[clang] [X86] Add USER_MSR instructions. (PR #68944)

[Freddy Ye via cfe-commits]

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@@ -241,6 +241,7 @@ X86_FEATURE       (SM3,             "sm3")
 X86_FEATURE       (SM4,             "sm4")
 X86_FEATURE       (AVXVNNIINT16,    "avxvnniint16")
 X86_FEATURE       (EVEX512,         "evex512")
+X86_FEATURE       (USERMSR,            "usermsr")
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FreddyLeaf wrote:

3e32e495d8fa56ad3770769a5d4559ea0a41af96

https://github.com/llvm/llvm-project/pull/68944