[clang] [llvm] [RISCV] Add CSRs and an instruction for Smctr and Ssctr extensions. (PR #105148)

[Yingwei Zheng via cfe-commits]

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@@ -1054,6 +1054,19 @@ def FeatureStdExtSupm
     : RISCVExperimentalExtension<"supm", 1, 0,
                                  "'Supm' (Indicates User-mode Pointer Masking)">;
 
+def FeatureStdExtSmctr
+    : RISCVExperimentalExtension<"smctr", 1, 0,
+                                 "'Smctr' (Control Transfer Records Machine Level)",
+                                 [FeatureStdExtSmcsrind]>;
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dtcxzyw wrote:

> Smctr and Ssctr depend on both the implementation of S-mode and the Sscsrind extension.

https://github.com/llvm/llvm-project/pull/105148