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}

Bug:chromium:617892

Change-Id: I9993191fb632ca49f020e8073e7e409c86932a29
Reviewed-on: https://chromium-review.googlesource.com/485202
Commit-Queue: Hitoshi Yoshida <peria@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#44827}

The StringIndexOf fast path used to be very narrow, only allowing
one-byte single-char search strings (and a one-byte subject string).

This changes the CSA fast path to call into our internal SearchString C++
function instead (after attempting to unpack both Strings), and can handle
strings of arbitrary length and encoding. The only remaining runtime call is
when either string needs to be flattened.

BUG=

Review-Url: https://codereview.chromium.org/2814373002
Cr-Commit-Position: refs/heads/master@{#44718}

Taking the slow runtime path for every non-internalized string key
can be avoided by doing optimistic string table lookups: if there
is a matching entry, use that; if there isn't, then no existing
object has a property with that name.
The hashing/internalizing logic is in C++ and called directly.

Review-Url: https://codereview.chromium.org/2811333002
Cr-Commit-Position: refs/heads/master@{#44650}

This removes kDeoptTableSerializeEntryCount heuristic constant.

Review-Url: https://codereview.chromium.org/2790573002
Cr-Commit-Position: refs/heads/master@{#44379}

The last CL https://chromium-review.googlesource.com/c/456707/ caused
some pretty heavy performance regressions. After experimenting, it
seems the easiest and most straight-forward way to copy the elements
into the new typed array is to do it in JS.

Adds a fast path for typed arrays, where the source typed array has
the same elements kind, in which case we can just copy the backing
store using memcpy.

This CL also removes regression test 319120 which is from a pwn2own
vulnerability. The old code path enforced a maximum byte_length
that was too low, which this change removes. The length property of
the typed array must be a Smi, but the byte_length, which can be up
to 8x larger than length for a Float64Array, can be a heap number.

We can also re-use some of the logic from ConstructByLength when
deciding whether to allocate the buffer on- or off-heap, so that
is factored out into InitializeBasedOnLength. We can also re-use
the DoInitialize helper instead of calling into the runtime,
meaning we can remove InitializeFromArrayLike.

BUG=v8:5977,chromium:705503,chromium:705394

Change-Id: I63372652091d4bdf3a9491acef9b4e3ac793a755
Reviewed-on: https://chromium-review.googlesource.com/459621Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Peter Marshall <petermarshall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#44301}

The dotAll flag changes behavior of the dot '.' character to match every
possible single character instead of excluding certain line terminators.

The implementation is staged behind --harmony-regexp-dotall.

Spec proposal: https://github.com/mathiasbynens/es-regexp-dotall-flag

BUG=v8:6172

Review-Url: https://codereview.chromium.org/2780173002
Cr-Commit-Position: refs/heads/master@{#44295}

This requires serialized data to track the number of API-provided
external references separately.
And it flushes out a case of serialized data corruption (stored "length"
field too large) that we didn't handle without crashing.

BUG=v8:6055

Review-Url: https://codereview.chromium.org/2736923002
Cr-Commit-Position: refs/heads/master@{#43649}

Turbofan is a lot slower than Crankshaft at constructing TypedArrays,
because we always go to the C++ builtin. Port the builtin to CSA
to improve performance, and to clean up the implementation, which is
split across multiple files and pieces at the moment.

This CL increases the performance with --future to roughly the same
as with crankshaft.

BUG=v8:5977

Change-Id: Id0d91a4592de41a3a308846d79bd44a608931762
Reviewed-on: https://chromium-review.googlesource.com/448537Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Commit-Queue: Peter Marshall <petermarshall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#43548}

This reverts commit b23b2c10.

Reason for revert: Makes Linux debug bot sad

Original change's description:
> [builtins] Port TypedArrayInitialize to CodeStubAssembler.
> 
> Turbofan is a lot slower than Crankshaft at constructing TypedArrays,
> because we always go to the C++ builtin. Port the builtin to CSA
> to improve performance, and to clean up the implementation, which is
> split across multiple files and pieces at the moment.
> 
> This CL increases the performance with --future to roughly the same
> as with crankshaft.
> 
> BUG=v8:5977
> 
> Change-Id: I5a4c4b544a735a56290b85bf33c2f3718df7e2b8
> Reviewed-on: https://chromium-review.googlesource.com/445717
> Commit-Queue: Peter Marshall <petermarshall@chromium.org>
> Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
> Reviewed-by: Camillo Bruni <cbruni@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#43518}

TBR=cbruni@chromium.org,petermarshall@chromium.org,bmeurer@chromium.org,v8-reviews@googlegroups.com
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:5977

Change-Id: I5d5bc8b4677a405c716d78e688af80ae9c737b4a
Reviewed-on: https://chromium-review.googlesource.com/448558Reviewed-by: Peter Marshall <petermarshall@chromium.org>
Commit-Queue: Peter Marshall <petermarshall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#43520}

Turbofan is a lot slower than Crankshaft at constructing TypedArrays,
because we always go to the C++ builtin. Port the builtin to CSA
to improve performance, and to clean up the implementation, which is
split across multiple files and pieces at the moment.

