Previously, Date.toString() and friends were completely
implementation-defined. However, they actually seemed to match
each other's behavior with the exception of how years less than
1000 are formatted. The rough consensus among browsers seemed
to be %04d, so this was standardized at TC39 [1]. V8 previously
used %4d (it was the only one to do so); this patch adopts
the new standard.

[1] https://github.com/tc39/ecma262/commit/5d4acf3377e1b0ad4a4660c57108db1b28ef20ff

Bug: v8:6076
Change-Id: I8c795a4e1b71187ad7c24a1aee8d7d66719a2586
Reviewed-on: https://chromium-review.googlesource.com/536733
Commit-Queue: Daniel Ehrenberg <littledan@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46037}

For each Managed<T> (which is a Foreign), we create a weak global handle
with a finalizer which deletes the referenced C++ object once the
Foreign is dead.
Before calling this finalizer, the garbage collector needs to mark the
referenced object black (i.e. live), because the finalizer might
resurrect it.
Since this is never done for managed objects, we can use the more
lightweight phantom handle semantics, which allows the referenced
object to be garbage collected right away.

However, we can't access the global handle via the WeakCallbackInfo,
because the global handle will already be garbage collected. So we need
to store it explicitly. This is solved by storing the global handle
together with the finalizer.
In order to implement this, ownership of the ManagedObjectFinalizer
is moved from the isolate to the managed object.

R=ulan@chromium.org, mtrofin@chromium.org
BUG=v8:6505, chromium:734345

Change-Id: I94a245df601f70e19355d82439d30099e159231b
Reviewed-on: https://chromium-review.googlesource.com/539578
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46036}

This test checks how much time we spent for generating Debugger.paused notification.

R=machenbach@chromium.org

Bug: chromium:688036
Change-Id: Ie8a52aafe6c8d93401b0b2a90a202ddff7de78ef
Reviewed-on: https://chromium-review.googlesource.com/538584
Commit-Queue: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46035}

Bug: v8:6443
Cq-Include-Trybots: master.tryserver.chromium.linux:linux_chromium_rel_ng
Change-Id: I20b1006a5c5ff24a730f15286cf0f340ba047b78
Reviewed-on: https://chromium-review.googlesource.com/526001Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Sathya Gunasekaran <gsathya@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46034}

Bug: chromium:734162, chromium:734051, v8:6211
Change-Id: I5c3e7578e9278b8f19ff16ad4d963f490dcc6c8c
Reviewed-on: https://chromium-review.googlesource.com/541415
Commit-Queue: Camillo Bruni <cbruni@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46033}

During minor MC new space evacuation we could have two adjacent LABs
sharing a mark bit cell. The DCHECK when observing and changing markbits
of the target needs to reflect that.

Bug: chromium:651354
Change-Id: I737d0f9e3d37dfb1cda3f126d37ed5e7123bedc9
Reviewed-on: https://chromium-review.googlesource.com/541296Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46032}

With the exception for map space we can avoid atomic access at all since
pages are locked.

Map space is different since it contains old to new poitners to
LayoutDescriptors that are concurrently used by other tasks for
iterating objects.

Bug: chromium:651354
Change-Id: If7ed99d21676bad8d2944132fb9696ff4123624d
Reviewed-on: https://chromium-review.googlesource.com/539642
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46031}

This is to help the transition to using CSP as the stack pointer.
It does not make JSSP aligned yet, just makes sure that we only modify
JSSP by a multiple of 16 bytes. To do this, we might need to add a padding
slot above the receiver.

BUG=

Review-Url: https://codereview.chromium.org/2938603002
Cr-Commit-Position: refs/heads/master@{#46030}

It is possible that the foreground task is unable to clear the
scheduled unfinished work, eventually leading to an OOM.

We use either code_range on 64 bit, or the capacity of the code space,
as a heuristic for how much memory to use for compilation.

The change avoids blocking the background threads while we're over
the memory threshold. This is to avoid starving the GC.

Bug: v8:6492, chromium:732010
Change-Id: Ic2647d9fa71af4f8cdd2149a434b107cbed3a6c3
Reviewed-on: https://chromium-review.googlesource.com/540763
Commit-Queue: Mircea Trofin <mtrofin@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46029}

Change-Id: Icac68bc8fe1ae3b8f70003e001b45b3f22dac511
Reviewed-on: https://chromium-review.googlesource.com/541338Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46028}

Python List Comprehension does not need join() (alias of os.path.join).

