We introduce a new information type ForwardingIndex to be stored in
the Name::Hash field (to be used in the future).
To do so we use the 2 least significant bit to distinguish types
of information stored in the hash field (in contrast to only bit 1
to distinguis integer indicies from "real" hashes).
This motivated a refactor to use base::BitField for the hash field.

Bug: v8:12007
Change-Id: I651c86807edfc218792d0db12379374eaa50c930
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3432385Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Commit-Queue: Patrick Thier <pthier@chromium.org>
Cr-Commit-Position: refs/heads/main@{#78975}

Avoid repeated collisions when the name doesn't hold much entropy.
This is typically the case with minified sources where 1 or 2 letter
names are used very frequently.

Bug: v8:12316
Change-Id: I20df3a6b0c5daf7975668d25404eca94a1230fe0
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3222759Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/main@{#77416}

Bug: v8:11074
Change-Id: I108a847e12df2438cc73e4f7a31ba4148f07cdc0
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2569562
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#71593}

By replacing usage of the IsNotArrayIndex bit with IsNotIntegerIndex,
we get back one bit that we can use to increase the number of hash bits
stored. The price is that strings that represent array/integer indices
beyond the cacheable range will have to be scanned more often, but these
strings should be rare, and we expect that the additional hash bit is
more worthwhile to have.

Bug: v8:9904
Change-Id: I33f74b0a73f4754aee85805d4b7c409177668439
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2051947Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
Auto-Submit: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#66299}

This is useful for the upcoming "huge TypedArrays" support, to be able
to quickly decide in stubs/generated code whether a string used as the
key for a property load/store can possibly be an exotic integer index.

Bug: v8:4153
Change-Id: I50ce655d2f78fb36e5615fd580f22c9290216c84
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1821460
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#64165}

The stub cache doubles in size when switching to 64-bit. The references
stored in it are not currently compressed even with ptr-compr enabled.

This patch compresses those references so the table is the same size on
32- and 64-bit architectures, which is beneficial on benchmarks which
utilise the stub cache heavily.

Reducing the stub cache size has lead to an improvement of 0.7% in
runs/minute being observed on Speedometer on a Pixel device, and 0.4% on
a Pixel3 device.

Also add constructors to [Strong]TaggedValue to support compression.

Cq-Include-Trybots: luci.v8.try:v8_linux64_pointer_compression_rel_ng
Cq-Include-Trybots: luci.v8.try:v8_linux64_arm64_pointer_compression_rel_ng
Change-Id: I3b643d674356deaa129588189df7adfc91d15db4
Bug: v8:7703
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1635694
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Santiago Aboy Solanes <solanes@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62308}

Bug: v8:9020

Change-Id: Ie624a02598f5c3a43e40e03d0337c17ca5cc3769
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1541052
Commit-Queue: Sigurd Schneider <sigurds@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#60628}

This should recover the regression from constant field tracking
in Speedometer/angular.

Bug: chromium:930680
Change-Id: I9ccbcbdaf11556596ed5df5c08829b7ae329cab7
Reviewed-on: https://chromium-review.googlesource.com/c/1480383Reviewed-by: Igor Sheludko <ishell@chromium.org>
Commit-Queue: Jaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59775}

Bug: v8:3770
Change-Id: I4da6404aa968adca1fbb49029fc304622101d6c3
Reviewed-on: https://chromium-review.googlesource.com/c/1349112
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#57853}

Bug: v8:3770
Change-Id: I52660eeda1bd299953793af9af1395f47e89072e
Reviewed-on: https://chromium-review.googlesource.com/c/1331155
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#57454}

This CL applies the equivalent of the Object -> ObjectPtr
transformation to MaybeObject and HeapObjectReference. We
need no renaming in this case because we can just migrate
them both in one go.

Bug: v8:3770
Change-Id: Ie1259c3e8c556eff00f8bcf534d7270ca9fe00e1
Reviewed-on: https://chromium-review.googlesource.com/c/1298386
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#57010}

Drive-by: Eliminate unnecessary includes to src/assembler.h.

Bug: v8:8238
Change-Id: Ia0408b993b8b1c21a76c947f406f96b63fe41994
Reviewed-on: https://chromium-review.googlesource.com/c/1288810Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Sigurd Schneider <sigurds@chromium.org>
Cr-Commit-Position: refs/heads/master@{#56817}

Since the StubCache it's cleared at the end of the GC, it doesn't
matter if it contains weak or strong pointers.

BUG=v8:7308

Change-Id: Ib141e3d411523c67ccb8f8979845a88488d6e4ee
Reviewed-on: https://chromium-review.googlesource.com/1064053
Commit-Queue: Marja Hölttä <marja@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53311}

This check verifies that all .h files in the src/ directory have an
include guard of the form

 #ifndef V8_PATH_TO_FILE_H_
 #define V8_PATH_TO_FILE_H_
 // ...
 #endif  // V8_PATH_TO_FILE_H_

The check can be skipped with a magic comment:

 // PRESUBMIT_INTENTIONALLY_MISSING_INCLUDE_GUARD

Cq-Include-Trybots: luci.v8.try:v8_linux_noi18n_rel_ng;master.tryserver.blink:linux_trusty_blink_rel
Change-Id: I0a7b96abec289ad60f64ba8418f1892a6969596d
Reviewed-on: https://chromium-review.googlesource.com/897487Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51079}

This xor can never change the number of collisions, so it should be safe to remove.

