Port 0c4b8ff4

Original Commit Message:

     - Refactor Dispatch tables to have separate function, signature tables
     - New Relocation type for WasmFunctionTableReference, assembler, compiler support.
     - RelocInfo helper functions for Wasm references

R=gdeepti@chromium.org, joransiu@ca.ibm.com, jyan@ca.ibm.com, michael_dawson@ca.ibm.com
BUG=
LOG=N

Review-Url: https://codereview.chromium.org/2625683004
Cr-Commit-Position: refs/heads/master@{#42201}

Revert of [wasm][asm.js] Enable --validate-asm by default. (patchset #1 id:1 of https://codereview.chromium.org/2624813002/ )

Reason for revert:
Breaks layout tests:
https://build.chromium.org/p/client.v8.fyi/builders/V8-Blink%20Linux%2064/builds/12554

See also:
https://github.com/v8/v8/wiki/Blink%20layout%20tests

Original issue's description:
> [wasm][asm.js] Enable --validate-asm by default.
>
> This directs all asm.js traffic via the Wasm backend.
>
> R=titzer@chromium.org,aseemgarg@chromium.org
> BUG=v8:4203
>
> Review-Url: https://codereview.chromium.org/2624813002
> Cr-Commit-Position: refs/heads/master@{#42194}
> Committed: https://chromium.googlesource.com/v8/v8/+/946cc371ed4b34d1a9f5cc615b14c41b652562ad

TBR=aseemgarg@chromium.org,titzer@chromium.org,bradnelson@google.com,bradnelson@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:4203

Review-Url: https://codereview.chromium.org/2622023002
Cr-Commit-Position: refs/heads/master@{#42200}

Revert of [wasm] Enable WASM by default (--expose-wasm=true). (patchset #2 id:20001 of https://codereview.chromium.org/2623743003/ )

Reason for revert:
arm64 gc stress:
https://build.chromium.org/p/client.v8.ports/builders/V8%20Linux%20-%20arm64%20-%20sim%20-%20gc%20stress/builds/4424

Original issue's description:
> [wasm] Enable WASM by default (--expose-wasm=true).
>
> BUG=chromium:575167
> R=rossberg@chromium.org,ahaas@chromium.org,clemensh@chromium.org,bradnelson@chromium.org
>
> Review-Url: https://codereview.chromium.org/2623743003
> Cr-Commit-Position: refs/heads/master@{#42197}
> Committed: https://chromium.googlesource.com/v8/v8/+/34b63f050b1a247bb64ddc91c967501ce04e011f

TBR=clemensh@chromium.org,ahaas@chromium.org,bradnelson@chromium.org,rossberg@chromium.org,bradnelson@google.com,titzer@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=chromium:575167

Review-Url: https://codereview.chromium.org/2626763002
Cr-Commit-Position: refs/heads/master@{#42199}

TBR=bmeurer@chromium.org
NOTRY=true
NOTREECHECKS=true

Review-Url: https://codereview.chromium.org/2621123002
Cr-Commit-Position: refs/heads/master@{#42198}

BUG=chromium:575167
R=rossberg@chromium.org,ahaas@chromium.org,clemensh@chromium.org,bradnelson@chromium.org

Review-Url: https://codereview.chromium.org/2623743003
Cr-Commit-Position: refs/heads/master@{#42197}

This is a follow-up on 45c11887, which
removed hole checks from full-codegen. Variables requiring hole checks
always go through Ignition.

R=bmeurer@chromium.org

Review-Url: https://codereview.chromium.org/2622783002
Cr-Commit-Position: refs/heads/master@{#42196}

BUG=
R=clemensh@chromium.org,verwaest@chromium.org

Review-Url: https://codereview.chromium.org/2627453006
Cr-Commit-Position: refs/heads/master@{#42195}

This directs all asm.js traffic via the Wasm backend.

R=titzer@chromium.org,aseemgarg@chromium.org
BUG=v8:4203

Review-Url: https://codereview.chromium.org/2624813002
Cr-Commit-Position: refs/heads/master@{#42194}

using newly introduced ThinStrings, which store a pointer to the actual,
internalized string they represent.

BUG=v8:4520

(Previously landed as #42168 / af51befe.

