Reason for revert:
False alarm, bot hiccup
Original issue's description:
> Revert of Thread maybe-assigned through the bytecodes. (patchset #5 id:80001 of https://codereview.chromium.org/2655733003/ )
>
> Reason for revert:
> needed for properly reverting f3ae5ccf57
>
> Original issue's description:
> > Thread maybe-assigned through the bytecodes.
> >
> > This introduces LoadImmutableContextSlot and LoadImmutableCurrentContextSlot
> > bytecodes, which are emitted when reading from never-assigned context slot.
> >
> > There is a subtlety here: the slot are not immutable, the meaning is
> > actually undefined-or-hole-or-immutable.
> >
> > Review-Url: https://codereview.chromium.org/2655733003
> > Cr-Commit-Position: refs/heads/master@{#43000}
> > Committed: 17c2dd3886
>
> TBR=rmcilroy@chromium.org,bmeurer@chromium.org,neis@chromium.org,jarin@chromium.org
> # Skipping CQ checks because original CL landed less than 1 days ago.
> NOPRESUBMIT=true
> NOTREECHECKS=true
> NOTRY=true
>
> Review-Url: https://codereview.chromium.org/2680923003
> Cr-Commit-Position: refs/heads/master@{#43011}
> Committed: ece4e54a31TBR=rmcilroy@chromium.org,bmeurer@chromium.org,neis@chromium.org,jarin@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
Review-Url: https://codereview.chromium.org/2679953003
Cr-Commit-Position: refs/heads/master@{#43012}
Reason for revert:
needed for properly reverting f3ae5ccf57
Original issue's description:
> Thread maybe-assigned through the bytecodes.
>
> This introduces LoadImmutableContextSlot and LoadImmutableCurrentContextSlot
> bytecodes, which are emitted when reading from never-assigned context slot.
>
> There is a subtlety here: the slot are not immutable, the meaning is
> actually undefined-or-hole-or-immutable.
>
> Review-Url: https://codereview.chromium.org/2655733003
> Cr-Commit-Position: refs/heads/master@{#43000}
> Committed: 17c2dd3886TBR=rmcilroy@chromium.org,bmeurer@chromium.org,neis@chromium.org,jarin@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
Review-Url: https://codereview.chromium.org/2680923003
Cr-Commit-Position: refs/heads/master@{#43011}
This introduces LoadImmutableContextSlot and LoadImmutableCurrentContextSlot
bytecodes, which are emitted when reading from never-assigned context slot.
There is a subtlety here: the slot are not immutable, the meaning is
actually undefined-or-hole-or-immutable.
Review-Url: https://codereview.chromium.org/2655733003
Cr-Commit-Position: refs/heads/master@{#43000}
... 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}
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}
Rename to Construct and ConstructWithSpread, to match the names of
the JSOperators used.
Unfortunately, I can't find a way for auto-formatting to stay happy unless we
change the indentation for the whole BYTECODE_LIST macro.
Review-Url: https://codereview.chromium.org/2663963003
Cr-Commit-Position: refs/heads/master@{#42840}
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}
Since JumpLoop is always backwards, and other jumps are always forwards,
we can store the jump offset as an always positive integer and decide on
the jump direction based on the bytecode. This will save a small amount
of space for large-ish for loops (>128 bytecodes).
Review-Url: https://codereview.chromium.org/2641443002
Cr-Commit-Position: refs/heads/master@{#42638}
We can share almost all of the architecture-specific builtin code with super-call-with-spread.
Info to port-writers: The code in CheckSpreadAndPushToStack has changed slightly from what was in Generate_ConstructWithSpread, in that we take the length of the spreaded parameters from the JSArray rather than the FixedArray backing store.
BUG=v8:5511
Review-Url: https://codereview.chromium.org/2649143002
Cr-Commit-Position: refs/heads/master@{#42632}
Reason for revert:
Causes a few bugs caught by clusterfuzz.
Original issue's description:
> [Ignition/turbo] Add a CallWithSpread bytecode.
>
> Also, emit a NewWithSpread bytecode for CallNew AST nodes where possible, rather than desugaring in the parser.
