Commit Graph

83 Commits

Author SHA1 Message Date
Santiago Aboy Solanes
31ec4d4456 [ptr-compr] Add a flag to to enable/disable the old system
The plan is to eliminate the DecompressionElimination reducer
as well as the Compressed representation. We are adding a flag to
easily swap between the old system and the new one.

Bug: v8:7703, v8:9206
Change-Id: I083fc7a835962eddfd60e9c403131587489f4632
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1815134
Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#64185}
2019-10-09 12:18:47 +00:00
Tobias Tebbi
afd83c074f [csa] move TNode to separate header
This enables using TNode types without including code-assembler.h,
which is useful when generating CallInterfaceDescriptors.

As a drive-by, this moves TNode from v8::internal::compiler to
v8::internal. It's only used outside of the compiler anyway.

Change-Id: I3d938c22366a3570315041683094f77b0d1096a2
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1798425
Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
Reviewed-by: Michael Stanton <mvstanton@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63721}
2019-09-12 14:48:03 +00:00
Santiago Aboy Solanes
48de043bb7 [CSA] TNodified methods related to call and construct
Also TNodified context in interpreter-intrinsics-generator.cc

Bug: v8:6949
Change-Id: Ia5d5b4dd61aa83592f1c7e1b502f34504cb25dbd
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1784918
Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
Reviewed-by: Mythri Alle <mythria@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63615}
2019-09-09 12:34:12 +00:00
Santiago Aboy Solanes
ff24879ae8 [CSA] TNodify dispatch, RegisterFile and context methods
TNodified:
 * code-assembler
   * TailCallBytecodeDispatch
 * interpreter-assembler
   * GetContextAtDepth
   * ExportParametersAndRegisterFile
   * ImportRegisterFile
   * Dispatch
   * DispatchToBytecode
   * DispatchToBytecodeHandlerEntry
   * DispatchWide
   * return type of Jump (Jumps are coming in another CL)
   * LoadBytecode

Removed DispatchToBytecodeHandler since it was unused.
Removed target_bytecode parameter of DispatchToBytecodeHandlerEntry
since it was unused.

Bug: v8:6949
Change-Id: Icd3ded28cc1fd1dc528219dd83cf646e67c9b878
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1782838
Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63577}
2019-09-05 13:34:39 +00:00
Santiago Aboy Solanes
f56b923665 [CSA] TNodify Bytecode operands and constant pool loading
TNodified from interpreter-generator:
 * SwitchOnSmiNoFeedback
 * CreateFunctionContext
 * CreateEvalContext
 * SwitchOnGeneratorState
since they were using some of the interpreter-assembler now TNodified
methods.

Bug: v8:6949
Change-Id: I0055100428232e8bdc79cb4356954bac52f4a30d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1781689
Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63576}
2019-09-05 12:14:59 +00:00
Leszek Swirski
0292896dbf [csa] Add TaggedEqual for comparing tagged values
Replace uses of WordEqual on two tagged representation nodes with a new
TaggedEqual helper, which on pointer compressed configs only compares
the bottom 32-bits of the word. We no longer allow using WordEqual on
anything not known to be a WordT (i.e. Node* or TNode<Object>).

In the future, this may allow us to ignore the top bits of an
uncompressed Smi, and have simpler decompression, though this patch is
not sufficient for such a change.

As a necessary drive-by, TNodify a bunch of stuff.

Bug: v8:8948
Change-Id: Ie11b70709e5d3073f12551b37b420a172a71bc99
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1763531
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Santiago Aboy Solanes <solanes@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63372}
2019-08-23 14:31:11 +00:00
Leszek Swirski
c4db8bf536 [cleanup] TNodify nodes which are set by a TNode function
Automated cleanup which finds patterns of `Node* a = foo` where `foo` is
a TNode expression, and replaces Node* with the appropriate TNode.

Bug: v8:9396
Change-Id: I8b0cd9baf10e74d6e2e336eae62eca6cfe6a9c11
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1762515
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Auto-Submit: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63335}
2019-08-22 10:30:16 +00:00
Santiago Aboy Solanes
007cbd2cfe Reland "[CSA][cleanup] TNodify some methods related to prototype and property lookup"
This is a reland of 82111e2286

Relanding since we now have more shards:
https://chromium-review.googlesource.com/c/v8/v8/+/1760810

