[PATCH] D101297: [SLP]Allow masked gathers only if allowed by target.

[Alexey Bataev via Phabricator via llvm-commits]

ABataev added inline comments.


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Comment at: llvm/test/Transforms/SLPVectorizer/X86/pr47629.ll:376
+; AVX-NEXT:    [[TMP10:%.*]] = bitcast i32* [[T0:%.*]] to <8 x i32>*
+; AVX-NEXT:    store <8 x i32> [[TMP9]], <8 x i32>* [[TMP10]], align 4, !tbaa [[TBAA0]]
 ; AVX-NEXT:    ret void
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spatel wrote:
> Seems like an improvement, but do you know what happens on this example? There's no masked gather, but that interfered with the cost calc for forming the vector add or store?
Yes, the target does not support masked gather and we overestimate the cost of the masked memory operations. Because of that, we could not vectorize this sequence previously. With legality checks, simple gather makes it profitable for vectorization.


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  https://reviews.llvm.org/D101297/new/

https://reviews.llvm.org/D101297