>
> BUG=v8:5511
>
> Review-Url: https://codereview.chromium.org/2629363002
> Cr-Commit-Position: refs/heads/master@{#42455}
> Committed: 4bae43471dTBR=bmeurer@chromium.org,rmcilroy@chromium.org,verwaest@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:5511
Review-Url: https://codereview.chromium.org/2642843002
Cr-Commit-Position: refs/heads/master@{#42470}
Also, emit a NewWithSpread bytecode for CallNew AST nodes where possible, rather than desugaring in the parser.
BUG=v8:5511
Review-Url: https://codereview.chromium.org/2629363002
Cr-Commit-Position: refs/heads/master@{#42455}
Moves constant element/property array building to be deferred for
igition and on-demand for the other compilers, and splits off the
object/array literal depth/flag initialisation from the array building.
BUG=v8:5832
Review-Url: https://codereview.chromium.org/2625873009
Cr-Commit-Position: refs/heads/master@{#42362}
This changes the NewClosure interface descriptor, but ignores
the additional vector/slot arguments for now. The feedback vector
gets larger, as it holds a space for each literal array. A follow-on
CL will constructively use this space.
BUG=v8:5456
Review-Url: https://codereview.chromium.org/2614373002
Cr-Commit-Position: refs/heads/master@{#42146}
Downside: this adds all kinds of weird includes in the .cc files.
(See design doc linked in the bug.)
BUG=v8:5402
Review-Url: https://codereview.chromium.org/2622503002
Cr-Commit-Position: refs/heads/master@{#42140}
Add a feedback vector slot for computed property names in object
and class literals. Introduce new slot kind for storing
computed property names.
Change StaDataPropertyInLiteral to use the accumulator (again), so
we don't exceed Bytecodes::kMaxOperands.
We assume that most computed property names are
symbols. Therefore we should see performance
improvements, even if we deal with monomorphic ICs only.
This CL only collects feedback but does not use
it in Reduce() yet.
BUG=v8:5624
Review-Url: https://codereview.chromium.org/2587393006
Cr-Commit-Position: refs/heads/master@{#42082}
... and add explicit CallPrologue/CallEpilogue callbacks to CodeAssemblerState instead.
This will allow IntepreterAssembler to use any other helper assembler.
TBR=rmcilroy@chromium.org
BUG=
Review-Url: https://codereview.chromium.org/2600183004
Cr-Commit-Position: refs/heads/master@{#41973}
Reason for revert:
Speculative revert because of blocked roll: https://codereview.chromium.org/2596013002/
Original issue's description:
> [TypeFeedbackVector] Root literal arrays in function literals slots
>
> Literal arrays and feedback vectors for a function can be garbage
> collected if we don't have a rooted closure for the function, which
> happens often. It's expensive to come back from this (recreating
> boilerplates and gathering feedback again), and the cost is
> disproportionate if the function was inlined into optimized code.
>
> To guard against losing these arrays when we need them, we'll now
> create literal arrays when creating the feedback vector for the outer
> closure, and root them strongly in that vector.
>
> BUG=v8:5456
>
> Review-Url: https://codereview.chromium.org/2504153002
> Cr-Commit-Position: refs/heads/master@{#41893}
> Committed: 93df094081TBR=bmeurer@chromium.org,mlippautz@chromium.org,mvstanton@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:5456
Review-Url: https://codereview.chromium.org/2597163002
Cr-Commit-Position: refs/heads/master@{#41917}
Literal arrays and feedback vectors for a function can be garbage
collected if we don't have a rooted closure for the function, which
happens often. It's expensive to come back from this (recreating
boilerplates and gathering feedback again), and the cost is
disproportionate if the function was inlined into optimized code.
To guard against losing these arrays when we need them, we'll now
create literal arrays when creating the feedback vector for the outer
closure, and root them strongly in that vector.
BUG=v8:5456
Review-Url: https://codereview.chromium.org/2504153002
Cr-Commit-Position: refs/heads/master@{#41893}
eval() may introduce a scope which needs to be represented as a context at
runtime, e.g.,
eval('var x; let y; ()=>y')
introduces a variable y which needs to have a context allocated for it. However,
when traversing upwards to find the declaration context for a variable which leaks,
as the declaration of x does above, this context has to be understood to not be
a declaration context in sloppy mode.
