[llvm] [X86] Use GFNI for vXi8 shifts/rotates (PR #89115)

[Phoebe Wang via llvm-commits]

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@@ -31345,7 +31392,8 @@ static SDValue LowerBITREVERSE(SDValue Op, const X86Subtarget &Subtarget,
   // If we have GFNI, we can use GF2P8AFFINEQB to reverse the bits.
   if (Subtarget.hasGFNI()) {
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phoebewang wrote:

Do we need to check AVX/AVX512 feature here?

https://github.com/llvm/llvm-project/pull/89115