When preparsing top-level functions in a module, we didn't track
unresolved variables. Consequently, "this" ended up referencing
the global "this", which has the wrong value (in a module "this"
is supposed to be the undefined value).
This patch fixes that. This also lets us stop forcing context
allocation of all variables in module scopes, which the patch
takes care of as well.
Bug: chromium:791334
Change-Id: Ifac1f1adc033f3facfb3d29dd4bca32ee27bffcf
Reviewed-on: https://chromium-review.googlesource.com/808938
Reviewed-by: Marja Hölttä <marja@chromium.org>
Reviewed-by: Adam Klein <adamk@chromium.org>
Reviewed-by: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
Commit-Queue: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#50025}
Some refactor moved from
https://chromium-review.googlesource.com/c/v8/v8/+/798331.
Bug: v8:6917
Change-Id: I8cae6cfca7a0d7d8e234052c0ab0bfe252355e60
Reviewed-on: https://chromium-review.googlesource.com/819550
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Reviewed-by: Sergiy Byelozyorov <sergiyb@chromium.org>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#50020}
This reverts commit 1e49864fa7.
Reason for revert: Crashing test on the waterfall https://logs.chromium.org/v/?s=chromium%2Fbb%2Fclient.v8%2FV8_Linux_gcc_4.8%2F16871%2F%2B%2Frecipes%2Fsteps%2FCheck%2F0%2Flogs%2FReturnMultipleRandom%2F0
Original change's description:
> [turbofan] Implement on-stack returns (Intel)
>
> Add the ability to return (multiple) return values on the stack:
>
> - Extend stack frames with a new buffer region for return slots.
> This region is located at the end of a caller's frame such that
> its slots can be indexed as caller frame slots in a callee
> (located beyond its parameters) and assigned return values.
> - Adjust stack frame constructon and deconstruction accordingly.
> - Extend linkage computation to support register plus stack returns.
> - Reserve return slots in caller frame when respective calls occur.
> - Introduce and generate architecture instructions ('peek') for
> reading back results from return slots in the caller.
> - Aggressive tests.
> - Some minor clean-up.
>
> So far, only ia32 and x64 are implemented.
>
> Change-Id: I9532ad13aa307c1dec40548c5b84600fe2f762ce
> Reviewed-on: https://chromium-review.googlesource.com/766371
> Commit-Queue: Andreas Haas <ahaas@chromium.org>
> Reviewed-by: Ben Titzer <titzer@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#49994}
TBR=titzer@chromium.org,rossberg@chromium.org,ahaas@chromium.org
Change-Id: Ib257e92448942f8ef07d5ef246f9381f4784f014
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/819637
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Commit-Queue: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/master@{#50000}
Add the ability to return (multiple) return values on the stack:
- Extend stack frames with a new buffer region for return slots.
This region is located at the end of a caller's frame such that
its slots can be indexed as caller frame slots in a callee
(located beyond its parameters) and assigned return values.
- Adjust stack frame constructon and deconstruction accordingly.
- Extend linkage computation to support register plus stack returns.
- Reserve return slots in caller frame when respective calls occur.
- Introduce and generate architecture instructions ('peek') for
reading back results from return slots in the caller.
- Aggressive tests.
- Some minor clean-up.
So far, only ia32 and x64 are implemented.
Change-Id: I9532ad13aa307c1dec40548c5b84600fe2f762ce
Reviewed-on: https://chromium-review.googlesource.com/766371
Commit-Queue: Andreas Haas <ahaas@chromium.org>
Reviewed-by: Ben Titzer <titzer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49994}
Moving a register to itself is not only unnecessary overhead, it also
breaks invariants in the StackTransferRecipe.
R=ahaas@chromium.org
Bug: v8:6600, chromium:793551
Change-Id: I659fd66b4f2d4564c437ed9fb048322af4299d97
Reviewed-on: https://chromium-review.googlesource.com/819231
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49992}
This relands commit e71b802279.
This can now back in as the fix for chromium:787301 had enough time to
be tested in Canary.
Original change's description:
> [deoptimizer] Staged materialization of objects.
>
> The existing object materialization in the deoptimizer has the following problems:
>
> - Objects do not necessarily verify during materialization (because during the
> depth first walk we might have inconsistent objects).