This patch makes that distinction by introducing a different map for eval-introduced
contexts. A dynamic search for the appropriate context will continue past an eval
context to find the appropriate context. Marking contexts as eval contexts rather
than function contexts required updates in each compiler backend.
BUG=v8:5295, chromium:648719
Review-Url: https://codereview.chromium.org/2435023002
Cr-Commit-Position: refs/heads/master@{#41869}
Encode the PropertyAttribute and whether the function
names must be set as a flag instead of setting two registers.
BUG=v8:5624
Review-Url: https://codereview.chromium.org/2586463002
Cr-Commit-Position: refs/heads/master@{#41812}
This is so that a NotSuperConstructor error is thrown before evaluating the
arguments to the super constructor. Besides updating the runtime function, a
new bytecode GetSuperConstructor is introduced.
BUG=v8:5336
Review-Url: https://codereview.chromium.org/2504553003
Cr-Commit-Position: refs/heads/master@{#41788}
Transform LdaNull/LdaUndefined followed by StrictEquality to TestNull/TestUndefined.
This would avoid a call to the compare IC. In the bytecode-graph builder these are
mapped to StrictEqual javascript operator. When reducing this operator, we already
optimize the cases for null/undefined.
BUG=v8:4280
Review-Url: https://codereview.chromium.org/2554723004
Cr-Commit-Position: refs/heads/master@{#41768}
This introduces an explicit struct for the communication channel between
the {ArrayLiteral} AST node and the corresponding runtime methods. Those
methods take a pair of {ElementsKind} as well as an array (can either be
a FixedArray or a FixedDoubleArray) of constant values.
For bonus points it also reduces the size of the involved heap object by
one word (i.e. length field of FixedArray not needed anymore).
R=mvstanton@chromium.org
Review-Url: https://codereview.chromium.org/2581683003
Cr-Commit-Position: refs/heads/master@{#41752}
Allocate the registers used as arguments to a call on-demand after visiting the
argument (or reciever). This means that the visited expression can use registers
that would otherwise have been allocated for arguments which haven't been
visited yet.
The reason for doing this is to avoid keeping things live in registers
unecessarily for chained function calls, which avoids a memory leak for
functions which chain a large number of calls with large temporary arguments /
recievers.
BUG=chromium:672027
Review-Url: https://codereview.chromium.org/2557173004
Cr-Commit-Position: refs/heads/master@{#41714}
Templatizes the AccumulatorUsage and OperandType for BytecodeNode creation and
BytecodeRegisterOptimizer::PrepareForBytecode. This allows the compiler to
statically know whether the bytecode being created accesses the accumulator
and what operand types need scaling, avoiding runtime checks in the code.
Also removes BytecodeNode::set_bytecode methods.
Review-Url: https://codereview.chromium.org/2542903003
Cr-Commit-Position: refs/heads/master@{#41706}
Introduces:
- a new AST node representing the GetIterator() algorithm in the specification, to be used by ForOfStatement, YieldExpression (in the case of delegating yield*), and the future `for-await-of` loop proposed in http://tc39.github.io/proposal-async-iteration/#sec-async-iterator-value-unwrap-functions.
- a new opcode (JumpIfJSReceiver), which is useful for `if Type(object) is not Object` checks which are common throughout the specification. This node is easily eliminated by TurboFan.
The AST node is desugared specially in bytecode, rather than manually when building the AST. The benefit of this is that desugaring in the BytecodeGenerator is much simpler and easier to understand than desugaring the AST.
This also reduces parse time very slightly, and allows us to use LoadIC rather than KeyedLoadIC, which seems to have better baseline performance. This results in a ~20% improvement in test/js-perf-test/Iterators micro-benchmarks, which I believe owes to the use of the slightly faster LoadIC as opposed to the KeyedLoadIC in the baseline case. Both produce identical optimized code via TurboFan when the type check can be eliminated, and the load can be replaced with a constant value.
BUG=v8:4280
R=bmeurer@chromium.org, rmcilroy@chromium.org, adamk@chromium.org, neis@chromium.org, jarin@chromium.orgTBR=rossberg@chromium.org
Review-Url: https://codereview.chromium.org/2557593004
Cr-Commit-Position: refs/heads/master@{#41555}
This just calls into a runtime function for implementation currently.
Intermediate step in speeding up constructor calls containing a spread.
