[PATCH] D108112: [LoopIdiom] Let LIR fold memset pointer / stride SCEV regarding loop guards

[Yueh-Ting Chen via Phabricator via llvm-commits]

eopXD added a comment.

Hi @bmahjour,

Sorry for such delay.

I think the example you raised don't cause a problem to the current implementation.
The comparison is between "pointer stride" and "memset size", which all need to be non-negative.
The start/end of the induction variable don't matter because if the origin stride is negative it will be turned positive before comparison.

I have addressed your comment on renaming the SCEV folding structure and added test case for negative start loops like your example.
(Your example is loop strided store, I modified it to memset in the examples)


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