This is a reland of 6b690a6b48.
The previous version of this CL was a bit too aggressive in the
duplication of branch conditions. This caused an increase in
register pressure in some cases, thus reducing performance.
In fact, duplicating branch conditions that require an "== 0" to be
added provides no benefits. We are thus now a bit less aggressive, and
only duplicate comparisons.
Original change's description:
> Reland [compiler] Simplify "==0" branches in MachineOperatorReducer
>
> This is a reland of 48b443f692.
>
> While fixing the initial CL, we stumbled upon a few bugs that
> we had to fix:
>
> - CommonOperatorReducer and SimplifiedOperatorReducer were applied
> before and after SimplifiedLowering, but always assumed that it
> was before SimplifiedLowering, and thus had the wrong semantics
> for branches in some cases. They now have an added parameter to
> know which semantics of branch they should use.
>
> - The lowering of StaticAssert was wrong and could leave kHeapConstant
> in the assert (instead of machine Booleans).
>
> Original change's description:
> > [compiler] Simplify "==0" branches in MachineOperatorReducer
> >
> > Bug: v8:12484
> > Change-Id: I0667c7464c0dd71338bc199a24a69248a7a0a525
> > Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3497303
> > Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
> > Owners-Override: Tobias Tebbi <tebbi@chromium.org>
> > Commit-Queue: Darius Mercadier <dmercadier@chromium.org>
> > Cr-Commit-Position: refs/heads/main@{#79379}
>
> Bug: v8:12484
> Change-Id: Ibbf5df96fce5ccb04868dc517539479bf69f5703
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3516869
> Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
> Commit-Queue: Darius Mercadier <dmercadier@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#79528}
Bug: v8:12484
Change-Id: I31f575a59811a83c7c1acb4c14bf5ded63a8f536
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3540102
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Commit-Queue: Darius Mercadier <dmercadier@chromium.org>
Cr-Commit-Position: refs/heads/main@{#79560}
This reverts commit 6b690a6b48.
Reason for revert: causes a few regressions here https://chromeperf.appspot.com/group_report?rev=79528
Original change's description:
> Reland [compiler] Simplify "==0" branches in MachineOperatorReducer
>
> This is a reland of 48b443f692.
>
> While fixing the initial CL, we stumbled upon a few bugs that
> we had to fix:
>
> - CommonOperatorReducer and SimplifiedOperatorReducer were applied
> before and after SimplifiedLowering, but always assumed that it
> was before SimplifiedLowering, and thus had the wrong semantics
> for branches in some cases. They now have an added parameter to
> know which semantics of branch they should use.
>
> - The lowering of StaticAssert was wrong and could leave kHeapConstant
> in the assert (instead of machine Booleans).
>
> Original change's description:
> > [compiler] Simplify "==0" branches in MachineOperatorReducer
> >
> > Bug: v8:12484
> > Change-Id: I0667c7464c0dd71338bc199a24a69248a7a0a525
> > Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3497303
> > Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
> > Owners-Override: Tobias Tebbi <tebbi@chromium.org>
> > Commit-Queue: Darius Mercadier <dmercadier@chromium.org>
> > Cr-Commit-Position: refs/heads/main@{#79379}
>
> Bug: v8:12484
> Change-Id: Ibbf5df96fce5ccb04868dc517539479bf69f5703
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3516869
> Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
> Commit-Queue: Darius Mercadier <dmercadier@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#79528}
Bug: v8:12484
Change-Id: I457464d793e9c5af8448564aa3b46be863b96fbb
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3540148
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Commit-Queue: Darius Mercadier <dmercadier@chromium.org>
Cr-Commit-Position: refs/heads/main@{#79552}
This is a reland of 48b443f692.
While fixing the initial CL, we stumbled upon a few bugs that
we had to fix:
- CommonOperatorReducer and SimplifiedOperatorReducer were applied
before and after SimplifiedLowering, but always assumed that it
was before SimplifiedLowering, and thus had the wrong semantics
for branches in some cases. They now have an added parameter to
know which semantics of branch they should use.
- The lowering of StaticAssert was wrong and could leave kHeapConstant
in the assert (instead of machine Booleans).
Original change's description:
> [compiler] Simplify "==0" branches in MachineOperatorReducer
>
> Bug: v8:12484
> Change-Id: I0667c7464c0dd71338bc199a24a69248a7a0a525
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3497303
> Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
> Owners-Override: Tobias Tebbi <tebbi@chromium.org>
> Commit-Queue: Darius Mercadier <dmercadier@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#79379}
Bug: v8:12484
Change-Id: Ibbf5df96fce5ccb04868dc517539479bf69f5703
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3516869
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Commit-Queue: Darius Mercadier <dmercadier@chromium.org>
Cr-Commit-Position: refs/heads/main@{#79528}
Since it will be patched in later in the cases where it will be used,
there is no need to have it as a parameter.
