[llvm] [X86][MC] Support Enc/Dec for EGPR for promoted CET instruction (PR #76023)

[Shengchen Kan via llvm-commits]

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@@ -520,6 +520,7 @@ let SchedRW = [WriteSystem] in {
     } // Defs SSP
   } // Uses SSP
 
+let Predicates = [NoEGPR] in {
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KanRobert wrote:

`RDSSPD` is not promoted. I guess it's probably b/c it's used by intrinsic and the dest reg is `RAX` in most cases. 

https://github.com/llvm/llvm-project/pull/76023