This CL increases the performance with --future to roughly the same
as with crankshaft.

BUG=v8:5977

Change-Id: I5a4c4b544a735a56290b85bf33c2f3718df7e2b8
Reviewed-on: https://chromium-review.googlesource.com/445717
Commit-Queue: Peter Marshall <petermarshall@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#43518}

BUG=v8:5294

Change-Id: If45f25aae8de526027b7851cb4efe0ccf4a7c4b1
Reviewed-on: https://chromium-review.googlesource.com/444226
Commit-Queue: Marja Hölttä <marja@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#43388}

Due to link-time optimizations functions with same code
can be folded into one, resulting in duplicate references.

R=jochen@chromium.org, peria@chromium.org
BUG=chromium:617892

Review-Url: https://codereview.chromium.org/2707903002
Cr-Commit-Position: refs/heads/master@{#43317}

Previously, when restarting a frame, we would rewrite all frames
between the debugger activation and the frame to restart to squash
them, and replace the return address with that of a builtin to
leave that rewritten frame, and restart the function by calling it.

We now simply remember the frame to drop to, and upon returning
from the debugger, we check whether to drop the frame, load the
new FP, and restart the function.

R=jgruber@chromium.org, mstarzinger@chromium.org
BUG=v8:5587

Review-Url: https://codereview.chromium.org/2636913002
Cr-Commit-Position: refs/heads/master@{#42725}

- kDebugPromiseCreated(task, parent_task)
This event occurs when promise is created (PromiseHookType::Init). V8Debugger uses this event to maintain task -> parent task map.

- kDebugEnqueueAsyncFunction(task)
This event occurs when first internal promise for async function is created. V8Debugger collects stack trace at this point.

- kDebugEnqueuePromiseResolve(task),
This event occurs when Promise fulfills with resolved status. V8Debugger collects stack trace at this point.

- kDebugEnqueuePromiseReject(task),
This event occurs when Promise fulfills with rejected status. V8Debugger collects stack trace at this point.

- kDebugPromiseCollected,
This event occurs when Promise is collected and no other chained callbacks can be added. V8Debugger removes information about async task for this promise.

- kDebugWillHandle,
This event occurs when chained promise function (either resolve or reject handler) is called. V8Debugger installs parent promise's stack (based on task -> parent_task map) as current if available or current promise's scheduled stack otherwise.

- kDebugDidHandle,
This event occurs after chained promise function has finished. V8Debugger restores asynchronous call chain to previous one.

With this change all instrumentation calls are related to current promise (before WillHandle and DidHandle were related to next async task).

Before V8Debugger supported only the following:
- asyncTaskScheduled(task1)
- asyncTaskStarted(task1)
- asyncTaskFinished(task1)

Now V8Debugger supports the following:
- asyncTaskScheduled(parent_task)
..
- asyncTaskCreated(task, parent_task),
- asyncTaskStarted(task), uses parent_task scheduled stack
- asyncTaskScheduled(task)
- asyncTaskFinished(task)

Additionally: WillHandle and DidHandle were migrated to PromiseHook API.

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

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

Review-Url: https://codereview.chromium.org/2650803003
Cr-Commit-Position: refs/heads/master@{#42644}

R=jgruber@chromium.org, mstarzinger@chromium.org
BUG=v8:5821

Review-Url: https://codereview.chromium.org/2622863003
Cr-Commit-Position: refs/heads/master@{#42270}

This adds kInit, kResolve, kBefore and kAfter lifecycle hooks to promises.

This also exposes an API to set the PromiseHook.

BUG=v8:4643

Review-Url: https://codereview.chromium.org/2575313002
Cr-Commit-Position: refs/heads/master@{#41775}

Many websites use simple calls to String.prototype.indexOf with either a
one character ASCII needle or needles bigger than the search string. This
CL adds a TFJ builtin for these simple cases, giving up to factor 5 speedup.

Drive-by-fix: Add default Object type to Arguments.at

BUG=

Review-Url: https://codereview.chromium.org/2539093002
Cr-Commit-Position: refs/heads/master@{#41760}

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

Review-Url: https://codereview.chromium.org/2562393002
Cr-Commit-Position: refs/heads/master@{#41720}

This will be used in CSA to check if any promisehook is set.

