This is only an estimate since it counts objects that could be shared,
for example strings, cow arrays, heap numbers, etc.
It however ignores objects that could be shared, but may only be used
by the context to be measured, for example shared function infos,
script objects, scope infos, etc.
R=jochen@chromium.org
Review URL: https://codereview.chromium.org/1268333004
Cr-Commit-Position: refs/heads/master@{#30029}
To avoid tanking context startup performance, only the actual installation of the
JS-exposed API is flag-guarded. The remainder of the implementation still
resides in the snapshot.
Review URL: https://codereview.chromium.org/1257063003
Cr-Commit-Position: refs/heads/master@{#30017}
Added a separate flag for this, since we intend to enable it for the linear allocator as well. Currently, the option is "on" for greedy, as a point in time to enable its testing (through the greedy allocator bots).
BUG=
Review URL: https://codereview.chromium.org/1256313003
Cr-Commit-Position: refs/heads/master@{#30005}
The BytecodeArrayBuilder has responsibility for emitting the BytecodeArray. It will be used by the AST walker.
Bytecode now uses an accumulator plus registers rather being pure register based.
Update BytecodeArray::Disassemble to print operand information.
BUG=v8:4280
LOG=N
Review URL: https://codereview.chromium.org/1266713004
Cr-Commit-Position: refs/heads/master@{#29970}
This is the first step in cutting the Gordian linkage/linkage-impl knot.
This basically changes the axis along which we organize call descriptor
building logic from having platform-specific files dedicated to all call
descriptor types to having call-descriptor-type-specific files that have
The next step is to factor the JS, code stub, and runtime call descriptors
similarly, dumping them into:
compiler/js-linkage.cc
compiler/runtime-linkage.cc
compiler/code-stub-linkage.cc
or, alternatively, all of them just into compiler/js-linkage.cc.
This also anticipates a wasm-linkage.cc file in the future.
R=bmeurer@chromium.org,danno@chromium.org
BUG=
Review URL: https://codereview.chromium.org/1266603002
Cr-Commit-Position: refs/heads/master@{#29931}
Adds basic support for generation of interpreter bytecode handler code
snippets. The InterpreterAssembler class exposes a set of low level,
interpreter specific operations which can be used to build a Turbofan
graph. The Interpreter class generates a bytecode handler snippet for
each bytecode by assembling operations using an InterpreterAssembler.
Currently only two simple bytecodes are supported: LoadLiteral0 and Return.
BUG=v8:4280
LOG=N
Review URL: https://codereview.chromium.org/1239793002
Cr-Commit-Position: refs/heads/master@{#29814}
Using the GraphBuilder base class forces each node creation to go
through a virtual function dispatch just for the sake of saving the
duplication of the NewNode helper methods. In total that added up to
saving minus (sic!) six lines of code.
R=titzer@chromium.org
Review URL: https://codereview.chromium.org/1252093002
Cr-Commit-Position: refs/heads/master@{#29799}
In many cases, the context that TurboFan's ASTGraphBuilder or subsequent
reduction operations attaches to nodes does not need to be that exact
context, but rather only needs to be one with the same native context,
because it is used internally only to fetch the native context, e.g. for
creating and throwing exceptions.
This reducer recognizes common cases where the context that is specified
for a node can be relaxed to a canonical, less specific one. This
relaxed context can either be the enclosing function's context or a specific
Module or Script context that is explicitly created within the function.
This optimization is especially important for TurboFan-generated code stubs
which use context specialization and inlining to generate optimal code.
Without context relaxation, many extraneous moves are generated to pass
exactly the right context to internal functions like ToNumber and
AllocateHeapNumber, which only need the native context. By turning context
relaxation on, these moves disappear because all these common internal
context uses are unified to the context passed into the stub function, which
is typically already in the correct context register and remains there for
short stubs. It also eliminates the explicit use of a specialized context
constant in the code stub in these cases, which could cause memory leaks.
Review URL: https://codereview.chromium.org/1244583003
Cr-Commit-Position: refs/heads/master@{#29763}
This CL exposes the constructor function, defines type related
information, and implements value type semantics.
It also refactors test/mjsunit/samevalue.js to test SameValue and SameValueZero.
TEST=test/mjsunit/harmony/simd.js, test/cctest/test-simd.cc
LOG=Y
BUG=v8:4124
Committed: https://crrev.com/e5ed3bee99807c502fa7d7a367ec401e16d3f773
Cr-Commit-Position: refs/heads/master@{#29689}
Review URL: https://codereview.chromium.org/1219943002
Cr-Commit-Position: refs/heads/master@{#29712}
This CL exposes the constructor function, defines type related
information, and implements value type semantics.
It also refactors test/mjsunit/samevalue.js to test SameValue and SameValueZero.
TEST=test/mjsunit/harmony/simd.js, test/cctest/test-simd.cc
LOG=Y
BUG=v8:4124
Review URL: https://codereview.chromium.org/1219943002
Cr-Commit-Position: refs/heads/master@{#29689}
Until now, TF-generated code stubs piggy-backed off of the builtin
context. Since generation of code stubs is lazy, stubs generated at
different times in different native contexts would contain embedded
pointers different builtin contexts, leading to cross-context references
and memory leaks.