The NewWithSpread bytecode will probably end up having different arguments with future CLs - the constructor and the new.target should have their own regs. For now we are calling into the runtime function, so we need the regs together.
BUG=v8:5659
Review-Url: https://codereview.chromium.org/2541113004
Cr-Commit-Position: refs/heads/master@{#41542}
Equality with null/undefined is equivalent to a check on the undetectable bit
on the map of the object. This would be more efficient than performing the entire
comparison operation.
This cl introduces:
1. A new bytecode called TestUndetectable that checks if the object is null/undefined.
2. Updates peeophole optimizer to emit TestUndetectable when a LdaNull/Undefined
precedes equality check.
4. TestUndetectable is transformed to ObjectIsUndetectable operator when building
turbofan graph.
BUG=v8:4280
Review-Url: https://codereview.chromium.org/2547043002
Cr-Commit-Position: refs/heads/master@{#41514}
Reorders the jump bytecodes so that the majority of jump checks can be
implemented as range checks (rather than a list of comparisons that get
compiled to a bunch of jumps).
Review-Url: https://codereview.chromium.org/2537123002
Cr-Commit-Position: refs/heads/master@{#41498}
This allows us to optimise the bytecode liveness analysis to jump
directly to previously seen indices. The analysis is optimised to store
a stack of loop ends (JumpLoop bytecode indices), and iterate through
these indices directly rather than looping through the bytecode array to
find them.
Review-Url: https://codereview.chromium.org/2536653003
Cr-Commit-Position: refs/heads/master@{#41485}
This pre-calculates and stores a vector of bytecode offsets, and then allows
one to iterate over it backwards. This could probably be adapted to a
bidirectional/random access iterator if we wanted to, but for now reverse
is all we need.
Review-Url: https://codereview.chromium.org/2518003002
Cr-Commit-Position: refs/heads/master@{#41153}
Add bytecode for defining data properties, which initially just calls the runtime function.
BUG=v8:5624
Review-Url: https://codereview.chromium.org/2510743002
Cr-Commit-Position: refs/heads/master@{#41101}
The reasons are:
1) The names dictionaries in the feedback metadata seems to consume a lot of memory
and the idea didn't payoff.
2) The absence of a name parameter blocks data handlers support in LoadGlobalIC.
This CL reverts a part of r37278 (https://codereview.chromium.org/2096653003/).
BUG=chromium:576312, v8:5561
Review-Url: https://codereview.chromium.org/2510653002
Cr-Commit-Position: refs/heads/master@{#41046}
This is in preparation for introducing more specialized
CodeStubAssembler subclasses. The state object can be handed
around, while the Assembler instances are temporary-scoped.
BUG=v8:5628
Original review: https://codereview.chromium.org/2498073002/
Review-Url: https://codereview.chromium.org/2502293002
Cr-Commit-Position: refs/heads/master@{#41028}
Adds a bytecode to set and retrieve the pending message. This avoids a
runtime call in finally blocks, and also ensures that TurboFan builds a
graph using the SetMessage / LoadMessage nodes instead of inserting a
runtime call.
BUG=chromium:662334
Review-Url: https://codereview.chromium.org/2501503005
Cr-Commit-Position: refs/heads/master@{#41023}
Reason for revert:
https://build.chromium.org/p/client.v8/builders/V8%20Linux%20-%20shared doesn't want to compile. Missing export annotation?
Original issue's description:
> [refactoring] Split CodeAssemblerState out of CodeAssembler
>
> This is in preparation for introducing more specialized
> CodeStubAssembler subclasses. The state object can be handed
> around, while the Assembler instances are temporary-scoped.
>
> BUG=v8:5628
TBR=ishell@chromium.org,mstarzinger@chromium.org,jkummerow@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:5628
Review-Url: https://codereview.chromium.org/2504913002
Cr-Commit-Position: refs/heads/master@{#41018}
This is in preparation for introducing more specialized
CodeStubAssembler subclasses. The state object can be handed
around, while the Assembler instances are temporary-scoped.