Original change's description:
> [CSA][cleanup] TNodify some methods related to prototype and property lookup
>
> This is a CL in a string of CLs that aims to TNodify CSA. In particular,
> there were some loads that were done in AnyTagged instead of
> TaggedPointer. TNode-ifying them brings improvement in pointer
> compression since we are able to decompress using the Pointer
> decompression.
>
> TNodified:
>  * LoadJSFunctionPrototype
>  * TryPrototypeChainLookup
>  * OrdinaryHasInstance
>
> Also TNodified loads regarding:
>  * FeedbackCell::kValueOffset
>  * HeapObject::kMapOffset
>  * JSFunction::kSharedFunctionInfoOffset
>  * JSFunction::kFeedbackCellOffset
>  * Map::kInstanceTypeOffset
>  * Map::kInstanceDescriptorsOffset
>  * Map::kPrototypeOffset
>
> Drive-by cleanup: StoreJSArrayLength and StoreElements were unused.
>
> Bug: v8:6949, v8:9396
> Change-Id: I89697b5c02490906be1eee63cf3d9e60a1094d48
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1755844
> Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
> Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#63216}

Bug: v8:6949, v8:9396
Change-Id: I040aefcf8af60611f7b3c24f3bd5c661e03b6ada
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1760811
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63249}
2019-08-19 15:00:10 +00:00
Maya Lekova
3a7a4a2fe4 Revert "[CSA][cleanup] TNodify some methods related to prototype and property lookup"
This reverts commit 82111e2286.

Reason for revert: Speculative revert, could be causing timeouts - https://ci.chromium.org/p/v8/builders/ci/V8%20Linux%20-%20arm%20-%20sim%20-%20debug/17567

Original change's description:
> [CSA][cleanup] TNodify some methods related to prototype and property lookup
> 
> This is a CL in a string of CLs that aims to TNodify CSA. In particular,
> there were some loads that were done in AnyTagged instead of
> TaggedPointer. TNode-ifying them brings improvement in pointer
> compression since we are able to decompress using the Pointer
> decompression.
> 
> TNodified:
>  * LoadJSFunctionPrototype
>  * TryPrototypeChainLookup
>  * OrdinaryHasInstance
> 
> Also TNodified loads regarding:
>  * FeedbackCell::kValueOffset
>  * HeapObject::kMapOffset
>  * JSFunction::kSharedFunctionInfoOffset
>  * JSFunction::kFeedbackCellOffset
>  * Map::kInstanceTypeOffset
>  * Map::kInstanceDescriptorsOffset
>  * Map::kPrototypeOffset
> 
> Drive-by cleanup: StoreJSArrayLength and StoreElements were unused.
> 
> Bug: v8:6949, v8:9396
> Change-Id: I89697b5c02490906be1eee63cf3d9e60a1094d48
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1755844
> Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
> Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#63216}

TBR=rmcilroy@chromium.org,solanes@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: v8:6949, v8:9396
Change-Id: Ib6ae8fe86a598ed1066894595565e1162cf7dd1f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1758310
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Reviewed-by: Santiago Aboy Solanes <solanes@chromium.org>
Commit-Queue: Maya Lekova <mslekova@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63233}
2019-08-19 08:38:48 +00:00
Santiago Aboy Solanes
82111e2286 [CSA][cleanup] TNodify some methods related to prototype and property lookup
This is a CL in a string of CLs that aims to TNodify CSA. In particular,
there were some loads that were done in AnyTagged instead of
TaggedPointer. TNode-ifying them brings improvement in pointer
compression since we are able to decompress using the Pointer
decompression.

TNodified:
 * LoadJSFunctionPrototype
 * TryPrototypeChainLookup
 * OrdinaryHasInstance

Also TNodified loads regarding:
 * FeedbackCell::kValueOffset
 * HeapObject::kMapOffset
 * JSFunction::kSharedFunctionInfoOffset
 * JSFunction::kFeedbackCellOffset
 * Map::kInstanceTypeOffset
 * Map::kInstanceDescriptorsOffset
 * Map::kPrototypeOffset

Drive-by cleanup: StoreJSArrayLength and StoreElements were unused.

Bug: v8:6949, v8:9396
Change-Id: I89697b5c02490906be1eee63cf3d9e60a1094d48
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1755844
Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63216}
2019-08-15 16:07:16 +00:00
Georg Schmid
9681601bb8 Reland "[csa] Tweak CSA pipeline to eliminate more redundant checks"
This is a reland of a66e3e5744

Original change's description:
> [csa] Tweak CSA pipeline to eliminate more redundant checks
>
> - Lower LoadObjectField to LoadFromObject
> - Mark LoadFromObject and StoreToObject as non-allocating
> - Use optimizable BitcastTaggedSignedToWord in TaggedIsNotSmi check
>
> R=jarin@chromium.org, tebbi@chromium.org
>
> Change-Id: I42992d46597be795aee3702018f7efd93fcc6ebf
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1657926
> Commit-Queue: Georg Schmid <gsps@google.com>
> Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#62173}

R=tebbi@chromium.org

Change-Id: Id7ae13ba17a2083fd4109f34ce026030716ececb
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1660622
Commit-Queue: Georg Schmid <gsps@google.com>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62202}
2019-06-17 09:40:29 +00:00
Yang Guo
64daad8e7b Revert "[csa] Tweak CSA pipeline to eliminate more redundant checks"
This reverts commit a66e3e5744.

