Change-Id: I4f7c80f89ad4d023f96a9113ebb6628df44fb61c
Reviewed-on: https://chromium-review.googlesource.com/c/1469325Reviewed-by: Peter Marshall <petermarshall@chromium.org>
Commit-Queue: Alexei Filippov <alph@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59607}

This is a reland of cee2f772

Original change's description:
> [build] disable C++ optimization for mksnapshot code.
> 
> By disabling C++ optimizations for code that's only run in mksnapshot,
> that is, CSA and Torque-generated code, we can save compile time.
> I observed up to 2x improvements of compile time for some files,
> while the mksnapshot time did not increase significantly.
> 
> Bug: v8:7629
> Change-Id: I96be2966611b2471b68023e0dd9e351d94f0013c
> Reviewed-on: https://chromium-review.googlesource.com/c/1460941
> Reviewed-by: Yang Guo <yangguo@chromium.org>
> Reviewed-by: Sigurd Schneider <sigurds@chromium.org>
> Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#59585}

Bug: v8:7629
Change-Id: I8330f93173ab3d7b400e15ea4935bbe8256b250f
Reviewed-on: https://chromium-review.googlesource.com/c/1473292
Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
Commit-Queue: Sigurd Schneider <sigurds@chromium.org>
Reviewed-by: Sigurd Schneider <sigurds@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59606}

This removes another two macros and introduces a templatized function
instead.
Note that there is only one instantiation per input length, not per
input.

R=titzer@chromium.org

Bug: v8:8562
Change-Id: I47ad274e68d26b962cbd582e90995d30b1d09d39
Reviewed-on: https://chromium-review.googlesource.com/c/1460938
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59605}

In the wasm streaming decoder error position test, do also check the
error messages generated. This revealed messages that were not quite
fitting and some that were formatted differently than the majority.

R=ahaas@chromium.org

Bug: v8:8814
Change-Id: If157f1083a104413bf14797ac56e756baac98c17
Reviewed-on: https://chromium-review.googlesource.com/c/1463780
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59604}

Change-Id: Ic60f74a60480ea4a74e039c5c87e8c1995e60453
Bug: v8:8834
Reviewed-on: https://chromium-review.googlesource.com/c/1473032Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Sigurd Schneider <sigurds@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59603}

Bug: v8:8477, v8:8834
Change-Id: I9213cca077a2758b87a6cb95bcb01d0186c32098
Reviewed-on: https://chromium-review.googlesource.com/c/1472633Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59602}

R=tebbi@chromium.org
BUG=chromium:931536

Change-Id: I3a6dbabec7a84f55d6aa85934dca37af55390552
Reviewed-on: https://chromium-review.googlesource.com/c/1473034Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59601}

This is already blocked when PRIVATE_NAME is parsed anyway, and we simply need
to make sure that we don't continue. So marking the prop_info->kind as kNotSet
will do what you want via the unexpected path rather than through the main hot
path.

Bug: v8:8808
Change-Id: I93beb80a89cf764cd79d6c3ec3a5fc763a98c4d6
Reviewed-on: https://chromium-review.googlesource.com/c/1472635Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59600}

HeapNumbers and MutableHeapNumber requires alignment for their double
value field but for now this field can be misaligned on 32-bit platforms.

According to code in Heap::GetFillToAlign() function, kDoubleUnaligned
doesn't actually mean "unaligned" but "aligned to half of double".

This CL fixes this misalignment.

Change-Id: I9b9c58d580bb287e7dad44bc96cd6b4593707b5e
Reviewed-on: https://chromium-review.googlesource.com/c/1470113
Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59599}

When calling into API callbacks from TurboFan optimized, we can
currently only take a fast-path when TurboFan is able to find some
information about the receiver in the graph, or when the API callback
specifies that it neither requires an access check (aka "accepts any
receiver") nor an interface check (aka "compatible receiver check").

This change introduces a new CallFunctionTemplate builtin that sits
in front of the CallApiCallback builtin and does both the access as well
as the interface check as necessary (and raises appropriate exceptions).
This way TurboFan can still call into the API callback via the fast-path
even without ahead knowledge about the receiver, which is significantly
faster than the generic call machinery for API callbacks.

