e033df8554edd9e01bca29e30
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2639755Reviewed-by: Maya Lekova <mslekova@chromium.org>
Commit-Queue: Maya Lekova <mslekova@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72182}

Rolling v8/build: https://chromium.googlesource.com/chromium/src/build/+log/43dd249..781f002

Rolling v8/third_party/catapult: https://chromium.googlesource.com/catapult/+log/cf567b6..d168442

Rolling v8/third_party/depot_tools: https://chromium.googlesource.com/chromium/tools/depot_tools/+log/dabd965..c3c15a1

Rolling v8/tools/clang: https://chromium.googlesource.com/chromium/src/tools/clang/+log/ba4ee03..683dad6

TBR=machenbach@chromium.org,tmrts@chromium.org,v8-waterfall-sheriff@grotations.appspotmail.com

Change-Id: I8c66185943738477e595672ba7d9efa243d062d3
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2638915Reviewed-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@{#72181}

The codegen for q15 rounding mul and dot incorrectly assumes that the
second operand is always a register.

For dot, we change the codegen to accept an Operand.

For q15, we change the instruction-selector to always use register.

Bug: v8:10971,v8:10993
Change-Id: I30a421de47ba61693ca73e616bcbc27ab01ac7bc
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2626712Reviewed-by: Bill Budge <bbudge@chromium.org>
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72180}

Prototype load lane instructions on ia32 Liftoff.

We generalize the pinsr* macro-assembler functions to take an extra
input, following the 3 operand + 1 imm form of the AVX instructions.

Bug: v8:10975
Change-Id: I3fa10d149b011b62edd58372148446b663f3dc3c
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2619417Reviewed-by: Clemens Backes <clemensb@chromium.org>
Reviewed-by: Bill Budge <bbudge@chromium.org>
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72179}

Bug: v8:10971
Change-Id: Ie2409df6909d3be40f998445ae9c9b35c96ef3a8
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2632012Reviewed-by: Deepti Gandluri <gdeepti@chromium.org>
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72178}

This instruction has been merged into the proposal:
https://github.com/WebAssembly/simd/pull/365

Bug: v8:10971
Change-Id: I4dcad343a99271e1af4a48497e9f4ecc20785dcf
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2632011Reviewed-by: Deepti Gandluri <gdeepti@chromium.org>
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72177}

Change-Id: I586f3331fc8f468f799915e02e5863310e98937c
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2636843Reviewed-by: Junliang Yan <junyan@redhat.com>
Commit-Queue: Milad Fa <mfarazma@redhat.com>
Cr-Commit-Position: refs/heads/master@{#72176}

Instead, use Is<NativeContext> then UnsafeCast.

Bug: v8:9679
Change-Id: Id87a10fa66ff1c1e0ca0099b1938c72da2437832
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2631554
Commit-Queue: Z Nguyen-Huu <duongn@microsoft.com>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72175}

Code sequence from https://github.com/WebAssembly/simd/pull/379.

Bug: v8:11002
Change-Id: I47c1090d792f8cbb9d7846ace9a4f996d0c460b1
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2626717Reviewed-by: Deepti Gandluri <gdeepti@chromium.org>
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72174}

Port 624030e9

Original Commit Message:

    This will allow us optimize the protector cell checks in the fast path
    from checking against the function object in every context to just
    doing a range check against the instance type.

    This patch adds new instance types for constructor functions that
    require such protector cell checks.

R=gsathya@chromium.org, joransiu@ca.ibm.com, junyan@redhat.com, midawson@redhat.com
BUG=
LOG=N

Change-Id: If5918721117e87579a3c6a2a4ed6245bd033a88e
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2636840Reviewed-by: Junliang Yan <junyan@redhat.com>
Reviewed-by: Milad Fa <mfarazma@redhat.com>
Commit-Queue: Milad Fa <mfarazma@redhat.com>
Cr-Commit-Position: refs/heads/master@{#72173}

Bug: v8:7790
Change-Id: I7900d041ff1331991d14e2766a6760b69f37622e
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2637230Reviewed-by: Georg Neis <neis@chromium.org>
Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72172}

This would be useful for ForInPrepare. Syntax is unchanged; Torque
should now do the right thing for builtins that return a two-element
struct. More elements than that is still not supported.

Bug: v8:7793
Change-Id: Ic315699402203aba07e906ff6e029834ec0061c6
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2596498Reviewed-by: Nico Hartmann <nicohartmann@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Seth Brenith <seth.brenith@microsoft.com>
Cr-Commit-Position: refs/heads/master@{#72171}

This prototypes i32x4.widen_i8x16_s and i32x4.widen_i8x16_u for the
interpreter.