Bug: v8:7790
Change-Id: I93b27f3baf8c3841a60f5ac5ed09993d1caf19bc
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2351667
Reviewed-by: Georg Neis <neis@chromium.org>
Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
Cr-Commit-Position: refs/heads/master@{#69366}
This CL adds functionality to read the source positions directly
from the JS heap rather than from serialized data.
In order to do this, we create a PersistentHandles container in the
OptimizedCompilationInfo which gets passed onto the JSHeapBroker. This
allows us to create the handles in the main thread and pass them safely
to the background thread.
In order to read safely from the background thread, we need a LocalHeap
which blocks the GC from running and potentially moving the handles.
This LocalHeap is created only when the JSHeapBroker has finalized
serializing and destroyed when retiring it.
Bug: v8:7790
Change-Id: I19f8b08d12e5be0a3df34d6af2043310c0c7b6fe
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2277802
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68836}
... to OptimizedCompilationInfo, BytecodeGraphBuilder, and
JSHeapBroker.
Also add first uses of these flags in pipeline.cc by skipping certain
phases when nci is enabled. With this change, tests in the NCI variant
will start to fail since generic lowering is not fully implemented.
These implementations will follow incrementally in the next days.
Bug: v8:8888
Change-Id: I3f570fb92f09059d1f1f4015f88ffe80ccf746ad
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2239572
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68339}
This reverts commit 0c72c71900.
Reason for revert: Wasm code size increase because not all pipelines use CommonOperatorReducer
Original change's description:
> Move branch inversion on ==0 into platform-agnostic reducer
>
> This change is based on a discussion from
> https://crrev.com/c/v8/v8/+/2053769/4/src/compiler/machine-operator-reducer.cc#1696
> wherein Tobias suggested moving the folding away of ==0 operations out
> of the platform-specific instruction selectors and into the
> MachineOperatorReducer. I noticed that CommonOperatorReducer already
> handles some very similar cases, so I have tried putting the ==0 folding
> into CommonOperatorReducer instead. I'm happy to move it into
> MachineOperatorReducer if that's better; I still don't have a very good
> understanding of how roles are separated among reducers.
>
> Change-Id: Ia0285bd9fafeef29d87cc88654bd6d355d467e8f
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2076498
> Commit-Queue: Seth Brenith <seth.brenith@microsoft.com>
> Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
> Reviewed-by: Clemens Backes <clemensb@chromium.org>
> Reviewed-by: Georg Neis <neis@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#66688}
# Not skipping CQ checks because original CL landed > 1 day ago.
Bug: chromium:1061767
Change-Id: Id1fdfb38357eb514d92ed3be0a683f077202faa4
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2117789
Commit-Queue: Seth Brenith <seth.brenith@microsoft.com>
Reviewed-by: Georg Neis <neis@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#66862}
This change is based on a discussion from
https://crrev.com/c/v8/v8/+/2053769/4/src/compiler/machine-operator-reducer.cc#1696
wherein Tobias suggested moving the folding away of ==0 operations out
of the platform-specific instruction selectors and into the
MachineOperatorReducer. I noticed that CommonOperatorReducer already
handles some very similar cases, so I have tried putting the ==0 folding
into CommonOperatorReducer instead. I'm happy to move it into
MachineOperatorReducer if that's better; I still don't have a very good
understanding of how roles are separated among reducers.
Change-Id: Ia0285bd9fafeef29d87cc88654bd6d355d467e8f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2076498
Commit-Queue: Seth Brenith <seth.brenith@microsoft.com>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#66688}
Got rid of the following circular header dependency chains:
compilation-dependencies <-> js-heap-broker <-> access-info
types <-> js-heap-broker <-> access-info
Extracted former CompilationDependencies::Dependency class into its own header.
Extracted *Ref classes into their own header.
This should enable building on older GCC versions, e.g. 5.4.0.
Bug: v8:9440
Change-Id: Ia345bc227d8f7806d0b8622b706346a7ce6d01ea
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1687415
Commit-Queue: Maya Lekova <mslekova@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Reviewed-by: Michael Stanton <mvstanton@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62541}
In native context specialization, reducing a JSResolvePromise
node requires us to know that there are no "then" properties on
the resolution object's maps. This work must be done at serialization
time.
Bug: v8:7790
Change-Id: If905513a028bc3d71379e2a31e86fff1d3383141
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1666988
Reviewed-by: Georg Neis <neis@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Commit-Queue: Michael Stanton <mvstanton@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62519}
As a component of the wider Turbofan logging scheme, it makes sense
for JSHeapBroker logging to come through flags specified in the
OptimizedCompilationInfo class, which uses --trace-turbo-filter
to control which functions are logged.