After this CL, all TF-generated code stubs are generated inside a
internal thinned-out, native context that lives solely for the
purpose of hosting generated code stubs.
Review URL: https://codereview.chromium.org/1213203007
Cr-Commit-Position: refs/heads/master@{#29593}
The breakage to Chrome seems to be based on @@isConcatSpreadable
and turning that part off with this patch fixes the Maps Tips & Tricks
test case.
BUG=chromium:507553
LOG=Y
R=adamk
Review URL: https://codereview.chromium.org/1226063002
Cr-Commit-Position: refs/heads/master@{#29545}
Optimize string "length" property access based on static type
information if possible, but also optimistically optimize the access
based on type feedback from the LoadIC.
R=jarin@chromium.org
Review URL: https://codereview.chromium.org/1216593003
Cr-Commit-Position: refs/heads/master@{#29543}
The RawMachineAssembler will be used to build the interpreter, so it needs
to move back to src/compiler.
This reverts commit b5b00cc031.
BUG=v8:4280
LOG=N
Review URL: https://codereview.chromium.org/1221303014
Cr-Commit-Position: refs/heads/master@{#29519}
We have to reland these two commits at once, because the first breaks
some asm.js benchmarks without the second. The change was reverted
because of bogus checks in the verifier, which will not work in the
presence of OSR (and where hidden because of the type back propagation
hack in OSR so far). Original messages are below:
[turbofan] Add new JSFrameSpecialization reducer.
The JSFrameSpecialization specializes an OSR graph to the current
unoptimized frame on which we will perform the on-stack replacement.
This is used for asm.js functions, where we cannot reuse the OSR
code object anyway because of context specialization, and so we could as
well specialize to the max instead.
It works by replacing all OsrValues in the graph with their values
in the JavaScriptFrame.
The idea is that using this trick we get better performance without
doing the unsound backpropagation of types to OsrValues later. This
is the first step towards fixing OSR for TurboFan.
[turbofan] Perform OSR deconstruction early and remove type propagation.
This way we don't have to deal with dead pre-OSR code in the graph
and risk optimizing the wrong code, especially we don't make
optimistic assumptions in the dead code that leaks into the OSR code
(i.e. deopt guards are in dead code, but the types propagate to OSR
code via the OsrValue type back propagation).
BUG=v8:4273
LOG=n
R=jarin@chromium.org
Review URL: https://codereview.chromium.org/1226673005
Cr-Commit-Position: refs/heads/master@{#29486}
The JSFrameSpecialization specializes an OSR graph to the current
unoptimized frame on which we will perform the on-stack replacement.
This is used for asm.js functions, where we cannot reuse the OSR code
object anyway because of context specialization, and so we could as well
specialize to the max instead.
It works by replacing all OsrValues in the graph with their values in
the JavaScriptFrame.
The idea is that using this trick we get better performance without
doing the unsound backpropagation of types to OsrValues later. This is
the first step towards fixing OSR for TurboFan.
R=jarin@chromium.org
BUG=v8:4273
LOG=n
Review URL: https://codereview.chromium.org/1225683004
Cr-Commit-Position: refs/heads/master@{#29476}
Conditionally including Array and TypedArray methods seems to cause
a slowdown in V8 context creation, possibly due to the new code added.
BUG=chromium:504629
R=adamk@chromium.org
LOG=Y
Review URL: https://codereview.chromium.org/1215863003
Cr-Commit-Position: refs/heads/master@{#29430}
Separated core greedy allocator concepts, exposing the APIs we would want to continue working with. In particular, this change completely reworks CoalescedLiveRanges to reflect the fact that we expect more than one possible conflict, scrapping the initial design of the structure. Since this is a critical part of the design, this change may be thought of as a full rewrite of the algorithm.
Reduced all heuristics to just 2 essential ones: split "somewhere", which we'll still need when all other heuristics fail; and spill.
Introduced a simple primitive for splitting - at GapPosition::START. The goal is to use such primitives to quickly and reliably author heuristics.
I expected this primitive to "just work" for any arbitrary instruction index within a live range - e.g. its middle. That's not the case, it seems to upset execution in certain scenarios. Restricting to either before/after use positions seems to work. I'm still investigating what the source of failures is in the case of "arbitrary instruction in the range" case.
I intended to document the rationale and prove the soundness of always using START for splits, but I will postpone to after this last remaining issue is resolved.
Review URL: https://codereview.chromium.org/1205173002
Cr-Commit-Position: refs/heads/master@{#29352}
The three different concerns that the ControlReducer used to deal with
are now properly separated into
a.) DeadCodeElimination, which is a regular AdvancedReducer, that
propagates Dead via control edges,
b.) CommonOperatorReducer, which does strength reduction on common
operators (i.e. Branch, Phi, and friends), and
c.) GraphTrimming, which removes dead->live edges from the graph.
This will make it possible to run the DeadCodeElimination together with
other passes that actually introduce Dead nodes, i.e. typed lowering;
and it opens the door for general inlining without two stage fix point
iteration.