On the test case from the Angular team[1], the interesting metrics
improve from

  DOM_mono: 0.273 ms
  DOM_mega: 0.571 ms
  DOM_call: 0.649 ms

to

  DOM_mono: 0.264 ms
  DOM_mega: 0.572 ms
  DOM_call: 0.368 ms

so the DOM_call is only about **1.4 times slower** than the DOM_mono and
about **1.5 times faster** than the DOM_mega case (compared to **2.4
times slower**). Execution time in the DOM_call was reduced by around
**~45%**.

Currently this new code path is limited to TurboFan optimized code, but
the idea is to eventually migrate the API calls from baseline to also
use the new CSA functionality, but there are lot's of subleties to take
into account, so starting with small changes to get coverage for the
basic building blocks.

[1]: https://mhevery.github.io/perf-tests/DOM-megamorphic.html

Bug: v8:8820
Change-Id: Ie1029cf182ce05a6e519fd9a9d4fa825db8adb4c
Cq-Include-Trybots: luci.chromium.try:linux-blink-rel
Reviewed-on: https://chromium-review.googlesource.com/c/1470129
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59598}

This is a reland of 74951850

Original change's description:
> [wasm] Fix two jump table offset parameters.
> 
> R=jgruber@chromium.org
> 
> Change-Id: I5b40819b1a746f16b7b18aac1bba65d83a7e3483
> Reviewed-on: https://chromium-review.googlesource.com/c/1470127
> Reviewed-by: Jakob Gruber <jgruber@chromium.org>
> Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#59560}

Change-Id: I70b814f81bfd0c13e09a2641871da2d4ec5a308d
Reviewed-on: https://chromium-review.googlesource.com/c/1470111Reviewed-by: Maya Lekova <mslekova@chromium.org>
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59597}

The builders were originally allowed higher cycle time, as fast responses
weren't necessary. They should, however, never fail due to expiring tasks.

This has happened more often lately, hence they should run with normal
CI priority. The impact is very small as they run very infrequently.

NOTRY=true

Bug: chromium:930255
Change-Id: Id9d4eb70322862cf98b9ae4e313e5c0b002b5bd1
Reviewed-on: https://chromium-review.googlesource.com/c/1466303
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Reviewed-by: Sergiy Belozorov <sergiyb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59596}

If enable_omit_source_positions is true (defaults to false), source
position tables are not generated when compiling bytecode. They will
then be regenerated when exceptions are thrown.

This adds a new function Compiler::CollectSourcePositions which given a
SharedFunctionInfo with bytecode but no source position table re-parses
and regenerates the bytecode but this time with source positions
collection enabled. Note this will reparse all inner functions that
have previously been compiled since the preparse data is no longer
available.

With the flag enabled there still 18 test failures mostly related to
debugging.

v8: 8510
Change-Id: I46dff9818d8a89c901ba8ae8df94dcaca83aa658
Reviewed-on: https://chromium-review.googlesource.com/c/1385165
Commit-Queue: Dan Elphick <delphick@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59595}

R=leszeks@chromium.org

Change-Id: Ib66b36884be7dd1283eb0375cfaf94a5b503f162
Reviewed-on: https://chromium-review.googlesource.com/c/1470110Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Yang Guo <yangguo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59594}

Change-Id: I616841c626fc95a6015014e308cbd653e95ede19
Reviewed-on: https://chromium-review.googlesource.com/c/1472671Reviewed-by: Maya Lekova <mslekova@chromium.org>
Commit-Queue: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59593}

... such that the feedback maps can evenentually be processed in the
serialization phase.