Change-Id: I9d5a8610d88c35fd4e3cb101bc10b25c3d1dd7cf
Reviewed-on: https://chromium-review.googlesource.com/538453Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Loo Rong Jie <loorongjie@gmail.com>
Cr-Commit-Position: refs/heads/master@{#46027}

The initial implementation did not work in certain cases.
For example, in the following case 'f' didn't have a shared name while
it should have had an empty shared name:
  var f = (function() { return function() { return 42; } }();

The new implementation ensures that all anonymous functions have empty
shared name and if any of them happen to be an object literal property
value or an accessor function or a concise method then such a function
is marked as having no shared name.

Bug: v8:6459
Change-Id: I0f936afce0c152d91b2b41c1dc475a5ed841eca0
Reviewed-on: https://chromium-review.googlesource.com/538666Reviewed-by: Marja Hölttä <marja@chromium.org>
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46026}

Those sets are to be released on the main thread without concurrent
accesses. Making this explicit will give TSAN a chance to help us once
the surrounding code changes.

Bug: 
Change-Id: Ia73754caafbeec385d4c922fb8140e3e64f7378c
Reviewed-on: https://chromium-review.googlesource.com/541375Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46025}

These are no longer being used.

BUG=v8:6408

Review-Url: https://codereview.chromium.org/2944013002
Cr-Commit-Position: refs/heads/master@{#46024}

This reverts commit 1835b4b1.

Reason for revert: This has a perf regression, wasn't ready just yet.

Original change's description:
> Revert "Revert "[wasm] Throttle the amount of unfinished work to avoid OOM""
> 
> This reverts commit 4ee49181.
> 
> Reason for revert: Fix: in d8, blocking all the bg threads starves the GC.
> 
> Original change's description:
> > Revert "[wasm] Throttle the amount of unfinished work to avoid OOM"
> > 
> > This reverts commit 1280954d.
> > 
> > Reason for revert: Speculative, GC stress bots started taking much longer after this change.
> > 
> > Original change's description:
> > > [wasm] Throttle the amount of unfinished work to avoid OOM
> > > 
> > > It is possible that the foreground task is unable to clear the
> > > scheduled unfinished work, eventually leading to an OOM.
> > > 
> > > We use either code_range on 64 bit, or the capacity of the code space,
> > > as a heuristic for how much memory to use for compilation.
> > > 
> > > Bug: v8:6492, chromium:732010
> > > Change-Id: I1e4c0825351a42fa0b8369ccc41800ac3445563d
> > > Reviewed-on: https://chromium-review.googlesource.com/535017
> > > Commit-Queue: Brad Nelson <bradnelson@chromium.org>
> > > Reviewed-by: Brad Nelson <bradnelson@chromium.org>
> > > Cr-Commit-Position: refs/heads/master@{#46017}
> > 
> > TBR=bradnelson@chromium.org,mtrofin@chromium.org,ahaas@chromium.org
> > 
> > Change-Id: I8883cee7f77667530bc50f91bfb468c485e6f7f2
> > No-Presubmit: true
> > No-Tree-Checks: true
> > No-Try: true
> > Bug: v8:6492, chromium:732010
> > Reviewed-on: https://chromium-review.googlesource.com/540270
> > Reviewed-by: Bill Budge <bbudge@chromium.org>
> > Commit-Queue: Bill Budge <bbudge@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#46020}
> 
> TBR=bradnelson@chromium.org,bbudge@chromium.org,mtrofin@chromium.org,ahaas@chromium.org
> 
> Change-Id: I1e7a1d0202c3161f9a7139e8895eebf472473ad3
> No-Presubmit: true
> No-Tree-Checks: true
> No-Try: true
> Bug: v8:6492, chromium:732010
> Reviewed-on: https://chromium-review.googlesource.com/540841
> Reviewed-by: Brad Nelson <bradnelson@chromium.org>
> Reviewed-by: Mircea Trofin <mtrofin@chromium.org>
> Commit-Queue: Brad Nelson <bradnelson@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#46022}

TBR=bradnelson@chromium.org,bbudge@chromium.org,mtrofin@chromium.org,mtrofin@google.com,ahaas@chromium.org

Change-Id: Ic1351325173b233be3972ff3c159c035838fa963
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:6492, chromium:732010
Reviewed-on: https://chromium-review.googlesource.com/540842Reviewed-by: Mircea Trofin <mtrofin@chromium.org>
Commit-Queue: Mircea Trofin <mtrofin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46023}

This reverts commit 4ee49181.

