Intrinsic and generic lowering for generator object creation. In a follow-on, create lowering will be addressed.

BUG=v8:6352

Review-Url: https://codereview.chromium.org/2862213002
Cr-Commit-Position: refs/heads/master@{#45171}

This patch expands scope analysis to skip hole initialization
when it can be determined statically that no hole checks will
be generated at runtime.

Two conditions must be met to safely eliminate hole initialization:
  - There must not exist a VariableProxy referencing this Variable
    whose HoleCheckMode is kRequired
  - The Variable must be stack allocated; any other allocation implies
    that it may be accessed from not-yet-analyzed scopes (other modules,
    inner functions, or eval code) and that code may require
    hole checks.

The new logic required removing debug code in full-codegen which is
now incorrect in some cases.

Also fixed Variable's bitfield helpers to take no more space than needed.

Bug: chromium:651637
Change-Id: Ie5ac326af4e05b7a5c3c37cd4d0afba6a51a504d
Reviewed-on: https://chromium-review.googlesource.com/494006
Commit-Queue: Adam Klein <adamk@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45170}

This reverts commit ec619cbd.

Reason for revert: Crashing on Canary
BUG=chromium:718891

Original change's description:
> [Interpreter] Transition JSFunctions to call optimized code when possible.
> 
> Now that the optimized code hangs off the feedback vector, it is possible
> to check whether a function has optimized code available every time it's
> called in the interpreter entry trampoline. If optimized code exists, the
> interpreter entry trampoline 'self-heals' the closure to point to the
> optimized code and links the closure into the optimized code list.
> 
> BUG=v8:6246
> 
> Change-Id: If1bd7c555bb0551bfe04b36baa6bcf949604717e
> Reviewed-on: https://chromium-review.googlesource.com/488026
> Reviewed-by: Michael Stanton <mvstanton@chromium.org>
> Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#45103}

TBR=rmcilroy@chromium.org,mvstanton@chromium.org
# Not skipping CQ checks because original CL landed > 1 day ago.
BUG=v8:6246

Change-Id: Ibda719be90fddf1d116c03a2a0c3018bcbe76018
Reviewed-on: https://chromium-review.googlesource.com/498632Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45169}

The code for UMA stats (in counters.h) is not thread safe, and can
lead to using pointers with uninitialized values.

Therefore, this CL turns them off when compiling asynchronously.

It also turns back on several UMA stats that were previously turned
off, but no longer need to because the code now knows if it is
running synchronously.

BUG=v8:6361

Review-Url: https://codereview.chromium.org/2864583004
Cr-Commit-Position: refs/heads/master@{#45168}

BUG=chromium:718484

Review-Url: https://codereview.chromium.org/2867073002
Cr-Commit-Position: refs/heads/master@{#45167}

This reverts commit de964dbe.

Reason for revert:
https://build.chromium.org/p/client.v8/builders/V8%20Linux/builds/17958

Original change's description:
> Introducing an event loop mechanism for d8.
> 
> This mechanism ensures APIs like wasm async complete their work, 
> without requiring use of natives (%APIs).
> 
> The mechanism is similar to the one used in content_shell,
> which should allow us to easily port tests in that environment.
> 
> Review-Url: https://codereview.chromium.org/2842843005
> Cr-Original-Commit-Position: refs/heads/master@{#44908}
> Bug: 
> Change-Id: I9deee0d256a600c60b42902fc8ef8478e5546344
> Reviewed-on: https://chromium-review.googlesource.com/494968
> Commit-Queue: Mircea Trofin <mtrofin@google.com>
> Reviewed-by: Jochen Eisinger <jochen@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#45165}

TBR=bradnelson@chromium.org,mtrofin@chromium.org,mtrofin@google.com,jochen@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Change-Id: Iafec2615d705d1990c57229cab3a988c00b5e12f
Reviewed-on: https://chromium-review.googlesource.com/498630Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45166}

This mechanism ensures APIs like wasm async complete their work, 
without requiring use of natives (%APIs).

The mechanism is similar to the one used in content_shell,
which should allow us to easily port tests in that environment.

Review-Url: https://codereview.chromium.org/2842843005
Cr-Original-Commit-Position: refs/heads/master@{#44908}
Bug: 
Change-Id: I9deee0d256a600c60b42902fc8ef8478e5546344
Reviewed-on: https://chromium-review.googlesource.com/494968
Commit-Queue: Mircea Trofin <mtrofin@google.com>
Reviewed-by: Jochen Eisinger <jochen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45165}

Another fix for more explicit management of ownership. The
CompilationHelper now always owns the WasmModule, and transfers
ownership to the generated WasmModuleWrapper (a Managed<WasmModule>)
once that object is created. Since the stored uniqe_ptr cannot be
accessed any more after this transfer, the creation of the
WasmModuleWrapper is delayed until it is really needed (step 5 in async
compilation).