-- Adds a is_promisehook_enabled_ field to the isolate and helper methods.
-- Adds this field to the ExternalReference table.
-- Adds a helper method to access this from CSA

Note -- this patch doesn't actually add the ability to attach the hook
yet.

BUG=v8:4643

Review-Url: https://codereview.chromium.org/2566483002
Cr-Commit-Position: refs/heads/master@{#41607}

R=jochen@chromium.org
BUG=chromium:617892

Review-Url: https://codereview.chromium.org/2561783002
Cr-Commit-Position: refs/heads/master@{#41587}

R=peria@chromium.org, vogelheim@chromium.org
BUG=chromium:617892
NOPRESUBMIT=true

Review-Url: https://codereview.chromium.org/2495213003
Cr-Commit-Position: refs/heads/master@{#40981}

Revert of [serializer] print use count of external references. (patchset #2 id:20001 of https://codereview.chromium.org/2495213003/ )

Reason for revert:
Breaks https://build.chromium.org/p/client.v8/builders/V8%20Linux%20-%20vtunejit/builds/14690 compile

Original issue's description:
> [serializer] print use count of external references.
>
> R=peria@chromium.org, vogelheim@chromium.org
> BUG=chromium:617892
> NOPRESUBMIT=true

TBR=peria@chromium.org,vogelheim@chromium.org,yangguo@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=chromium:617892

Review-Url: https://codereview.chromium.org/2498163003
Cr-Commit-Position: refs/heads/master@{#40980}

R=peria@chromium.org, vogelheim@chromium.org
BUG=chromium:617892
NOPRESUBMIT=true

Review-Url: https://codereview.chromium.org/2495213003
Cr-Commit-Position: refs/heads/master@{#40979}

Changes include:
 - Adding V8_EXPORT macro for SnapshotCreator
 - Removing outdated DCHECKs.
 - Allow nullptr as external reference. This required a...
 - Refactoring of hashmaps used by the serializer.
 - Remove external references for counters. These are not used
   anywhere for isolates that are being serialized.
 - Put template infos into the partial snapshot cache.
 - Remove unnecessary presubmit check for external references.
   mksnapshot crashes if external references are missing.

R=jochen@chromium.org, vogelheim@chromium.org
BUG=chromium:617892

Review-Url: https://codereview.chromium.org/2490783004
Cr-Commit-Position: refs/heads/master@{#40949}

RIP, handwritten KeyedLoadICStub, handwritten KeyedLoadIC_Megamorphic,
and hydrogenized KeyedLoadGeneric!

Review-Url: https://codereview.chromium.org/2424433002
Cr-Commit-Position: refs/heads/master@{#40354}

According to new store IC calling convention the value, slot and vector are passed
on the stack and there's no need in trying to preserve values or respective registers
in store handlers.

Nice bonus: we also don't need virtual registers anymore.

BUG=v8:5407

Review-Url: https://codereview.chromium.org/2357323003
Cr-Commit-Position: refs/heads/master@{#39672}

BUG=

Review-Url: https://codereview.chromium.org/2161513002
Cr-Commit-Position: refs/heads/master@{#37937}

This CL more or less reverts commit https://codereview.chromium.org/2107733002/
The use of the MathPow code stub that was introduced by that commit caused
problems on arm64, and the MathPow code stub was also an obstacle in the
implementation of parallel code generation.

In addition this CL turns on the mjsunit/wasm/embenchen tests for arm64
which were turned off because of problems with MathPow on arm64.

R=titzer@chromium.org, bradnelson@chromium.org

Review-Url: https://codereview.chromium.org/2166793002
Cr-Commit-Position: refs/heads/master@{#37911}

R=bmeurer@chromium.org
BUG=v8:5197

Review-Url: https://codereview.chromium.org/2155633002
Cr-Commit-Position: refs/heads/master@{#37820}

Now builtins are sorted by use, not implementation.

R=bmeurer@chromium.org
BUG=v8:5197

Review-Url: https://codereview.chromium.org/2145413002
Cr-Commit-Position: refs/heads/master@{#37761}

After this CL we can avoid using Code::flags in hash computations for megamorphic
stub caches and therefore the unused ICState field can be finally removed from flags.

BUG=chromium:618701

Review-Url: https://codereview.chromium.org/2123983004
Cr-Commit-Position: refs/heads/master@{#37708}

Import fdlibm versions of acos, acosh, asin and asinh, which are more
precise and produce the same result across platforms (we were using
libm versions for asin and acos so far, where both speed and precision
depended on the operating system so far). Introduce appropriate TurboFan
operators for these functions and use them both for inlining and for the
generic builtin.

