[llvm] [X86] Support promoted ENQCMD, KEYLOCKER and USER-MSR instructions (PR #77293)

[Shengchen Kan via llvm-commits]

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@@ -1566,7 +1566,27 @@ let SchedRW = [WriteStore], Defs = [EFLAGS] in {
   def ENQCMDS64 : I<0xF8, MRMSrcMem, (outs), (ins GR64:$dst, i512mem_GR64:$src),
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KanRobert wrote:

Use multiclass for this.

https://github.com/llvm/llvm-project/pull/77293