Reason for revert: Fix: in d8, blocking all the bg threads starves the GC.

Original change's description:
> Revert "[wasm] Throttle the amount of unfinished work to avoid OOM"
> 
> This reverts commit 1280954d.
> 
> Reason for revert: Speculative, GC stress bots started taking much longer after this change.
> 
> Original change's description:
> > [wasm] Throttle the amount of unfinished work to avoid OOM
> > 
> > It is possible that the foreground task is unable to clear the
> > scheduled unfinished work, eventually leading to an OOM.
> > 
> > We use either code_range on 64 bit, or the capacity of the code space,
> > as a heuristic for how much memory to use for compilation.
> > 
> > Bug: v8:6492, chromium:732010
> > Change-Id: I1e4c0825351a42fa0b8369ccc41800ac3445563d
> > Reviewed-on: https://chromium-review.googlesource.com/535017
> > Commit-Queue: Brad Nelson <bradnelson@chromium.org>
> > Reviewed-by: Brad Nelson <bradnelson@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#46017}
> 
> TBR=bradnelson@chromium.org,mtrofin@chromium.org,ahaas@chromium.org
> 
> Change-Id: I8883cee7f77667530bc50f91bfb468c485e6f7f2
> No-Presubmit: true
> No-Tree-Checks: true
> No-Try: true
> Bug: v8:6492, chromium:732010
> Reviewed-on: https://chromium-review.googlesource.com/540270
> Reviewed-by: Bill Budge <bbudge@chromium.org>
> Commit-Queue: Bill Budge <bbudge@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#46020}

TBR=bradnelson@chromium.org,bbudge@chromium.org,mtrofin@chromium.org,ahaas@chromium.org

Change-Id: I1e7a1d0202c3161f9a7139e8895eebf472473ad3
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:6492, chromium:732010
Reviewed-on: https://chromium-review.googlesource.com/540841Reviewed-by: Brad Nelson <bradnelson@chromium.org>
Reviewed-by: Mircea Trofin <mtrofin@chromium.org>
Commit-Queue: Brad Nelson <bradnelson@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46022}

Rolling v8/build: https://chromium.googlesource.com/chromium/src/build/+log/bf51d56..97e4bb9

Rolling v8/buildtools: https://chromium.googlesource.com/chromium/buildtools/+log/ee9c3a7..9a65473

Rolling v8/third_party/catapult: https://chromium.googlesource.com/external/github.com/catapult-project/catapult/+log/57e600c..c2d7f3a

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

Change-Id: I07f5b7705651eec34733919182793ee6981b067c
Reviewed-on: https://chromium-review.googlesource.com/541056Reviewed-by: v8 autoroll <v8-autoroll@chromium.org>
Commit-Queue: v8 autoroll <v8-autoroll@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46021}

This reverts commit 1280954d.

Reason for revert: Speculative, GC stress bots started taking much longer after this change.

Original change's description:
> [wasm] Throttle the amount of unfinished work to avoid OOM
> 
> It is possible that the foreground task is unable to clear the
> scheduled unfinished work, eventually leading to an OOM.
> 
> We use either code_range on 64 bit, or the capacity of the code space,
> as a heuristic for how much memory to use for compilation.
> 
> Bug: v8:6492, chromium:732010
> Change-Id: I1e4c0825351a42fa0b8369ccc41800ac3445563d
> Reviewed-on: https://chromium-review.googlesource.com/535017
> Commit-Queue: Brad Nelson <bradnelson@chromium.org>
> Reviewed-by: Brad Nelson <bradnelson@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#46017}

TBR=bradnelson@chromium.org,mtrofin@chromium.org,ahaas@chromium.org

Change-Id: I8883cee7f77667530bc50f91bfb468c485e6f7f2
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:6492, chromium:732010
Reviewed-on: https://chromium-review.googlesource.com/540270Reviewed-by: Bill Budge <bbudge@chromium.org>
Commit-Queue: Bill Budge <bbudge@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46020}

Adds a 'performance' test which tracks the number of expressions
which can be nested before the compiler runs out of stack space.
This isn't really a performance test, but is created as a js-perf-test
to enable regression tracking in the dashboards.