R=ahaas@chromium.org

Change-Id: I22dea2e14a364ddf76751d97bd0d736a4c0ceff4
Reviewed-on: https://chromium-review.googlesource.com/498507Reviewed-by: Andreas Haas <ahaas@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45164}

Revert of [test] add --no-harness option to debugger tests. (patchset #1 id:1 of https://codereview.chromium.org/2831083003/ )

Reason for revert:
Should define its own NO_HARNESS_PATTERN. See comments.

Original issue's description:
> [test] add --no-harness option to debugger tests.
>
> Review-Url: https://codereview.chromium.org/2831083003
> Cr-Commit-Position: refs/heads/master@{#44774}
> Committed: https://chromium.googlesource.com/v8/v8/+/43c20d4cc566c68ce0b566cad0ac6fa92bba8eff

TBR=caitp@igalia.com,yangguo@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.

Review-Url: https://codereview.chromium.org/2871593002
Cr-Commit-Position: refs/heads/master@{#45163}

BUG=v8:6093

Change-Id: I612ad27bf0bcdc30a5d2f1f86a0c31b40ab4494d
Reviewed-on: https://chromium-review.googlesource.com/493348
Commit-Queue: Wiktor Garbacz <wiktorg@google.com>
Reviewed-by: Daniel Vogelheim <vogelheim@chromium.org>
Reviewed-by: Marja Hölttä <marja@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45162}

Since the wasm module is verified before starting execution with lazy
compilation, the compilation of individual functions should not fail
later.
This CL changes the implementation to check this condition earlier
and removes unused error paths.

R=ahaas@chromium.org, mstarzinger@chromium.org
BUG=chromium:719286

Change-Id: If4bab457a47f214b457b2e2bc8570cba8c8bbcfd
Reviewed-on: https://chromium-review.googlesource.com/497755Reviewed-by: Andreas Haas <ahaas@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45161}

Make ModuleResult and FunctionResult return Result<std::unique_ptr<X>>.
This makes memory ownership and transfer of ownership more clear and
avoids a lot of manual releases of the referenced native heap object.

R=ahaas@chromium.org

Change-Id: I7a3f5bd7761b6ae1ebdc7d17ff1b96a8df599871
Reviewed-on: https://chromium-review.googlesource.com/498352Reviewed-by: Andreas Haas <ahaas@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45160}

BUG=chromium:651354

Review-Url: https://codereview.chromium.org/2871543002
Cr-Commit-Position: refs/heads/master@{#45159}

We don't currently depend on this, but it might improve performance by
avoiding intermediate copies. The functions are already set up for
perfect forwarding, but without declaring the parameters as forwarding
references, this does not work as expected.

R=ahaas@chromium.org

Change-Id: I2c4d96ea1108b3f884d3e581e74c20aafd232934
Reviewed-on: https://chromium-review.googlesource.com/497409Reviewed-by: Andreas Haas <ahaas@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45158}

Inside the CompilationHelper, we were creating another compilation
helper to execute sequential or parallel compilation.
I don't see the reason to do so.

R=ahaas@chromium.org

Change-Id: Ib2c4486296a8f923e7e38620879c02963fff7d60
Reviewed-on: https://chromium-review.googlesource.com/497754Reviewed-by: Andreas Haas <ahaas@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45157}

With this CL we share code among the wasm fuzzers which construct a
module and run it in the interpreter and as compiled code.The fuzzers
themselves only contain the code now which creates the module and the
parameters.

BUG=v8:6325
R=eholk@chromium.org

Change-Id: I1c2d8b013531c86cb27837f1b8ec89d2688c536b
Reviewed-on: https://chromium-review.googlesource.com/490048
Commit-Queue: Andreas Haas <ahaas@chromium.org>
Reviewed-by: Brad Nelson <bradnelson@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45156}

It was replaced by more generic handling  in 13206667, which
is functionally fine, but for performance it makes sense to keep
the fast path.

Review-Url: https://codereview.chromium.org/2864463004
Cr-Commit-Position: refs/heads/master@{#45155}

Also make the macro name more scary, so people don't add new calls

BUG=v8:5830
R=jgruber@chromium.org

Change-Id: I06760110b7f0429d7775345b414c75c8df5e503a
Reviewed-on: https://chromium-review.googlesource.com/497451Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Jochen Eisinger <jochen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45154}

In its destructor, the ErrorThrower already reifies exceptions and
throws them if an error has been set.