Bug: v8:7790
Change-Id: Ic033e88646a1b161710b1ca2028ef10f49d23cfd
Reviewed-on: https://chromium-review.googlesource.com/c/1472293Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59592}

Similar to x64's CL (https://chromium-review.googlesource.com/c/v8/v8/+/1459638)

Bug: v8:7703
Change-Id: I4b4e06ccdb9f428559dfb6b74e8ac149f955745c
Reviewed-on: https://chromium-review.googlesource.com/c/1467181Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59591}

The megamorphic case in the KeyedStoreIC doesn't use/update any feedback.
We could use this path to fast path some of the keyed stores instead of
misssing to the runtime when the feedback vector is not available. This
cl, moves the check for feedback vector from the bytecode handler to the
KeyedStoreIC and calls the KeyedStoreIC_Megamorphic builtin when there is
no valid feedback vector. This will help improve the performance of no
feedback/jitless case.

Bug: v8:8293
Change-Id: I71c128b355d47ac20e50fc836f4bc2cf0aab1154
Reviewed-on: https://chromium-review.googlesource.com/c/1460946
Commit-Queue: Mythri Alle <mythria@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59590}

It shipped in Chrome 70.

Bug: v8:7807, v8:8562
Change-Id: I5c5a9fc23656018ee6e9115af7a0c779230e681b
Reviewed-on: https://chromium-review.googlesource.com/c/1450787
Commit-Queue: Mathias Bynens <mathias@chromium.org>
Reviewed-by: Sathya Gunasekaran <gsathya@chromium.org>
Reviewed-by: Adam Klein <adamk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59589}

Class member initializer functions do not support lazy compilation, so
change FunctionLiteral::AllowsLazyCompilation to return false for them.

Change-Id: I38434f3a7e8c88af3f407cf19308fc3862ec4403
Reviewed-on: https://chromium-review.googlesource.com/c/1470103Reviewed-by: Yang Guo <yangguo@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Commit-Queue: Dan Elphick <delphick@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59588}

Bug: chromium:930304
Change-Id: I7793f83b3f3e9aeaa3ecf114c6064773257e90e8
Reviewed-on: https://chromium-review.googlesource.com/c/1461167Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Commit-Queue: Frank Tang <ftang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59587}

This reverts commit cee2f772.

Reason for revert: Breaks sanitizer builds: https://ci.chromium.org/p/v8/builders/luci.v8.ci/V8%20Linux64%20UBSan/4682

Original change's description:
> [build] disable C++ optimization for mksnapshot code.
> 
> By disabling C++ optimizations for code that's only run in mksnapshot,
> that is, CSA and Torque-generated code, we can save compile time.
> I observed up to 2x improvements of compile time for some files,
> while the mksnapshot time did not increase significantly.
> 
> Bug: v8:7629
> Change-Id: I96be2966611b2471b68023e0dd9e351d94f0013c
> Reviewed-on: https://chromium-review.googlesource.com/c/1460941
> Reviewed-by: Yang Guo <yangguo@chromium.org>
> Reviewed-by: Sigurd Schneider <sigurds@chromium.org>
> Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#59585}

TBR=yangguo@chromium.org,sigurds@chromium.org,tebbi@chromium.org

Change-Id: I50da40da167f49a14e3a8994377c4f9dafdfe2ab
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:7629
Reviewed-on: https://chromium-review.googlesource.com/c/1472630Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59586}

By disabling C++ optimizations for code that's only run in mksnapshot,
that is, CSA and Torque-generated code, we can save compile time.
I observed up to 2x improvements of compile time for some files,
while the mksnapshot time did not increase significantly.

Bug: v8:7629
Change-Id: I96be2966611b2471b68023e0dd9e351d94f0013c
Reviewed-on: https://chromium-review.googlesource.com/c/1460941Reviewed-by: Yang Guo <yangguo@chromium.org>
Reviewed-by: Sigurd Schneider <sigurds@chromium.org>
Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59585}

has_prototype_slot on Context::FunctionMapIndex() is unused in its
implementation, and all callers passes just true.
Whether the function has prototype or not is determined by FunctionKind
instead.

Change-Id: I598515b25267dd3470cccbf3236b5e64c6959d00
Reviewed-on: https://chromium-review.googlesource.com/c/1469542Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Taiju Tsuiki <tzik@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59584}

... to ec358ccfd63a2a657c147329c7793d217e278a58.

