[llvm] [X86] Add vXi64 MULHU lowering, keeping full-width products scalar (PR #206983)

[Simon Pilgrim via llvm-commits]

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@@ -369,78 +369,73 @@ define <4 x i64> @dont_fold_urem_i64(<4 x i64> %x) {
 ;
 ; AVX2-LABEL: dont_fold_urem_i64:
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RKSimon wrote:

update test name (or at least the comment at the top) :)

https://github.com/llvm/llvm-project/pull/206983