>
> - Stack can overflow (because we just materialize using recursive calls).
>
> - We generalize object fields.
>
>
> This CL re-implements the materialization algorithm to solve this problem. The
> new implementation creates the objects in two steps:
>
> 1. We allocate space for all the objects. In general, we allocate ByteArrays
> of the right size. For leaf objects that cannot participate in cycles,
> we build and initialize the materialized objects completely.
>
> For JS objects, we insert markers into the byte array at the positions
> where unboxed doubles are expected.
>
> 2. We initialize all the objects with the proper field values and change the
> map from the ByteArray map to the correct map. This requires some sync
> with the concurrent marker (Heap::NotifyObjectLayoutChange).
>
> When initializing the JS object fields, we make sure that we respect
> the unboxed double marker.
>
> Bug: chromium:770106, v8:3836
> Change-Id: I1ec466a9d19db9538df4ba915516d4c3ca825632
> Reviewed-on: https://chromium-review.googlesource.com/777559
> Commit-Queue: Jaroslav Sevcik <jarin@chromium.org>
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#49821}
Bug: chromium:770106, v8:3836
Change-Id: Ied6c4e0fbae52713e55ae6dc13794a7521dbb8a5
Reviewed-on: https://chromium-review.googlesource.com/817745
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49982}
This moves the verify-predictable logic from the test runner into
a python wrapper script.
This revealed two more tests that don't print allocations, which are
now skipped.
Bug: v8:7166, v8:7177
Change-Id: Ie4a541cb2a20900414ffe1caf4b3fccc4a5edb52
Reviewed-on: https://chromium-review.googlesource.com/808971
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Reviewed-by: Sergiy Byelozyorov <sergiyb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49964}
Bug: chromium:780819
Change-Id: I07c5ff3cf955edb087a175ea2d71a35e0f520ec3
Reviewed-on: https://chromium-review.googlesource.com/813839
Commit-Queue: Georg Neis <neis@chromium.org>
Reviewed-by: Adam Klein <adamk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49953}
This reverts commit 59f221740c.
Reason for revert: android build issue (https://build.chromium.org/p/client.v8.fyi/builders/Android%20Release%20%28Nexus%205X%29/builds/3583)
Original change's description:
> [wasm] Fix wasm-to-wasm handling in 'native heap' lazy compile
>
> Wasm-to-wasm uses a tail call mechanism to reach the target
> function. This means there is no frame for it. This CL ports
> the fix for that for the WasmCodeManager case, akin the current
> fix for the GC case.
>
> Bug: v8:7140
> Change-Id: I04c8a8da1de9cb837a0423493216d2226c53e756
> Reviewed-on: https://chromium-review.googlesource.com/814498
> Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
> Reviewed-by: Ben Titzer <titzer@chromium.org>
> Commit-Queue: Mircea Trofin <mtrofin@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#49942}
TBR=bradnelson@chromium.org,titzer@chromium.org,mtrofin@chromium.org,clemensh@chromium.org
Change-Id: Iae0e43b386f08d2d56aeef70e9fa0af141232023
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:7140
Reviewed-on: https://chromium-review.googlesource.com/815180
Reviewed-by: Mircea Trofin <mtrofin@chromium.org>
Commit-Queue: Mircea Trofin <mtrofin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49943}
Wasm-to-wasm uses a tail call mechanism to reach the target
function. This means there is no frame for it. This CL ports
the fix for that for the WasmCodeManager case, akin the current
fix for the GC case.
Bug: v8:7140
Change-Id: I04c8a8da1de9cb837a0423493216d2226c53e756
Reviewed-on: https://chromium-review.googlesource.com/814498
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Ben Titzer <titzer@chromium.org>
Commit-Queue: Mircea Trofin <mtrofin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49942}
When enabling any coverage mode (other than best-effort), we trigger
deoptimization of all functions on the heap.
Prior to the recent removal of the weak list of optimized functions [0],
we'd unlink optimized code from all relevant JSFunctions during the call
to DeoptimizeAll.
After the weak-list-removal, this was no longer the case, hence this [1]
change which attempts to reset the code object from the
SharedFunctionInfo for all found JSFunction objects.
