[PATCH] D108108: [LoopPeel] Allow peeling with multiple unreachable-terminated exit blocks.

[Nikita Popov via Phabricator via llvm-commits]

nikic added inline comments.


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Comment at: llvm/lib/Transforms/Utils/LoopPeel.cpp:105
+  // The latch must either be the only exiting block or all non-latch exit
+  // blocks are either have an deopt or unreachable terminator.
+  return all_of(Exits, [](const BasicBlock *BB) {
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reames wrote:
> Can you add something to this comment to indicate that a) this is a proxy for a strong profile prediction of untaken, and b) this is a profitability check not a legality check?
I would really appreciate an explanation of why we want this heuristic... it's not really obvious to me why this is only beneficial if the other exits are likely not taken.


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  https://reviews.llvm.org/D108108/new/

https://reviews.llvm.org/D108108