Bug: v8:7790
Change-Id: I3b068d8be78867ab0bd9607dda9eca4123b9d7b1
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1655297
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Commit-Queue: Michael Stanton <mvstanton@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62111}
We'll soon start collecting data from the JS heap prior to the typed
lowering pass, and then refrain from reading the heap in that pass.
This CL prepares the broker machinery by introducing a hash table that
maps an object (handle) to the corresponding cached data. For the time
being, that cached data is essentially just the handle itself.
Bug: v8:7790
Change-Id: I830e9c72faafb7ae1d10e8a111636b3a3762bbc6
Reviewed-on: https://chromium-review.googlesource.com/1143405
Commit-Queue: Georg Neis <neis@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#54618}
Removes use of HeapObject::GetIsolate() from Object::BooleanValue in
preparation for removing the method.
Requires adding Isolate parameter to CommonOperatorReducer constructor.
Bug: v8:7786
Cq-Include-Trybots: luci.chromium.try:linux_chromium_rel_ng;luci.v8.try:v8_linux_noi18n_rel_ng
Change-Id: If735e71df3288bf1eb11576605c2d95a19472181
Reviewed-on: https://chromium-review.googlesource.com/1071653
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Dan Elphick <delphick@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53361}
Where the value we are switching on is a constant, we can just look
through each IfValue case and replace the switch and go straight to
the appropriate case. If no case matches, expect and go to the
IfDefault.
For the (unrealistic) example in the linked bug, this improves
performance ~1.5x.
Bug: v8:7389
Change-Id: I7ffe209bda9ed22571ea106396b18e0bcf9a1e22
Reviewed-on: https://chromium-review.googlesource.com/893141
Commit-Queue: Peter Marshall <petermarshall@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51029}
The existing implementation assumes that return nodes have exactly one
real value input. This assumption does not hold for WebAssembly. To
avoid incorrect behavior, this CL turns of the reduction of returns
with a value input count != 1.
R=titzer@chromium.org, mstarzinger@chromium.org
Review-Url: https://codereview.chromium.org/2638053002
Cr-Commit-Position: refs/heads/master@{#42425}
This is preparation for using TF to create builtins that handle variable number of
arguments and have to remove these arguments dynamically from the stack upon
return.
The gist of the changes:
- Added a second argument to the Return node which specifies the number of stack
slots to pop upon return in addition to those specified by the Linkage of the
compiled function.
- Removed Tail -> Non-Tail fallback in the instruction selector. Since TF now should
handles all tail-call cases except where the return value type differs, this fallback
was not really useful and in fact caused unexpected behavior with variable
sized argument popping, since it wasn't possible to materialize a Return node
with the right pop count from the TailCall without additional context.
- Modified existing Return generation to pass a constant zero as the additional
pop argument since the variable pop functionality
LOG=N
Review-Url: https://codereview.chromium.org/2446543002
Cr-Commit-Position: refs/heads/master@{#40699}
Reason for revert:
Seems to break arm64 sim debug and blocks roll:
https://build.chromium.org/p/client.v8.ports/builders/V8%20Linux%20-%20arm64%20-%20sim%20-%20debug/builds/3294
Original issue's description:
> [turbofan] Support variable size argument removal in TF-generated functions
>
> This is preparation for using TF to create builtins that handle variable number of
> arguments and have to remove these arguments dynamically from the stack upon
> return.
>
> The gist of the changes:
> - Added a second argument to the Return node which specifies the number of stack
> slots to pop upon return in addition to those specified by the Linkage of the
> compiled function.
> - Removed Tail -> Non-Tail fallback in the instruction selector. Since TF now should
> handles all tail-call cases except where the return value type differs, this fallback
> was not really useful and in fact caused unexpected behavior with variable
> sized argument popping, since it wasn't possible to materialize a Return node
> with the right pop count from the TailCall without additional context.
> - Modified existing Return generation to pass a constant zero as the additional
> pop argument since the variable pop functionality
>
> LOG=N
TBR=bmeurer@chromium.org,mstarzinger@chromium.org,epertoso@chromium.org,danno@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
NOPRESUBMIT=true
Review-Url: https://codereview.chromium.org/2473643002
Cr-Commit-Position: refs/heads/master@{#40691}
This is preparation for using TF to create builtins that handle variable number of
arguments and have to remove these arguments dynamically from the stack upon
return.
The gist of the changes:
- Added a second argument to the Return node which specifies the number of stack
slots to pop upon return in addition to those specified by the Linkage of the
compiled function.
- Removed Tail -> Non-Tail fallback in the instruction selector. Since TF now should
handles all tail-call cases except where the return value type differs, this fallback
was not really useful and in fact caused unexpected behavior with variable
sized argument popping, since it wasn't possible to materialize a Return node
with the right pop count from the TailCall without additional context.