Reason for revert: Likely to have caused UBSAN issues: https://ci.chromium.org/p/v8/builders/ci/V8%20Linux64%20UBSan/6671

Original change's description:
> [csa] Tweak CSA pipeline to eliminate more redundant checks
> 
> - Lower LoadObjectField to LoadFromObject
> - Mark LoadFromObject and StoreToObject as non-allocating
> - Use optimizable BitcastTaggedSignedToWord in TaggedIsNotSmi check
> 
> R=​jarin@chromium.org, tebbi@chromium.org
> 
> Change-Id: I42992d46597be795aee3702018f7efd93fcc6ebf
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1657926
> Commit-Queue: Georg Schmid <gsps@google.com>
> Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#62173}

TBR=jarin@chromium.org,tebbi@chromium.org,gsps@google.com

Change-Id: I0a1c0515a8a61d32f77a392f1efc0751b6aae2a1
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1660485
Reviewed-by: Yang Guo <yangguo@chromium.org>
Commit-Queue: Yang Guo <yangguo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62179}
2019-06-14 12:44:23 +00:00
Georg Schmid
a66e3e5744 [csa] Tweak CSA pipeline to eliminate more redundant checks
- Lower LoadObjectField to LoadFromObject
- Mark LoadFromObject and StoreToObject as non-allocating
- Use optimizable BitcastTaggedSignedToWord in TaggedIsNotSmi check

R=jarin@chromium.org, tebbi@chromium.org

Change-Id: I42992d46597be795aee3702018f7efd93fcc6ebf
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1657926
Commit-Queue: Georg Schmid <gsps@google.com>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62173}
2019-06-14 11:38:48 +00:00
Yang Guo
a0c3797461 Move more relevant files to src/objects
TBR=bmeurer@chromium.org,leszeks@chromium.org

Bug: v8:9247
Change-Id: I8d14d0192ea8c705f8274e8e61a162531826edb6
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1624220
Reviewed-by: Yang Guo <yangguo@chromium.org>
Reviewed-by: Hannes Payer <hpayer@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61769}
2019-05-23 08:52:30 +00:00
Yang Guo
0fa243af70 Move relevant files to src/execution
Bug: v8:9247
Change-Id: I79e0553e8a0d6dac2aa16b94a6c0e05b6ccde4a1
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1621934
Commit-Queue: Yang Guo <yangguo@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61725}
2019-05-22 08:36:33 +00:00
Yang Guo
a6eeea35cb Move code generation related files to src/codegen
Bug: v8:9247

TBR=bmeurer@chromium.org,neis@chromium.org
NOPRESUBMIT=true

Change-Id: Ia1e49d1aac09c4ff9e05d58fab9d08dd71198878
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1621931
Reviewed-by: Yang Guo <yangguo@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Commit-Queue: Yang Guo <yangguo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61682}
2019-05-21 10:33:39 +00:00
Santiago Aboy Solanes
1d567568f6 [ptr-compr][csa] Loading CompressedXXX (+ Change node) instead of TaggedXXX
We translate loads with TaggedXXX (XXX in {"", "Signed", "Pointer"})
representation in CSA into loads of CompressedXXX +
ChangeCompressedXXXToTaggedXXX in the raw-machine-assembler.

This way, CSA doesn't need to know about Compressed values since we
are introducing an explicit "decompress" node.

Also updating tests that were checking for the load nodes.

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

Bug: v8:8977, v8:7703
Change-Id: Ie22ca8123a25ef005c1ff7383776f9355020fa42
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1565897
Reviewed-by: Michael Stanton <mvstanton@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
Cr-Commit-Position: refs/heads/master@{#60873}
2019-04-16 14:28:20 +00:00
Mythri
71c66873d6 [lite] Allocate FeedbackCell arrays for create closures in lite mode
We want to allocate feedback vectors lazily in lite mode. To do that,
we should create closures with the correct feedback cell. This cl
allocates feedback cell arrays to hold these feedback cells in lite mode.
This cl also modifies the compile lazy to builtin to expect these arrays
in the feedback cell.

Drive-by fix: InterpreterEntryTrampoline no longer has argument count in
a register. So updated comments and removed unnecessary push/pop of this
register.