Change-Id: Iee0c00df53b38b083e2dde09676ac9b13e439461
Reviewed-on: https://chromium-review.googlesource.com/539419Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46019}

BUG: v8:6020
Change-Id: I7280827aa9a493677253cc2fbd42be8173b55b7a
Reviewed-on: https://chromium-review.googlesource.com/534956Reviewed-by: Martyn Capewell <martyn.capewell@arm.com>
Reviewed-by: Mircea Trofin <mtrofin@chromium.org>
Commit-Queue: Bill Budge <bbudge@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46018}

It is possible that the foreground task is unable to clear the
scheduled unfinished work, eventually leading to an OOM.

We use either code_range on 64 bit, or the capacity of the code space,
as a heuristic for how much memory to use for compilation.

Bug: v8:6492, chromium:732010
Change-Id: I1e4c0825351a42fa0b8369ccc41800ac3445563d
Reviewed-on: https://chromium-review.googlesource.com/535017
Commit-Queue: Brad Nelson <bradnelson@chromium.org>
Reviewed-by: Brad Nelson <bradnelson@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46017}

 - Use correct prefixes for SIMD/Atomics ops
 - S128 LoadMem/StoreMem should not use 0xc0/0xc1 opcodes, these are now
 being used for sign extension
 - S128 LoadMem/StoreMem should use prefixed opcodes

BUG=v8:6020

Review-Url: https://codereview.chromium.org/2943773002
Cr-Commit-Position: refs/heads/master@{#46016}

This patch updates the error positition and the error msg.

Previously,

  → ./out.gn/x64.release/d8 test.js
  test.js:1: TypeError: undefined is not a function
  var [a] = {};
  ^
  TypeError: undefined is not a function
      at test.js:1:1


With this patch,

  → ./out.gn/x64.release/d8 test.js
  test.js:1: TypeError: [Symbol.iterator] is not a function
  var [a] = {};
            ^
  TypeError: [Symbol.iterator] is not a function
      at test.js:1:11

Bug: v8:5532
Change-Id: Ib066e8ec8a53fdf06cce491bde4b1d0c6d564cbc
Reviewed-on: https://chromium-review.googlesource.com/539024Reviewed-by: Adam Klein <adamk@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Commit-Queue: Sathya Gunasekaran <gsathya@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46015}

Merge OLD_TO_OLD and OLD_TO_NEW per page. This enables removing atomic
operations for the slot updates, effectively removing the need for
fences.

Bug: chromium:651354
Change-Id: I9e318bef06c403b135d638cf94fda9569dcf0e36
Reviewed-on: https://chromium-review.googlesource.com/539338
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46014}

For functions without any calls, there is no value in executing a stack
check. The current frame is materialized at that point anyway.
Note that for loops, we still emit additional stack checks in the loop
header.

For unity, the reduction in code size is moderate (0.53%), as only 4000
of the 34000 functions are leaf functions (no calls). However, we also
save some compile time and gain performance, so this is still worth
doing it.

Drive-by: Fix the effect chain generated in {StackCheck()}.

R=mstarzinger@chromium.org, ahaas@chromium.org

Change-Id: Ia6ec58d0ea46de02634c923cdf8e6e08d8902c59
Reviewed-on: https://chromium-review.googlesource.com/533333Reviewed-by: Andreas Haas <ahaas@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46013}

We only need to use this for certain Intrinsics defined in the spec.
This CL removes unnecessary uses.

Bug: v8:6474
Change-Id: I13a9f0c57d877dd65a883a38f9683d55623030d3
Reviewed-on: https://chromium-review.googlesource.com/529224
Commit-Queue: Peter Marshall <petermarshall@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46012}

This avoids emitting the costly barriers on arm.

