[llvm] [VectorCombine][X86] Use updated getVectorInstrCost hook (PR #137823)

[Simon Pilgrim via llvm-commits]

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@@ -168,11 +168,17 @@ define <2 x i1> @constant_op1_i64_not_undef_lane(i64 %x) {
 ; negative test - load prevents the transform
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RKSimon wrote:

update comments

https://github.com/llvm/llvm-project/pull/137823