Review-Url: https://codereview.chromium.org/2549773002
Cr-Commit-Position: refs/heads/master@{#42193}

 - Refactor Dispatch tables to have separate function, signature tables
 - New Relocation type for WasmFunctionTableReference, assembler, compiler support.
 - RelocInfo helper functions for Wasm references

Review-Url: https://codereview.chromium.org/2627543003
Cr-Commit-Position: refs/heads/master@{#42192}

Asm.js modules missing exports fail to run the last phase of
validation. Adding an explicit check for this.

BUG=676573
R=titzer@chromium.org,aseemgarg@chromium.org

Review-Url: https://codereview.chromium.org/2620893002
Cr-Commit-Position: refs/heads/master@{#42191}

BUG=641885
R=titzer@chromium.org,rossberg@chromium.org

Review-Url: https://codereview.chromium.org/2620953002
Cr-Commit-Position: refs/heads/master@{#42190}

Revert of [foozzie] Pass startup test (patchset #1 id:1 of https://codereview.chromium.org/2623743004/ )

Reason for revert:
Setting the BAD_BUILDS_CHECK env variable should
be enough. Lets revert this as the code doesn't
look particularly good. There must be another
problem still that needs investigation.

Original issue's description:
> [foozzie] Pass startup test
>
> This makes sure the harness passes when called without test case.
>
> BUG=chromium:673246
> NOTRY=true
> TBR=tandrii@chromium.org,mbarbella@chromium.org
>
> Review-Url: https://codereview.chromium.org/2623743004
> Cr-Commit-Position: refs/heads/master@{#42183}
> Committed: https://chromium.googlesource.com/v8/v8/+/ede2fc1ff04ff97a466029b0ad52d3ec94780407

TBR=tandrii@chromium.org,mbarbella@chromium.org,mmoroz@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=chromium:673246

Review-Url: https://codereview.chromium.org/2628493003
Cr-Commit-Position: refs/heads/master@{#42189}

R=verwaest@chromium.org
BUG=

Review-Url: https://codereview.chromium.org/2627543004
Cr-Commit-Position: refs/heads/master@{#42188}

Including a fix: object-macros.h needs to be the last include: otherwise
we'll have a problem when a file does this:

#include "object-macros.h"
#include "x.h" // x.h also includes object-macros.h

BUG=v8:5402

Review-Url: https://codereview.chromium.org/2623573003
Cr-Commit-Position: refs/heads/master@{#42187}

BUG=

Review-Url: https://codereview.chromium.org/2626603002
Cr-Commit-Position: refs/heads/master@{#42186}

... and reshuffle it a bit.

BUG=v8:5495

Review-Url: https://codereview.chromium.org/2619823005
Cr-Commit-Position: refs/heads/master@{#42185}

R=titzer@chromium.org
BUG=v8:5817

Review-Url: https://codereview.chromium.org/2620783005
Cr-Commit-Position: refs/heads/master@{#42184}

This makes sure the harness passes when called without test case.

BUG=chromium:673246
NOTRY=true
TBR=tandrii@chromium.org,mbarbella@chromium.org

Review-Url: https://codereview.chromium.org/2623743004
Cr-Commit-Position: refs/heads/master@{#42183}

Revert of [build] Introduce an embedder version string (patchset #2 id:20001 of https://codereview.chromium.org/2619213002/ )

Reason for revert:
Seems to break the Chromium build: https://codereview.chromium.org/2619193005/

Message:

[1832/9671] CXX obj/v8/v8_base/version.o
FAILED: obj/v8/v8_base/version.o
/b/c/cipd/goma/gomacc ../../third_party/llvm-build/Release+Asserts/bin/clang++ -MMD -MF obj/v8/v8_base/version.o.d -DV8_DEPRECATION_WARNINGS -DDCHECK_ALWAYS_ON=1 -DUSE_UDEV -DUI_COMPOSITOR_IMAGE_TRANSPORT -DUSE_AURA=1 -DUSE_PANGO=1 -DUSE_CAIRO=1 -DUSE_GLIB=1 -DUSE_NSS_CERTS=1 -DUSE_X11=1 -DUSE_PROPRIETARY_CODECS -DFULL_SAFE_BROWSING -DSAFE_BROWSING_CSD -DSAFE_BROWSING_DB_LOCAL -DCHROMIUM_BUILD -DENABLE_MEDIA_ROUTER=1 -DFIELDTRIAL_TESTING_ENABLED -DCR_CLANG_REVISION=289944-2 -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -DNDEBUG -DNVALGRIND -DDYNAMIC_ANNOTATIONS_ENABLED=0 -DV8_I18N_SUPPORT -DENABLE_HANDLE_ZAPPING -DV8_USE_EXTERNAL_STARTUP_DATA -DV8_TARGET_ARCH_X64 -DDEBUG -DU_USING_ICU_NAMESPACE=0 -DU_ENABLE_DYLOAD=0 -DU_STATIC_IMPLEMENTATION -DICU_UTIL_DATA_IMPL=ICU_UTIL_DATA_FILE -I../.. -Igen -I../../v8 -I../../v8/include -I../../third_party/icu/source/common -I../../third_party/icu/source/i18n -fno-strict-aliasing --param=ssp-buffer-size=4 -fstack-protector -funwind-tables -fPIC -pipe -B../../third_party/binutils/Linux_x64/Release/bin -fcolor-diagnostics -fdebug-prefix-map=/b/c/b/linux/src=. -m64 -march=x86-64 -pthread -g1 --sysroot=../../build/linux/debian_wheezy_amd64-sysroot -fvisibility=hidden -Xclang -load -Xclang ../../third_party/llvm-build/Release+Asserts/lib/libFindBadConstructs.so -Xclang -add-plugin -Xclang find-bad-constructs -Xclang -plugin-arg-find-bad-constructs -Xclang check-ipc -Wheader-hygiene -Wstring-conversion -Wtautological-overlap-compare -Werror -Wall -Wno-unused-variable -Wno-missing-field-initializers -Wno-unused-parameter -Wno-c++11-narrowing -Wno-covered-switch-default -Wno-deprecated-register -Wno-unneeded-internal-declaration -Wno-inconsistent-missing-override -Wno-shift-negative-value -Wno-undefined-var-template -Wno-nonportable-include-path -Wno-address-of-packed-member -Wsign-compare -Winconsistent-missing-override -Wshorten-64-to-32 -O3 -fno-ident -fdata-sections -ffunction-sections -fno-threadsafe-statics -fvisibility-inlines-hidden -std=gnu++11 -fno-rtti -fno-exceptions -Wno-deprecated -c ../../v8/src/version.cc -o obj/v8/v8_base/version.o
../../v8/src/version.cc:42:34: error: use of undeclared identifier 'V8_EMBEDDER_STRING'
const char* Version::embedder_ = V8_EMBEDDER_STRING;
                                 ^
1 error generated.

Original issue's description:
> [build] Introduce an embedder version string
>
> Sometimes, the embedder might want to merge a fix to an abandoned branch
> or to a supported branch but the fix is not relevant to Chromium.
> This adds a new version string that the embedder can set on compile time
> and that will be appended to the official V8 version.
> The separator must be provided in the string. For instance, to have a
> full version string like "5.5.372.37.custom.1", the embedder must set
> V8_EMBEDDER_STRING to ".custom.1".
>
> Related Node.js issue: https://github.com/nodejs/node/pull/9754
>
> BUG=v8:5740
> R=machenbach@chromium.org,hablich@chromium.com,ofrobots@google.com
>
> Review-Url: https://codereview.chromium.org/2619213002
> Cr-Commit-Position: refs/heads/master@{#42175}
> Committed: https://chromium.googlesource.com/v8/v8/+/fc86d4329b253bf21c1dd85469f1ef4b6e5ba01a

TBR=hablich@chromium.com,machenbach@chromium.org,ofrobots@google.com,mic.besace@gmail.com
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:5740

Review-Url: https://codereview.chromium.org/2621033002
Cr-Commit-Position: refs/heads/master@{#42182}

Please take a special look at the code I generate to call the runtime
function for the traps. The correct handling of csp vs jssp seems to be
quite tricky.

Original commit message:
[wasm] Introduce the TrapIf and TrapUnless operators to generate trap code.

Some instructions in WebAssembly trap for some inputs, which means that the
execution is terminated and (at least at the moment) a JavaScript exception is
thrown. Examples for traps are out-of-bounds memory accesses, or integer
divisions by zero.