BUG=v8:5628
Review-Url: https://codereview.chromium.org/2498073002
Cr-Commit-Position: refs/heads/master@{#41015}
SourcePosition::InliningId() refers to a the new table DeoptimizationInputData::InliningPositions(), which provides the following data for every inlining id:
- The inlined SharedFunctionInfo as an offset into DeoptimizationInfo::LiteralArray
- The SourcePosition of the inlining. Recursively, this yields the full inlining stack.
Before the Code object is created, the same information can be found in CompilationInfo::inlined_functions().
If SourcePosition::InliningId() is SourcePosition::kNotInlined, it refers to the outer (non-inlined) function.
So every SourcePosition has full information about its inlining stack, as long as the corresponding Code object is known. The internal represenation of a source position is a positive 64bit integer.
All compilers create now appropriate source positions for inlined functions. In the case of Turbofan, this required using AstGraphBuilderWithPositions for inlined functions too. So this class is now moved to a header file.
At the moment, the additional information in source positions is only used in --trace-deopt and --code-comments. The profiler needs to be updated, at the moment it gets the correct script offsets from the deopt info, but the wrong script id from the reconstructed deopt stack, which can lead to wrong outputs. This should be resolved by making the profiler use the new inlining information for deopts.
I activated the inlined deoptimization tests in test-cpu-profiler.cc for Turbofan, changing them to a case where the deopt stack and the inlining position agree. It is currently still broken for other cases.
The following additional changes were necessary:
- The source position table (internal::SourcePositionTableBuilder etc.) supports now 64bit source positions. Encoding source positions in a single 64bit int together with the difference encoding in the source position table results in very little overhead for the inlining id, since only 12% of the source positions in Octane have a changed inlining id.
- The class HPositionInfo was effectively dead code and is now removed.
- SourcePosition has new printing and information facilities, including computing a full inlining stack.
- I had to rename compiler/source-position.{h,cc} to compiler/compiler-source-position-table.{h,cc} to avoid clashes with the new src/source-position.cc file.
- I wrote the new wrapper PodArray for ByteArray. It is a template working with any POD-type. This is used in DeoptimizationInputData::InliningPositions().
- I removed HInlinedFunctionInfo and HGraph::inlined_function_infos, because they were only used for the now obsolete Crankshaft inlining ids.
- Crankshaft managed a list of inlined functions in Lithium: LChunk::inlined_functions. This is an analog structure to CompilationInfo::inlined_functions. So I removed LChunk::inlined_functions and made Crankshaft use CompilationInfo::inlined_functions instead, because this was necessary to register the offsets into the literal array in a uniform way. This is a safe change because LChunk::inlined_functions has no other uses and the functions in CompilationInfo::inlined_functions have a strictly longer lifespan, being created earlier (in Hydrogen already).
BUG=v8:5432
Review-Url: https://codereview.chromium.org/2451853002
Cr-Commit-Position: refs/heads/master@{#40975}
We seem to get some small wins from avoiding the Ldr bytecodes, probably due
to reduced icache pressure since there are less bytecode handlers. Replace
the Ldr bytecodes with Star lookahead inlined into the Lda versions.
Also fixes IsAccumulatorLoadWithoutEffects to include LdaContextSlot and
LdaCurrentContextSlot
BUG=v8:4280
Review-Url: https://codereview.chromium.org/2489513005
Cr-Commit-Position: refs/heads/master@{#40883}
The Ldr[Named/Keyed]Property bytecodes are problematic for the deoptimizer when
inlining accessors in TurboFan. Remove them and replace with a Star lookahead
in the bytecode handlers for Lda[Named/Keyed]Property.
BUG=v8:4280
Review-Url: https://codereview.chromium.org/2485383002
Cr-Commit-Position: refs/heads/master@{#40860}
This introduces two new bytecodes LdaModuleVariable and StaModuleVariable,
replacing the corresponding runtime calls.
Support in the bytecode graph builder exists only in the form of runtime calls.
BUG=v8:1569
Review-Url: https://codereview.chromium.org/2471033004
Cr-Commit-Position: refs/heads/master@{#40825}
The existing Load/StoreContextElement operations take the index as an int. This
CL adds versions that take the index as a Node. These already existed in the
interpreter-assembler, from which they are now removed.
R=mstarzinger@chromium.org, rmcilroy@chromium.org
BUG=
Review-Url: https://codereview.chromium.org/2473003004
Cr-Commit-Position: refs/heads/master@{#40810}