Bug: v8:8394
Change-Id: I10d8ca67cebce61a284f0c80b200e1f0c24577a2
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1511274
Reviewed-by: Hannes Payer <hpayer@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Commit-Queue: Mythri Alle <mythria@chromium.org>
Cr-Commit-Position: refs/heads/master@{#60189}
2019-03-12 14:28:29 +00:00
Mythri
4e321413d8 Allocate feedback cells in an array decoupled from other slots
This is a pre-work for allocating feedback vectors lazily. Feedback cells
are required to share the feedback vectors across the different closures
of the same function. Currently, they are held in the CreateClosureSlot
in the feedback vector. With lazy feedback vector allocation, we may not
have a feedback vector. However, we still need a place to store the
feedback cells, so if feedback vector is allocated in future it can still
be shared across closures.

Here is the detailed design doc:
https://docs.google.com/document/d/1m2PTNChrlJqw9MiwK_xEJfqbFHAgEHmgGqmIN49PaBY/edit

BUG=v8:8394

Change-Id: Ib406d862b2809b1293bfecdcfcf8dea3127cb1c7
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1503753
Commit-Queue: Mythri Alle <mythria@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#60147}
2019-03-11 11:20:21 +00:00
Igor Sheludko
f70bb59b57 [ptr-compr] Prepare for changing kTaggedSize, pt.1
Includes various fixes and cleanups here and there.

Bug: v8:7703, v8:8852
Change-Id: I603eb0212cab3fecabfa15dceb70ee23b81cdb5a
Reviewed-on: https://chromium-review.googlesource.com/c/1491595
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59909}
2019-02-27 15:26:09 +00:00
Igor Sheludko
46d1986812 [cleanup] Fix kPointerSize in tests
Bug: v8:8477, v8:8834
Change-Id: I9213cca077a2758b87a6cb95bcb01d0186c32098
Reviewed-on: https://chromium-review.googlesource.com/c/1472633
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59602}
2019-02-14 15:29:52 +00:00
Igor Sheludko
93d92cfbbe [ptr-compr] Fix compressing stores in CSA/builtins
... and also loads of off-heap tagged values.

Bug: v8:7703
Change-Id: I0dd15ecda76cc35fe5f2f51a7103937a7ac238dc
Reviewed-on: https://chromium-review.googlesource.com/c/1459639
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59468}
2019-02-08 17:24:19 +00:00
Jakob Kummerow
c640296e5a [ubsan] Avoid signed left shifts
The workaround is simple: cast to unsigned before shifting.

Bug: v8:3770
Change-Id: I5f0f7af697ec5db0ab1df3d061008940c83c5c56
Reviewed-on: https://chromium-review.googlesource.com/c/1436215
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Deepti Gandluri <gdeepti@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59140}
2019-01-28 20:43:47 +00:00
Igor Sheludko
d7e6fbe5da Define return count and return types in CallInterfaceDescriptor.
Bug: v8:7754, v8:6600
Change-Id: I4db943d4a4a02a14bba670f89661ea98c5e306dd
Reviewed-on: https://chromium-review.googlesource.com/1107919
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53907}
2018-06-21 09:35:28 +00:00
Clemens Hammacher
3cb376dc83 Make CallInterfaceDescriptor isolate-independent
Currently each isolate stores its own array of
{CallInterfaceDescriptorData}. This array has size 173, and each entry
has 40 bytes. That's already 7kB per isolate.
Additionally, each {CallInterfaceDescriptorData} allocates two
heap-allocated arrays, which probably add up to more than the static
size of the {CallInterfaceDescriptorData}. Note that all the
{CallInterfaceDescriptorData} instances are initialized eagerly on
isolate creation.

Since {CallInterfaceDescriptor} is totally isolate independent itself,
this CL refactors the current design to avoid a copy of them per
isolate, and instead shares them process-wide. Still, we need to free
the allocated heap arrays when the last isolate dies to avoid leaks.
This can probably be refactored later by statically initializing more
and avoiding the heap allocations all together.

This refactoring will also allow us to use {CallInterfaceDescriptor}s
from wasm background compilation threads, which are not bound to any
isolate.

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

Bug: v8:6600
Change-Id: If8625b89951eec8fa8986b49a5c166e874a72494
Reviewed-on: https://chromium-review.googlesource.com/1100879
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53803}
2018-06-18 15:55:53 +00:00
Jaroslav Sevcik
f53dfd934d Replace array index masking with the poisoning approach.
The idea is to mark all the branches and loads participating in array
bounds checks, and let them contribute-to/use the poisoning register.
In the code, the marks for array indexing operations now contain
"Critical" in their name. By default (--untrusted-code-mitigations),
we only instrument the "critical" operations with poisoning.

With that in place, we also remove the array masking approach based
on arithmetic.

