We need to account for AVX1 targets splitting 256-bit PMULUDQ style patterns - we included a AVX2 cost, but missed out AVX1 despite v4i64 being a legal type Noticed while working on #156568
We need to account for AVX1 targets splitting 256-bit PMULUDQ style patterns - we included a AVX2 cost, but missed out AVX1 despite v4i64 being a legal type Noticed while working on #156568