Also migrate the Math.imul and Math.fround builtins to TurboFan builtins
to ensure that their behavior is always exactly the same as the inlined
TurboFan version (i.e. C++ truncation semantics for double to float
don't necessarily meet the JavaScript semantics).

For completeness, also migrate Math.sign, which can even get some nice
love in TurboFan.

Drive-by-fix: Some alpha-sorting on the Math related functions, and
cleanup the list of Math intrinsics that we have to export via the
native context currently.

BUG=v8:3266,v8:3496,v8:3509,v8:3952,v8:5169,v8:5170,v8:5171,v8:5172
TBR=rossberg@chromium.org
R=franzih@chromium.org

Review-Url: https://codereview.chromium.org/2116753002
Cr-Commit-Position: refs/heads/master@{#37476}

BUG=v8:5086

Review-Url: https://codereview.chromium.org/2083573002
Cr-Commit-Position: refs/heads/master@{#37424}

Prior to this commit, calls to C++ builtins created standard exit
frames, which are skipped when constructing JS stack traces. In order to
show these calls on traces, we introduce a new builtin exit frame type.

Builtin exit frames contain target and new.target on the stack and are
not skipped during stack trace construction.

BUG=v8:4815
R=bmeurer@chromium.org, yangguo@chromium.org
CQ_INCLUDE_TRYBOTS=tryserver.chromium.linux:linux_chromium_rel_ng;tryserver.blink:linux_blink_rel;tryserver.v8:v8_linux_nosnap_dbg

Committed: https://crrev.com/3c60c6b105f39344f93a8407f41534e5e60cf19a
Review-Url: https://codereview.chromium.org/2090723005
Cr-Original-Commit-Position: refs/heads/master@{#37384}
Cr-Commit-Position: refs/heads/master@{#37416}

Revert of [builtins] New frame type for exits to C++ builtins (patchset #5 id:80001 of https://codereview.chromium.org/2090723005/ )

Reason for revert:
Looks like this breaks on nosnap: http://build.chromium.org/p/client.v8/builders/V8%20Linux%20-%20nosnap%20-%20debug/builds/7626

Original issue's description:
> [builtins] New frame type for exits to C++ builtins
>
> Prior to this commit, calls to C++ builtins created standard exit
> frames, which are skipped when constructing JS stack traces. In order to
> show these calls on traces, we introduce a new builtin exit frame type.
>
> Builtin exit frames contain target and new.target on the stack and are
> not skipped during stack trace construction.
>
> BUG=v8:4815
> R=bmeurer@chromium.org, yangguo@chromium.org
> CQ_INCLUDE_TRYBOTS=tryserver.chromium.linux:linux_chromium_rel_ng;tryserver.blink:linux_blink_rel
>
> Committed: https://crrev.com/3c60c6b105f39344f93a8407f41534e5e60cf19a
> Cr-Commit-Position: refs/heads/master@{#37384}

TBR=yangguo@chromium.org,jgruber@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:4815

Review-Url: https://codereview.chromium.org/2106113002
Cr-Commit-Position: refs/heads/master@{#37394}

Prior to this commit, calls to C++ builtins created standard exit
frames, which are skipped when constructing JS stack traces. In order to
show these calls on traces, we introduce a new builtin exit frame type.

Builtin exit frames contain target and new.target on the stack and are
not skipped during stack trace construction.

BUG=v8:4815
R=bmeurer@chromium.org, yangguo@chromium.org
CQ_INCLUDE_TRYBOTS=tryserver.chromium.linux:linux_chromium_rel_ng;tryserver.blink:linux_blink_rel

Review-Url: https://codereview.chromium.org/2090723005
Cr-Commit-Position: refs/heads/master@{#37384}

R=bmeurer@chromium.org

BUG=v8:5086,v8:5157

Review-Url: https://codereview.chromium.org/2107733002
Cr-Commit-Position: refs/heads/master@{#37375}

Introduce a new machine operator Float64Pow that for now is backed by
the existing MathPowStub to start the unification of Math.pow, and at
the same time address the main performance issue that TurboFan still has
with the imaging-darkroom benchmark in Kraken.

Also migrate the Math.pow builtin itself to a TurboFan builtin and
remove a few hundred lines of hand-written platform code for special
handling of the fullcodegen Math.pow version.

BUG=v8:3599,v8:5086,v8:5157

Review-Url: https://codereview.chromium.org/2103733003
Cr-Commit-Position: refs/heads/master@{#37323}

R=jochen@chromium.org, vogelheim@chromium.org
BUG=chromium:617892

Review-Url: https://codereview.chromium.org/2066993004
Cr-Commit-Position: refs/heads/master@{#37109}