But this can create a situation in which JSFunctions are set up
incorrectly s.t. they have unoptimized code but no feedback vector.
This CL fixes that by leaving JSFunction objects untouched and relying
on self-healing mechanisms (CompileLazyDeoptimizedCode) to fix up
JSFunction::code.
[0] https://crrev.com/f0acede9bb05155c25ee87e81b4b587e8a76f690
[1] https://crrev.com/c/647596/5/src/debug/debug-coverage.cc
Bug: chromium:786784, chromium:791940, v8:6637
Change-Id: I13191f4c8800a0d72894b959105189dc09ca693e
Reviewed-on: https://chromium-review.googlesource.com/813615
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49932}
Ensure that the type is always stored correctly.
R=titzer@chromium.org
Bug: v8:6600, chromium:791810
Change-Id: Id3a3c20b14f8730b9550c548dec49ac47121e691
Reviewed-on: https://chromium-review.googlesource.com/811188
Reviewed-by: Ben Titzer <titzer@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49924}
Exposing the existing Context::AllowCodeGenerationFromStrings(false) API
to the command line.
Bug: v8:7134
Change-Id: I062ccff0b03c5bcf6878c41c455c0ded37a1d743
Reviewed-on: https://chromium-review.googlesource.com/809631
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49911}
- When a global object changes, invalidate its validity cell.
- The global object prototypes don't need to be gathered into an array in InitPrototypeChecks.
Bug: v8:7159
Change-Id: I3621c914d08b83e49e8a391800a92eb53ba19feb
Reviewed-on: https://chromium-review.googlesource.com/808588
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49901}
We cannot remove a speculative operation when it's type relies on it to deopt.
Fix this by only relying on the lowering to remove operations.
Bug: chromium:786521
Change-Id: I2cf45e8d45b76cfeb06e6329f323cade74719124
Reviewed-on: https://chromium-review.googlesource.com/793043
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49882}
For "top digit" (of the result) comparison to be applicable, we must
also check that there are no further digits in the source.
The included regression test flushes out another bug in "TruncateToNBits",
so that gets fixed here too (in contrast to the first landing attempt).
This reverts commit cb9e7af4e5.
Bug: v8:7150
Change-Id: Id631b1ae79e60b8e85ed4667e246a64c46765f2b
Reviewed-on: https://chromium-review.googlesource.com/807348
Reviewed-by: Georg Neis <neis@chromium.org>
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49877}
The proper fix would be to make TruncatingUseInfoFromRepresentation
respect tagged signed use representation, but requires extra work
to refine typing for all values that are stored into Smi fields.
Bug: chromium:791245
Change-Id: I83965bcc18a836d2c758a6a8b1477a4aa2c6133d
Reviewed-on: https://chromium-review.googlesource.com/808866
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Jaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49870}
- When a dictionary mode prototype changes, invalidate the validity cell.
- The dictionary mode prototypes don't need to be gathered into an array in InitPrototypeChecks.
Bug: v8:7159
Change-Id: I1c7bbaf4b20556f44df18be1463d38fa4fbabe05
Reviewed-on: https://chromium-review.googlesource.com/793732
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49857}
This unblocks the checks in the SimplifiedLowering that whenever we
store something as TaggedSigned, the input type should at least be
Type::SignedSmall.
Bug: chromium:791245
Change-Id: Ice6e55c2c6584c0ff60c1e033ba755c8863af32a
Reviewed-on: https://chromium-review.googlesource.com/808104
Commit-Queue: Jaroslav Sevcik <jarin@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49856}
- Removes JS implementation and InnerArrayFind/InnerArrayFindIndex
- Adds TFJ, with TFS for slow continuation path
Some quick benchmarks show ~2x improvement for unoptimized code
and up to 16% improvement against optimized code (diminishes with
larger arrays as iterating dominates).
https://github.com/peterwmwong/v8-perf/blob/master/array-find-findIndex/README.md
Bug: chromium:791045, v8:1956, v8:5049, v8:7165
Change-Id: Ie16252ed495bbd91fe548b16d5ef6764de791a50
Reviewed-on: https://chromium-review.googlesource.com/804704
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49851}
Eventually, we want to fix this also for tagged pointers (tracking bug: https://crbug.com/v8/7162).