To make the DeadCodeElimination easier and more uniform, we basically
reverted the introduction of DeadValue and DeadEffect, and changed the
Dead operator to produce control, value and effect. Note however that
this is not a requirement, but merely a way to make dead propagation
easier and more uniform. We could always go back and decide to have
different Dead operators if some other change requires that.
Note that there are several additional opportunities for cleanup now,
i.e. OSR deconstruction could be a regular reducer now, and we don't
need to use TheHole as dead value marker in the GraphReducer. And we can
actually run the dead code elimination together with the other passes
instead of using separate passes over the graph. We will do this in
follow up CLs.
R=jarin@chromium.org, mstarzinger@chromium.org
Review URL: https://codereview.chromium.org/1193833002
Cr-Commit-Position: refs/heads/master@{#29146}
Up until now that was still mixed with control reduction in the
ControlReducer. This separation allows us to remove the horrible
Reducer::Finish hack and also do graph trimming at more appropriate
places in the pipeline (i.e. trim dead nodes after generic lowering,
which can also make nodes dead).
R=jarin@chromium.org,mstarzinger@chromium.org
Review URL: https://codereview.chromium.org/1188433010
Cr-Commit-Position: refs/heads/master@{#29077}
Opportunistically removed GreedyAllocator::TryReuseSpillForPhi because it is actually unsuitable for Greedy. It was copied from Linear and it relies on hints, however, the current implementation of hints assumes linear scan.
This change doesn't aim to address performance nor correctness for Greedy.
BUG=
Review URL: https://codereview.chromium.org/1184183002
Cr-Commit-Position: refs/heads/master@{#29054}
This patch includes the following changes.
1, Enable the turbofan backend support for X87 platform. It depends on previous CL: 3fdfebd26.
2, Enable the test cases which are disabled because turbofan for X87 was not enabled.
BUG=v8:4135
LOG=N
Review URL: https://codereview.chromium.org/1179763004
Cr-Commit-Position: refs/heads/master@{#29049}
Pushed the detection logic down to ParseAndClassifyIdentifier in
preparation to having patterns in parameter positions.
R=arv@chromium.org,rossberg@chromium.org,wingo@igalia.com
BUG=v8:811
LOG=N
Review URL: https://codereview.chromium.org/1170153003
Cr-Commit-Position: refs/heads/master@{#28876}
In a nutshell: The FILTER_KEY builtin is gone, and was replaced by a
simple runtime call to ForInFilter, which does everything and is even
cheaper (because FILTER_KEY used to call into the runtime anyway).
And ForInFilter returns either the name or undefined, which makes it
possible to remove the control flow construction from the AstGraphBuilder,
and thereby make both the initialization and the per-loop code of for-in
optimizable later (in typed lowering).
R=jarin@chromium.org
Review URL: https://codereview.chromium.org/1160983004
Cr-Commit-Position: refs/heads/master@{#28711}
The SimplifiedOperatorReducer is (mostly) unused, except for the very
rough store elimination, and just eats compilation time.
R=jarin@chromium.org
Review URL: https://codereview.chromium.org/1162563002
Cr-Commit-Position: refs/heads/master@{#28673}
This adds a new external type (v8::SharedArrayBuffer) that uses a JSArrayBuffer
under the hood. It can be distinguished from an ArrayBuffer by the newly-added
is_shared() bit.
Currently there is no difference in functionality between a SharedArrayBuffer
and an ArrayBuffer. However, a future CL will add the Atomics API, which is
only available on an SharedArrayBuffer. All non-atomic accesses are identical
to ArrayBuffer accesses.
LOG=N
BUG=
Review URL: https://codereview.chromium.org/1136553006
Cr-Commit-Position: refs/heads/master@{#28594}
Reason for revert:
breaks build
Original issue's description:
> Implement SharedArrayBuffer.
>
> This adds a new external type (v8::SharedArrayBuffer) that uses a JSArrayBuffer under the hood. It can be distinguished from an ArrayBuffer by the newly-added is_shared() bit.
>
> Currently there is no difference in functionality between a SharedArrayBuffer and an ArrayBuffer. However, a future CL will add the Atomics API, which is only available on an SharedArrayBuffer. All non-atomic accesses are identical to ArrayBuffer accesses.
>
> BUG=
>
> Committed: https://crrev.com/57170bff7baf341c666252a7f6a49e9c08d51263
> Cr-Commit-Position: refs/heads/master@{#28588}
TBR=jarin@chromium.org,jochen@chromium.org,binji@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=
Review URL: https://codereview.chromium.org/1149203003
Cr-Commit-Position: refs/heads/master@{#28589}
This adds a new external type (v8::SharedArrayBuffer) that uses a JSArrayBuffer under the hood. It can be distinguished from an ArrayBuffer by the newly-added is_shared() bit.
Currently there is no difference in functionality between a SharedArrayBuffer and an ArrayBuffer. However, a future CL will add the Atomics API, which is only available on an SharedArrayBuffer. All non-atomic accesses are identical to ArrayBuffer accesses.
BUG=
Review URL: https://codereview.chromium.org/1136553006
Cr-Commit-Position: refs/heads/master@{#28588}