Since we do not propagate the poison through function calls,
we introduce a node for poisoning an index that is passed through
function call - the typical example is the bounds-checked index
that is passed to the CharCodeAt builtin.

Most of the code in this CL is threads through the three levels of
protection (safe, critical, unsafe) for loads, branches and flags.

Bug: chromium:798964

Change-Id: Ief68e2329528277b3ba9156115b2a6dcc540d52b
Reviewed-on: https://chromium-review.googlesource.com/995413
Commit-Queue: Jaroslav Sevcik <jarin@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52883}
2018-04-30 13:22:44 +00:00
Mythri
84c84fb36f Fix interpreter-assembler-unittest to check poisoning on unaligned loads
Check for poisoned loads in unaligned loads in
interpreter-assembler-unittest node matcher.

Change-Id: I5007ed1767edb035181c66028dda064b7792267f
Reviewed-on: https://chromium-review.googlesource.com/1018902
Reviewed-by: Miran Karić <miran.karic@mips.com>
Commit-Queue: Mythri Alle <mythria@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52700}
2018-04-20 07:20:01 +00:00
Tobias Tebbi
1ef6c4374e [turbofan] unify interpreter and JIT speculation poisoning
This CL changes the poisoning in the interpreter to use the
infrastructure used in the JIT.

This does not change the original flag semantics:

--branch-load-poisoning enables JIT mitigations as before.

--untrusted-code-mitigation enables the interpreter mitigations
  (now realized using the compiler back-end), but does not enable
  the back-end based mitigations for the Javascript JIT. So in effect
  --untrusted-code-mitigation makes the CSA pipeline for bytecode handlers
  use the same mechanics (including changed register allocation) that
  --branch-load-poisoning enables for the JIT.

Bug: chromium:798964
Cq-Include-Trybots: master.tryserver.blink:linux_trusty_blink_rel
Change-Id: If7f6852ae44e32e6e0ad508e9237f24dec7e5b27
Reviewed-on: https://chromium-review.googlesource.com/928881
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52243}
2018-03-27 12:55:28 +00:00
jgruber
3b99189b5d Add external references macro list
The macro list avoids duplication in external-reference-table and will
allow us to statically determine the size of the table in a follow-up.

TBR=mlippautz@chromium.org

Bug: v8:6666
Change-Id: I06bb2e8c25970b3c1047dafd6c63d7ca291fe37e
Reviewed-on: https://chromium-review.googlesource.com/956187
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Sathya Gunasekaran <gsathya@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51850}
2018-03-09 16:43:06 +00:00
Benedikt Meurer
aff1f3788b [cleanup] Introduce a dedicated FeedbackCell.
This is preparatory cleanup work for eventually tracking the functions
(rather than concrete closures) in the CALL_IC, also for builtins like
the default PromiseCapability [[Resolve]] and [[Reject]] functions. It
adds a new FeedbackCell type, which is used by JSFunctions consistently
now to reference the feedback vector (or undefined if not the function
is not compiled yet or is a native/asm.js function).

This also changes the calling convention for FastNewClosure builtin and
the JSCreateClosure operator in TurboFan to carry the FeedbackCell here
instead of the parent FeedbackVector and the slot index. In addition we
eliminate the now unused %InterpreterNewClosure runtime function.

Bug: v8:2206, v8:7253, v8:7310
Change-Id: Ib4ce456e276e0273e57c163dcdd0b33abf863656
Reviewed-on: https://chromium-review.googlesource.com/928403
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Michael Stanton <mvstanton@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51474}
2018-02-22 13:18:48 +00:00
Ross McIlroy
a021b6c42d [Ignition] [TurboFan] Generate speculation poison in code generator.
Moves generation of speculation poison to be based on the PC target vs the
actual PC being executed. The speculation poison is generated in the prologue
of the generated code if CompilationInfo::kGenerateSpeculationPoison is set.
The result is stored in a known register, which can then be read using the
SpeculationPoison machine node.

Currently we need to ensure the SpeculationPoison node is scheduled right after
the code prologue so that the poison register doesn't get clobbered. This is
currently not verified, however it's only use is in RawMachineAssembler where
it is manually scheduled early.

The Ignition bytecode handlers are updated to use this speculation poison
rather than one generated by comparing the target bytecode.

BUG=chromium:798964

Change-Id: I2a3d0cfc694e88d7a8fe893282bd5082f693d5e2
Reviewed-on: https://chromium-review.googlesource.com/893160
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51229}
2018-02-12 09:26:58 +00:00
Ross McIlroy
c9941af275 [Intepreter] Add poisoning to bytecode operand reads.
BUG=chromium:798964

Change-Id: I63c373ef3f27a3295fc79f5c82d78b5fd89a83da
Reviewed-on: https://chromium-review.googlesource.com/888752
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#50925}
2018-01-29 12:56:43 +00:00
Ross McIlroy
cb0bc43f20 [Interpreter] Refactor bytecode register access.
Refactors bytecode register access to avoid having to deal with register indexes
directly.