Bug: chromium:791245
Change-Id: I93d6deff36cedcc9a4665fab0abe6fffdae9b61b
Reviewed-on: https://chromium-review.googlesource.com/806457
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Jaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49850}
This reverts commit e110b59cc7.
Reason for revert: Breaks arm debug on chromebook hardware:
https://build.chromium.org/p/client.v8.ports/builders/V8%20Arm%20-%20debug/builds/5335
Original change's description:
> [bigint] Fix early-return in asIntN
>
> For "top digit" (of the result) comparison to be applicable, we must
> also check that there are no further digits in the source.
>
> Bug: v8:7150
> Change-Id: I6ad317f6f600e11fef59b9907da1055e5586a3a8
> Reviewed-on: https://chromium-review.googlesource.com/804639
> Reviewed-by: Georg Neis <neis@chromium.org>
> Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#49846}
TBR=jkummerow@chromium.org,neis@chromium.org
Change-Id: I5dae82696d3ecb9602f73a2ff4760ed7bbcef1c5
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:7150
Reviewed-on: https://chromium-review.googlesource.com/806838
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49847}
For "top digit" (of the result) comparison to be applicable, we must
also check that there are no further digits in the source.
Bug: v8:7150
Change-Id: I6ad317f6f600e11fef59b9907da1055e5586a3a8
Reviewed-on: https://chromium-review.googlesource.com/804639
Reviewed-by: Georg Neis <neis@chromium.org>
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49846}
- Implement RunMicrotasks in CSA to prevent a potentially large number
of jumps between C++ and JS code while consuming te queue. Appears to
provide a ~60% speedup in microtask-heavy code, which from limited
testing appears to scale linearly.
The code-stub microtask pump bails out to the old C++ microtask pump
if it encounters a CallHandlerInfo microtask, and remains in C++ for
the remainder of the queue (returning to the JS/stub implementation
after the bailed out queue is exhausted).
- Add a variation of JSEntryStub which enters the new RunMicrotasks code
stub.
- Add a new RunMicrotasks helper to Execution, which uses the
RunMicrotasks entry stub.
Bug:
Change-Id: I4667d4dd633d24455ea5d7cef239da0af1a7365e
Reviewed-on: https://chromium-review.googlesource.com/650486
Commit-Queue: Caitlin Potter <caitp@igalia.com>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49842}
This reverts commit e71b802279.
Reason for revert: Need to have a back-mergeable fix.
Original change's description:
> [deoptimizer] Staged materialization of objects.
>
> The existing object materialization in the deoptimizer has the following problems:
>
> - Objects do not necessarily verify during materialization (because during the
> depth first walk we might have inconsistent objects).
>
> - Stack can overflow (because we just materialize using recursive calls).
>
> - We generalize object fields.
>
>
> This CL re-implements the materialization algorithm to solve this problem. The
> new implementation creates the objects in two steps:
>
> 1. We allocate space for all the objects. In general, we allocate ByteArrays
> of the right size. For leaf objects that cannot participate in cycles,
> we build and initialize the materialized objects completely.
>
> For JS objects, we insert markers into the byte array at the positions
> where unboxed doubles are expected.
>
> 2. We initialize all the objects with the proper field values and change the
> map from the ByteArray map to the correct map. This requires some sync
> with the concurrent marker (Heap::NotifyObjectLayoutChange).
>
> When initializing the JS object fields, we make sure that we respect
> the unboxed double marker.
>
> Bug: chromium:770106, v8:3836
> Change-Id: I1ec466a9d19db9538df4ba915516d4c3ca825632
> Reviewed-on: https://chromium-review.googlesource.com/777559
> Commit-Queue: Jaroslav Sevcik <jarin@chromium.org>
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#49821}
TBR=ulan@chromium.org,mstarzinger@chromium.org,jarin@chromium.org
Change-Id: I0657fb75330700dd7883c600dacb25676ebb47f9
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: chromium:770106, v8:3836
Reviewed-on: https://chromium-review.googlesource.com/806160
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Jaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49834}
The existing object materialization in the deoptimizer has the following problems:
- Objects do not necessarily verify during materialization (because during the
depth first walk we might have inconsistent objects).