R=mtrofin@chromium.org

Change-Id: I17d7a6d300fe4a5860431f214746d053eaf9f104
Reviewed-on: https://chromium-review.googlesource.com/497467
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45153}

TBR=tebbi@chromium.org

Bug: v8:6346
Change-Id: Iea45ebaff908eb8a12ee51e220b0554241c049be
Reviewed-on: https://chromium-review.googlesource.com/497753Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45152}

Bug:v8:5510
R=yangguo@chromium.org,jgruber@chromium.org

Change-Id: Ieb355110bd858efe2495a6271ffeda67d41af129
Reviewed-on: https://chromium-review.googlesource.com/497153Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Loo Rong Jie <loorongjie@gmail.com>
Cr-Commit-Position: refs/heads/master@{#45151}

Rolling v8/build: https://chromium.googlesource.com/chromium/src/build/+log/99d7dc3..ab75dcc

TBR=machenbach@chromium.org,vogelheim@chromium.org,hablich@chromium.org

Change-Id: I280f5a79a9a44e856212acd93def75ad28b077d5
Reviewed-on: https://chromium-review.googlesource.com/498389Reviewed-by: v8 autoroll <v8-autoroll@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45150}

Rolling v8/build: https://chromium.googlesource.com/chromium/src/build/+log/225def8..99d7dc3

TBR=machenbach@chromium.org,vogelheim@chromium.org,hablich@chromium.org

Change-Id: If91d8fc6564ceb72f9bbe62be86d51d0913bf5df
Reviewed-on: https://chromium-review.googlesource.com/497952Reviewed-by: v8 autoroll <v8-autoroll@chromium.org>
Commit-Queue: v8 autoroll <v8-autoroll@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45149}

History has shown that 99.93% (or more) of all memory allocations are less
than 1 megabyte, and they all appear in the same UMA stat entry.

To give perspective, the entry for <= 1Mb is about 20,000 times larger
than any other entry in the table. This makes the distribution in the
table hard to see.

And, for allocation failures at this size, the percentage of failures
(when compared to number of requests) is soo small (millions to one)
that little data can be gleamed from the <= 1Mb entry.

Note: requires CL https://codereview.chromium.org/2867483002

BUG=chrome:704922
R=bradnelson@chromium.org, bbudge@chromium.org, isherman@chromium.org

Review-Url: https://codereview.chromium.org/2856663002
Cr-Commit-Position: refs/heads/master@{#45148}

Rolling v8/build: https://chromium.googlesource.com/chromium/src/build/+log/0fffbdf..225def8

Rolling v8/third_party/catapult: https://chromium.googlesource.com/external/github.com/catapult-project/catapult/+log/d9a6925..ada8f7c

Rolling v8/third_party/icu: https://chromium.googlesource.com/chromium/deps/icu/+log/b34251f..4b06aad

TBR=machenbach@chromium.org,vogelheim@chromium.org,hablich@chromium.org

Change-Id: I526c70a04bf757705c94096591756023d4b432d9
Reviewed-on: https://chromium-review.googlesource.com/497595Reviewed-by: v8 autoroll <v8-autoroll@chromium.org>
Commit-Queue: v8 autoroll <v8-autoroll@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45147}

After the recent fast-property deletion changes, there can be a
non-empty out-of-object backing store (that previously held properties)
even though the next double property will be stored in-object.

BUG=chromium:718779

Review-Url: https://codereview.chromium.org/2861093004
Cr-Commit-Position: refs/heads/master@{#45146}

As a first step towards improving generator creation, create a builtin
that can do it without a call to the runtime. Thread that builtin
into the interpreter via an intrinsic.

BUG=v8:6352
R=bmeurer@chromium.org

Review-Url: https://codereview.chromium.org/2861983002
Cr-Commit-Position: refs/heads/master@{#45145}

The concurrent marker now colors objects grey and black using
the atomic markbit operations.

The heap visitor is changed in two ways:
1) It iterates the map pointer of each object.
2) It guards object visitation with a predicate, which is overridden
in the concurrent marker with the result of GreyToBlack transition.

BUG=chromium:694255
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_chromium_rel_ng

Review-Url: https://codereview.chromium.org/2866473003
Cr-Commit-Position: refs/heads/master@{#45144}

At this point, last_index is definitely a canonicalized non-negative
number, which implies that any non-Smi last_index is greater than
the maximal string length. That in turn means that the matcher will
definitely fail, and we can avoid the expensive runtime call.