 - Changes Load/StoreRegister to Load/StoreRegisterAtOperandIndex
 - Adds RegisterList abstraction for dealin with lists of registers
 - Adds helpers for Loading / Storing register pairs / triples.

Change-Id: I34427e4bd7314dce0230572212580d6a93ccc2d4
Reviewed-on: https://chromium-review.googlesource.com/887062
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#50899}
2018-01-26 14:00:58 +00:00
Mathias Bynens
822be9b238 Normalize casing of hexadecimal digits
This patch normalizes the casing of hexadecimal digits in escape
sequences of the form `\xNN` and integer literals of the form
`0xNNNN`.

Previously, the V8 code base used an inconsistent mixture of uppercase
and lowercase.

Google’s C++ style guide uses uppercase in its examples:
https://google.github.io/styleguide/cppguide.html#Non-ASCII_Characters

Moreover, uppercase letters more clearly stand out from the lowercase
`x` (or `u`) characters at the start, as well as lowercase letters
elsewhere in strings.

BUG=v8:7109
TBR=marja@chromium.org,titzer@chromium.org,mtrofin@chromium.org,mstarzinger@chromium.org,rossberg@chromium.org,yangguo@chromium.org,mlippautz@chromium.org
NOPRESUBMIT=true

Cq-Include-Trybots: master.tryserver.blink:linux_trusty_blink_rel;master.tryserver.chromium.linux:linux_chromium_rel_ng
Change-Id: I790e21c25d96ad5d95c8229724eb45d2aa9e22d6
Reviewed-on: https://chromium-review.googlesource.com/804294
Commit-Queue: Mathias Bynens <mathias@chromium.org>
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49810}
2017-12-02 01:24:40 +00:00
Mostyn Bramley-Moore
2551f73eeb [jumbo] fix another set of unittest compilation errors
This makes jumbo_file_merge_limit=50 work again.

Bug: chromium:770684
Change-Id: I5db6566da876d71ea6ba50ff03b7652074b0a35f
Reviewed-on: https://chromium-review.googlesource.com/725818
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Mostyn Bramley-Moore <mostynb@vewd.com>
Cr-Commit-Position: refs/heads/master@{#48728}
2017-10-19 09:15:44 +00:00
Toon Verwaest
1067026ff1 Remove ComputeFlags, simply pass in Code::Kind instead of Code::Flags
TBR: ofrobots@google.com, yangguo@chromium.org
Bug: 
Change-Id: I6cb0704acabf9a7f2334de539a6600db8607baef
Reviewed-on: https://chromium-review.googlesource.com/691720
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48237}
2017-09-29 15:37:27 +00:00
pan.deng@intel.com
d8864701fd [csa] Add constant folding more universally to CodeAssembler operators
Contributed by kanghua.yu@intel.com.

Bug: None
Change-Id: I5651ef38eb0c08deb97770a5eaa985dba2dab9a9
Reviewed-on: https://chromium-review.googlesource.com/604648
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Commit-Queue: Pan Deng <pan.deng@intel.com>
Cr-Commit-Position: refs/heads/master@{#47968}
2017-09-12 10:03:10 +00:00
Jaroslav Sevcik
095de95be1 [interpreter] printing: output the native context index as string
Bug: 
Change-Id: Iedd273d517e2ee2e548a5e9732689114800e6128
Reviewed-on: https://chromium-review.googlesource.com/649749
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Commit-Queue: Jaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#47822}
2017-09-05 12:57:09 +00:00
Michael Starzinger
e461e1c646 [presubmit] Enable and fix "build/namespaces" linter check.
R=clemensh@chromium.org

Change-Id: I42241713b7d14dd1cb321df0570566b0873c10a4
Reviewed-on: https://chromium-review.googlesource.com/647888
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#47793}
2017-09-04 11:24:26 +00:00
Ross McIlroy
51a1514016 [Interpreter] Adapt Call bytecode handlers to drop their stack-frame.
This change adapts the Call bytecode handlers such that they don't require
a stack frame. It does this by modifying the call bytecode handler to
tail-call the Call or InterpreterPushArgsAndCall builtins. As a result, the
callee function will return to the InterpreterEntryTrampoline when it returns
(since this is the return address on the interpreter frame), which is
adapted to dispatch to the next bytecode handler. The return bytecode
handler is modified to tail-call a new InterpreterExitTramoline instead
of returning to the InterpreterEntryTrampoline.

