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}
