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[JumpThreading] Use runtime parameter to allow for DT and LVI preservation.

Authored by brzycki on Oct 4 2017, 1:05 PM.



The flag "print-lvi-after-jump-threading" determines if DT and LVI should be preserved in JumpThreading. The default is to disable preservation.

I have concerns with this approach as it requires passes that want to rely on LVI and DT to also understand the conditional nature of JumpThreading. This may complicate work like D34135 .

I am posting it here in case it is useful in profiling compile time deltas.

This patch requires D38558 to be applied first in order to function.

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brzycki created this revision.Oct 4 2017, 1:05 PM
brzycki edited the summary of this revision. (Show Details)Oct 4 2017, 1:06 PM
brzycki abandoned this revision.Dec 7 2017, 2:25 PM

I'd rather not use a flag to enable Dominance. The newer patch D40146 uses a deferred preservation method to reclaim performance.