[PATCH] D99142: [RISCV] Add basic cost modelling for fixed vector gather/scatter.

[Fraser Cormack via Phabricator via llvm-commits]

frasercrmck added a comment.

I've played around with this for my own benefit, and it looks like illegal-vector scatter/gathers give roughly these scores multiplied by 3 to account for extract_element and some scalarization overhead. Before this patch all vector scatter/gathers are treated as illegal and so all costs are the mul-by-3 ones.

It sounds like this change will affect vectorization decisions. Should we have loop-vectorizer tests to accompany this?


Repository:
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  https://reviews.llvm.org/D99142/new/

https://reviews.llvm.org/D99142