[PATCH] D53245: Teach the DominatorTree fallback to recalculation when applying updates to speedup JT (PR37929)

[Jakub Kuderski via Phabricator via llvm-commits]

kuhar added a comment.

In https://reviews.llvm.org/D53245#1265405, @NutshellySima wrote:

> For `k>n` you mentioned, I think you mean `k>n/α` (α is a constant) because for the reproducer in 37929, the minimum value of α to make the time consumed by clang acceptable is about 3 (α should definitely be larger than 3). But selecting a higher value like "75" can also boost other inputs more (about 2x~4.5x on `clang*.bc`s).


OK, makes sense if that the case in the bug report.

Would you be able to produce some numbers for clang for a heuristic like this:
`if (n > 100) k * a >n; else if (k > n)`
with different `a`s?


https://reviews.llvm.org/D53245