[PATCH] D107964: [LoopIdiom] Don't transform loop into memmove when load from body has more than one use

Fri Aug 13 06:43:06 PDT 2021

yurai007 added a comment.

@efriedma @lebedev.ri:

> I think this belongs earlier, with the other mayLoopAccessLocation check? It's basically a variation of the same check.

> can we retain the transform by querying AA that there's no overlap?

I'm not sure if I follow your comments regarding AA (done in mayLoopAccessLocation). The problem in UT is not about 'load'-'store' relationship but about 'load'-'add' pair. 
'Load' has 2 users - 'store' and 'add'. How AA can help in case when 'add' instruction is not seen by getModRefInfo at all? Currently getModRefInfo says always NoModRef when reaching 'add'.

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https://reviews.llvm.org/D107964