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 is needed in order to allow expansion of a throwing node into a
set of nodes that produce different effects for the successful and the
exceptional continuation.
R=bmeurer@chromium.org
Review URL: https://codereview.chromium.org/1179543002
Cr-Commit-Position: refs/heads/master@{#28918}
This deprecates the aforementioned mutator in favor of a simpler
NodeProperties::ReplaceUses that doesn't perform any relaxation.
Preparation for enabling support for try-catch statements.
R=bmeurer@chromium.org
TEST=unittests/NodePropertiesTest
Review URL: https://codereview.chromium.org/1172773003
Cr-Commit-Position: refs/heads/master@{#28897}
This introduces a conservative prediction for each exception handler
whether it will locally catch an exception or re-throw it to outside
the code bondaries. It will allow for a more intuitive prediction of
whether an exception is considered "caught" or "uncaught".
R=bmeurer@chromium.org,yangguo@chromium.org
BUG=chromium:492522
LOG=N
Review URL: https://codereview.chromium.org/1158563008
Cr-Commit-Position: refs/heads/master@{#28681}
- Make Node::Inputs and Node::Uses mostly STL compliant.
- Get rid of some pre-C++11 crappiness.
- Start moving unit tests from cctest to unittests.
- TrimInputCount() now tries to reserve inputs slots for
later appending.
- Fix numerous style guide violations.
TEST=cctest,unittests
R=dcarney@chromium.org
Review URL: https://codereview.chromium.org/851263002
Cr-Commit-Position: refs/heads/master@{#26098}