Without the TrapIf and TrapUnless operators trap check in WebAssembly introduces 5
TurboFan nodes (branch, if_true, if_false, trap-reason constant, trap-position
constant), in addition to the trap condition itself. Additionally, each
WebAssembly function has four TurboFan nodes (merge, effect_phi, 2 phis) whose
number of inputs is linear to the number of trap checks in the function.
Especially for functions with high numbers of trap checks we observe a
significant slowdown in compilation time, down to 0.22 MiB/s in the sqlite
benchmark instead of the average of 3 MiB/s in other benchmarks. By introducing
a TrapIf common operator only a single node is necessary per trap check, in
addition to the trap condition. Also the nodes which are shared between trap
checks (merge, effect_phi, 2 phis) would disappear. First measurements suggest a
speedup of 30-50% on average.

This CL only implements TrapIf and TrapUnless on x64. The implementation is also
hidden behind the --wasm-trap-if flag.

Please take a special look at how the source position is transfered from the
instruction selector to the code generator, and at the context that is used for
the runtime call.

R=titzer@chromium.org, georgia.kouveli@arm.com, v8-arm-ports@googlegroups.com

Review-Url: https://codereview.chromium.org/2619203005
Cr-Commit-Position: refs/heads/master@{#42181}

R=verwaest@chromium.org,epertoso@chromium.org
BUG=

Review-Url: https://codereview.chromium.org/2620713003
Cr-Commit-Position: refs/heads/master@{#42180}

Node::InputCount() and ::InputAt() have to check for inline/out-of-line
inputs every time they are called. The compiler doesn't seem to be very
good at caching the result of this check, meaning that it (and all its
jumps) would happen for every node access.

Previously we would get around this sometimes, by using Node::inputs(),
which returned a Node::Inputs iterable over node inputs. However,
sometimes node access is more convenient using an index, or we also
want to access the count. This patch adds an index accessor and 'count'
method to Node::Inputs, and replaces several uses of InputCount and
InputAt with this accessor.

Review-Url: https://codereview.chromium.org/2617123002
Cr-Commit-Position: refs/heads/master@{#42179}

... which were done after the promise has been resolved.

Goal of this CL - change promise instrumentation to support better callbacks, chained after promise resolution and prepare instrumentation for adding new asyncTaskCreated instrumentation.

Instrumentation changes:
- asyncTaskScheduled(recurring) when promise is fulfilled or rejected,
- asyncTaskCancelled when promise is collected (since [1] we can be sure that promise will survive scheduled microtasks).

Minor changes:
- async task type in inspector <-> debugger API transferred by enum instead of string,
- Debug manages async task ids based on promise objects.

More details: https://docs.google.com/document/d/1u19N45f1gSF7M39mGsycJEK3IPyJgIXCBnWyiPeuJFE

[1] https://codereview.chromium.org/2581503003/

BUG=chromium:632829,v8:5738
R=dgozman@chromium.org,yangguo@chromium.org,gsathya@chromium.org

Review-Url: https://codereview.chromium.org/2578923002
Cr-Commit-Position: refs/heads/master@{#42178}

... including property reconfiguring, elements kind change and migration
of a map to an up-to-date non-deprecated version.

BUG=v8:5495

Review-Url: https://codereview.chromium.org/2601643002
Cr-Commit-Position: refs/heads/master@{#42177}

- Disassembler, simulator support too.
LOG=N
BUG=v8:4124

Review-Url: https://codereview.chromium.org/2600153002
Cr-Commit-Position: refs/heads/master@{#42176}

Sometimes, the embedder might want to merge a fix to an abandoned branch
or to a supported branch but the fix is not relevant to Chromium.
This adds a new version string that the embedder can set on compile time
and that will be appended to the official V8 version.
The separator must be provided in the string. For instance, to have a
full version string like "5.5.372.37.custom.1", the embedder must set
V8_EMBEDDER_STRING to ".custom.1".

Related Node.js issue: https://github.com/nodejs/node/pull/9754

BUG=v8:5740
R=machenbach@chromium.org,hablich@chromium.com,ofrobots@google.com

Review-Url: https://codereview.chromium.org/2619213002
Cr-Commit-Position: refs/heads/master@{#42175}

Now we have declarations too, so it doesn't matter whether preparser
produces the same unresolved variables as the parser.

