[llvm] [X86][MC] Support Enc/Dec for NF BMI instructions (PR #76709)

[Shengchen Kan via llvm-commits]

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@@ -1050,10 +1050,14 @@ multiclass AndN<X86TypeInfo t, string suffix> {
 
 // Complexity is reduced to give and with immediate a chance to match first.
 let AddedComplexity = -6 in {
-defm ANDN32 : AndN<Xi32, "">, VEX, Requires<[HasBMI, NoEGPR]>;
-defm ANDN64 : AndN<Xi64, "">, VEX, REX_W, Requires<[HasBMI, NoEGPR]>;
+defm ANDN32 : AndN<Xi32>, VEX, Requires<[HasBMI, NoEGPR]>;
+defm ANDN64 : AndN<Xi64>, VEX, REX_W, Requires<[HasBMI, NoEGPR]>;
 defm ANDN32 : AndN<Xi32, "_EVEX">, EVEX, Requires<[HasBMI, HasEGPR, In64BitMode]>;
 defm ANDN64 : AndN<Xi64, "_EVEX">, EVEX, REX_W, Requires<[HasBMI, HasEGPR, In64BitMode]>;
+let Pattern = [(null_frag)] in {
+  defm ANDN32 : AndN<Xi32, "_NF">, EVEX, EVEX_NF, Requires<[In64BitMode]>;
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KanRobert wrote:

Bug here. class `AndN` iherits class `DefEFLAGS`.

https://github.com/llvm/llvm-project/pull/76709