This adds support for CBOR <-> Value.

v8 changes:
- Add StringUTF8Adapter (from Pavel's change)
- Add Binary::fromSpan (needed for the cbor->BinaryValue conversion).

Change-Id: I09746dc361df0b150b23697a20b287613558c003
Reviewed-on: https://chromium-review.googlesource.com/c/1470955
Commit-Queue: Pavel Feldman <pfeldman@chromium.org>
Reviewed-by: Pavel Feldman <pfeldman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59583}

Focuses on decoder implementation and unittests of decoding return call instructions

Bug: v8:7431
Change-Id: Ib1351bb26f8bac0a766d633486492fcd8ead627b
Reviewed-on: https://chromium-review.googlesource.com/c/1455476
Commit-Queue: Francis McCabe <fgm@chromium.org>
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59582}

This is part 1 of 2 of clean up. C++ change in Part 2 next.

Bug: v8:8705
Change-Id: Ibf4425c141391581b963f4775286b65b652452e2
Reviewed-on: https://chromium-review.googlesource.com/c/1461172Reviewed-by: Sathya Gunasekaran <gsathya@chromium.org>
Commit-Queue: Frank Tang <ftang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59581}

The uninitialized case in the StoreIC doesn't use any feedback.
We could use this path to fast path some of the named stores instead of
missing to the runtime when the feedback vector is not available.

Bug: v8:8293
Change-Id: Ib3c4f843b24a377708f8db18fae10983e5633484
Reviewed-on: https://chromium-review.googlesource.com/c/1463781
Commit-Queue: Mythri Alle <mythria@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59580}

Header generating action needs to be in public_deps if generated header is included from header file in the targets depending on the action target.

See below reference for more details.
https://gn.googlesource.com/gn/+/master/docs/reference.md#var_public_deps

Bug: chromium:931596
Change-Id: I198d9e09b8585b213ec4b375f10aecc6268f3bdd
Reviewed-on: https://chromium-review.googlesource.com/c/1469545Reviewed-by: Yang Guo <yangguo@chromium.org>
Commit-Queue: Takuto Ikuta <tikuta@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59579}

I had forgotten to remove this in
https://chromium-review.googlesource.com/c/v8/v8/+/1458243

Change-Id: Id0da5f87f782e854b204f400173aa2bbecb4c43c
Reviewed-on: https://chromium-review.googlesource.com/c/1470133Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59578}

Bug: v8:8562
Change-Id: I7f65b4cd92bb08434afe3a18512223adaf47feec
Reviewed-on: https://chromium-review.googlesource.com/c/1470112
Commit-Queue: Maciej Goszczycki <goszczycki@google.com>
Reviewed-by: Dan Elphick <delphick@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59577}

This API has existed for two and a half years now, with no
API changes over the last year, and is widely used in production,
code so it makes sense to consider it stable.

Change-Id: I10e38c37fb8c13e22124ef0985f4b0bd8d4615fd
Reviewed-on: https://chromium-review.googlesource.com/c/1461999Reviewed-by: Yang Guo <yangguo@chromium.org>
Commit-Queue: Yang Guo <yangguo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59576}

This switches from copying entire runtime stubs into each module to only
having small jump table slots in each module that act as a trampoline to
the actual embedded builtin representing the runtime stub. This reduces
the memory footprint of modules.

R=clemensh@chromium.org

Change-Id: I3de528f7ebcc104f114ec32914d2b86e810d10d6
Reviewed-on: https://chromium-review.googlesource.com/c/1460474
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59575}

Bug: chromium:926235
Change-Id: I7af37f574c03439da34afc86cc8e6f49c3781579
Reviewed-on: https://chromium-review.googlesource.com/c/1470810
Commit-Queue: Junliang Yan <jyan@ca.ibm.com>
Reviewed-by: Milad Farazmand <miladfar@ca.ibm.com>
Cr-Commit-Position: refs/heads/master@{#59574}

