C#: Apply static CFG splitting limit#1673
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The predicate `maxSplits()` was previously applied dynamically to ensure that
any control flow node would keep track of at most `maxSplits()` number of splits.
However, there was no guarantee that two different copies of the same AST element
wouldn't contain different splits, so in general the number of copies for a given
AST element `e` could be on the order `$\binom{n}{k}c^k$`, where `n` is the total
number of splits that apply to `e`, `k = maxSplits()`, and `c` is a constant.
With this change, the relevant splits for `e` are instead computed statically,
meaning that the order is instead `$c^k$`.
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Overall LGTM, a few small questions.
calumgrant
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Aug 15, 2019
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The predicate
maxSplits()was previously applied dynamically to ensure thatany control flow node would keep track of at most
maxSplits()number of splits.However, there was no guarantee that two different copies of the same AST element
wouldn't contain different splits, so in general the number of copies for a given
AST element
ecould be on the order$\binom{n}{k}c^k$, wherenis the totalnumber of splits that apply to
e,k = maxSplits(), andcis a constant.With this change, the relevant splits for
eare instead computed statically,meaning that the order is instead
$c^k$.Profiling report here (internal link).