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

[Shengchen Kan via llvm-commits]

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@@ -1523,31 +1523,51 @@ def MOVDIR64B64_EVEX : I<0xF8, MRMSrcMem, (outs), (ins GR64:$dst, i512mem_GR64:$
 // ENQCMD/S - Enqueue 64-byte command as user with 64-byte write atomicity
 //
 let SchedRW = [WriteStore], Defs = [EFLAGS] in {
-  def ENQCMD16 : I<0xF8, MRMSrcMem, (outs), (ins GR16:$dst, i512mem:$src),
+  def ENQCMD16 : I<0xF8, MRMSrcMem, (outs), (ins GR16:$dst, i512mem_GR16:$src),
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KanRobert wrote:

Extract this into a separate commit and add a test

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