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

[Shengchen Kan via llvm-commits]

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@@ -1309,6 +1318,13 @@ let Predicates = [HasBMI2, HasEGPR, In64BitMode], Defs = [EFLAGS] in {
   defm BZHI64 : Bmi4VOp3<0xF5, "bzhi", Xi64, X86bzhi, WriteBZHI, "_EVEX">, EVEX;
 }
 
+let Predicates = [In64BitMode], Pattern = [(null_frag)] in {
+  defm BEXTR32 : Bmi4VOp3<0xF7, "bextr", Xi32, X86bextr, WriteBEXTR, "_NF">, EVEX, EVEX_NF;
+  defm BEXTR64 : Bmi4VOp3<0xF7, "bextr", Xi64, X86bextr, WriteBEXTR, "_NF">, EVEX, EVEX_NF;
+  defm BZHI32 : Bmi4VOp3<0xF5, "bzhi", Xi32, X86bzhi, WriteBZHI, "_NF">, EVEX, EVEX_NF;
+  defm BZHI64 : Bmi4VOp3<0xF5, "bzhi", Xi64, X86bzhi, WriteBZHI, "_NF">, EVEX, EVEX_NF;
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KanRobert wrote:

Change X86bextr to null_frag and remove `Pattern = [(null_frag)] `

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