Overall this significanlty reduces the amount of stack space required for
interpreter frames, increasing the maximum depth of recursive calls from
around 6000 to around 12,500 on x64.

BUG=chromium:753705

Change-Id: I23328e4cef878df3aca4db763b47d72a2cce664c
Reviewed-on: https://chromium-review.googlesource.com/634364
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#47617}
2017-08-25 21:32:09 +00:00
Adam Klein
1769f892ce [cleanup] Remove always-off support for tail calls
The tail call implementation is hidden behind the --harmony-tailcalls
flag, which is off-by-default (and has been unstaged since February).
It is known to be broken in a variety of cases, including clusterfuzz
security issues (see sample Chromium issues below). To avoid letting
the implementation bitrot further on trunk, this patch removes it.

Bug: v8:4698, chromium:636914, chromium:724746
Cq-Include-Trybots: master.tryserver.chromium.linux:linux_chromium_rel_ng;master.tryserver.v8:v8_linux_noi18n_rel_ng
Change-Id: I9cb547101456a582374fdf7b1a3f044a9ef33e5c
Reviewed-on: https://chromium-review.googlesource.com/569069
Commit-Queue: Adam Klein <adamk@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46651}
2017-07-13 19:29:05 +00:00
jarin
f0645612c4 This is a first step towards reducing the number of stores/loads when suspending/resuming a generator.
Unfortunately, even for an empty generator, we still use 8 register for various things (try-finally, copies of generator object, parser-introduced temporaries). I will try to get rid of these in separate CLs.

Changes:

- SuspendGenerator bytecode now takes register list to save.
- ResumeGenerator was split into two bytecodes:
  * Resume generator reads the state out and marks the generator as
      'executing'.
  * RestoreGeneratorRegisters reloads the registers from
      the generator.
    + this required adding support for output register list.

- Introduced generator_object_ register in the bytecode generator.
  * in subsequent CLs, I will make better use of it, the goal is
      to get rid if the .generator_object local variable.

- Taught register optimizer to flush unassigned registers.

BUG=v8:6379

Review-Url: https://codereview.chromium.org/2894293003
Cr-Commit-Position: refs/heads/master@{#45675}
2017-06-02 11:55:48 +00:00
Leszek Swirski
57afd0bb07 Reland: [ignition] Add call bytecodes for undefined receiver
Adds a collection of call bytecodes which have an implicit undefined
receiver argument, for cases such as global calls where we know that the
receiver has to be undefined. This way we can skip an LdaUndefined,
decrease bytecode register pressure, and set a more accurate
ConvertReceiverMode on the interpreter and TurboFan call.

As a side effect, the "normal" Call bytecode now becomes a rare case
(only with calls and super property calls), so we get rid of its 0-2
argument special cases and modify CallProperty[N] to use the
NotNullOrUndefined ConvertReceiverMode.

Reland of https://chromium-review.googlesource.com/c/463287 after fixing
tests in https://codereview.chromium.org/2813873002.

Change-Id: I314d69c7643ceec6a5750ffdab60dad38dad09e5
Reviewed-on: https://chromium-review.googlesource.com/474752
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#44582}
2017-04-11 15:52:37 +00:00
Michael Achenbach
925212a1cf Revert "[ignition] Add call bytecodes for undefined receiver"
This reverts commit 751e893591.

Reason for revert: Breaks layout tests:
https://build.chromium.org/p/client.v8.fyi/builders/V8-Blink%20Linux%2064/builds/14885

See:
https://github.com/v8/v8/wiki/Blink-layout-tests

Original change's description:
> [ignition] Add call bytecodes for undefined receiver
> 
> Adds a collection of call bytecodes which have an implicit undefined
> receiver argument, for cases such as global calls where we know that the
> receiver has to be undefined. This way we can skip an LdaUndefined,
> decrease bytecode register pressure, and set a more accurate
> ConvertReceiverMode on the interpreter and TurboFan call.
> 
> As a side effect, the "normal" Call bytecode now becomes a rare case
> (only with calls and super property calls), so we get rid of its 0-2
> argument special cases and modify CallProperty[N] to use the
> NotNullOrUndefined ConvertReceiverMode.
> 
> Change-Id: I9374a32fefd66fc0251b5193bae7a6b7dc31eefc
> Reviewed-on: https://chromium-review.googlesource.com/463287
> Commit-Queue: Leszek Swirski <leszeks@chromium.org>
> Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#44530}

TBR=rmcilroy@chromium.org,mstarzinger@chromium.org,leszeks@chromium.org,v8-reviews@googlegroups.com,v8-mips-ports@googlegroups.com,v8-ppc-ports@googlegroups.com,v8-x87-ports@googlegroups.com,bmeurer@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Change-Id: I7629dec609d0ec938ce7105d6c1c74884e5f9272
Reviewed-on: https://chromium-review.googlesource.com/474744
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#44548}
2017-04-11 06:47:01 +00:00
Leszek Swirski
751e893591 [ignition] Add call bytecodes for undefined receiver
Adds a collection of call bytecodes which have an implicit undefined
receiver argument, for cases such as global calls where we know that the
receiver has to be undefined. This way we can skip an LdaUndefined,
decrease bytecode register pressure, and set a more accurate
ConvertReceiverMode on the interpreter and TurboFan call.

