Reland of https://chromium-review.googlesource.com/c/v8/v8/+/727893
The crashes should be fixed by https://chromium-review.googlesource.com/c/v8/v8/+/763531
Original change's description:
> Revert "Reland^5 "[turbofan] eagerly prune None types and deadness from the graph""
>
> This reverts commit ac0661b358.
>
> Reason for revert: Clusterfuzz unhappy: chromium:783019 chromium:783035
>
> Original change's description:
> > Reland^5 "[turbofan] eagerly prune None types and deadness from the graph"
> >
> > This gives up on earlier attempts to interpret DeadValue as a signal of
> > unreachable code. This does not work because free-floating dead value
> > nodes, and even pure branch nodes that use them, can get scheduled so
> > early that they get reachable. Instead, we now eagerly remove branches
> > that use DeadValue in DeadCodeElimination and replace DeadValue inputs
> > to value phi nodes with dummy values.
> >
> > Reland of https://chromium-review.googlesource.com/715716
> >
> > Bug: chromium:741225 chromium:776256
> > Change-Id: I251efd507c967d4a8882ad8fd2fd96c4185781fe
> > Reviewed-on: https://chromium-review.googlesource.com/727893
> > Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
> > Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#49188}
>
> TBR=jarin@chromium.org,tebbi@chromium.org
>
> Bug: chromium:741225 chromium:776256 chromium:783019 chromium:783035
> Change-Id: I6a8fa3a08ce2824a858ae01817688e63ed1f442e
> Reviewed-on: https://chromium-review.googlesource.com/758770
> Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
> Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#49262}
TBR=jarin@chromium.org,tebbi@chromium.org
# Not skipping CQ checks because original CL landed > 1 day ago.
Bug: chromium:741225 chromium:776256 chromium:783019 chromium:783035
Change-Id: I6c02b4beb02997ec34015ed2f6791a93c70f5e36
Reviewed-on: https://chromium-review.googlesource.com/772150
Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49429}
This reverts commit ac0661b358.
Reason for revert: Clusterfuzz unhappy: chromium:783019 chromium:783035
Original change's description:
> Reland^5 "[turbofan] eagerly prune None types and deadness from the graph"
>
> This gives up on earlier attempts to interpret DeadValue as a signal of
> unreachable code. This does not work because free-floating dead value
> nodes, and even pure branch nodes that use them, can get scheduled so
> early that they get reachable. Instead, we now eagerly remove branches
> that use DeadValue in DeadCodeElimination and replace DeadValue inputs
> to value phi nodes with dummy values.
>
> Reland of https://chromium-review.googlesource.com/715716
>
> Bug: chromium:741225 chromium:776256
> Change-Id: I251efd507c967d4a8882ad8fd2fd96c4185781fe
> Reviewed-on: https://chromium-review.googlesource.com/727893
> Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
> Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#49188}
TBR=jarin@chromium.org,tebbi@chromium.org
Bug: chromium:741225 chromium:776256 chromium:783019 chromium:783035
Change-Id: I6a8fa3a08ce2824a858ae01817688e63ed1f442e
Reviewed-on: https://chromium-review.googlesource.com/758770
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49262}
This gives up on earlier attempts to interpret DeadValue as a signal of
unreachable code. This does not work because free-floating dead value
nodes, and even pure branch nodes that use them, can get scheduled so
early that they get reachable. Instead, we now eagerly remove branches
that use DeadValue in DeadCodeElimination and replace DeadValue inputs
to value phi nodes with dummy values.
Reland of https://chromium-review.googlesource.com/715716
Bug: chromium:741225 chromium:776256
Change-Id: I251efd507c967d4a8882ad8fd2fd96c4185781fe
Reviewed-on: https://chromium-review.googlesource.com/727893
Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49188}
This completely removes translation of exception handler predictions
from the graph IR. We now rely on the runtime using deoptimization
infomation via {FrameSummary} for predictions in optimized code.
R=bmeurer@chromium.org
Review-Url: https://codereview.chromium.org/2207533002
Cr-Commit-Position: refs/heads/master@{#38250}
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}
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}