[PATCH] D138238: [SROA] Change how we speculate `load`s of `select`s -- split block, insert then/else blocks, form two-entry PHI node

[Roman Lebedev via Phabricator via llvm-commits]

lebedev.ri added inline comments.


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Comment at: llvm/include/llvm/Transforms/Scalar/SROA.h:106-109
-  /// All of these select instructions have been checked for the safety of
-  /// speculation and by being speculated will allow promoting allocas
-  /// currently in the promotable queue.
-  SetVector<SelectInst *, SmallVector<SelectInst *, 2>> SpeculatableSelects;
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arsenm wrote:
> Are there any cases where this should still try to speculate?
I'm not sure i understand the question.
As it can be seen from the rest of the diff here,
for select's, we will always form diamond control flow and two-entry phi node,
and never check if we can speculate load.
For PHI's, we still speculate.


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  https://reviews.llvm.org/D138238/new/

https://reviews.llvm.org/D138238