Bug: 
Change-Id: I253c0ece422f66e7cba15b13c041cfb6c8361674
Reviewed-on: https://chromium-review.googlesource.com/809113Reviewed-by: Igor Sheludko <ishell@chromium.org>
Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49985}

Bug: 
Change-Id: I41d3f3086f5e90a1a1579c18eca59b5d098f637f
Reviewed-on: https://chromium-review.googlesource.com/690374
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48207}

R=ishell@chromium.org

Change-Id: I3e69c94d43d4db7255ec46f94c43f1411795ca9d
Reviewed-on: https://chromium-review.googlesource.com/666957Reviewed-by: Igor Sheludko <ishell@chromium.org>
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48016}

Tbr: jkummerow@chromium.org
Bug: v8:6408
Change-Id: I23c420c5b88bcee06e381f27eb7fe59976d3bba6
Reviewed-on: https://chromium-review.googlesource.com/644716
Commit-Queue: Adam Klein <adamk@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#47752}

Change-Id: I20ed35a7fb5104a9cc66bb54fa8966589c43d7f9
Reviewed-on: https://chromium-review.googlesource.com/507287Reviewed-by: Andreas Haas <ahaas@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Daniel Clifford <danno@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Marja Hölttä <marja@chromium.org>
Reviewed-by: Jochen Eisinger <jochen@chromium.org>
Commit-Queue: Wiktor Garbacz <wiktorg@google.com>
Cr-Commit-Position: refs/heads/master@{#45458}

... and stop checking that the native contexts of maps recorded in feedback vector
match function's native context - the feedback vector machinery already guarantees
that.

BUG=v8:6325

Change-Id: Iacd3f3a5f703694ff57b774b9658e186ad66641b
Reviewed-on: https://chromium-review.googlesource.com/490084Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#44982}

BUG=

Review-Url: https://codereview.chromium.org/2710513003
Cr-Commit-Position: refs/heads/master@{#43329}

The handwritten-assembly implementations of both dispatcher and
generic stub have been replaced by Turbofan-generated stubs.

Review-Url: https://codereview.chromium.org/2523473002
Cr-Commit-Position: refs/heads/master@{#41188}

BUG=

Review-Url: https://codereview.chromium.org/2412043003
Cr-Commit-Position: refs/heads/master@{#40255}

Rebuilding (after touching certain files) is crazy slow because
includes are out of control.

The (last remaining) offending include path is: ast.h <- liveedit.h <-
debug.h <- src/x64/assembler-whatever-port-inl.h <-
src/macro-assembler.h <- everything possible

With this CL, the rebuild steps needed when touching ast-value-factory.h
drops from 365 to 181.

BUG=v8:5294
TBR=bmeurer@chromium.org

Review-Url: https://codereview.chromium.org/2316443002
Cr-Commit-Position: refs/heads/master@{#39195}

BUG=chromium:618701

Review-Url: https://codereview.chromium.org/2167493003
Cr-Commit-Position: refs/heads/master@{#37946}

Revert of [ic] [stubs] Don't use Code::flags in megamorphic stub cache hash computations. (patchset #2 id:20001 of https://codereview.chromium.org/2147433002/ )

Reason for revert:
Unfortunately, the performance issues are still there on Android.

Original issue's description:
> [ic] [stubs] Don't use Code::flags in megamorphic stub cache hash computations.
>
> This should avoid weird performance issues when changing layout of Code::flags field.
>
> BUG=chromium:618701
>
> Committed: https://crrev.com/aa4140b1ccc114b82700471513c715f68b7c5dac
> Cr-Commit-Position: refs/heads/master@{#37755}

TBR=jkummerow@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=chromium:618701

Review-Url: https://codereview.chromium.org/2147213004
Cr-Commit-Position: refs/heads/master@{#37801}

This should avoid weird performance issues when changing layout of Code::flags field.

BUG=chromium:618701

Review-Url: https://codereview.chromium.org/2147433002
Cr-Commit-Position: refs/heads/master@{#37755}

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}

[stubs] Introducing LoadICTFStub and LoadICTrampolineTFStub and a switch to enable them instead of respective platform stubs.

The stubs do not increase respective counters as they are in the snapshot and --native-code-counters is off during snapshot creation anyway.

Review-Url: https://codereview.chromium.org/2031753003
Cr-Commit-Position: refs/heads/master@{#36754}

This enables linter checking for "readability/namespace" violations
during presubmit and instead marks the few known exceptions that we
allow explicitly.

R=bmeurer@chromium.org

Review URL: https://codereview.chromium.org/1371083003

Cr-Commit-Position: refs/heads/master@{#31019}

BUG=

Review URL: https://codereview.chromium.org/1299213002

Cr-Commit-Position: refs/heads/master@{#30250}

This patch finally allows running and passing tests with vector-based
Load and KeyedLoad ICs.

BUG=
R=jkummerow@chromium.org

Review URL: https://codereview.chromium.org/767743002

Cr-Commit-Position: refs/heads/master@{#25800}

the megamorphic load case in hydrogen. A simple approach is to
wrap the probe activity in a hydrogen instruction.

The instruction is novel in that it always tail-calls away.

R=yangguo@chromium.org

Review URL: https://codereview.chromium.org/535873002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@23772 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

BUG=
R=bmeurer@chromium.org

Review URL: https://codereview.chromium.org/483683005

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@23306 ce2b1a6d-e550-0410-aec6-3dcde31c8c00