This is the first instruction of its kind, a post-mvp, unary operation
that takes one immediate. Which is why there are more changes to the
decoder than usual.

Bug: v8:11297
Change-Id: Ib5c58965e0cba8d7a395b0dc57673110bc60e87c
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2617385Reviewed-by: Deepti Gandluri <gdeepti@chromium.org>
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72170}

1) Computed property keys (esp functions in them) shouldn't be inside
the object literal scope.

2) I was using an imprecise "maybe uses super" and storing it to
preparse data. This won't fly, since it pollutes sister scopes and
leads to confusion wrt whether an object literal needs a home object
or not. Made it precise (mostly cancelling changes in the original CL).

3) PreParser::NewSuperPropertyReference was creating a VariableProxy for
this_function (which made it used) -> inconsistent scopes between
parsing and preparsing.

4) MultipleEntryBlockContextScope was messing up the accumulator

Original: https://chromium-review.googlesource.com/c/v8/v8/+/2563275

This saves memory (the home object doesn't need to be stored for each
method, but only once per class) and hopefully makes the home object
a constant in the optimized code.

Detailed documentation of the changes:
https://docs.google.com/document/d/1ZVXcoQdf9IdMsnRI9iyUjyq9NDoEyx9nA3XqMgwflMs/edit?usp=sharing

Bug: v8:9237, chromium:1167918, chromium:1167981, chromium:1167988, chromium:1168055
Change-Id: I4f53f18cc18762c33e53d8c802909b42f1c33538
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2637220Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Marja Hölttä <marja@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72169}

Bug: chromium:1166989
Change-Id: I6eca7745ee4457d86ecda65a3972011899bac9c2
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2637219
Auto-Submit: Liviu Rau <liviurau@chromium.org>
Commit-Queue: Liviu Rau <liviurau@chromium.org>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72168}

`last` indicates that it's the last element of the list but in reality
this supposed to indicate the previous entry in the list. Rename this
to something more clearer.

Change-Id: I26c9a1fca02cf6b10d0447768da694d590a43932
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2637229Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Commit-Queue: Sathya Gunasekaran  <gsathya@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72167}

Moves the serialization of the initial set of maps read from the native
context from the forground serialization phase to a new background
serialization phase.

BUG=v8:7790,v8:9684

Change-Id: Id408e5c3096e832cf30106eb8fb7d65518432e06
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2613028
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Reviewed-by: Nico Hartmann <nicohartmann@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72166}

On arm64, Windows Performance Recorder gets confused by the fact that fp
in Builtins_JSEntry doesn't point to the saved {fp, lr} pair for the
caller frame. The expected usage of fp is documented in [1]:

  The frame pointer (x29) is required for compatibility with fast stack
  walking used by ETW and other services. It must point to the previous
  {x29, x30} pair on the stack.

In slightly more detail, the Windows function RtlWalkFrameChain is
responsible for generating stack traces during profiling with Windows
Performance Recorder, and that function relies on the rule quoted above.
Notably, it does not make any effort to read the unwinding data that one
could obtain with RtlLookupFunctionEntry. Stack walks using that data,
such as those performed by WinDbg and the cctest StackUnwindingWin64,
work fine.

It would be convenient if we could use fp in a more standard way during
JSEntry so that Windows profiling tools work correctly. (We can also
reduce JSEntry by two instructions in doing so.)

Both arm and arm64 currently put a -1 value on the stack at the location
that fp points to. This could prevent accidental access during the
epilog of JSEntry, where fp might be zero. However, we believe that this
protection is no longer necessary, and any bug that causes a read from
fp during the end of JSEntry would cause various CQ failures.

[1] https://docs.microsoft.com/en-us/cpp/build/arm64-windows-abi-conventions?view=msvc-160

Change-Id: Iece5666129b9188fc4c12007809b50f046f4044f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2607636
Commit-Queue: Seth Brenith <seth.brenith@microsoft.com>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72165}

The test was explicitly tiering up or down a module, without respecting
other isolates. Thus it was failing in multi-isolate mode.
This CL removes two runtime functions which do not make sense in a
multi-isolate setting (and were only used in this one test), and
replaces them with runtime functions that mimic what enabling/disabling
the debugger domain does: As long as there is at least one isolate which
needs modules to be tiered down, we keep them tiered down.

