[llvm] [X86][MC] Support Enc/Dec for NF for promoted BMI instructions in 73899 (PR #76709)

[Phoebe Wang via llvm-commits]

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@@ -1171,7 +1186,7 @@ static int getInstructionID(struct InternalInstruction *insn,
         attrMask |= ATTR_EVEXB;
       // nf bit is the MSB of aaa
       if (nfFromEVEX4of4(insn->vectorExtensionPrefix[3]) &&
-          insn->opcodeType == MAP4)
+          (insn->opcodeType == MAP4 || isNFnotMap4(insn)))
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phoebewang wrote:

Merge this into a function like `isNF(insn)`?

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