Bug: chromium:651354
Change-Id: Ibb29e58f7c41aab37ed5c4971b2a754b4ecd7155
Reviewed-on: https://chromium-review.googlesource.com/533337
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46011}

Change-Id: If0f80ceac9582f5bd0f9177db67b2a833fa8c8cd
Reviewed-on: https://chromium-review.googlesource.com/539418Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46010}

R=rmcilroy@chromium.org
BUG=v8:6408

Change-Id: I724a14e4f3b9395eed5d56ec3b5f7be835e9390a
Reviewed-on: https://chromium-review.googlesource.com/539595Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46009}

Change-Id: I0aa40ce54833c81a15a6dd0010b2eeb46799a984
Reviewed-on: https://chromium-review.googlesource.com/539519Reviewed-by: Peter Marshall <petermarshall@chromium.org>
Commit-Queue: Camillo Bruni <cbruni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46008}

Move obvious candidates to the cc file.

Bug: 
Change-Id: I9b2bca0ed1f2836a4873760d6677a9c0dff9c064
Reviewed-on: https://chromium-review.googlesource.com/538664Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46007}

Track execution counts of the continuations of block structures (e.g.
IfStatements) to capture cases in which execution does not continue after a
block. For example:

for (;;) {
  return;
}
// Never reached, tracked by continuation counter.

A continuation counter only has a start position; it's range is implicitly
until the next sibling range or the end of the parent range.

Bug: v8:6000
Change-Id: I8e8f1f5b140b64c86754b916e626eb50f0707d70
Reviewed-on: https://chromium-review.googlesource.com/530846
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Marja Hölttä <marja@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46006}

If we pass in thin-string into a keyed load, the underlying internalized string is used to find the handler. However, the thin string itself was used to interpret the handler. Since the thin string itself isn't unique, this caused existing properties on the prototype chain to not be found in case of dictionary-mode prototypes.

Bug: chromium:731193
Change-Id: Ic98d3789ecf9175e17d9c898ab13231aad59efcc
Reviewed-on: https://chromium-review.googlesource.com/539596Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46005}

Bug: v8:6494
Change-Id: Ie6f91c3bad38e467dd047f4d2848473cc4085c2a
Reviewed-on: https://chromium-review.googlesource.com/536397
Commit-Queue: Loo Rong Jie <loorongjie@gmail.com>
Reviewed-by: Jochen Eisinger <jochen@chromium.org>
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46004}

It might happen that we deprecate the map of previous sub-literals if we create
literals with the same map several times. This is usually the case for
configuration arrays.

Bug: chromium:734051
Change-Id: I82284e5aae632286135b2092816d776d229c65af
Reviewed-on: https://chromium-review.googlesource.com/538665Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Commit-Queue: Camillo Bruni <cbruni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46003}

Bug: v8:6474
Change-Id: Ia20250d74c94bf2568ad044795188db583b7f36c
Reviewed-on: https://chromium-review.googlesource.com/539555Reviewed-by: Peter Marshall <petermarshall@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46002}

Here we optimize Dsubu by instead of loading imm and subtracting, we
load -imm and perform addition when loading -imm takes less instructions
than loading imm. Similarily li is optimized by loading -imm and
performing addition or loading ~imm and inverting bits using nor when
one of these loads takes two instructions less than loading imm, saving
at least one instruction. Tests are adjusted to cover these
optimizations.

BUG=
TEST=cctest/test-assembler-mips/li_macro
     cctest/test-assembler-mips/Dsubu

Review-Url: https://codereview.chromium.org/2909913002
Cr-Commit-Position: refs/heads/master@{#46001}

Mechanical change to remove argument adaption (should be a tad faster
this way). Especially next is called without arguments in the common
case.

Bug: v8:6354, v8:6369
Change-Id: I4180caabfc4c1bbf1a10a881dcbcd41e03614b27
Reviewed-on: https://chromium-review.googlesource.com/535453
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Caitlin Potter <caitp@igalia.com>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46000}

Large allocations would fail due to the flag not being set.

Bug: chromium:732836
Change-Id: I31686e382386a2d08582c86b29dc8f89841040d1
Reviewed-on: https://chromium-review.googlesource.com/535563Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Commit-Queue: Peter Marshall <petermarshall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45999}

Minor differences in how we dispatch on the regexp type
(IRREGEXP,ATOM,NOT_COMPILED) make significant differences in benchmark
performance. A simple switch turns out to be the best alternative.

BUG=chromium:734035, v8:6462

Change-Id: I09c613658e828b9fd1e3082624ef692b8b4a0c5f
Reviewed-on: https://chromium-review.googlesource.com/539295Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45998}