- Modified existing Return generation to pass a constant zero as the additional
pop argument since the variable pop functionality
LOG=N
Review-Url: https://codereview.chromium.org/2446543002
Cr-Commit-Position: refs/heads/master@{#40678}
Fold a Select that negates a boolean value, i.e. returning true in the
false case and vice versa, into Branch users, similar to what we already
do for Branch nodes with BooleanNot inputs.
BUG=v8:5267
Review-Url: https://codereview.chromium.org/2308303003
Cr-Commit-Position: refs/heads/master@{#39149}
So far we don't have a useful way to inline Math.max or Math.min in
TurboFan optimized code. This adds new operators NumberMax and NumberMin
and changes the Float64Max/Float64Min operators to have JavaScript
semantics instead of the C++ semantics that it had previously.
This also removes support for recognizing the tenary case in the
CommonOperatorReducer, since that doesn't seem to have any positive
impact (and actually doesn't show up in regular JavaScript, where
people use Math.max/Math.min instead).
Drive-by-fix: Also nuke the unused Float32Max/Float32Min operators.
R=jarin@chromium.org
Review-Url: https://codereview.chromium.org/2170343002
Cr-Commit-Position: refs/heads/master@{#37971}
Remove dead code to optimize Int64Constants as branch/select conditions,
because we either have tagged booleans or bits represented as word32.
R=jarin@chromium.org
Review-Url: https://codereview.chromium.org/1994533002
Cr-Commit-Position: refs/heads/master@{#36308}
MachineType is now a class with two enum fields:
- MachineRepresentation
- MachineSemantic
Both enums are usable on their own, and this change switches some places from using MachineType to use just MachineRepresentation. Most notably:
- register allocator now uses just the representation.
- Phi and Select nodes only refer to representations.
Review URL: https://codereview.chromium.org/1513543003
Cr-Commit-Position: refs/heads/master@{#32738}
This will enable tail call optimization even across inlining. Plus it
might enable some other interesting optimizations as well. In order to
avoid blowing up the generated code, we can still canonicalize the
epilogue in the CodeGenerator, similar to what fullcodegen does.
R=jarin@chromium.org
Review URL: https://codereview.chromium.org/1215623002
Cr-Commit-Position: refs/heads/master@{#29311}
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}
This turns the CommonOperatorReducer into an AdvancedReducer and makes
it independent of JSGraph (which was used only because it was convienent),
and let's the CommonOperatorReducer run together with the ControlReducer.
The ControlReducer is still not able to run together with other reducers,
but we're getting closer. The plan is to split the ControlReducer into
two parts: The dead code elimination part and the common operator
reduction part. This separation will help to avoid tricky bugs in the
future and should make testing a *lot* easier.
R=jarin@chromium.org
Review URL: https://codereview.chromium.org/1192063002
Cr-Commit-Position: refs/heads/master@{#29105}
Currently we always generate a diamond in the graph builder for every
legacy const context slot, which we cannot get rid of until late control
reduction, even if we know after context specialization that the slot is
already initialized.
Now we generate a select instead, which the CommonOperatorReducer
happily removes during typed lowering. This greatly speeds up asm.js
code generated by Emscripten with the new POINTER_MASKING mode.
R=mstarzinger@chromium.org
Review URL: https://codereview.chromium.org/1072353002
Cr-Commit-Position: refs/heads/master@{#27739}
These operators compute the absolute floating point value of some
arbitrary input, and are implemented without any branches (i.e. using
vabs on arm, and andps/andpd on x86).
R=svenpanne@chromium.org
Review URL: https://codereview.chromium.org/1066393002
Cr-Commit-Position: refs/heads/master@{#27662}
Basically recognize certain x < y ? x : y constructs and turn that into
Float64Min/Float64Max operations, if the target machine supports that.
On x86 we lower to (v)minsd/(v)maxsd.
R=dcarney@chromium.org
Review URL: https://codereview.chromium.org/998283002
Cr-Commit-Position: refs/heads/master@{#27160}
- Move NodeMarker to its own file, and introduce a non
templatized base class.
- Cleanup the include hell.
- Sanitize the Node construction methods now that we
got rid of that GenericNode/GenericGraph stuff.
- Protect against NodeId overflow in Graph.
- Various minor cleanups.
TEST=cctest,mjsunit,unittests
Review URL: https://codereview.chromium.org/838783002
Cr-Commit-Position: refs/heads/master@{#25977}
The CommonOperatorReducer currently takes care of redundant Phis,
EffectPhis and Selects. This functionality overlaps with ControlReducer,
but is required to make certain optimizations effective, since the
ControlReducer only runs really early and really late in the pipeline
and therefore other reducers aren't reapplied properly after redundant
phi/select elimination.
TEST=unittests
R=hpayer@chromium.org
Review URL: https://codereview.chromium.org/817243003
Cr-Commit-Position: refs/heads/master@{#25922}