- Stack can overflow (because we just materialize using recursive calls).
- We generalize object fields.
This CL re-implements the materialization algorithm to solve this problem. The
new implementation creates the objects in two steps:
1. We allocate space for all the objects. In general, we allocate ByteArrays
of the right size. For leaf objects that cannot participate in cycles,
we build and initialize the materialized objects completely.
For JS objects, we insert markers into the byte array at the positions
where unboxed doubles are expected.
2. We initialize all the objects with the proper field values and change the
map from the ByteArray map to the correct map. This requires some sync
with the concurrent marker (Heap::NotifyObjectLayoutChange).
When initializing the JS object fields, we make sure that we respect
the unboxed double marker.
Bug: chromium:770106, v8:3836
Change-Id: I1ec466a9d19db9538df4ba915516d4c3ca825632
Reviewed-on: https://chromium-review.googlesource.com/777559
Commit-Queue: Jaroslav Sevcik <jarin@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49821}
Since we have this d8 directory now, we can also use it.
R=machenbach@chromium.org
Bug: v8:7109
Change-Id: I595ceb30e1c9350ad00d5cfaf998e40294602103
Reviewed-on: https://chromium-review.googlesource.com/803214
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49817}
Flush the icache after JIT-ing using the WasmCodeManager. Also, re-enable
tests that were previously failing on Linux ARM.
Bug: v8:7138
Change-Id: I8e18b80dba58df173a2360f8ac365ee5daaf3239
Reviewed-on: https://chromium-review.googlesource.com/802961
Commit-Queue: Mircea Trofin <mtrofin@chromium.org>
Reviewed-by: Ben Titzer <titzer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49800}
Adds new API function to request code cache. Earlier code cache was
produced along with compile requests. This new API allows us to request
code cache after executing. Also adds support in the code serializer to
serialize after executing the script.
Bug: chromium:783124,chromium:789694
Cq-Include-Trybots: master.tryserver.chromium.linux:linux_chromium_rel_ng
Change-Id: Id4e6a967e176e3e979dc4ccb9a37a353c70c3890
Reviewed-on: https://chromium-review.googlesource.com/797036
Reviewed-by: Yang Guo <yangguo@chromium.org>
Commit-Queue: Mythri Alle <mythria@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49793}
These now pass even when forcing optimization.
TBR=jkummerow@chromium.org
Bug: v8:6791
Change-Id: I4d7c7d37b48e6e970d33474fa7fd637e34b0bda0
Reviewed-on: https://chromium-review.googlesource.com/803374
Reviewed-by: Georg Neis <neis@chromium.org>
Commit-Queue: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49781}
It reflects the semantics of ToBoolean, so it must be adapted for
bigints.
Bug: v8:6791
Change-Id: I18931df21528463dacf5ad50fa8264b1c968c6b5
Reviewed-on: https://chromium-review.googlesource.com/799831
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Commit-Queue: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49776}
This reverts commit e42e7fc800.
Reason for revert: Speculative revert for:
https://crbug.com/v8/7149
Original change's description:
> [objects] No longer create short external strings.
>
> This fixes String::MakeExternal() to bail out if the subject string
> doesn't fit a regular ExternalString, instead of creating a short
> external string. The observation here is that for short external strings
> the overhead of having to have the StringResource plus going to the
> runtime/C++ for each and every character access from JavaScript land
> is probably bigger than the anticipated benefits.
>
> If this turns out to be wrong and there's a real benefit, we should make
> use of ThinStrings instead of having a separate way to represent
> external strings.
>
> Bug: v8:6621, v8:7109, v8:7145
> Change-Id: I4b75da08b82a72027c782a69de9c8eaf3cca1d4d
> Reviewed-on: https://chromium-review.googlesource.com/799750
> Reviewed-by: Yang Guo <yangguo@chromium.org>
> Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#49735}
TBR=yangguo@chromium.org,bmeurer@chromium.org
Change-Id: I3f5cfa9ab5c99ddce1d61ede9ed9515cb3936cdd
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:6621, v8:7109, v8:7145, v8:7149
Reviewed-on: https://chromium-review.googlesource.com/801675
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49770}
