[llvm] [RISCV] Add mvendorid/marchid/mimpid to CPU definitions (PR #116202)

[Craig Topper via llvm-commits]

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@@ -32,6 +32,21 @@ struct RISCVExtensionBitmask {
 };
 } // namespace RISCVExtensionBitmaskTable
 
+struct CPUModel {
+  uint32_t MVendorID;
+  uint64_t MArchID;
+  uint64_t MImpID;
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topperc wrote:

MImplID to match the name of the CSR?

https://github.com/llvm/llvm-project/pull/116202