BUG=v8:5501, v8:5516
R=verwaest@chromium.org

Review-Url: https://codereview.chromium.org/2623583004
Cr-Commit-Position: refs/heads/master@{#42174}

BUG=chromium:679345
R=verwaest@chromium.org

Review-Url: https://codereview.chromium.org/2622873002
Cr-Commit-Position: refs/heads/master@{#42173}

BUG=v8:5620
R=titzer@chromium.org

Review-Url: https://codereview.chromium.org/2620973002
Cr-Commit-Position: refs/heads/master@{#42172}

BUG=v8:5269

Review-Url: https://codereview.chromium.org/2623483002
Cr-Commit-Position: refs/heads/master@{#42171}

Revert of Internalize strings in-place (patchset #16 id:300001 of https://codereview.chromium.org/2549773002/ )

Reason for revert:
gc stress failures:
https://build.chromium.org/p/client.v8/builders/V8%20Linux%20-%20gc%20stress/builds/8024

Original issue's description:
> Internalize strings in-place
>
> using newly introduced ThinStrings, which store a pointer to the actual,
> internalized string they represent.
>
> BUG=v8:4520
>
> Review-Url: https://codereview.chromium.org/2549773002
> Cr-Commit-Position: refs/heads/master@{#42168}
> Committed: https://chromium.googlesource.com/v8/v8/+/af51befe694fe039db3554d4b9165f7d6baceb77

TBR=ishell@chromium.org,hpayer@chromium.org,bmeurer@chromium.org,jkummerow@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:4520

Review-Url: https://codereview.chromium.org/2621913002
Cr-Commit-Position: refs/heads/master@{#42170}

This adds tracking the following:
- Let / var declarations in for loops

BUG=v8:5501, v8:5516

Review-Url: https://codereview.chromium.org/2616393002
Cr-Commit-Position: refs/heads/master@{#42169}

using newly introduced ThinStrings, which store a pointer to the actual,
internalized string they represent.

BUG=v8:4520

Review-Url: https://codereview.chromium.org/2549773002
Cr-Commit-Position: refs/heads/master@{#42168}

Related to:
https://chromium-review.googlesource.com/c/426618

BUG=chromium:673246
NOTRY=true
NOTREECHECKS=true
TBR=tandrii@chromium.org,jochen@chromium.org

Review-Url: https://codereview.chromium.org/2628483003
Cr-Commit-Position: refs/heads/master@{#42167}

This adds the correctness fuzzer harness files to the output
directory guarded by a gn arg.

The switch will be turned on on the builder uploading builds to
clusterfuzz.

BUG=chromium:673246
NOTRY=true
TBR=tandrii@chromium.org,jochen@chromium.org

Review-Url: https://codereview.chromium.org/2623843002
Cr-Commit-Position: refs/heads/master@{#42166}

BUG=v8:5402

Review-Url: https://codereview.chromium.org/2628473003
Cr-Commit-Position: refs/heads/master@{#42165}

BUG=v8:5766
R=ahaas@chromium.org
NOTRY=true

Review-Url: https://codereview.chromium.org/2622863002
Cr-Commit-Position: refs/heads/master@{#42164}

R=clemensh@chromium.org
BUG=chromium:663994

Review-Url: https://codereview.chromium.org/2622563002
Cr-Commit-Position: refs/heads/master@{#42163}

Revert of [WASM] Fix failing Wasm SIMD F32x4 tests. (patchset #7 id:130001 of https://codereview.chromium.org/2594043002/ )

Reason for revert:
F32x4Add / Sub are still failing. I'll have to investigate on ARM hardware when I get back.

Original issue's description:
> [WASM] Fix failing Wasm SIMD F32x4 tests.
> - Perform lane checks using FP compare instead of reinterpret casts. 0 and -0
> will be different under I32 compare.
> - Some arithmetic operations can generate NaN results, such as adding -Inf
> and +Inf. Skip these tests until we have a way to do more sophisticated
> FP comparisons in the SIMD tests.
> - Eliminate a redundant F32x4 parameter for FP SIMD vector checking. We will only have this one FP type.
>
> LOG=N
> BUG=v8:4124
>
> Review-Url: https://codereview.chromium.org/2594043002
> Cr-Commit-Position: refs/heads/master@{#42154}
> Committed: https://chromium.googlesource.com/v8/v8/+/5560bbb498252334595a39bb5f313ac8eb82cfe1

TBR=titzer@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:4124

Review-Url: https://codereview.chromium.org/2624713002
Cr-Commit-Position: refs/heads/master@{#42162}