R=thibaudm@chromium.org

Bug: v8:10359, v8:10099
Change-Id: Ia85f4ea29ba6a6bb54aca54a48fadd351121d3eb
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2637231Reviewed-by: Thibaud Michaud <thibaudm@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72164}

The engine can be retrieved from the NativeModule, hence avoid passing
it explicitly.

R=ahaas@chromium.org

Change-Id: I38f9bdb9624006da8311e57c3e53327654b6e85a
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2637855Reviewed-by: Andreas Haas <ahaas@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72163}

Change-Id: Ifad7bbafc8b7c7ff8cf9140b9227cb9c67370fcf
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2637856
Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
Auto-Submit: Georg Neis <neis@chromium.org>
Reviewed-by: Santiago Aboy Solanes <solanes@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72162}

The helper encapsulates the `x - x` pattern to silence NaN `x`.

Bug: v8:7519
Change-Id: Ia633272d7b7cc350c7e4db07e271e0192c68019f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2637232
Auto-Submit: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Nico Hartmann <nicohartmann@chromium.org>
Reviewed-by: Nico Hartmann <nicohartmann@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72161}

Change-Id: I3803e3f7916827b3b9853c8c3a3ce6806cc2daac
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2636054
Commit-Queue: Junliang Yan <junyan@redhat.com>
Reviewed-by: Milad Fa <mfarazma@redhat.com>
Cr-Commit-Position: refs/heads/master@{#72160}

This was originally proposed by yangguo@ on the original CL that
introduced this, but back then it looked easier to put the map cache
onto the global object than on the native context. However it turns out
that this is indeed quite strange and also not necessarily supported (we
got crashes from the wild indicating that the `Object::GetProperty()`
might fail on the global object). So this CL simplifies the original
design and just puts the map cache onto the native context like with do
with other context specific maps.

Fixed: chromium:1167399
Bug: chromium:1127914, chromium:1159402, chromium:1071432, chromium:1164241
Change-Id: Ie16f892dd19b55b4c49e9d4829cab3c24ae64ad3
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2637226
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Auto-Submit: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72159}

This reverts commit 8703c38d.

Reason for revert: New test is timing out on gc-stress (e.g. https://ci.chromium.org/ui/p/v8/builders/ci/V8%20Linux%20-%20gc%20stress/31726/overview)

Original change's description:
> [compiler] Emit a function-entry stack check on OSR-entry
>
> This CL extends the smarter function-entry stack check logic (see
> v8:9534) to OSR'd code. These smarter stack checks prevent
> overflowing the stack during deoptimization.
>
> The challenge for both function-entry (FE) and OSR-entry (OE) stack
> checks is that there is no dedicated physical StackCheck to
> deoptimize into. For more context: the physical StackCheck bytecode
> was removed in crrev.com/c/1914218.
>
> FE stack checks solve this by using a marker bailout id to signify
> a deopt bytecode offset before the first bytecode.
>
> In this CL, OE stack checks take a similar approach by using the
> OSR'd loop's JumpLoop bytecode, which is conceptually immediately
> before the OSR'd loop header.
>
> When a stack overflow at an OE stack check occurs: %StackGuard
> may cause a lazy deopt on return to the optimized OSR code,
> causing re-execution of the JumpLoop handler in the
> InterpreterEnterBytecodeAdvance builtin, ultimately continuing
> execution the interpreter at the first bytecode of the OSR'd loop
> header.
>
> Bug: chromium:1034322, v8:9534
> Change-Id: I1ae88a08702cde9a5eb84a451a9f1acc41204d5c
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2625872
> Auto-Submit: Jakob Gruber <jgruber@chromium.org>
> Reviewed-by: Santiago Aboy Solanes <solanes@chromium.org>
> Reviewed-by: Georg Neis <neis@chromium.org>
> Commit-Queue: Jakob Gruber <jgruber@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#72153}

TBR=neis@chromium.org,jgruber@chromium.org,solanes@chromium.org

Change-Id: Ie72f2e2927ffa83d595aad0d88c606d422f953a2
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: chromium:1034322
Bug: v8:9534
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2637858Reviewed-by: Clemens Backes <clemensb@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72158}

Change-Id: I42ff5501bec10ef5230ea06d5feb9adc5be0d875
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2633731Reviewed-by: Milad Fa <mfarazma@redhat.com>
Commit-Queue: Junliang Yan <junyan@redhat.com>
Cr-Commit-Position: refs/heads/master@{#72157}