As a side effect, the "normal" Call bytecode now becomes a rare case
(only with calls and super property calls), so we get rid of its 0-2
argument special cases and modify CallProperty[N] to use the
NotNullOrUndefined ConvertReceiverMode.

Change-Id: I9374a32fefd66fc0251b5193bae7a6b7dc31eefc
Reviewed-on: https://chromium-review.googlesource.com/463287
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#44530}
2017-04-10 15:30:11 +00:00
Marja Hölttä
83849da70f [iwyu] Pre-work for removing unallowed include macro-assembler.h -> assembler-inl.h
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}
2017-02-23 12:10:21 +00:00
Daniel Clifford
bd21c2bd04 [ignition] Optimize reloading of registers before Dispatch
Before this patch, the registers needed for bytecode dispatch in interpreter
handlers were inconsistently stored in the interpreter frame and/or kept in
values that remained live across calls.

After this patch, these registers are explicitly reloaded after calls, making it
possible to elide the spills of those registers before the call in many cases.

Some highlights from the CL:

* Added methods to the CSA and InterpreterAssembler to efficiently store and
  load Smis values and Smi interpreter registers on x64 without explicit
  tagging/untagging.

* Created Variables for all of the interpreter-internal values that need to be
  reloaded before bytecode dispatch at the end of an interpreter handler.

* The bytecode offset can be written out early in a handler by marking it
  has having a call along it's critical path. By moving this early in a
  handler, it becomes possible to use memory operands for pushes used to
  marshall parameters when making calls.

Change-Id: Icf8d7798789f88a4489e06a7092616bbbb881577
Reviewed-on: https://chromium-review.googlesource.com/442566
Commit-Queue: Daniel Clifford <danno@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#43260}
2017-02-16 19:30:39 +00:00
ishell@chromium.org
32971301ea Rename TypeFeedbackVector to FeedbackVector.
... and TypeFeedbackMetadata to FeedbackMetadata.

BUG=

Change-Id: I2556d1c2a8f37b8cf3d532cc98d973b6dc7e9e6c
Reviewed-on: https://chromium-review.googlesource.com/439244
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Michael Stanton <mvstanton@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Reviewed-by: Hannes Payer <hpayer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#42999}
2017-02-07 14:46:36 +00:00
mvstanton
aea3ce3df3 [TypeFeedbackVector] Root feedback vectors at function literal site.
TypeFeedbackVectors are strongly rooted by a closure. However, in modern
JavaScript closures are created and abandoned more freely. An important
closure may not be present in the root-set at time of garbage collection,
even though we've cached optimized code and use it regularly. For
example, consider leaf functions in an event dispatching system. They may
well be "hot," but tragically non-present when we collect the heap.

Until now, we've relied on a weak root to cache the feedback vector in
this case. Since there is no way to signal intent or relative importance,
this weak root is as susceptible to clearing as any other weak root at
garbage collection time.

Meanwhile, the feedback vector has become more important. All of our
ICs store their data there. Literal and regex boilerplates are stored there.
If we lose the vector, then we not only lose optimized code built from
it, we also lose the very feedback which allowed us to create that optimized
code. Therefore it's vital to express that dependency through the root
set.

This CL does this by creating a strong link to a feedback
vector at the instantiation site of the function closure.
This instantiation site is in the code and feedback vector
of the outer closure.

BUG=v8:5456

Review-Url: https://codereview.chromium.org/2674593003
Cr-Commit-Position: refs/heads/master@{#42953}
2017-02-06 10:18:05 +00:00
mvstanton
93f05b64ae [TypeFeedbackVector] Combine the literals array and the feedback vector.
They have the same lifetime. It's a match!

Both structures are native context dependent and dealt with (creation,
clearing, gathering feedback) at the same time. By treating the spaces used
for literal boilerplates as feedback vector slots, we no longer have to keep
track of the materialized literal count elsewhere.

A follow-on CL removes even more parser infrastructure related to this count.

BUG=v8:5456

Review-Url: https://codereview.chromium.org/2655853010
Cr-Commit-Position: refs/heads/master@{#42771}
2017-01-30 12:31:35 +00:00