Bug: chromium:852420
Change-Id: Ic34b996460b9ad2124f4bdb18afdcc83f2453e6a
Reviewed-on: https://chromium-review.googlesource.com/c/1470109Reviewed-by: Sigurd Schneider <sigurds@chromium.org>
Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59573}

TBR=sergiyb@chromium.org

Bug: v8:8840
Change-Id: I04c2e6a1703764416cbb9987de262fe4d2b86b14
Reviewed-on: https://chromium-review.googlesource.com/c/1470105Reviewed-by: Yang Guo <yangguo@chromium.org>
Commit-Queue: Yang Guo <yangguo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59572}

This is a reland of c79a63e6

Original change's description:
> [nojit] Don't expose wasm in jitless mode
>
> Wasm currently still creates executable memory even in
> interpreter-only mode, and is thus unsupported in jitless mode. This
> hides wasm completely, which will help e.g. fuzzers that attempt to
> run wasm code (and currently crash on the CHECK in AddOwnedCode).
>
> Bug: v8:7777,chromium:931068
> Change-Id: Iee692cb947d482ba16fb0f4da32490d42d5daef8
> Reviewed-on: https://chromium-review.googlesource.com/c/1470124
> Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
> Commit-Queue: Jakob Gruber <jgruber@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#59561}

Tbr: mstarzinger@chromium.org
Bug: v8:7777, chromium:931068
Change-Id: I535c3f598c90cd5c4072a73544cc33c5bf5460c1
Reviewed-on: https://chromium-review.googlesource.com/c/1470132Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59571}

This reverts commit c79a63e6.

Reason for revert: Needs addtl test skips: https://chromium-review.googlesource.com/c/1470124

Original change's description:
> [nojit] Don't expose wasm in jitless mode
> 
> Wasm currently still creates executable memory even in
> interpreter-only mode, and is thus unsupported in jitless mode. This
> hides wasm completely, which will help e.g. fuzzers that attempt to
> run wasm code (and currently crash on the CHECK in AddOwnedCode).
> 
> Bug: v8:7777,chromium:931068
> Change-Id: Iee692cb947d482ba16fb0f4da32490d42d5daef8
> Reviewed-on: https://chromium-review.googlesource.com/c/1470124
> Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
> Commit-Queue: Jakob Gruber <jgruber@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#59561}

TBR=mstarzinger@chromium.org,jgruber@chromium.org

Change-Id: Ic242db3efe73ef362e0f0c3efde90682db6de4a8
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:7777, chromium:931068
Reviewed-on: https://chromium-review.googlesource.com/c/1470131Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59570}

We'll let the bytecode compiler and optimizing compilers deal with dead code,
rather than the ast visitors. The problem is that the visitors previously
disagreed upon what was dead. That's bad if necessary visitors omit parts of
the code that the bytecode generator will actually visit.

I did consider removing the AST nodes immediately in the parser, but that
adds overhead and actually broke code coverage. Since dead code shouldn't be
shipped to the browser anyway (and we can still omit it later in the bytecode
generator), I opted for keeping the nodes instead.

Change-Id: Ib02fa9031b17556d2e1d46af6648356486f8433d
Reviewed-on: https://chromium-review.googlesource.com/c/1470108
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59569}

This reverts commit 74951850.

Reason for revert: Speculative revert, possibly causing an Arm failure - https://ci.chromium.org/p/v8/builders/luci.v8.ci/V8%20Linux%20-%20arm%20-%20sim%20-%20lite/2399

Original change's description:
> [wasm] Fix two jump table offset parameters.
> 
> R=​jgruber@chromium.org
> 
> Change-Id: I5b40819b1a746f16b7b18aac1bba65d83a7e3483
> Reviewed-on: https://chromium-review.googlesource.com/c/1470127
> Reviewed-by: Jakob Gruber <jgruber@chromium.org>
> Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#59560}

TBR=mstarzinger@chromium.org,jgruber@chromium.org

Change-Id: I94735b93371289f1f7d9190160b21b2eabb88b14
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/1470130Reviewed-by: Maya Lekova <mslekova@chromium.org>
Commit-Queue: Maya Lekova <mslekova@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59568}