BUG=v8:6365,v8:6344

Review-Url: https://codereview.chromium.org/2863643004
Cr-Commit-Position: refs/heads/master@{#45143}

Adds a flag (--disable-in-process-stack-traces) to not install
signal handlers so that e.g. ASan signal handlers will work.

This flag mirrors chromium's one.

R=jochen@chromium.org
BUG=chromium:716235

Review-Url: https://codereview.chromium.org/2854173002
Cr-Commit-Position: refs/heads/master@{#45142}

This CL migrates the CPP builtin to CSA with fast paths for strings
that can be unpacked to direct one-byte strings. Short strings are
handled directly in CSA, others need to call into C for conversion.

Microbenchmarks for "abcd".toLowerCase() show speedups of 2.5x.

BUG=v8:6353,v8:6344

Review-Url: https://codereview.chromium.org/2859203002
Cr-Commit-Position: refs/heads/master@{#45141}

Forcing an object into dictionary mode now requires deleting
a property that's not the last property.

BUG=chromium:718816
NOTRY=true

Review-Url: https://codereview.chromium.org/2860403002
Cr-Commit-Position: refs/heads/master@{#45140}

Currently the VisitObject function iterates the object and then colors
it black. This does not work well with concurrent marking. The function
should instead first try to mark the object black and iterate its body
only if the color transition succeeds.

BUG=chromium:694255
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_chromium_rel_ng

Review-Url: https://codereview.chromium.org/2863933002
Cr-Commit-Position: refs/heads/master@{#45139}

concurrent marking is enabled.

This patch adds kAtomicity flag to IncrementalMarking that is set
depending on the concurrent marking compile time flag.

BUG=chromium:694255
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_chromium_rel_ng

Review-Url: https://codereview.chromium.org/2858343003
Cr-Commit-Position: refs/heads/master@{#45138}

With this adaptation build V8 in Debug mode will be finished without
error messages.

TEST=
BUG=

Review-Url: https://codereview.chromium.org/2861143002
Cr-Commit-Position: refs/heads/master@{#45137}

Now non-atomic color transition operations return a boolean indicating
whether the transition succeeded or not.

This allows to replace color check and transition operations with a
single transition operation. For example:

if (IsWhite(object)) {
  WhiteToBlack(object);
  Foo();
}

becomes

if (WhiteToBlack(object)) {
  Foo();
}

BUG=chromium:694255
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_chromium_rel_ng

Review-Url: https://codereview.chromium.org/2863703004
Cr-Commit-Position: refs/heads/master@{#45136}

CodeStubAssembler::StrictEqual is modified to collect type feedback when
requested (https://chromium-review.googlesource.com/c/483399/). There 
are a couple of Gotos introduced in that cl, which are only necessary
when collecting type feedback. Changed it to generate these Gotos only
whencollecting type feedback.

Bug: v8:4280
Change-Id: I322a6065efcfb601bd9f5dc25be6e6bb00b2d1c0
Reviewed-on: https://chromium-review.googlesource.com/496268Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Commit-Queue: Mythri Alle <mythria@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45135}

R=clemensh@chromium.org
TEST=mjsunit/asm/regress-718745
BUG=chromium:718745

Change-Id: I4d31e90d7a2bbb1d07ce946682a95582f63c7e27
Reviewed-on: https://chromium-review.googlesource.com/497469Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45134}

Bug: v8:6364,v8:6344
Change-Id: I13bf1ec89a17c64b38b757694ee8b7df30d4f45f
Reviewed-on: https://chromium-review.googlesource.com/497428
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45133}

Formal parameters of an arrow function are parsed even if the function
itself is preparsed. It is because we don't know if it is an arrow
function parameter list or just comma separated expression list.
When we parse:
 (a, b = (function c() { return a; })())
call to function c may be just part of an assignment in an expression
list, but if it's followed by:
 => { return b; }
It is an arrow function and the call to c is a default parameter.
Before we see the arrow we might have already created a parse task
to parse function c.

BUG=v8:6093

Change-Id: I59a59acfdbbfd808dab1518060748be2addcd54a
Reviewed-on: https://chromium-review.googlesource.com/493347
Commit-Queue: Wiktor Garbacz <wiktorg@google.com>
Reviewed-by: Marja Hölttä <marja@chromium.org>
Reviewed-by: Daniel Vogelheim <vogelheim@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45132}